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Essay, 44 pages (10000 words)

The pathophysiological relevance of the inkt cell/mononuclear phagocyte crosstalk in tissues

Introduction

Natural Killer T (NKT) cells are a subset of T lymphocytes with innate-like functions characterized by the ability of recognizing lipid antigens presented by the major histocompatibility complex (MHC)-related molecule CD1d ( 1 ). NKT cells can be divided into two groups according on their TCR usage. Type I or invariant (i)NKT cells express a TCR made by the invariant rearrangement Vα14-Jα18 ( TRAV11 TRAJ18 ) in mice, and the orthologous Vα24-Jα18 ( TRAV10 TRAJ18 ) in humans, paired with diverse β-chains that utilize a restricted set of Vβ genes ( 2 , 3 ). Type II NKT cells express different, yet poorly diverse, TCRs other than the semi-invariant Vα14/Vα24 one ( 4 , 5 ). This review will focus on iNKT cells, the most represented and best characterized subset.

iNKT cells are endowed with a constitutive (i. e., innate) effector-memory phenotype: unlike mainstream MHC-restricted T cells, they rapidly produce large amounts of inflammatory and regulatory cytokines and chemokines upon activation without prior antigen sensitization ( 6 , 7 ). This innate reactivity, together with their primary localization in tissues, makes iNKT cells effective sentinels of tissue integrity. Mouse and human iNKT cells have been found in lung, intestinal and urogenital mucosae, skin, fat, parenchymatous organs, as well as secondary lymphoid organs. There, they respond to two main types of stimuli, resulting from cell damage and inflammation induced upon pathological processes, namely: (i). signaling from pro-inflammatory cytokines, particularly IL-12 and IL-18 ( 8 , 9 ); (ii). recognition of microbial or autologous (self) agonist lipids presented by CD1d, which derive from infecting pathogens and from biosynthetic pathways upregulated by stress in immune cells, respectively ( 10 15 ). A critical aspect of this function, supported by increasing body of evidence, seems to be represented by the highly regulated crosstalk between iNKT cells and a broad range of CD1d-expressing cell populations of the mononuclear phagocyte system (MPS), represented by monocytes, macrophages, and DCs ( 10 , 14 19 ). Owed to its extensive diversity and plasticity, the MPS plays essential functions in the organism, including tissue maintenance and healing, innate immune responses and pathogen clearance, and the induction of adaptive immune responses ( 20 22 ). Importantly, the cells of the MPS express CD1d in mice and humans and are strategically positioned in tissues to sense stress and convey it to iNKT cells to coordinate a rapid reaction against it. Through these bidirectional interactions with MPS, iNKT cells rapidly modulate the local microenvironment for an immediate tissue reaction, concurrently helping the induction of subsequent adaptive immune responses. In this review, we propose that the interaction with CD1d-expressing MPS in tissues is the fundamental job of iNKT cells, and we will provide examples of the pathophysiological relevance of such interplay.

Mechanistic Aspects of the iNKT-myeloid Cell Crosstalk

The relevance of the interplay between iNKT cells and MPS populations can be defined as not univocal and linear ( 19 ), but dependent on several factors that can impact the reciprocal cell regulation in vivo such as: (i) the strength of cognate antigen/iTCR signal, co-stimulation and the maturation state of the mononuclear phagocytic cell; (ii) the iNKT cell subset involved in the interaction; (iii) the physiological vs. pathological status of the host. In this review, we add the tissue context as a fourth factor that has acquired relevance in recent years, as accumulating evidences are highlighting the importance of a fine-regulated crosstalk between iNKT cells and CD1d-expressing MPS in tissues for the biology of these cells.

The iNKT cell subsets involved in the interaction with MPS cells and the tissue context are strongly interconnected. Different tissues contain distinct composition of resident iNKT cell subsets, at least in mice ( 23 26 ). Based on the differential expression of three key transcription factors (PLZF, Tbet, RORγt) involved in the determination of specific effector phenotypes, mouse iNKT cells acquire T H 1- (NKT1, PLZF low , Tbet +, RORγt ), T H 2- (NKT2, PLZF high , Tbet , RORγt ), and T H 17-like (NKT17, PLZF int , Tbet low , RORγt high ) cytokine profiles already upon thymic development. Recent reports suggest that this subsets definition for iNKT cells may not entirely represent the whole spectrum of effector functions displayed by these cells, as their effective cytokine production can sometimes deviate from the one expected from their transcription factor profile ( 27 , 28 ). This suggests both that iNKT cells may undergo some sort of post-selection functional tuning, and the need for a more comprehensive phenotypical and functional analysis to define their effector profiles. Nevertheless, each known iNKT cell subset egresses from the thymus to survey different peripheral compartments. In C57BL/6 mice, NKT1 cells comprise the > 95% of all hepatic iNKT cells, and are also predominant in the prostate, while NKT2 and NKT17 ( 29 ) are highly enriched in the intestine and lung mucosae, respectively. In secondary lymphoid organs, NKT1 and some NKT2 cells are contained in the spleen, while LNs harbor NKT1, low NKT2, and expanded NKT17 cells, with the notable exception of mesenteric LNs and Peyer’s Patches, in which iNKT2 represent up to 40% of iNKT cells ( 24 , 30 ). The adipose tissue contains a distinct IL-10 producing regulatory iNKT cell subset (NKT10) ( 25 ), which lacks PLZF but express the transcription factor E4BP4, and whose thymic vs. peripheral differentiation is currently unknown ( 31 , 32 ). The relative frequency and tissue distribution of the iNKT cell subsets varies substantially between different mouse strains, likely correlating with the different dominant types of effector responses classically observed in each strain ( 24 ). iNKT cells are sessile cells that exhibit remarkable tissue-residency and limited recirculation, with the notable exception of those cells found in the peripheral blood ( 23 , 25 ). Together, these characteristics confer iNKT cells a fundamental role in the tissue homeostasis and immune architecture: based on their main cytokine profiles they display in different tissues, iNKT cells modulate in different directions the effector response of the mononuclear phagocytic cells they interact with ( 33 ).

The pathophysiological status of the host can also influence iNKT cell distribution and subset balance, which may directly reflect on their communication with the MPS. For instance the relative composition of NKT1, NKT2, and NKT17 cells in a given tissue may be altered from physiology to pathology, as observed in prostate cancer progression ( 26 ), or in adipose tissue in lean and obese subjects ( 34 , 35 ), impacting the quality of the resulting effector functions. This is an intriguing observation, which points to unanticipated effector plasticity and/or ability to migrate into different tissues of iNKT cells that would be relevant to understand.

A parallel aspect impinging substantially on the iNKT-myeloid cell crosstalk is represented by the functional plasticity characterizing the cells of the MPS, particularly monocytes/macrophages, which directly impact the pathophysiological status of the host. Indeed, monocytes are able to differentiate throughout a broad spectrum of effector phenotypes ranging from strongly pro-inflammatory and tissue damaging, to anti-inflammatory and tissue repairing profiles. For macrophages, this complex functional spectrum has been (over)simplified in the widely recognized paradigm of pro-inflammatory M1 and anti-inflammatory M2 populations, mirroring the T H 1 and T H 2 states of T cells ( 36 ), which represent the two functional extremes of the spectrum ( 37 , 38 ). In vivo , however, macrophages appear often to exhibit mixed phenotypes, with a variable M1/M2 balance, which are modulate by the combination of molecular and cellular signals contained in the local microenvironment, implying a remarkable functional plasticity of this cell population ( 39 ).

The interplay between iNKT cells and MPS cells is mutual and embraces different aspects. iNKT cells depend for their functional education on CD1d + mononuclear phagocytes ( 40 , 41 ). At the same time, the maturation and polarization of DCs and monocytes is promoted by iNKT cells ( 42 , 43 ). Several mechanisms could underlie this interplay, including CD1d engagement ( 44 ), cytokine production ( 45 ), CD40 ligation ( 46 , 47 ), purinergic signaling ( 48 , 49 ). iNKT cell-dependent signaling cues indeed direct the acquisition of either pro-inflammatory or anti-inflammatory effector phenotypes of myeloid cells ( 50 53 ). Based the above considerations, the outcome of the interconnections between iNKT cells and MPS cells in specific anatomical sites can thus be quite different.

