RESUMEN
The contribution of γδ T cells to immune responses is associated with rapid secretion of interferon-γ (IFN-γ). Here, we show a perinatal thymic wave of innate IFN-γ-producing γδ T cells that express CD8αß heterodimers and expand in preclinical models of infection and cancer. Optimal CD8αß+ γδ T cell development is directed by low T cell receptor signaling and through provision of interleukin (IL)-4 and IL-7. This population is pathologically relevant as overactive, or constitutive, IL-7R-STAT5B signaling promotes a supraphysiological accumulation of CD8αß+ γδ T cells in the thymus and peripheral lymphoid organs in two mouse models of T cell neoplasia. Likewise, CD8αß+ γδ T cells define a distinct subset of human T cell acute lymphoblastic leukemia pediatric patients. This work characterizes the normal and malignant development of CD8αß+ γδ T cells that are enriched in early life and contribute to innate IFN-γ responses to infection and cancer.
Asunto(s)
Inmunidad Innata , Interferón gamma , Receptores de Antígenos de Linfocitos T gamma-delta , Receptores de Interleucina-7 , Factor de Transcripción STAT5 , Timo , Animales , Interferón gamma/metabolismo , Interferón gamma/inmunología , Ratones , Humanos , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Timo/inmunología , Receptores de Interleucina-7/metabolismo , Factor de Transcripción STAT5/metabolismo , Transducción de Señal/inmunología , Ratones Endogámicos C57BL , Linfocitos T CD8-positivos/inmunología , Ratones Noqueados , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Antígenos CD8/metabolismo , Femenino , Linfocitos Intraepiteliales/inmunología , Linfocitos Intraepiteliales/metabolismo , Interleucina-7/metabolismoRESUMEN
Metabolic programming controls immune cell lineages and functions, but little is known about γδ T cell metabolism. Here, we found that γδ T cell subsets making either interferon-γ (IFN-γ) or interleukin (IL)-17 have intrinsically distinct metabolic requirements. Whereas IFN-γ+ γδ T cells were almost exclusively dependent on glycolysis, IL-17+ γδ T cells strongly engaged oxidative metabolism, with increased mitochondrial mass and activity. These distinct metabolic signatures were surprisingly imprinted early during thymic development and were stably maintained in the periphery and within tumors. Moreover, pro-tumoral IL-17+ γδ T cells selectively showed high lipid uptake and intracellular lipid storage and were expanded in obesity and in tumors of obese mice. Conversely, glucose supplementation enhanced the antitumor functions of IFN-γ+ γδ T cells and reduced tumor growth upon adoptive transfer. These findings have important implications for the differentiation of effector γδ T cells and their manipulation in cancer immunotherapy.
Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias del Colon/metabolismo , Metabolismo Energético , Linfocitos Infiltrantes de Tumor/metabolismo , Melanoma Experimental/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Subgrupos de Linfocitos T/metabolismo , Timo/metabolismo , Microambiente Tumoral , Animales , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Línea Celular Tumoral , Linaje de la Célula , Neoplasias del Colon/inmunología , Neoplasias del Colon/patología , Neoplasias del Colon/terapia , Femenino , Glucosa/metabolismo , Glucólisis , Humanos , Inmunoterapia Adoptiva , Interferón gamma/metabolismo , Interleucina-17/metabolismo , Metabolismo de los Lípidos , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/trasplante , Melanoma Experimental/inmunología , Melanoma Experimental/patología , Melanoma Experimental/terapia , Ratones Endogámicos C57BL , Ratones Transgénicos , Mitocondrias/metabolismo , Obesidad/inmunología , Obesidad/metabolismo , Técnicas de Cultivo de Órganos , Fenotipo , Transducción de Señal , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/trasplante , Timo/inmunología , Carga TumoralRESUMEN
In mice, γδ-T lymphocytes that express the co-stimulatory molecule, CD27, are committed to the IFNγ-producing lineage during thymic development. In the periphery, these cells play a critical role in host defense and anti-tumor immunity. Unlike αß-T cells that rely on MHC-presented peptides to drive their terminal differentiation, it is unclear whether MHC-unrestricted γδ-T cells undergo further functional maturation after exiting the thymus. Here, we provide evidence of phenotypic and functional diversity within peripheral IFNγ-producing γδ T cells. We found that CD27+ Ly6C- cells convert into CD27+Ly6C+ cells, and these CD27+Ly6C+ cells control cancer progression in mice, while the CD27+Ly6C- cells cannot. The gene signatures of these two subsets were highly analogous to human immature and mature γδ-T cells, indicative of conservation across species. We show that IL-27 supports the cytotoxic phenotype and function of mouse CD27+Ly6C+ cells and human Vδ2+ cells, while IL-27 is dispensable for mouse CD27+Ly6C- cell and human Vδ1+ cell functions. These data reveal increased complexity within IFNγ-producing γδ-T cells, comprising immature and terminally differentiated subsets, that offer new insights into unconventional T-cell biology.
