RESUMEN
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.
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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.
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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 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.
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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
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
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.
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Linfocitos Intraepiteliales , Neoplasias , Humanos , Subgrupos de Linfocitos T , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Linfocitos Intraepiteliales/metabolismo , Fenotipo , Neoplasias/metabolismoRESUMEN
The assessment of the cellular heterogeneity and abundance in bulk tissue samples is essential for characterising cellular and organismal states. Computational approaches to estimate cellular abundance from bulk RNA-Seq datasets have variable performances, often requiring benchmarking matrices to select the best performing methods for individual studies. However, such benchmarking investigations are difficult to perform and assess in typical applications because of the absence of gold standard/ground-truth cellular measurements. Here we describe Decosus, an R package that integrates seven methods and signatures for deconvoluting cell types from gene expression profiles (GEP). Benchmark analysis on a range of datasets with ground-truth measurements revealed that our integrated estimates consistently exhibited stable performances across datasets than individual methods and signatures. We further applied Decosus to characterise the immune compartment of skin samples in different settings, confirming the well-established Th1 and Th2 polarisation in psoriasis and atopic dermatitis, respectively. Secondly, we revealed immune system-related UV-induced changes in sun-exposed skin. Furthermore, a significant motivation in the design of Decosus is flexibility and the ability for the user to include new gene signatures, algorithms, and integration methods at run time.
RESUMEN
Murine γδ17 cells, which are T cells that bear the γδ T cell receptor (TCRγδ) and secrete interleukin-17A (IL-17A), are generated in the thymus and are critical for various immune responses. Although strong TCRγδ signals are required for the development of interferon-γ (IFN-γ)-secreting γδ cells (γδIFN cells), the generation of γδ17 cells requires weaker TCRγδ signaling. Here, we demonstrated that constrained activation of the kinase Syk downstream of TCRγδ was required for the thymic development of γδ17 cells. Increasing or decreasing Syk activity by stimulating TCRγδ or inhibiting Syk, respectively, substantially reduced γδ17 cell numbers. This delimited Syk activity optimally engaged the phosphoinositide 3-kinase (PI3K)-Akt signaling pathway, which maintained the expression of master regulators of the IL-17 program, RORγt and c-Maf. Inhibition of PI3K not only abrogated γδ17 cell development but also augmented the development of a distinct, previously undescribed subset of γδ T cells. These CD8+Ly6a+ γδ T cells had a type-I IFN gene expression signature and expanded in response to stimulation with IFN-ß. Collectively, these studies elucidate how weaker TCRγδ signaling engages distinct signaling pathways to specify the γδ17 cell fate and identifies a role for type-I IFNs in γδ T cell development.
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Interleucina-17 , Receptores de Antígenos de Linfocitos T gamma-delta , Animales , Interleucina-17/genética , Ratones , Ratones Endogámicos C57BL , Fosfatidilinositol 3-Quinasa , Fosfatidilinositol 3-Quinasas/genética , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Linfocitos TRESUMEN
BACKGROUND AND AIMS: Aging is the primary risk factor for cardiovascular disease (CVD), but the mechanisms underlying age-linked atherosclerosis remain unclear. We previously observed that long-lived vascular matrix proteins can acquire 'gain-of-function' isoDGR motifs that might play a role in atherosclerotic pathology. METHODS: IsoDGR-specific mAb were generated and used for ELISA-based measurement of motif levels in plasma samples from patients with coronary artery diseases (CAD) and non-CAD controls. Functional consequences of isoDGR accumulation in age-damaged fibronectin were determined by bioassay for capacity to activate monocytes, macrophages, and endothelial cells (signalling activity, pro-inflammatory cytokine expression, and recruitment/adhesion potential). Mice deficient in the isoDGR repair enzyme PCMT1 were used to assess motif distribution and macrophage localisation in vivo. RESULTS: IsoDGR-modified fibronectin and fibrinogen levels in patient plasma were significantly enhanced in CAD and further associated with smoking status. Functional assays demonstrated that isoDGR-modified fibronectin activated both monocytes and macrophages via integrin receptor 'outside in' signalling, triggering an ERK:AP-1 cascade and expression of pro-inflammatory cytokines MCP-1 and TNFα to drive additional recruitment of circulating leukocytes. IsoDGR-modified fibronectin also induced endothelial cell expression of integrin ß1 to further enhance cellular adhesion and matrix deposition. Analysis of murine aortic tissues confirmed accumulation of isoDGR-modified proteins co-localised with CD68+ macrophages in vivo. CONCLUSIONS: Age-damaged fibronectin features isoDGR motifs that increase binding to integrins on the surface of monocytes, macrophages, and endothelial cells. Subsequent activation of 'outside-in' signalling elicits a range of potent cytokines and chemokines that drive additional leukocyte recruitment to the developing atherosclerotic matrix.
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Aterosclerosis , Monocitos , Envejecimiento , Animales , Adhesión Celular , Células Endoteliales , Fibronectinas , Humanos , Ratones , Proteína D-Aspartato-L-Isoaspartato MetiltransferasaRESUMEN
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.