Secondary Lymphoid Organs

iNKT cell distribution in secondary lymphoid organs allows them to exert their “ adjuvant” functions for both innate and adaptive immune response, culminating in the non-cognate or cognate help to B cell responses ( 54 58 ). In popliteal LNs at steady state, endogenous iNKT cells localize in the interfollicular region and medulla, but not in the T-cell-rich paracortex ( 59 ), whereas adoptively transferred iNKT cells are found in the paracortex ( 60 ), possibly reflecting the different methods used to detect the cells in situ . In the steady state spleen, both autochthonous and adoptively transferred iNKT cells are found widely distributed throughout the parenchyma, including B and T follicles in the white pulp, the marginal zone (MZ) and the red pulp ( 56 , 61 ). This iNKT cell distribution at is substantially modified upon antigen-dependent activation. In the popliteal LNs, upon immunization of mice with particulated antigens formulated with the strong lipid agonist αGalCer, the adoptively transferred iNKT cells rapidly move from the paracortex to contact CD169 + macrophage lining the subcapsular sinus, which express CD1d and can present lymph-borne soluble antigens, resulting in a strong iNKT cell activation and secreting copious amounts of helper cytokines ( 60 ). In the spleen, the injection of soluble antigen formulated with αGalCer, or of pathogenic bacteria containing stimulatory glycolipids, results in the massive accumulation, within 8 h from administration, of splenic iNKT cells in the MZ, where the cells are activated upon contacting CD1d + DCs, and possibly also macrophages ( 61 , 62 ). This iNKT cell re-distribution in secondary lymphoid organs as several functionally relevant consequences for the immune response: (1). It leads to the contact-dependent maturation of macrophages, which can limit potential pathogen spreading in secondary lymphoid organs, and of DCs, which relocate to T cell zones and promote downstream adaptive T and B cell responses, resulting in the so-called non-cognate iNKT cell help ( 42 , 55 , 59 62 ); (2). It elicits the secretion of copious amount of different helper cytokines by iNKT cells, which can stimulate innate and adaptive immune effectors throughout the LN and splenic parenchyma ( 60 , 61 ); (3). It results in the acquisition of a follicular helper effector phenotype by iNKT cells (iNKT FH : Bcl6 high CXCR5 high PD-1 high ) ( 57 , 63 , 64 ), which can ultimately enter into the B cell follicles and help CD1d-expressing B cells presenting the same lipid antigen, providing the cognate iNKT cell help ( 56 , 57 , 65 ). In fact, although the interaction with CD1d-expressing B cells is fundamental to sustain the full iNKT FH cell differentiation and functions ( 56 ), the upregulation of the follicular helper molecules by iNKT cells requires the recognition, in first place, of CD1d-expressing myelomonocytic APCs ( 56 ), most likely DCs ( 61 ), but possibly also CD169 + macrophages ( 60 , 62 ). Interestingly, a recent study has gained new mechanistic insight into the critical role of the interaction between LN-resident CD1d + CD169 + macrophages and endogenous iNKT cells for the delivery of non-cognate help to B cells, activated in the course of influenza virus infection ( 28 ). Indeed, as early as 3 days upon influenza virus infection, iNKT cells are found in contact with “ stressed” CD1d + CD169 + macrophages of the subcapsular sinus, in analogy with the results obtained by injecting particulated Ags containing αGalCer. There, iNKT cells become activated by CD169 + macrophages via CD1d-cognate Ag stimulation and secretion of IL-18, without acquiring iNKT FH phenotype. This activation, in turn, induces rapid iNKT cell migration at the B cell follicular border and the secretion of copious IL-4, which is critical for the early phase of germinal center formation and anti-viral antibody responses. Expression of CD1d on macrophages, but not on B cells, is required to elicit IL-4 production by iNKT cells, and mice lacking macrophages or IL-4 develop fewer germinal centers and less influenza specific IgG1 than wild-type mice ( 28 ). It is intriguing that IL-18 release by sinus-lining LN macrophages, induced upon inflammasome-depending pathways activated by pathogen-related innate signals, can also elicit the rapid secretion of protective IFNγ by a network of innate and innate-like effectors that include iNKT cells, which are strategically prepositioned for pathogen sensing in secondary lymphoid organ ( 59 ).

Collectively, these evidences support a critical role for the iNKT/MPS cell axis in the lymphoid system to rapidly sense infections and damage, and immediately react by promoting local and systemic innate and adaptive immune responses.

The Liver

iNKT cells are the prominent T cell subset in the mouse liver, accounting for up to 30% of T lymphocytes. They are also present in the human liver, though at a 30 times lower frequency; nevertheless, both mouse and human hepatic iNKT cells undergo quantitative and qualitative dynamic changes in chronic inflammation/infections or cancer, suggesting active involvement in the pathological processes affecting the organ ( 66 68 ). iNKT cells crawl under basal conditions in liver sinusoids and arrest upon stimulation by cognate antigen recognition, or exposure to inflammatory cytokines IL-12 and/or IL-18 ( 69 71 ). The liver contains a rich monocytic/macrophage component, comprising Kupffer cells, which are self-maintaining, tissue-resident phagocytes originating from embryonic yolk sac, and monocyte-derived macrophages. Kupffer cells and macrophages adjust their phenotypes in response to local signals, which determine their ability to worsen or end liver injury. Both mononuclear phagocyte types express CD1d and can interact with liver iNKT cells, resulting in such functional reprogramming. A paradigm of this function has been highlighted by a recent study using a model of focal hepatic sterile thermal injury assessed by intravital microscopy, revealing that iNKT cells stop and are activated by IL-12, IL-18, and the recognition of self-stress lipid(s) presented by CD1d-expressing CCR2 high Ly6C high inflammatory monocytes migrating into the injured area. Interestingly, the self-lipid(s)+cytokine stimulation results in iNKT cell production of IL-4, but not IFN-γ, which promotes the transition from inflammatory to reparative (CCR2 low Ly6C low CX 3 CR1 high ) monocytes, ultimately leading to the healing of the injury by collagen deposition, wound revascularization and hepatocyte proliferation ( 53 ). Interestingly, human iNKT cells extracted from chronic HBV or HCV infected cirrhotic livers exhibit an IL-4 high /IFNγ low effector profile skewing, compared to iNKT cells from non-chronic viral infections ( 72 ). This is consistent with a pro-fibrotic and tissue repair activity that, in the context of a sustained liver injury, can lead to a pathological form of tissue regeneration. However, in mice, there are also examples of potent IFNγ production by iNKT cells elicited by Kupffer cells during Borrelia burgdorferi liver infections ( 71 ), or upon provoked inflammation and autoimmunity, which promotes M1 polarization of the attracted peritoneal macrophages and, in these cases, sustains tissue damage ( 73 , 74 ). It is possible that the opposite effector responses dominated by IL-4 or IFNγ observed in sterile vs. infectious inflammation may be related also to the different antigenic potency of self vs. bacterial lipid antigens that activate hepatic iNKT cells. Hence, the iNKT cell/MPS crosstalk in the liver is multifaceted depending on the underlying pathological situation, the inflammatory cell type involved, and the weak vs. strong antigen stimulation. All these parameters, collectively, can lead to either tissue repair or damage through the reciprocal modulation of both iNKT cell and macrophage effector functions, even though liver resident iNKT cells are essentially all NKT1 at start. This observation suggests the possibility that the effector profile of liver iNKT cells may change in different pathological situation. As already discussed above, because iNKT cell are reported to be sessile and functionally rigid, an interesting question is whether, under pathological stimuli, liver iNKT cells may either be replaced by newly recruited ones that are endowed with different effector profiles, or undergo functional reprogramming in the organ, implying an unexpected functional plasticity that may apply also to other organs.

The Peritoneum and Omentum

The peritoneum forms a unique microenvironment, which is formed by a thin mesenchymal membrane that lines the abdominal cavity and surrounds the visceral organs. The omentum is a large apron-like peritoneal fold that connects the spleen, pancreas, stomach and transverse colon ( 75 ), which encloses adipocytes and specialized compact structures (“ milky spots”) containing macrophages, DCs, B cells, T cells and mast cells ( 76 ). The omental adipocytes expand in obesity, linking the omentum to the adipose tissue and the metabolic control (see below). The peritoneum is an active immune site, in which both branches of the immune system contribute to maintain homeostasis ( 77 ). In the murine peritoneum, iNKT cells are present in sizable quantity ( 78 ), while the human omentum is highly enriched in iNKT cells, at least 10 time more than any other human organ analyzed ( 34 ). Evidences suggest a close interplay between iNKT cells and the abundant population of CD1d + macrophages found within the peritoneal membrane. iNKT cells negatively correlated with mouse survival in a model of abdominal sepsis ( 79 , 80 ), while induction of abdominal sepsis in the peritoneum of iNKT cell-deficient (Jα18 −/−) mice results in the reduction of Ly6C low anti-inflammatory macrophages and decreased mortality compared to WT. The critical interplay between peritoneal iNKT cells and macrophages is further illustrated by a model of acute sterile inflammation, in which peritoneal macrophages phagocyte neutrophils (efferocytosis) leading to CD1d upregulation and IL-4 secretion. This process activates iNKT cells to produce large amounts of IL-4 that, in concert with the macrophage cytokine, sustains the M2-like polarization and the resolution of the inflammation ( 81 ). In vivo , peritoneal CD4 + iNKT cells are the major producers of IL-4 ( 81 ), suggesting the possibility that peritoneal iNKT cells are either NKT2, or acquire NKT2 phenotype upon stimulation.

The Adipose Tissue

The immune system contained in adipose tissue (AT) is unique. Sizable quantities of innate-like T cells reside in the omentum and visceral AT of mice and humans ( 34 , 82 ). Here, iNKT cells primarily interact with CD1d-expressing macrophages ( 83 ) and adipocytes ( 84 ) to maintain non-inflammatory conditions. In fact, the AT is a sophisticated sensor of metabolic alterations induced by dietary stimuli, and the status of AT-resident macrophages is of great importance for the physiological metabolic control at this site: pathological metabolic alterations associated with obesity results in profound modification of AT-macrophages, inducing pro-inflammatory (M1-like) functions and a consequent increase in local inflammation and insulin resistance ( 35 , 85 ). Regulatory iNKT10 cells are selectively enriched in the AT and rapidly respond to stimulatory lipids presented by CD1d+ macrophages, or adipocytes, by secreting IL-4 that restrains M1 and promotes M2 polarization ( 25 , 35 , 83 , 85 , 86 ). However, a prolonged dysmetabolic state provokes down-regulation of CD1d on AT-M2 cells and their switch to an M1-like phenotype that, in turn, leads also to a pro-inflammatory shift of local iNKT cells ( 83 , 87 , 88 ), again suggesting a plasticity due to the migration of iNKT1 cells from other sites or a functional differentiation of local cells. The presence of iNKT cells in the AT, which is conserved between mouse and human, is crucial for the formation of fat-associated lymphoid clusters (FALC). FALC are non-capsulated structures in the adipose tissue that collect T H 2-skewed immune cells, most notably ILC2 ( 89 ), which direct the polarization of B1 cells, eosinophils and M2 macrophages ( 90 ) in order to maintain the homeostasis in the tissue. FALC are absent in CD1d −/− mice, while they can be induced following iNKT cell adoptive transfer in Rag2 −/−, suggesting the critical dependency of these structures on iNKT cells ( 91 ). Under peritoneal inflammation, the activation of iNKT cells increases the formation of FALC, indirectly inducing the recruitment of beneficial anti-inflammatory myeloid cells and the resolution of inflammation.