Asunto(s)
Antígenos Ly , Receptores de Antígenos de Linfocitos T gamma-delta , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral , Animales , Ratones , Antígenos Ly/metabolismo , Antígenos Ly/genética , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismo , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/genética , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/inmunología , Humanos , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Interferón gamma/metabolismo , Interferón gamma/inmunología , Interleucina-27/metabolismo , Interleucina-27/genética , Diferenciación Celular/inmunología , Ratones Endogámicos C57BL , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/metabolismoRESUMEN
The mouse thymus produces discrete γδ T cell subsets that make either interferon-γ (IFN-γ) or interleukin 17 (IL-17), but the role of the T cell antigen receptor (TCR) in this developmental process remains controversial. Here we show that Cd3g(+/-) Cd3d(+/-) (CD3 double-haploinsufficient (CD3DH)) mice have reduced TCR expression and signaling strength on γδ T cells. CD3DH mice had normal numbers and phenotypes of αß thymocyte subsets, but impaired differentiation of fetal Vγ6(+) (but not Vγ4(+)) IL-17-producing γδ T cells and a marked depletion of IFN-γ-producing CD122(+) NK1.1(+) γδ T cells throughout ontogeny. Adult CD3DH mice showed reduced peripheral IFN-γ(+) γδ T cells and were resistant to experimental cerebral malaria. Thus, TCR signal strength within specific thymic developmental windows is a major determinant of the generation of proinflammatory γδ T cell subsets and their impact on pathophysiology.
Asunto(s)
Diferenciación Celular , Inflamación/inmunología , Malaria Cerebral/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Subgrupos de Linfocitos T/fisiología , Linfocitos T/fisiología , Timo/inmunología , Animales , Antígenos Ly/metabolismo , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Interferón gamma/metabolismo , Interleucina-17/metabolismo , Subunidad beta del Receptor de Interleucina-2/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Subfamilia B de Receptores Similares a Lectina de Células NK/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Transducción de SeñalRESUMEN
Two distinct subsets of γδ T cells that produce interleukin 17 (IL-17) (CD27(-) γδ T cells) or interferon-γ (IFN-γ) (CD27(+) γδ T cells) develop in the mouse thymus, but the molecular determinants of their functional potential in the periphery remain unknown. Here we conducted a genome-wide characterization of the methylation patterns of histone H3, along with analysis of mRNA encoding transcription factors, to identify the regulatory networks of peripheral IFN-γ-producing or IL-17-producing γδ T cell subsets in vivo. We found that CD27(+) γδ T cells were committed to the expression of Ifng but not Il17, whereas CD27(-) γδ T cells displayed permissive chromatin configurations at loci encoding both cytokines and their regulatory transcription factors and differentiated into cells that produced both IL-17 and IFN-γ in a tumor microenvironment.