The Gastro-intestinal System

In mice, under homeostatic conditions, gut infiltrating iNKT cells (small intestine and lamina propria) are NKT1 (> 90%) or NKT17 (<10%) ( 92 ). NKT2 are barely detectable in the intestinal epithelium, although they represent up to 40% of iNKT cells of the mesenteric lymph node (LN) and of those infiltrating Peyer’s Patches ( 24 ). The accumulation of iNKT cells in the small intestine and mesenteric LN has been confirmed also in humans ( 30 ). Intestinal macrophages maintain gut homeostasis through the clearance of enteric pathogens and the enforcement of the tolerance to food and microbiota antigens via the production of IL-10 ( 93 , 94 ). Recent evidences point out that a heterogeneous CD11c + myeloid population, which includes both DCs and macrophages, stimulate iNKT cells in the gastro-intestinal system ( 92 ), resulting in the control of the intestinal bacteria composition and compartmentalization, regulation of the IgA repertoire and induction of regulatory T cells within the gut. The recognition of microbial lipid products is pivotal for the physiology of intestinal iNKT cells ( 95 97 ). In this context, α-glycolipids that are recognized from iNKT cells can originate from the commensal flora ( 98 , 99 ), or from the diet ( 100 ). Upon CD11c + myeloid cell-activation, NKT17 and NKT2 cells in the mesenteric LN undergo rapid activation and expansion, suggesting a pathogenic role for these cells in ulcerative colitis ( 101 ).

The Lungs

In the steady state, the mouse lung contains iNKT cells that distribute predominantly in the vasculature, with a minority residing in the interstitium, which are belong to clearly distinct functional subsets. Whereas the majority of the lung-associated vasculature cells are NKT1, the lung interstitium contains the highest frequency of NKT17 in C57BL6 mice (> 50%) ( 24 , 102 ), which is consistent with their involvement in pathogen surveillance. Barrier epithelia (e. g., lungs, colon, skin, LN) produce elevated quantitates of IL-7 ( 103 ) which drives NKT17 survival and maintenance ( 104 ), thus creating a microenvironment favorable for the accumulation of these effector cells. The clearance of inhaled pathogen is the main feature of lung-resident (alveolar) macrophages ( 51 ). The iNKT cell-macrophages axis is once again critical in this context. In a model of viral-induced chronic airway inflammation, iNKT cells are directly recruiting and activating macrophages toward an anti-inflammatory, tissue remodeling M2-state ( 105 ). Increased amounts of iNKT cells and of IL-13 producing macrophages have been detected not only in mice, but also in patients with chronic obstructive pulmonary disease (COPD) ( 105 , 106 ), supporting the involvement of the iNKT cell/macrophage crosstalk in the lung pathophysiology.

iNKT cells react also to a number of pathogens involved in airway infections, including Sphingomonas capsulata ( 107 ), Mycobacterium tuberculosis ( 108 ), Pseudomonas aeruginosa ( 109 , 110 ), Streptococcus pneumoniae ( 111 ) and Influenza A virus ( 112 , 113 ), via involvement of local mononuclear phagocytic cells, particularly macrophages. During M. tuberculosis infection in mice, iNKT cells are activated upon interaction with macrophages presenting mycobacterium-specific lipids ( 108 ) and help controlling the bacterial load via GM-CSF production ( 114 ), which may promote an inflammatory response that ultimately leads to bacterial clearance. A similar mechanism has been identified for P. aeruginosa , where iNKT cells stimulate increased phagocytic clearance of the bacteria in the lung by alveolar macrophages ( 109 ). Interestingly, in this context, iNKT cells have a stronger effect in controlling P. aeruginosa in BALB/c compared to C57BL6 mice ( 110 ). This difference can be explained by the different iNKT cell subsets that infiltrate the lungs of the two strains, as BALB/c mice contain an higher frequency of NKT1 subset compared to C57BL6 ( 24 , 115 ). In the case of S. Pneumonia infection, intravital microscopy reveals that interstitial DCs present microbial glycolipids to the few adjacent iNKT cells, resulting in the neutrophil recruitment and CCL17 production. This promotes further iNKT cell migration from vasculature into acutely inflamed lung interstitium, where they assist DC activation and clearance of infection ( 116 ). This mechanism for acute inflammation seems conserved also in humans, as suggested by the human iNKT cell ability to drive in vitro the release inflammatory lipid mediators by monocyte-derived DCs, which can promote neutrophil recruitment and activation ( 48 ).

In addition to controlling bacterial infections, iNKT cells were also active in containing pulmonary infection influenza A virus. In this context, iNKT cells orchestrate anti-viral NK and CD8 + T cell responses ( 113 , 117 119 ). iNKT cells promote virus control also by promoting differentiation into functional APC of lung-infiltrating immature myeloid derived cells, through CD40 engagement and CD1d cognate recognition ( 17 ), or by reducing pathogenic inflammatory monocytes (Ly6C high Ly6G ) via direct lysis ( 112 ), which correlates with better influenza outcome in iNKT cell-sufficient compared to insufficient mice.

The Tumor Microenvironment

Cancer cells are embedded in the tumor microenvironment (TME), a complex and active milieu in which transformed and non-transformed cells dynamically interact in evolving networks that are continuously rearranged ( 120 ). The composition of the TME impinges heavily on the success of cancer therapy, and many studies underline the importance of targeting both the tumor and the supporting stroma for an effective and complete clearance of the malignancy ( 121 ). A substantial fraction of immune infiltrate of the TME is composed by tumor associated macrophages (TAMs) ( 122 ), which can encompass a spectrum of activation states largely affecting tumor progression, dissemination and response to therapy ( 36 ). Different stimuli present in the microenvironment can also rapidly trigger a number of diverse functions in macrophages, which range from the activation of potent pro-inflammatory M1-like responses, to the coordination of M2-like tissue remodeling and immunosuppression.

Despite their low numbers, iNKT cells are also components of the immune infiltrate present in both mouse and human tumors ( 26 , 78 , 123 125 ). Indeed, a growing body of evidences lends support to a critical role for these cells in modulating myelomonocytic cells in the tumor microenvironment. M1-oriented TAMs are generally beneficial for the control of tumors because by exerting critical functions such as antigen presentation, production of inflammatory cytokines and inhibition of angiogenesis ( 126 , 127 ). By contrast, M2-like TAMs are detrimental, because they exert tumor-supporting, pro-angiogenic, pro-metastatic, and immunosuppressive activities ( 128 ). The first hints of iNKT cells interplay with TAMs come from the observation that these cells can kill in a CD1d-dependent manner transferred human macrophages infiltrating a xenograft model of human neuroblastoma in NOD/ SCID/IL-2Rγ-null (NSG) mice ( 129 ). The importance of the iNKT cell-TAM crosstalk is further strengthen in the same model, by showing that iNKT cells are recruited into tumor in a CCL20-dependent manner, but inhibited in their anti-tumor activity by macrophage-induced hypoxia ( 125 ). In the recent years, this dual relationship has been investigated more in detail. By using a mouse model of oncogene-induced pancreatic cancer, iNKT cells have been shown to have a preferential activity on M2-like macrophages, which are increased in CD1d −/− pancreatic cancers ( 130 ). iNKT cells delay also the onset and organ infiltration of a mouse model of chronic lymphocytic leukemia (CLL), and their counts in blood independently predicts disease stability in CLL patients ( 78 ). iNKT cells remodel the supporting niche of CLL by controlling CD1d-expressing, patient-derived M2-like macrophage population, termed nurse-like cells (NLCs), which sustain leukemia cell survival ( 78 , 131 ). The unique mechanism by which iNKT cells selectively modulate different subset of TAMs has been recently elucidated in a model of autochthonous prostate cancer ( 26 ). In this model, the presence of iNKT cells causally associates with the selective reduction of M2-like TAMs in the tumor microenvironment, leading to the control of tumor progression. Human prostate cancer aggressiveness correlates with reduced intra-tumoral iNKT cells and increased M2 macrophages, underscoring the clinical significance of this crosstalk ( 26 ). This selective restriction of M2 TAMs depends on the combinatorial engagement of CD40 and Fas on the surface of macrophages by tumor-infiltrating iNKT cells. Although both molecules are expressed to similar levels on either M1 or M2 TAM populations, the CD40L-CD40 pathway supported the survival only of the M1 population, likely by antagonizing the apoptotic death driven by Fas signaling. By contrast, CD40 expression does not protect M2 TAMs form FAS-dependent killing, suggesting a differential CD40 signaling between M1 and M2 macrophages. Remarkably, the ability to selectively eliminating pro-tumor M2 macrophages seems, thus far, unique to iNKT cells. Interestingly, however, a mouse transgenic model of colon adenocarcinoma represents an exception to this general mechanism. Here, iNKT cells support pre-malignant progression by suppressing T H 1 responses, and promoting suppressive Treg and M2-polarization of TAMs, leading to increased intestinal adenomatous polyps formation ( 132 ). The dichotomous iNKT cell response in the two mouse tumor models may be related to changes undergoing in the different TMEs. In both healthy prostate and intestine tissues, the NKT1 and NKT17 are mostly represented. However, as tumor progresses, iNKT cells infiltrating intestinal polyps start to produce IL-10, while those in the prostate cancer setting remained T H 1-oriented.

On the basis of the described evidences, it is tempting to speculate that tumor-infiltrating iNKT cells lead the immune reprogramming of the local TME by acting primarily on the MPS. This remodeling activity in the tumor context appears critically determined by the specific effector profile exhibited by iNKT cells in the target tissue in physiological conditions, before the development of the malignancy. It will be important to investigate such relationship in different cancers, particularly human ones, given also the interest to define possible different tissue resident iNKT cell subsets, as well as to harness these cells for cancer immunotherapy that exploits their unique potential to reprogram the tumor microenvironment.

Challenges and Future Directions

Increasing evidence underscore the relevance of the iNKT cell/mononuclear phagocyte crosstalk in many different tissues, which may contribute to the induction, or the resolution, of tissue damage depending on the local effector phenotype exhibited by the two cell types interacting in the specific tissue. To this respect, iNKT cells are widely located in, non-lymphoid tissues in homeostatic conditions, at least in mice, which include (but are not limited to) the central nervous system ( 133 ), kidney ( 134 , 135 ), eye ( 136 ), placenta ( 137 ), pancreas ( 138 ), and prostate ( 26 ). In all these sites, iNKT cells have the possibility of interacting, or have been suggested to interact, with tissue-resident MPS cells. However, the result of this crosstalk has not yet fully elucidated. In some cases, iNKT cells and resident mononuclear phagocytic cells show complementary functions. During acute kidney injury, iNKT cells alleviate the induced damages in different models ( 135 , 139 141 ). Interestingly, these pathological conditions are highly dependent on renal macrophages, that switch between M1 and M2 phenotype during the acute or the tissue-repair phase ( 142 ), or on immature DCs ( 135 ), suggesting a link with NKT1 or NKT2 cells. In the eye, iNKT cells contribute to the natural tolerance occurring at this site ( 136 ) by cross-talking with T cells, neutrophils and macrophages ( 143 ). During reproduction, iNKT cells are present in the placenta, the interface between the mother and the fetus ( 144 ), and play role in orchestrating the immune response during infections occurring during pregnancy ( 145 ). Considering that iNKT cells consistently infiltrate the placenta also in healthy pregnancies ( 137 ), it is reasonable to hypothesize that their role is not limited to pathological conditions but they constantly support the reproduction process, for instance maintaining the status of tolerance induced by IL-10 producing macrophages ( 146 ). In the pancreas, iNKT cells promote an innate response against LCMV, by enhancing the local recruitment of pDCs and stimulating their production of anti-viral type I IFNs via OX40-OX40L interaction ( 138 ). However, CD1d expression by pDCs is not required for this interaction, suggesting a different, yet undefined, mechanism from those described in other tissues. Given the long standing implication of iNKT cells in the control of Type 1 Diabetes, it would be interesting to assess whether and by what mechanisms these cells may modulate MPS cells in the pancreas ( 147 ).

Some of the signals controlling the meeting between the two cell types have been defined, however this remains an open area to explore. Mouse and human iNKT cells express chemokine receptor pattern typical of trafficking toward inflammation sites ( 148 151 ) which overlaps at least in part with that of monocytes, supporting a cooperative engagement at inflammatory sites. Indeed, it has been shown that following B. burgdorferi infection Kupffer cells induce CXCR3-dependent clustering of iNKT cells ( 71 ), while CXCR6 drives homeostatic iNKT localization in liver sinusoids ( 69 ). A final big gap in knowledge concerns details on the presence of different iNKT cell subsets in different human tissues and their possible interaction with MPS cells. Correlative studies suggest undergoing crosstalk between the two cell types also in human tissues, although direct evidence is substantially lacking. A more precise definition of these mechanisms, focusing in particular on the human system in physiology and pathology, should drive future studies.

Concluding Remarks

The crosstalk between iNKT cells and cells of the MPS has a critical role in both physiological and pathological conditions. The outcome of this interaction is highly dependent on the tissue where it occurs and can be either beneficial or detrimental for the host. Harnessing this crosstalk has potential therapeutic relevance in different pathologies, from cancer to infections, chronic inflammatory diseases or metabolic disorders, as well as to improve vaccine formulation.

Author Contributions

All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.

Conflict of Interest Statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Acknowledgments

We thank the reviewers for their insightful comments and helpful suggestions. This study is supported by a personal fellowship from the Italian Association for Cancer Research (AIRC) to FC (2015-18316), and grants AIRC IG-20081 to GC and LYRA Fondazione Regionale per la Ricerca Biomedica-FRRB to PD.

References

1. Salio M, Silk JD, Jones EY, Cerundolo V. Biology of CD1- and MR1-restricted T cells. Annu Rev Immunol.(2014) 32: 323–66. doi: 10. 1146/annurev-immunol-032713-120243

||

2. Dellabona P, Padovan E, Casorati G, Brockhaus M, Lanzavecchia A. An invariant V alpha 24-J alpha Q/V beta 11 T cell receptor is expressed in all individuals by clonally expanded CD4-8- T cells. J Exp Med.(1994) 180: 1171–6. doi: 10. 1084/jem. 180. 3. 1171

||

3. Lantz O, Bendelac A. An invariant T cell receptor alpha chain is used by a unique subset of major histocompatibility complex class I-specific CD4+ and CD4-8- T cells in mice and humans. J Exp Med.(1994) 180: 1097–106. doi: 10. 1084/jem. 180. 3. 1097

||

4. Godfrey DI, Macdonald HR, Kronenberg M, Smyth MJ, Van Kaer L. NKT cells: what’s in a name? Nat Rev Immunol.(2004) 4: 231–7. doi: 10. 1038/nri1309

||

5. Dasgupta S, Kumar V. Type II NKT cells: a distinct CD1d-restricted immune regulatory NKT cell subset. Immunogenetics (2016) 68: 665–76. doi: 10. 1007/s00251-016-0930-1

||

6. Kawano T, Cui J, Koezuka Y, Toura I, Kaneko Y, Motoki K, et al. CD1d-restricted and TCR-mediated activation of valpha14 NKT cells by glycosylceramides. Science (1997) 278: 1626–9. doi: 10. 1126/science. 278. 5343. 1626

||

7. Coquet JM, Chakravarti S, Kyparissoudis K, McNab FW, Pitt LA, McKenzie BS, et al. Diverse cytokine production by NKT cell subsets and identification of an IL-17-producing CD4-NK1. 1- NKT cell population. Proc Natl Acad Sci USA.(2008) 105: 11287–92. doi: 10. 1073/pnas. 0801631105

||

8. Leite-de-Moraes MC, Herbelin A, Gouarin C, Koezuka Y, Schneider E, Dy M. Fas/Fas ligand interactions promote activation-induced cell death of NK T lymphocytes. J Immunol.(2000) 165: 4367–71. doi: 10. 4049/jimmunol. 165. 8. 4367

||

9. Nagarajan NA, Kronenberg M. Invariant NKT cells amplify the innate immune response to lipopolysaccharide. J Immunol.(2007) 178: 2706–13. doi: 10. 4049/jimmunol. 178. 5. 2706

||

10. Vincent MS, Leslie DS, Gumperz JE, Xiong X, Grant EP, Brenner MB. CD1-dependent dendritic cell instruction. Nat Immunol.(2002) 3: 1163–8. doi: 10. 1038/ni851

||

11. Fox LM, Cox DG, Lockridge JL, Wang X, Chen X, Scharf L, et al. Recognition of lyso-phospholipids by human natural killer T lymphocytes. PloS Biol.(2009) 7: e1000228. doi: 10. 1371/journal. pbio. 1000228

||

12. Darmoise A, Teneberg S, Bouzonville L, Brady RO, Beck M, Kaufmann SH, et al. Lysosomal alpha-galactosidase controls the generation of self lipid antigens for natural killer T cells. Immunity (2010) 33: 216–28. doi: 10. 1016/j. immuni. 2010. 08. 003

||

13. Hegde S, Lockridge JL, Becker YA, Ma S, Kenney SC, Gumperz JE. Human NKT cells direct the differentiation of myeloid APCs that regulate T cell responses via expression of programmed cell death ligands. J Autoimmun.(2011) 37: 28–38. doi: 10. 1016/j. jaut. 2011. 03. 001

||

14. Wingender G, Hiss M, Engel I, Peukert K, Ley K, Haller H, Kronenberg M, et al. Neutrophilic granulocytes modulate invariant NKT cell function in mice and humans. J Immunol.(2012) 188: 3000–8. doi: 10. 4049/jimmunol. 1101273

||

15. Keller CW, Freigang S, Lünemann JD. Reciprocal crosstalk between dendritic cells and natural killer T cells: mechanisms and therapeutic potential. Front Immunol.(2017) 8: 570. doi: 10. 3389/fimmu. 2017. 00570

||

16. Gillessen S, Naumov YN, Nieuwenhuis EE, Exley MA, Lee FS, Mach N, et al. CD1d-restricted T cells regulate dendritic cell function and antitumor immunity in a granulocyte-macrophage colony-stimulating factor-dependent fashion. Proc Natl Acad Sci USA.(2003) 100: 8874–9. doi: 10. 1073/pnas. 1033098100

||

17. De Santo C, Salio M, Masri SH, Lee LY, Dong T, Speak AO, et al. Invariant NKT cells reduce the immunosuppressive activity of influenza A virus-induced myeloid-derived suppressor cells in mice and humans. J Clin Invest.(2008) 118: 4036–48. doi: 10. 1172/JCI36264

||

18. Renukaradhya GJ, Khan MA, Vieira M, Du W, Gervay-Hague J, Brutkiewicz RR. Type I NKT cells protect (and type II NKT cells suppress) the host’s innate antitumor immune response to a B-cell lymphoma. Blood (2008) 111: 5637–45. doi: 10. 1182/blood-2007-05-092866