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Diferenciación Celular/genética , Epigénesis Genética , Perfilación de la Expresión Génica , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/metabolismo , Transcriptoma , Animales , Citocinas/genética , Citocinas/metabolismo , Femenino , Regulación de la Expresión Génica , Estudio de Asociación del Genoma Completo , Histonas/metabolismo , Metilación , Ratones , Ratones Noqueados , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Subgrupos de Linfocitos T/inmunología , Células TH1/inmunología , Células TH1/metabolismo , Células Th17/inmunología , Células Th17/metabolismoRESUMEN
The production of cytokines such as interferon-gamma and interleukin 17 by alphabeta and gammadelta T cells influences the outcome of immune responses. Here we show that most gammadelta T lymphocytes expressed the tumor necrosis factor receptor family member CD27 and secreted interferon-gamma, whereas interleukin 17 production was restricted to CD27(-) gammadelta T cells. In contrast to the apparent plasticity of alphabeta T cells, the cytokine profiles of these distinct gammadelta T cell subsets were essentially stable, even during infection. These phenotypes were established during thymic development, when CD27 functions as a regulator of the differentiation of gammadelta T cells at least in part by inducing expression of the lymphotoxin-beta receptor and genes associated with trans-conditioning and interferon-gamma production. Thus, the cytokine profiles of peripheral gammadelta T cells are predetermined mainly by a mechanism involving CD27.
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Interferón gamma/inmunología , Interleucina-17/inmunología , Células Progenitoras Linfoides/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Subgrupos de Linfocitos T/inmunología , Timo/inmunología , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/inmunología , Animales , Ligando CD27/inmunología , Células Cultivadas , Receptor beta de Linfotoxina/inmunología , Malaria Cerebral/inmunología , Ratones , Ratones Endogámicos C57BL , Plasmodium berghei , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/genéticaRESUMEN
γd T cells have emerged as major sources of the proinflammatory cytokines interleukin-17 (IL-17) and interferon-γ (IFNγ) in multiple models of infection, cancer and autoimmune disease. However, unlike their αß T cell counterparts that require peripheral activation for effector cell differentiation, γδ T cells instead can be 'developmentally programmed' in the thymus to generate discrete γδ T cell effector subsets with distinctive molecular signatures. Nonetheless, recent studies have presented conflicting viewpoints on the signals involved in thymic γδ T cell development and differentiation, namely on the role of both T cell receptor (TCR)-dependent and TCR-independent factors. Here we review the current data and the ongoing controversies.
Asunto(s)
Diferenciación Celular/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Subgrupos de Linfocitos T/inmunología , Timo/inmunología , Animales , Citocinas/inmunología , Citocinas/metabolismo , Humanos , Activación de Linfocitos/inmunología , Modelos Inmunológicos , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Transducción de Señal/inmunología , Subgrupos de Linfocitos T/metabolismo , Timo/metabolismoRESUMEN
Murine γδ T cells display diverse responses to pathogens and tumours through early provision of pro-inflammatory cytokines such as interleukin-17A (IL-17) and interferon-γ (IFN-γ). Although it is now clear that acquisition of these cytokine-secreting effector fates is to a great extent developmentally pre-programmed in the thymus, the stages through which γδ progenitor cells transition, and the underlying mechanistic processes that govern these commitment events, are still largely unclear. Here, we review recent progress in the field, with particular consideration of how TCR-γδ signalling impacts on developmental programmes initiated before TCR-γδ expression.
Asunto(s)
Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Subgrupos de Linfocitos T/inmunología , Animales , Ratones , Transducción de Señal/inmunologíaRESUMEN
Human γδ T cells display potent responses to pathogens and malignancies. Of particular interest are those expressing a γδ T-cell receptor (TCR) incorporating TCRδ-chain variable-region-2 [Vδ2(+)], which are activated by pathogen-derived phosphoantigens (pAgs), or host-derived pAgs that accumulate in transformed cells or in cells exposed to aminobisphosphonates. Once activated, Vδ2(+) T cells exhibit multiple effector functions that have made them attractive candidates for immunotherapy. Despite this, clinical trials have reported mixed patient responses, highlighting a need for better understanding of Vδ2(+) T-cell biology. Here, we reveal previously unappreciated functional heterogeneity between the Vδ2(+) T-cell compartments of 63 healthy individuals. In this cohort, we identify distinct "Vδ2 profiles" that are stable over time; that do not correlate with age, gender, or history of phosphoantigen activation; and that develop after leaving the thymus. Multiple analyses suggest these Vδ2 profiles consist of variable proportions of two dominant but contrasting Vδ2(+) T-cell subsets that have divergent transcriptional programs and that display mechanistically distinct cytotoxic potentials. Importantly, an individual's Vδ2 profile predicts defined effector capacities, demonstrated by contrasting mechanisms and efficiencies of killing of a range of tumor cell lines. In short, these data support patient stratification to identify individuals with Vδ2 profiles that have effector mechanisms compatible with tumor killing and suggest that tailored Vδ2-profile-specific activation protocols may maximize the chances of future treatment success.
Asunto(s)
Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Subgrupos de Linfocitos T/inmunología , Linfocitos T Citotóxicos/inmunología , Adolescente , Adulto , Anciano , Receptor 1 de Quimiocinas CX3C/metabolismo , Niño , Preescolar , Citotoxicidad Inmunológica , Femenino , Perfilación de la Expresión Génica , Genes Codificadores de la Cadena delta de los Receptores de Linfocito T , Voluntarios Sanos , Humanos , Inmunofenotipificación , Activación de Linfocitos/inmunología , Masculino , Persona de Mediana Edad , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Receptores CCR6/metabolismo , Adulto JovenRESUMEN
[This corrects the article DOI: 10.1371/journal.pmed.1002352.].
RESUMEN
BACKGROUND: Severe trauma induces a widespread response of the immune system. This "genomic storm" can lead to poor outcomes, including Multiple Organ Dysfunction Syndrome (MODS). MODS carries a high mortality and morbidity rate and adversely affects long-term health outcomes. Contemporary management of MODS is entirely supportive, and no specific therapeutics have been shown to be effective in reducing incidence or severity. The pathogenesis of MODS remains unclear, and several models are proposed, such as excessive inflammation, a second-hit insult, or an imbalance between pro- and anti-inflammatory pathways. We postulated that the hyperacute window after trauma may hold the key to understanding how the genomic storm is initiated and may lead to a new understanding of the pathogenesis of MODS. METHODS AND FINDINGS: We performed whole blood transcriptome and flow cytometry analyses on a total of 70 critically injured patients (Injury Severity Score [ISS] ≥ 25) at The Royal London Hospital in the hyperacute time period within 2 hours of injury. We compared transcriptome findings in 36 critically injured patients with those of 6 patients with minor injuries (ISS ≤ 4). We then performed flow cytometry analyses in 34 critically injured patients and compared findings with those of 9 healthy volunteers. Immediately after injury, only 1,239 gene transcripts (4%) were differentially expressed in critically injured patients. By 24 hours after injury, 6,294 transcripts (21%) were differentially expressed compared to the hyperacute window. Only 202 (16%) genes differentially expressed in the hyperacute window were still expressed in the same direction at 24 hours postinjury. Pathway analysis showed principally up-regulation of pattern recognition and innate inflammatory pathways, with down-regulation of adaptive responses. Immune deconvolution, flow cytometry, and modular analysis suggested a central role for neutrophils and Natural Killer (NK) cells, with underexpression of T- and B cell responses. In the transcriptome cohort, 20 critically injured patients later developed MODS. Compared with the 16 patients who did not develop MODS (NoMODS), maximal differential expression was seen within the hyperacute window. In MODS versus NoMODS, 363 genes were differentially expressed on admission, compared to only 33 at 24 hours postinjury. MODS transcripts differentially expressed in the hyperacute window showed enrichment among diseases and biological functions associated with cell survival and organismal death rather than inflammatory pathways. There was differential up-regulation of NK cell signalling pathways and markers in patients who would later develop MODS, with down-regulation of neutrophil deconvolution markers. This study is limited by its sample size, precluding more detailed analyses of drivers of the hyperacute response and different MODS phenotypes, and requires validation in other critically injured cohorts. CONCLUSIONS: In this study, we showed how the hyperacute postinjury time window contained a focused, specific signature of the response to critical injury that led to widespread genomic activation. A transcriptomic signature for later development of MODS was present in this hyperacute window; it showed a strong signal for cell death and survival pathways and implicated NK cells and neutrophil populations in this differential response.