||

19. Hegde S, Fox L, Wang X, Gumperz JE. Autoreactive natural killer T cells: promoting immune protection and immune tolerance through varied interactions with myeloid antigen-presenting cells. Immunology (2010) 130: 471–83. doi: 10. 1111/j. 1365-2567. 2010. 03293. x

||

20. Merad M, Sathe P, Helft J, Miller J, Mortha A. The dendritic cell lineage: ontogeny and function of dendritic cells and their subsets in the steady state and the inflamed setting. Annu Rev Immunol.(2013) 31: 563–604. doi: 10. 1146/annurev-immunol-020711-074950

||

21. Ginhoux F, Jung S. Monocytes and macrophages: developmental pathways and tissue homeostasis. Nat Rev Immunol.(2014) 14: 392–404. doi: 10. 1038/nri3671

||

22. Varol C, Mildner A, Jung S. Macrophages: development and tissue specialization. Annu Rev Immunol.(2015) 33: 643–75. doi: 10. 1146/annurev-immunol-032414-112220

||

23. Thomas SY, Scanlon ST, Griewank KG, Constantinides MG, Savage AK, Barr KA, et al. PLZF induces an intravascular surveillance program mediated by long-lived LFA-1-ICAM-1 interactions. J Exp Med.(2011) 208: 1179–88. doi: 10. 1084/jem. 20102630

||

24. Lee YJ, Wang H, Starrett GJ, Phuong V, Jameson SC, Hogquist KA. Tissue-specific distribution of iNKT cells impacts their cytokine response. Immunity (2015) 43: 566–78. doi: 10. 1016/j. immuni. 2015. 06. 025

||

25. Lynch L, Michelet X, Zhang S, Brennan PJ, Moseman A, Lester C, et al. Regulatory iNKT cells lack expression of the transcription factor PLZF and control the homeostasis of T(reg) cells and macrophages in adipose tissue. Nat Immunol.(2015) 16: 85–95. doi: 10. 1038/ni. 3047

||

26. Cortesi F, Delfanti G, Grilli A, Calcinotto A, Gorini F, Pucci F, et al. Bimodal CD40/Fas-Dependent Crosstalk between iNKT cells and tumor-associated macrophages impairs prostate cancer progression. Cell Rep.(2018) 22: 3006–20. doi: 10. 1016/j. celrep. 2018. 02. 058

||

27. Cameron G, Godfrey DI. Differential surface phenotype and context-dependent reactivity of functionally diverse NKT cells. Immunol Cell Biol.(2018). doi: 10. 1111/imcb. 12034. [Epub ahead of print].

||

28. Gaya M, Barral P, Burbage M, Aggarwal S, Montaner B, Navia AW, et al. Initiation of antiviral B cell immunity relies on innate signals from spatially positioned NKT cells. Cell (2018) 172: 517–20. e20. doi: 10. 1016/j. cell. 2017. 11. 036

||

29. Lee YJ, Holzapfel KL, Zhu J, Jameson SC, Hogquist KA. Steady-state production of IL-4 modulates immunity in mouse strains and is determined by lineage diversity of iNKT cells. Nat Immunol.(2013) 14: 1146–54. doi: 10. 1038/ni. 2731

||

30. Loh L, Ivarsson MA, Michaëlsson J, Sandberg JK, Nixon DF. Invariant natural killer T cells developing in the human fetus accumulate and mature in the small intestine. Mucosal Immunol.(2014) 7: 1233–43. doi: 10. 1038/mi. 2014. 13

||

31. Vieth JA, Das J, Ranaivoson FM, Comoletti D, Denzin LK, Sant’Angelo DB. TCRα-TCRβ pairing controls recognition of CD1d and directs the development of adipose NKT cells. Nat Immunol.(2016) 18: 36–44. doi: 10. 1038/ni. 3622

||

32. Engel I, Seumois G, Chavez L, Samaniego-Castruita D, White B, Chawla A, et al. Innate-like functions of natural killer T cell subsets result from highly divergent gene programs. Nat Immunol.(2016) 17: 728–39. doi: 10. 1038/ni. 3437

||

33. Hashimoto D, Chow A, Noizat C, Teo P, Beasley MB, Leboeuf M, et al. Tissue-resident macrophages self-maintain locally throughout adult life with minimal contribution from circulating monocytes. Immunity (2013) 38: 792–804. doi: 10. 1016/j. immuni. 2013. 04. 004

||

34. Lynch L, O’Shea D, Winter DC, Geoghegan J, Doherty DG, O’Farrelly C. Invariant NKT cells and CD1d(+) cells amass in human omentum and are depleted in patients with cancer and obesity. Eur J Immunol.(2009) 39: 1893–901. doi: 10. 1002/eji. 200939349

||

35. Lynch L, Nowak M, Varghese B, Clark J, Hogan AE, Toxavidis V, et al. Adipose tissue invariant NKT cells protect against diet-induced obesity and metabolic disorder through regulatory cytokine production. Immunity (2012) 37: 574–87. doi: 10. 1016/j. immuni. 2012. 06. 016

||

36. Mantovani A, Sozzani S, Locati M, Allavena P, Sica A. Macrophage polarization: tumor-associated macrophages as a paradigm for polarized M2 mononuclear phagocytes. Trends Immunol.(2002) 23: 549–55. doi: 10. 1016/S1471-4906(02)02302-5

||

37. Mosser DM, Edwards JP. Exploring the full spectrum of macrophage activation. Nat Rev Immunol.(2008) 8: 958–69. doi: 10. 1038/nri2448

||

38. Xue J, Schmidt SV, Sander J, Draffehn A, Krebs W, Quester I, et al. Transcriptome-based network analysis reveals a spectrum model of human macrophage activation. Immunity (2014) 40: 274–88. doi: 10. 1016/j. immuni. 2014. 01. 006

||

39. Murray PJ, Allen JE, Biswas SK, Fisher EA, Gilroy DW, Goerdt S, et al. Macrophage activation and polarization: nomenclature and experimental guidelines. Immunity (2014) 41: 14–20. doi: 10. 1016/j. immuni. 2014. 06. 008

||

40. Zimmer MI, Colmone A, Felio K, Xu H, Ma A, Wang CR. A cell-type specific CD1d expression program modulates invariant NKT cell development and function. J Immunol.(2006) 176: 1421–30. doi: 10. 4049/jimmunol. 176. 3. 1421

||

41. Napolitano A, Pittoni P, Beaudoin L, Lehuen A, Voehringer D, Macdonald HR, et al. Functional education of invariant NKT cells by dendritic cell tuning of SHP-1. J Immunol.(2013) 190: 3299–308. doi: 10. 4049/jimmunol. 1203466

||

42. Hermans IF, Silk JD, Gileadi U, Salio M, Mathew B, Ritter G, et al. NKT cells enhance CD4+ and CD8+ T cell responses to soluble antigen in vivo through direct interaction with dendritic cells. J Immunol.(2003) 171: 5140–7. doi: 10. 4049/jimmunol. 171. 10. 5140

||

43. Münz C, Steinman RM, Fujii SI. Dendritic cell maturation by innate lymphocytes: coordinated stimulation of innate and adaptive immunity. J Exp Med.(2005) 202: 203–7. doi: 10. 1084/jem. 20050810

||

44. Yue SC, Shaulov A, Wang R, Balk SP, Exley MA. CD1d ligation on human monocytes directly signals rapid NF-kappaB activation and production of bioactive IL-12. Proc Natl Acad Sci USA.(2005) 102: 11811–6. doi: 10. 1073/pnas. 0503366102

||

45. Fujii SI, Shimizu K, Kronenberg M, Steinman RM. Prolonged IFN-gamma-producing NKT response induced with alpha-galactosylceramide-loaded DCs. Nat Immunol.(2002) 3: 867–74. doi: 10. 1038/ni827

||

46. Fujii SI, Liu K, Smith C, Bonito AJ, Steinman RM. The linkage of innate to adaptive immunity via maturing dendritic cells in vivo requires CD40 ligation in addition to antigen presentation and CD80/86 costimulation. J Exp Med.(2004) 199: 1607–18. doi: 10. 1084/jem. 20040317

||

47. Liu K, Idoyaga J, Charalambous A, Fujii SI, Bonito A, Mordoh J, et al. Innate NKT lymphocytes confer superior adaptive immunity via tumor-capturing dendritic cells. J Exp Med.(2005) 202: 1507–16. doi: 10. 1084/jem. 20050956

||

48. Xu X, Pocock GM, Sharma A, Peery SL, Fites JS, Felley L, et al. Human iNKT cells promote protective inflammation by inducing oscillating purinergic signaling in monocyte-derived DCs. Cell Rep.(2016) 16: 3273–85. doi: 10. 1016/j. celrep. 2016. 08. 061

||

49. Felley LE, Sharma A, Theisen E, Romero-Masters JC, Sauer JD, Gumperz JE. Human invariant NKT cells induce IL-1β secretion by peripheral blood monocytes via a P2X7-independent pathway. J Immunol.(2016) 197: 2455–64. doi: 10. 4049/jimmunol. 1600790

||

50. Hegde S, Jankowska-Gan E, Roenneburg DA, Torrealba J, Burlingham WJ, Gumperz JE. Human NKT cells promote monocyte differentiation into suppressive myeloid antigen-presenting cells. J Leukoc Biol.(2009) 86: 757–68. doi: 10. 1189/jlb. 0209059

||

51. Murray PJ, Wynn TA. Protective and pathogenic functions of macrophage subsets. Nat Rev Immunol.(2011) 11: 723–37. doi: 10. 1038/nri3073

||

52. Wu D, Shi Y, Wang C, Chen H, Liu Q, Liu J, et al. Activated NKT cells facilitated functional switch of myeloid-derived suppressor cells at inflammation sites in fulminant hepatitis mice. Immunobiology (2017) 222: 440–9. doi: 10. 1016/j. imbio. 2016. 08. 005