Asunto(s)
Inflamación/inmunología , Insuficiencia Multiorgánica/diagnóstico , Insuficiencia Multiorgánica/etiología , Insuficiencia Multiorgánica/terapia , Heridas y Lesiones/complicaciones , Heridas y Lesiones/terapia , Enfermedad Aguda , Adulto , Análisis Químico de la Sangre , Femenino , Citometría de Flujo , Humanos , Inflamación/sangre , Inflamación/etiología , Inflamación/terapia , Londres , Masculino , Persona de Mediana Edad , Insuficiencia Multiorgánica/inmunología , Estudios Prospectivos , Factores de Tiempo , Transcriptoma , Heridas y Lesiones/sangre , Heridas y Lesiones/inmunologíaRESUMEN
Cancer-associated inflammation mobilizes a variety of leukocyte populations that can inhibit or enhance tumor cell growth in situ. These subsets include γδ T cells, which can infiltrate tumors and typically provide large amounts of antitumor cytokines, such as IFN-γ. By contrast, we report here that in a well-established transplantable (ID8 cell line) model of peritoneal/ovarian cancer, γδ T cells promote tumor cell growth. γδ T cells accumulated in the peritoneal cavity in response to tumor challenge and could be visualized within solid tumor foci. Functional characterization of tumor-associated γδ T cells revealed preferential production of interleukin-17A (IL-17), rather than IFN-γ. Consistent with this finding, both T cell receptor (TCR)δ-deficient and IL-17-deficient mice displayed reduced ID8 tumor growth compared with wild-type animals. IL-17 production by γδ T cells in the tumor environment was essentially restricted to a highly proliferative CD27((-)) subset that expressed Vγ6 instead of the more common Vγ1 and Vγ4 TCR chains. The preferential expansion of IL-17-secreting CD27((-)) Vγ6((+)) γδ T cells associated with the selective mobilization of unconventional small peritoneal macrophages (SPMs) that, in comparison with large peritoneal macrophages, were enriched for IL-17 receptor A, and for protumor and proangiogenic molecular mediators, which were up-regulated by IL-17. Importantly, SPMs were uniquely and directly capable of promoting ovarian cancer cell proliferation. Collectively, this work identifies an IL-17-dependent lymphoid/myeloid cross-talk involving γδ T cells and SPMs that promotes tumor cell growth and thus counteracts cancer immunosurveillance.
Asunto(s)
Interleucina-17/biosíntesis , Macrófagos Peritoneales/inmunología , Neoplasias Ováricas/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Subgrupos de Linfocitos T/inmunología , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Femenino , Mediadores de Inflamación/metabolismo , Linfocitos Infiltrantes de Tumor/clasificación , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/patología , Macrófagos Peritoneales/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neovascularización Patológica , Neoplasias Ováricas/patología , Receptores de Antígenos de Linfocitos T gamma-delta/deficiencia , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Receptores de Interleucina-17/metabolismo , Subgrupos de Linfocitos T/patología , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/deficiencia , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/genéticaRESUMEN
Inflammation occurs as a result of exposure of tissues and organs to harmful stimuli such as microbial pathogens, irritants, or toxic cellular components. The primary physical manifestations of inflammation are redness, swelling, heat, pain, and loss of function to the affected area. These processes involve the major cells of the immune system, including monocytes, macrophages, neutrophils, basophils, dendritic cells, mast cells, T-cells, and B-cells. However, examination of a range of inflammatory lesions demonstrates the presence of specific leukocytes in any given lesion. That is, the inflammatory process is regulated in such a way as to ensure that the appropriate leukocytes are recruited. These events are in turn controlled by a host of extracellular molecular regulators, including members of the cytokine and chemokine families that mediate both immune cell recruitment and complex intracellular signalling control mechanisms that characterise inflammation. This review will focus on the role of the main cytokines, chemokines, and their receptors in the pathophysiology of auto-inflammatory disorders, pro-inflammatory disorders, and neurological disorders involving inflammation.
RESUMEN
IL-17-producing CD27(-) γδ cells (γδ(27-) cells) are widely viewed as innate immune cells that make critical contributions to host protection and autoimmunity. However, factors that promote them over IFN-γ-producing γδ(27+) cells are poorly elucidated. Moreover, although human IL-17-producing γδ cells are commonly implicated in inflammation, such cells themselves have proved difficult to isolate and characterize. Here, murine γδ(27-) T cells and thymocytes are shown to be rapidly and substantially expanded by IL-7 in vitro and in vivo. This selectivity owes in substantial part to the capacity of IL-7 to activate STAT3 in such cells. Additionally, IL-7 promotes strong responses of IL-17-producing γδ cells to TCR agonists, thus reemphasizing the cells' adaptive and innate potentials. Moreover, human IL-17-producing γδ cells are also substantially expanded by IL-7 plus TCR agonists. Hence, IL-7 has a conserved potential to preferentially regulate IL-17-producing γδ cells, with both biological and clinical implications.
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Interleucina-17/biosíntesis , Interleucina-7/fisiología , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Linfocitos T/metabolismo , Animales , Células Cultivadas , Humanos , RatonesRESUMEN
The thymus generates T cells that are generally functionally immature and thus require peripheral activation for differentiation into effector lymphocytes. Notable exceptions to this rule are murine γδ T cells, many of which have been shown to acquire their functional potential during thymic development from late embryonic stages. Here, we review the underlying ontogenic processes and molecular differentiation mechanisms of murine γδ T cells, focusing on the transcriptional control of IFN-γ and IL-17 expression. We propose that functional commitment of γδ T cells occurs in "developmental windows" defined by the molecular composition of the thymic microenvironment, such as T-cell receptor (TCR), TCR coreceptor ligands, and cytokines. We further discuss the similarities and particularities of functional development of γδ T cells in mice and humans, while highlighting some key unresolved issues for future investigation.
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Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/análisis , Subgrupos de Linfocitos T/inmunología , Timo/embriología , Animales , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Diferenciación Celular , Linaje de la Célula , Humanos , Interferón gamma/biosíntesis , Interleucina-17/biosíntesis , Ratones , Subgrupos de Linfocitos T/metabolismo , Timo/metabolismo , Transcripción GenéticaRESUMEN
γδ cells have been conserved across â¼450 million years of evolution, from which they share the distinction, alongside αß T cells and B cells, of forming antigen receptors by somatic gene recombination. However, much about these cells remains unclear. Indeed, although γδ cells display 'innate-like' characteristics exemplified by rapid tissue-localised responses to stress-associated stimuli, their huge capacity for T cell receptor (TCR)γδ diversity also suggests 'adaptive-like' potential. Clarity requires a better understanding of TCRγδ itself, not only through identification of TCR ligands, but also by correlating thymic TCRγδ signalling with commitment to γδ effector fates. Here, we propose that thymic TCRγδ-ligand engagement versus ligand-independent signalling differentially imprints innate-like versus adaptive-like characteristics on developing γδ cells, which fundamentally dictate their peripheral effector properties.
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Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Transducción de Señal , Linfocitos T/inmunología , Inmunidad Adaptativa , Animales , Linaje de la Célula , Humanos , Inmunidad Innata , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Linfocitos T/citología , Linfocitos T/metabolismoRESUMEN
Immunotherapies for cancers of epithelial origin have limited efficacy, and a growing body of evidence links the composition of extracellular matrix (ECM) with the likelihood of a favorable response to treatment. The ECM may be considered an immunologic barrier, restricting the localization of cytotoxic immune cells to stromal areas and inhibiting their contact with tumor cells. Identifying ECM components of this immunologic barrier could provide targets that whether degraded in situ may support antitumor immunity and improve immunotherapy response. Using a library of primary triple-negative breast cancer tissues, we correlated CD8+ T-cell tumor contact with ECM composition and identified a proteoglycan, versican (VCAN), as a putative member of the immunologic barrier. Our analysis reveals that CD8+ T-cell contact with tumor associates with the location of VCAN expression, the specific glycovariant of VCAN [defined through the pattern of posttranslational attachments of glycosaminoglycans (GAG)], and the cell types that produce the variant. In functional studies, the isomers of chondroitin sulfate presented on VCAN have opposing roles being either supportive or inhibiting of T-cell trafficking, and removal of the GAGs ameliorates these effects on T-cell trafficking. Overall, we conclude that VCAN can either support or inhibit T-cell trafficking within the tumor microenvironment depending on the pattern of GAGs present, and that VCAN is a major component of the ECM immunologic barrier that defines the type of response to immunotherapy. SIGNIFICANCE: The response to immunotherapy has been poor toward solid tumors despite immune cells infiltrating into the tumor. The ECM has been associated with impacting T-cell infiltration toward the tumor and in this article we have identified VCAN and its structural modification, chondroitin sulfate as having a key role in T-cell invasion.