||

53. Liew PX, Lee WY, Kubes P. iNKT cells orchestrate a switch from inflammation to resolution of sterile liver injury. Immunity (2017) 47: 752–65. e5. doi: 10. 1016/j. immuni. 2017. 09. 016

||

54. Barral P, Eckl-Dorna J, Harwood NE, De Santo C, Salio M, Illarionov P, et al. B cell receptor-mediated uptake of CD1d-restricted antigen augments antibody responses by recruiting invariant NKT cell help in vivo . Proc Natl Acad Sci USA.(2008) 105: 8345–50. doi: 10. 1073/pnas. 0802968105

||

55. Tonti E, Galli G, Malzone C, Abrignani S, Casorati G, Dellabona P. NKT-cell help to B lymphocytes can occur independently of cognate interaction. Blood (2009) 113: 370–6. doi: 10. 1182/blood-2008-06-166249

||

56. Chang P-P, Barral P, Fitch J, Pratama A, Ma CS, Kallies A, et al. Identification of Bcl-6-dependent follicular helper NKT cells that provide cognate help for B cell responses. Nat Immunol.(2011) 13: 35–43. doi: 10. 1038/ni. 2166

||

57. Tonti E, Fedeli M, Napolitano A, Iannacone M, Andrian von UH, Guidotti LG, et al. Follicular helper NKT cells induce limited B cell responses and germinal center formation in the absence of CD4(+) T cell help. J Immunol.(2012) 188: 3217–22. doi: 10. 4049/jimmunol. 1103501

|

58. Dellabona P, Abrignani S, Casorati G. iNKT-cell help to B cells: a cooperative job between innate and adaptive immune responses. Eur J Immunol.(2014) 44: 2230–7. doi: 10. 1002/eji. 201344399

||

59. Kastenmüller W, Torabi-Parizi P, Subramanian N, Lämmermann T, Germain RN. A spatially-organized multicellular innate immune response in lymph nodes limits systemic pathogen spread. Cell (2012) 150: 1235–48. doi: 10. 1016/j. cell. 2012. 07. 021

||

60. Barral P, Polzella P, Bruckbauer A, van Rooijen N, Besra GS, Cerundolo V, et al. CD169(+) macrophages present lipid antigens to mediate early activation of iNKT cells in lymph nodes. Nat Immunol.(2010) 11: 303–12. doi: 10. 1038/ni. 1853

||

61. King IL, Amiel E, Tighe M, Mohrs K, Veerapen N, Besra G, et al. The mechanism of splenic invariant NKT cell activation dictates localization in vivo . J Immunol.(2013) 191: 572–82. doi: 10. 4049/jimmunol. 1300299

||

62. Barral P, Sánchez-Niño MD, van Rooijen N, Cerundolo V, Batista FD. The location of splenic NKT cells favours their rapid activation by blood-borne antigen. EMBO J.(2012) 31: 2378–90. doi: 10. 1038/emboj. 2012. 87

||

63. Leadbetter EA, Brigl M, Illarionov P, Cohen N, Luteran MC, Pillai S, et al. NK T cells provide lipid antigen-specific cognate help for B cells. Proc Natl Acad Sci USA.(2008) 105: 8339–44. doi: 10. 1073/pnas. 0801375105

||

64. Vinuesa CG, Chang PP. Innate B cell helpers reveal novel types of antibody responses. Nat Immunol.(2013) 14: 119–26. doi: 10. 1038/ni. 2511

||

65. King IL, Fortier A, Tighe M, Dibble J, Watts GF, Veerapen N, et al. Invariant natural killer T cells direct B cell responses to cognate lipid antigen in an IL-21-dependent manner. Nat Immunol . (2011) 13: 44–50. doi: 10. 1038/ni. 2172

||

66. Exley MA, Tahir SM, Cheng O, Shaulov A, Joyce R, Avigan D, et al. Cutting edge: a major fraction of human bone marrow lymphocytes are Th2-Like CD1d-reactive T cells that can suppress mixed lymphocyte responses. J Immunol.(2001) 167: 5531–4. doi: 10. 4049/jimmunol. 167. 10. 5531

||

67. Bricard G, Cesson V, Devevre E, Bouzourene H, Barbey C, Rufer N, et al. Enrichment of human CD4+ V 24/V 11 invariant NKT cells in intrahepatic malignant tumors. J Immunol.(2009) 182: 5140–51. doi: 10. 4049/jimmunol. 0711086

||

68. de Lalla C, Rinaldi A, Montagna D, Azzimonti L, Bernardo ME, Sangalli LM, et al. Invariant NKT cell reconstitution in pediatric leukemia patients given HLA-haploidentical stem cell transplantation defines distinct CD4+ and CD4- subset dynamics and correlates with remission state. J Immunol.(2011) 186: 4490–9. doi: 10. 4049/jimmunol. 1003748

||

69. Geissmann F, Cameron TO, Sidobre S, Manlongat N, Kronenberg M, Briskin MJ, et al. Intravascular immune surveillance by CXCR6+ NKT cells patrolling liver sinusoids. PloS Biol.(2005) 3: e113. doi: 10. 1371/journal. pbio. 0030113

||

70. Velazquez P, Cameron TO, Kinjo Y, Nagarajan N, Kronenberg M, Dustin ML. Cutting edge: activation by innate cytokines or microbial antigens can cause arrest of natural killer T cell patrolling of liver sinusoids. J Immunol.(2008) 180: 2024–8. doi: 10. 4049/jimmunol. 180. 4. 2024

||

71. Lee WY, Moriarty TJ, Wong CH, Zhou H, Strieter RM, van Rooijen N, et al. An intravascular immune response to Borrelia burgdorferi involves Kupffer cells and iNKT cells. Nat Immunol.(2010) 11: 295–302. doi: 10. 1038/ni. 1855

||

72. de Lalla C, Galli G, Aldrighetti L, Romeo R, Mariani M, Monno A, et al. Production of profibrotic cytokines by invariant NKT cells characterizes cirrhosis progression in chronic viral hepatitis. J Immunol.(2004) 173: 1417–25. doi: 10. 4049/jimmunol. 173. 2. 1417

||

73. Chuang YH, Lian ZX, Yang GX, Shu SA, Moritoki Y, Ridgway WM, et al. Natural killer T cells exacerbate liver injury in a transforming growth factor β receptor II dominant-negative mouse model of primary biliary cirrhosis. Hepatology (2007) 47: 571–80. doi: 10. 1002/hep. 22052

||

74. Park O, Jeong WI, Wang L, Wang H, Lian ZX, Gershwin ME, et al. Diverse roles of invariant natural killer T cells in liver injury and fibrosis induced by carbon tetrachloride. Hepatology (2008) 49: 1683–94. doi: 10. 1002/hep. 22813

||

75. Platell C, Cooper D, Papadimitriou JM, Hall JC. The omentum. World J Gastroenterol.(2000) 6: 169–76. doi: 10. 3748/wjg. v6. i2. 169

||

76. Shimotsuma M, Takahashi T, Kawata M, Dux K. Cellular subsets of the milky spots in the human greater omentum. Cell Tissue Res.(1991) 264: 599–601. doi: 10. 1007/BF00319049

||

77. Capobianco A, Cottone L, Monno A, Manfredi AA, Rovere-Querini P. The peritoneum: healing, immunity, and diseases. J Pathol.(2017) 243: 137–47. doi: 10. 1002/path. 4942

||

78. Gorini F, Azzimonti L, Delfanti G, Scarfò L, Scielzo C, Bertilaccio MT, et al. Invariant NKT cells contribute to chronic lymphocytic leukemia surveillance and prognosis. Blood (2017) 129: 3440–51. doi: 10. 1182/blood-2016-11-751065

||

79. Hu CK, Venet F, Heffernan DS, Wang YL, Horner B, Huang X, et al. The role of hepatic invariant NKT cells in systemic/local inflammation and mortality during polymicrobial septic shock. J Immunol.(2009) 182: 2467–75. doi: 10. 4049/jimmunol. 0801463

||

80. Fallon EA, Chun TT, Young WA, Gray C, Ayala A, Heffernan DS. Program cell death receptor-1-mediated invariant natural killer T-cell control of peritoneal macrophage modulates survival in neonatal sepsis. Front Immunol.(2017) 8: 1469. doi: 10. 3389/fimmu. 2017. 01469

||

81. Zeng MY, Pham D, Bagaitkar J, Liu J, Otero K, Shan M, et al. An efferocytosis-induced, IL-4-dependent macrophage-iNKT cell circuit suppresses sterile inflammation and is defective in murine CGD. Blood (2013) 121: 3473–83. doi: 10. 1182/blood-2012-10-461913

||

82. Kohlgruber A, Lynch L. Adipose tissue inflammation in the pathogenesis of type 2 diabetes. Curr Diab Rep.(2015) 15: 429–11. doi: 10. 1007/s11892-015-0670-x

||

83. Zhang H, Xue R, Zhu S, Fu S, Chen Z, Zhou R, et al. M2-specific reduction of CD1d switches NKT cell-mediated immune responses and triggers metaflammation in adipose tissue. Cell Mol Immunol.(2017) 15: 506–17. doi: 10. 1038/cmi. 2017. 11

||

84. Satoh M, Iwabuchi K. Communication between natural killer T cells and adipocytes in obesity. Adipocyte (2016) 5: 389–93. doi: 10. 1080/21623945. 2016. 1241913

||

85. Ji Y, Sun S, Xu A, Bhargava P, Yang L, Lam KS, et al. Activation of natural killer T cells promotes M2 Macrophage polarization in adipose tissue and improves systemic glucose tolerance via interleukin-4 (IL-4)/STAT6 protein signaling axis in obesity. J Biol Chem.(2012) 287: 13561–71. doi: 10. 1074/jbc. M112. 350066