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Neoplasias , Versicanos , Humanos , Linfocitos T CD8-positivos/metabolismo , Sulfatos de Condroitina , Fenotipo , Microambiente Tumoral , Versicanos/química , AnimalesRESUMEN
Background and Aims: Survival rates for esophageal squamous cell carcinoma (ESCC) are extremely low due to the late diagnosis of most cases. An understanding of the early molecular processes that lead to ESCC may facilitate opportunities for early diagnosis; however, these remain poorly defined. Tylosis with esophageal cancer (TOC) is a rare syndrome associated with a high lifetime risk of ESCC and germline mutations in RHBDF2, encoding iRhom2. Using TOC as a model of ESCC predisposition, this study aimed to identify early-stage transcriptional changes in ESCC development. Methods: Esophageal biopsies were obtained from control and TOC individuals, the latter undergoing surveillance endoscopy, and adjacent diagnostic biopsies were graded as having no dysplasia or malignancy. Bulk RNA-Seq was performed, and findings were compared with sporadic ESCC vs normal RNA-Seq datasets. Results: Multiple transcriptional changes were identified in TOC samples, relative to controls, and many were detected in ESCC. Accordingly, pathway analyses predicted an enrichment of cancer-associated processes linked to cellular proliferation and metastasis, and several transcription factors were predicted to be associated with TOC and ESCC, including negative enrichment of GRHL2. Subsequently, a filtering strategy revealed 22 genes that were significantly dysregulated in both TOC and ESCC. Moreover, Keratin 17, which was upregulated in TOC and ESCC, was also found to be overexpressed at the protein level in 'normal' TOC esophagus tissue. Conclusion: Transcriptional changes occur in TOC esophagus prior to the onset of dysplasia, many of which are associated with ESCC. These findings support the utility of TOC to help reveal the early molecular processes that lead to sporadic ESCC.
RESUMEN
Under non-pathological conditions, human γδ T cells represent a small fraction of CD3+ T cells in peripheral blood (1-10%). They constitute a unique subset of T lymphocytes that recognize stress ligands or non-peptide antigens through MHC-independent presentation. Major human γδ T cell subsets, Vδ1 and Vδ2, expand in response to microbial infection or malignancy, but possess distinct tissue localization, antigen recognition, and effector responses. We hypothesized that differences at the gene, phenotypic, and functional level would provide evidence that γδ T cell subpopulations belong to distinct lineages. Comparisons between each subset and the identification of the molecular determinants that underpin their differences has been hampered by experimental challenges in obtaining sufficient numbers of purified cells. By utilizing a stringent FACS-based isolation method, we compared highly purified human Vδ1 and Vδ2 cells in terms of phenotype, gene expression profile, and functional responses. We found distinct genetic and phenotypic signatures that define functional differences in γδ T cell populations. Differences in TCR components, repertoire, and responses to calcium-dependent pathways suggest that Vδ1 and Vδ2 T cells are different lineages. These findings will facilitate further investigation into the ligand specificity and unique role of Vδ1 and Vδ2 cells in early immune responses.
Asunto(s)
Linfocitos Intraepiteliales , Neoplasias , Humanos , Subgrupos de Linfocitos T , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Linfocitos Intraepiteliales/metabolismo , Fenotipo , Neoplasias/metabolismoRESUMEN
γδ T cells are increasingly recognized as having important functional roles in a range of disease scenarios such as infection, allergy, autoimmunity and cancer. With this has come realization that γδ cells are not a homogeneous population of cells with a single physiological role. Instead, ever increasing complexity in both phenotype and function is being ascribed to γδ cell subsets from various tissues and locations, and in both mouse and human. Here, we review this complexity by describing how diverse γδ cell subsets are generated in the murine thymus, and how these events relate to subsequent γδ subset function in the periphery. We then review the two major γδ cell populations in human, highlighting the several similarities of Vδ1(+) cells to certain murine γδ subsets, and describing the remarkable functional plasticity of human Vδ2(+) cells. A better understanding of this spectrum of γδ cell phenotypes should facilitate more targeted approaches to utilise their tremendous functional potential in the clinic.