||

86. Schipper HS, Rakhshandehroo M, van de Graaf SF, Venken K, Koppen A, Stienstra R, et al. Natural killer T cells in adipose tissue prevent insulin resistance. J Clin Invest.(2012) 122: 3343–54. doi: 10. 1172/JCI62739

||

87. Wu L, Parekh VV, Gabriel CL, Bracy DP, Marks-Shulman PA, Tamboli RA, et al. Activation of invariant natural killer T cells by lipid excess promotes tissue inflammation, insulin resistance, and hepatic steatosis in obese mice. Proc Natl Acad Sci USA.(2012) 109: E1143–52. doi: 10. 1073/pnas. 1200498109

||

88. Felley L, Gumperz JE. Are human iNKT cells keeping tabs on lipidome perturbations triggered by oxidative stress in the blood? Immunogenetics (2016) 68: 611–22. doi: 10. 1007/s00251-016-0936-8

||

89. Eberl G, Colonna M, Di Santo JP, McKenzie AN. Innate lymphoid cells. Innate lymphoid cells: a new paradigm in immunology. Science (2015) 348: aaa6566. doi: 10. 1126/science. aaa6566

||

90. Moro K, Yamada T, Tanabe M, Takeuchi T, Ikawa T, Kawamoto H, et al. Innate production of T(H)2 cytokines by adipose tissue-associated c-Kit(+)Sca-1(+) lymphoid cells. Nature (2010) 463: 540–4. doi: 10. 1038/nature08636

||

91. Bénézech C, Luu NT, Walker JA, Kruglov AA, Loo Y, Nakamura K, et al. Inflammation-induced formation of fat-associated lymphoid clusters. Nat Immunol.(2015) 16: 819–28. doi: 10. 1038/ni. 3215

||

92. Saez de Guinoa J, Jimeno R, Gaya M, Kipling D, Garzón MJ, et al. CD1d-mediated lipid presentation by CD11c+ cells regulates intestinal homeostasis. EMBO J.(2018) 37: e97537. doi: 10. 15252/embj. 201797537

||

93. Murai M, Turovskaya O, Kim G, Madan R, Karp CL, Cheroutre H, et al. Interleukin 10 acts on regulatory T cells to maintain expression of the transcription factor Foxp3 and suppressive function in mice with colitis. Nat Immunol.(2009) 10: 1178–84. doi: 10. 1038/ni. 1791

||

94. Smith PD, Smythies LE, Shen R, Greenwell-Wild T, Gliozzi M, Wahl SM. Intestinal macrophages and response to microbial encroachment. Mucosal Immunol.(2010) 4: 31–42. doi: 10. 1038/mi. 2010. 66

||

95. Van Kaer L, Parekh VV, Wu L. The Response of CD1d-Restricted Invariant NKT Cells to Microbial Pathogens and Their Products. Front Immunol.(2015) 6: 226. doi: 10. 3389/fimmu. 2015. 00226

||

96. Brennan PJ, Brigl M, Brenner MB. Invariant natural killer T cells: an innate activation scheme linked to diverse effector functions. Nat Rev Immunol.(2013) 13: 101–17. doi: 10. 1038/nri3369

||

97. Tupin E, Kinjo Y, Kronenberg M. The unique role of natural killer T cells in the response to microorganisms. Nat Rev Microbiol.(2007) 5: 405–17. doi: 10. 1038/nrmicro1657

||

98. Wei B, Wingender G, Fujiwara D, Chen DY, McPherson M, Brewer S, et al. Commensal microbiota and CD8+ T cells shape the formation of invariant NKT cells. J Immunol.(2010) 184: 1218–26. doi: 10. 4049/jimmunol. 0902620

||

99. Wieland Brown LC, Penaranda C, Kashyap PC, Williams BB, Clardy J, Kronenberg M, et al. Production of α-galactosylceramide by a prominent member of the human gut microbiota. PloS Biol.(2013) 11: e1001610. doi: 10. 1371/journal. pbio. 1001610

||

100. Brennan PJ, Cheng TY, Pellicci DG, Watts GF, Veerapen N, Young DC, et al. Structural determination of lipid antigens captured at the CD1d–T-cell receptor interface. Proc Natl Acad Sci USA.(2017) 114: 8348–53. doi: 10. 1073/pnas. 1705882114

||

101. Fuss IJ, Heller F, Boirivant M, Leon F, Yoshida M, Fichtner-Feigl S, et al. Nonclassical CD1d-restricted NK T cells that produce IL-13 characterize an atypical Th2 response in ulcerative colitis. J Clin Invest.(2004) 113: 1490–7. doi: 10. 1172/JCI19836

||

102. Michel ML, Keller AC, Paget C, Fujio M, Trottein F, Savage PB, et al. Identification of an IL-17-producing NK1. 1(neg) iNKT cell population involved in airway neutrophilia. J Exp Med.(2007) 204: 995–1001. doi: 10. 1084/jem. 20061551

||

103. Shalapour S, Deiser K, Sercan Ö, Tuckermann J, Minnich K, Willimsky G, et al. Commensal microflora and interferon-γ promote steady-state interleukin-7 production in vivo . Eur J Immunol.(2010) 40: 2391–400. doi: 10. 1002/eji. 201040441

||

104. Webster KE, Kim HO, Kyparissoudis K, Corpuz TM, Pinget GV, Uldrich AP, et al. IL-17-producing NKT cells depend exclusively on IL-7 for homeostasis and survival. Mucosal Immunol.(2014) 7: 1058–67. doi: 10. 1038/mi. 2013. 122

||

105. Kim EY, Battaile JT, Patel AC, You Y, Agapov E, Grayson MH, et al. Persistent activation of an innate immune response translates respiratory viral infection into chronic lung disease. Nat Med.(2008) 14: 633–40. doi: 10. 1038/nm1770

||

106. Pichavant M, my GRE, Bekaert S, Le Rouzic O, Kervoaze G, Vilain E, et al. Oxidative stress-mediated iNKT-cell activation is involved in COPD pathogenesis. Mucosal Immunol.(2013) 7: 568–78. doi: 10. 1038/mi. 2013. 75

||

107. Mattner J, Debord KL, Ismail N, Goff RD, Cantu C, Zhou D, et al. Exogenous and endogenous glycolipid antigens activate NKT cells during microbial infections. Nature (2005) 434: 525–9. doi: 10. 1038/nature03408

||

108. Sada-Ovalle I, Chiba A, Gonzales A, Brenner MB, Behar SM. Innate invariant NKT cells recognize Mycobacterium tuberculosis-infected macrophages, produce interferon-gamma, and kill intracellular bacteria. PLoS Pathog.(2008) 4: e1000239. doi: 10. 1371/journal. ppat. 1000239

||

109. Nieuwenhuis EE, Matsumoto T, Exley M, Schleipman RA, Glickman J, Bailey DT, et al. CD1d-dependent macrophage-mediated clearance of Pseudomonas aeruginosa from lung. Nat Med.(2002) 8: 588–93. doi: 10. 1038/nm0602-588

||

110. Benoit P, Sigounas VY, Thompson JL, van Rooijen N, Poynter ME, Wargo MJ, et al. The role of CD1d-restricted NKT cells in the clearance of Pseudomonas aeruginosa from the lung is dependent on the host genetic background. Infect Immun.(2015) 83: 2557–65. doi: 10. 1128/IAI. 00015-15

||

111. Kinjo Y, Illarionov P, Vela JL, Pei B, Girardi E, Li X, et al. Invariant natural killer T cells recognize glycolipids from pathogenic Gram-positive bacteria. Nat Immunol.(2011) 12: 966–74. doi: 10. 1038/ni. 2096

||

112. Kok WL, Denney L, Benam K, Cole S, Clelland C, McMichael AJ, et al. Pivotal advance: invariant NKT cells reduce accumulation of inflammatory monocytes in the lungs and decrease immune-pathology during severe influenza A virus infection. J Leukoc Biol.(2012) 91: 357–68. doi: 10. 1189/jlb. 0411184

||

113. Paget C, Ivanov S, Fontaine J, Renneson J, Blanc F, Pichavant M, et al. Interleukin-22 is produced by invariant natural killer T lymphocytes during influenza A virus infection: potential role in protection against lung epithelial damages. J Biol Chem.(2012) 287: 8816–29. doi: 10. 1074/jbc. M111. 304758

||

114. Rothchild AC, Jayaraman P, Nunes-Alves C, Behar SM. iNKT cell production of GM-CSF controls Mycobacterium tuberculosis. PLoS Pathog.(2014) 10: e1003805. doi: 10. 1371/journal. ppat. 1003805

||

115. Noster R, Riedel R, Mashreghi MF, Radbruch H, Harms L, Haftmann C, et al. IL-17 and GM-CSF expression are antagonistically regulated by human T helper cells. Sci Transl Med.(2014) 6: 241ra80. doi: 10. 1126/scitranslmed. 3008706

||

116. Thanabalasuriar A, Neupane AS, Wang J, Krummel MF, Kubes P. iNKT cell emigration out of the lung vasculature requires neutrophils and monocyte-derived dendritic cells in inflammation. Cell Rep.(2016) 16: 3260–72. doi: 10. 1016/j. celrep. 2016. 07. 052

||

117. Ho LP, Denney L, Luhn K, Teoh D, Clelland C, McMichael AJ. Activation of invariant NKT cells enhances the innate immune response and improves the disease course in influenza A virus infection. Eur J Immunol.(2008) 38: 1913–22. doi: 10. 1002/eji. 200738017

||

118. Kamijuku H, Nagata Y, Jiang X, Ichinohe T, Tashiro T, Mori K, et al. Mechanism of NKT cell activation by intranasal coadministration of α-galactosylceramide, which can induce cross-protection against influenza viruses. Mucosal Immunol.(2008) 1: 208–18. doi: 10. 1038/mi. 2008. 2

||

119. Guillonneau C, Mintern JD, Hubert FX, Hurt AC, Besra GS, Porcelli S, et al. Combined NKT cell activation and influenza virus vaccination boosts memory CTL generation and protective immunity. Proc Natl Acad Sci USA.(2009) 106: 3330–5. doi: 10. 1073/pnas. 0813309106

||

120. Hanahan D, Coussens LM. Accessories to the crime: functions of cells recruited to the tumor microenvironment. Cancer Cell (2012) 21: 309–22. doi: 10. 1016/j. ccr. 2012. 02. 022

||

121. Klemm F, Joyce JA. Microenvironmental regulation of therapeutic response in cancer. Trends Cell Biol.(2015) 25: 198–213. doi: 10. 1016/j. tcb. 2014. 11. 006

||

122. Noy R, Pollard JW. Tumor-associated macrophages: from mechanisms to therapy. Immunity (2014) 41: 49–61. doi: 10. 1016/j. immuni. 2014. 06. 010

||

123. Metelitsa LS, Wu HW, Wang H, Yang Y, Warsi Z, Asgharzadeh S, et al. Natural killer T cells infiltrate neuroblastomas expressing the chemokine CCL2. J Exp Med.(2004) 199: 1213–21. doi: 10. 1084/jem. 20031462

||

124. Nowak M, Arredouani MS, Tun-Kyi A, Schmidt-Wolf I, Sanda MG, Balk SP, et al. Defective NKT cell activation by CD1d+ TRAMP prostate tumor cells is corrected by interleukin-12 with α-galactosylceramide. PLoS ONE (2010) 5: e11311. doi: 10. 1371/journal. pone. 0011311

||

125. Liu D, Song L, Wei J, Courtney AN, Gao X, Marinova E, et al. IL-15 protects NKT cells from inhibition by tumor-associated macrophages and enhances antimetastatic activity. J Clin Invest.(2012) 122: 2221–33. doi: 10. 1172/JCI59535

||

126. Ruffell B, Coussens LM. Macrophages and therapeutic resistance in cancer. Cancer Cell (2015) 27: 462–72. doi: 10. 1016/j. ccell. 2015. 02. 015

||

127. De Palma M, Biziato D, Petrova TV. Microenvironmental regulation of tumour angiogenesis. Nat Rev Cancer (2017) 17: 457–74. doi: 10. 1038/nrc. 2017. 51

||

128. Biswas SK, Mantovani A. Macrophage plasticity and interaction with lymphocyte subsets: cancer as a paradigm. Nat Immunol.(2010) 11: 889–96. doi: 10. 1038/ni. 1937

||

129. Song L, Asgharzadeh S, Salo J, Engell K, Wu HW, Sposto R, et al. Valpha24-invariant NKT cells mediate antitumor activity via killing of tumor-associated macrophages. J Clin Invest.(2009) 119: 1524–36. doi: 10. 1172/JCI37869

||

130. Janakiram NB, Mohammed A, Bryant T, Ritchie R, Stratton N, Jackson L, et al. Loss of natural killer T cells promotes pancreatic cancer in LSL-Kras G12D/+mice. Immunology (2017) 152: 36–51. doi: 10. 1111/imm. 12746

||

131. Tsukada N, Burger JA, Zvaifler NJ, Kipps TJ. Distinctive features of “ nurselike” cells that differentiate in the context of chronic lymphocytic leukemia. Blood (2002) 99: 1030–7. doi: 10. 1182/blood. V99. 3. 1030

||

132. Wang Y, Sedimbi S, Löfbom L, Singh AK, Porcelli SA, Cardell SL. Unique invariant natural killer T cells promote intestinal polyps by suppressing TH1 immunity and promoting regulatory T cells. Mucosal Immunol.(2018) 11: 131–43. doi: 10. 1038/mi. 2017. 34

||

133. Mars LT, Gautron AS, Novak J, Beaudoin L, Diana J, Liblau RS, et al. Invariant NKT cells regulate experimental autoimmune encephalomyelitis and infiltrate the central nervous system in a CD1d-independent manner. J Immunol.(2008) 181: 2321–9. doi: 10. 4049/jimmunol. 181. 4. 2321

||

134. Ascon DB, Ascon M, Satpute S, Lopez-Briones S, Racusen L, Colvin RB, et al. Normal mouse kidneys contain activated and CD3 +CD4 –CD8 –double-negative T lymphocytes with a distinct TCR repertoire. J Leukoc Biol.(2008) 84: 1400–9. doi: 10. 1189/jlb. 0907651

||

135. Riedel JH, Paust HJ, Turner JE, Tittel AP, Krebs C, Disteldorf E, et al. Immature renal dendritic cells recruit regulatory CXCR6(+) invariant natural killer T cells to attenuate crescentic GN. J Am Soc Nephrol.(2012) 23: 1987–2000. doi: 10. 1681/ASN. 2012040394

||

136. Watte CM, Nakamura T, Lau CH, Ortaldo JR, Stein-Streilein J. Ly49 C/I-dependent NKT cell-derived IL-10 is required for corneal graft survival and peripheral tolerance. J Leukoc Biol.(2008) 83: 928–35. doi: 10. 1189/jlb. 0807579

||

137. De Oliveira L, Larocca R, Sass N, Câmara NO. Proportion of invariant NKT cells in normal pregnant women at term: an evaluation in peripheral blood, placenta and umbilical cord blood. Am J Reprod Immunol.(2010) 65: 11–12. doi: 10. 1111/j. 1600-0897. 2010. 00915. x

||

138. Diana J, Griseri T, Lagaye S, Beaudoin L, Autrusseau E, Gautron AS, et al. NKT cell-plasmacytoid dendritic cell cooperation via OX40 controls viral infection in a tissue-specific manner. Immunity (2009) 30: 289–99. doi: 10. 1016/j. immuni. 2008. 12. 017

||

139. Yang SH, Lee JP, Jang HR, Cha RH, Han SS, Jeon US, et al. Sulfatide-reactive natural killer T cells abrogate ischemia-reperfusion injury. J Am Soc Nephrol.(2011) 22: 1305–14. doi: 10. 1681/ASN. 2010080815

||

140. Bajwa A, Huang L, Ye H, Dondeti K, Song S, Rosin DL, et al. Dendritic cell sphingosine 1-phosphate receptor-3 regulates Th1-Th2 polarity in kidney ischemia-reperfusion injury. J Immunol.(2012) 189: 2584–96. doi: 10. 4049/jimmunol. 1200999

||

141. Aguiar CF, Naffah-de-Souza C, Castoldi A, Corrêa-Costa M, Braga TT, Naka ÉL, et al. Administration of α-galactosylceramide improves adenine-induced renal injury. Mol Med.(2015) 21: 553–62. doi: 10. 2119/molmed. 2014. 00090

||

142. Lee S, Huen S, Nishio H, Nishio S, Lee HK, Choi BS, et al. Distinct macrophage phenotypes contribute to kidney injury and repair. J Am Soc Nephrol.(2011) 22: 317–26. doi: 10. 1681/ASN. 2009060615

||

143. Perez VL, Saeed AM, Tan Y, Urbieta M, Cruz-Guilloty F. The eye: a window to the soul of the immune system. J Autoimmun.(2013) 45: 7–14. doi: 10. 1016/j. jaut. 2013. 06. 011

||

144. Williams PJ, Searle RF, Robson SC, Innes BA, Bulmer JN. Decidual leucocyte populations in early to late gestation normal human pregnancy. J Reprod Immunol.(2009) 82: 24–31. doi: 10. 1016/j. jri. 2009. 08. 001

||

145. Habbeddine M, Verbeke P, Delarbre C, Moutier R, Prieto S, Ojcius DM, et al. CD1d-restricted NKT cells modulate placental and uterine leukocyte populations during chlamydial infection in mice. Microbes Infect.(2013) 15: 928–38. doi: 10. 1016/j. micinf. 2013. 08. 006

||

146. Svensson J, Jenmalm MC, Matussek A, Geffers R, Berg G, Ernerudh J. Macrophages at the fetal-maternal interface express markers of alternative activation and are induced by M-CSF and IL-10. J Immunol.(2011) 187: 3671–682. doi: 10. 4049/jimmunol. 1100130

||

147. Tard C, Rouxel O, Lehuen A. Regulatory role of natural killer T cells in diabetes. Biomed J.(2015) 38: 484–95. doi: 10. 1016/j. bj. 2015. 04. 001

||

148. Kim CH, Johnston B, Butcher EC. Trafficking machinery of NKT cells: shared and differential chemokine receptor expression among V alpha 24(+)V beta 11(+) NKT cell subsets with distinct cytokine-producing capacity. Blood (2002) 100: 11–16. doi: 10. 1182/blood-2001-12-0196

||

149. Johnston B, Kim CH, Soler D, Emoto M, Butcher EC. Differential chemokine responses and homing patterns of murine TCR alpha beta NKT cell subsets. J Immunol.(2003) 171: 2960–69. doi: 10. 4049/jimmunol. 171. 6. 2960

||

150. Thomas SY, Hou R, Boyson JE, Means TK, Hess C, Olson DP, et al. CD1d-restricted NKT cells express a chemokine receptor profile indicative of Th1-type inflammatory homing cells. J Immunol.(2003) 171: 2571–80. doi: 10. 4049/jimmunol. 171. 5. 2571

||

151. Slauenwhite D, Johnston B. Regulation of NKT cell localization in homeostasis and infection. Front Immunol.(2015) 6: 255. doi: 10. 3389/fimmu. 2015. 00255

||

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