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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
The palmoplantar epidermis is a specialized area of the skin that undergoes high levels of mechanical stress. The palmoplantar keratinization and esophageal cancer syndrome, tylosis with esophageal cancer, is linked to mutations in RHBDF2 encoding the proteolytically inactive rhomboid protein, iRhom2. Subsequently, iRhom2 was found to affect palmoplantar thickening to modulate the stress keratin response and to mediate context-dependent stress pathways by p63. iRhom2 is also a direct regulator of the sheddase, ADAM17, and the antiviral adaptor protein, stimulator of IFN genes. In this perspective, the pleiotropic functions of iRhom2 are discussed with respect to the skin, inflammation, and the antiviral response.
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Dermatitis/inmunología , Epidermis/patología , Neoplasias Esofágicas/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Queratodermia Palmoplantar/genética , Enfermedades Cutáneas Virales/inmunología , Proteína ADAM17/metabolismo , Animales , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Dermatitis/genética , Modelos Animales de Enfermedad , Epidermis/inmunología , Neoplasias Esofágicas/inmunología , Neoplasias Esofágicas/patología , Pie , Regulación de la Expresión Génica/inmunología , Mano , Interacciones Microbiota-Huesped/genética , Interacciones Microbiota-Huesped/inmunología , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Queratinocitos/inmunología , Queratinocitos/metabolismo , Queratinas/metabolismo , Queratodermia Palmoplantar/inmunología , Queratodermia Palmoplantar/patología , Ratones , Ratones Noqueados , Mutación , Transducción de Señal/genética , Transducción de Señal/inmunología , Enfermedades Cutáneas Virales/genética , Enfermedades Cutáneas Virales/virología , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismoRESUMEN
Crosstalk between innate and adaptive pathways is a critical component to developing an effective, lasting immune response. Among natural effector cells, innate-like γδ T cells promote immunity by facilitating communication between the two compartments and exerting cytotoxic effector functions. Dysregulation of γδ T cell populations is a byproduct of primary Humanimmunodeficiency virus (HIV) infection. This is most pronounced in the depletion and loss of function within cells expressing a Vγ9Vδ2 TCR (Vδ2 cells). Whether or not prolonged viral suppression mediated by antiretroviral therapy (ART) can reverse these effects has yet to be determined. In this study, we present evidence of similar Vδ2 cell functional responses within a cohort of people living with HIV (PLWH) that has been stably suppressed for >1 year and uninfected donors. Through the use of aminobisphosphonate drugs, we were able to generate a comprehensive comparison between ex vivo and expanded Vδ2 cells within each group. Both groups had largely similar compositions of memory and effector phenotypes, post-expansion TCR repertoire diversity, and cytotoxic capabilities. Our findings support the notion that ART promotes the recovery of Vδ2 polyfunctionality and provides insight for strategies aiming to reconstitute the full immune response after infection with HIV.
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Infecciones por VIH/inmunología , VIH/inmunología , Linfocitos Intraepiteliales/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/inmunología , Adulto , Antirretrovirales/uso terapéutico , Línea Celular Tumoral , Femenino , VIH/efectos de los fármacos , Infecciones por VIH/tratamiento farmacológico , Humanos , Memoria Inmunológica/inmunología , Masculino , FenotipoRESUMEN
Deep sequencing of B cell receptor (BCR) heavy chains from a cohort of 31 COVID-19 patients from the UK reveals a stereotypical naive immune response to SARS-CoV-2 which is consistent across patients. Clonal expansion of the B cell population is also observed and may be the result of memory bystander effects. There was a strong convergent sequence signature across patients, and we identified 1,254 clonotypes convergent between at least four of the COVID-19 patients, but not present in healthy controls or individuals following seasonal influenza vaccination. A subset of the convergent clonotypes were homologous to known SARS and SARS-CoV-2 spike protein neutralizing antibodies. Convergence was also demonstrated across wide geographies by comparison of data sets between patients from UK, USA, and China, further validating the disease association and consistency of the stereotypical immune response even at the sequence level. These convergent clonotypes provide a resource to identify potential therapeutic and prophylactic antibodies and demonstrate the potential of BCR profiling as a tool to help understand patient responses.
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Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/patología , Receptores de Antígenos de Linfocitos B/genética , SARS-CoV-2/inmunología , Linfocitos B/inmunología , COVID-19/inmunología , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Linfopenia/inmunología , Masculino , Persona de Mediana Edad , Glicoproteína de la Espiga del Coronavirus/inmunologíaAsunto(s)
Receptores de Antígenos de Linfocitos T gamma-delta/fisiología , Subgrupos de Linfocitos T/inmunología , Animales , Butirofilinas/fisiología , Congresos como Asunto , Humanos , Inmunoterapia , Infecciones/inmunología , Inflamación/inmunología , Activación de Linfocitos , Neoplasias/inmunología , Receptores Mensajeros de Linfocitos/fisiología , Subgrupos de Linfocitos T/fisiologíaRESUMEN
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.
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Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Subgrupos de Linfocitos T/inmunología , Animales , Ratones , Transducción de Señal/inmunologíaRESUMEN
[This corrects the article DOI: 10.1371/journal.pmed.1002352.].
RESUMEN
CD4(+)CD8(+) "double positive" (DP) thymocytes differentiate into diverse αß T cell sub-types using mechanistically distinct programs. For example, conventional αß T cells develop from DP cells after partial-agonist T cell receptor (TCR) interactions with self-peptide/MHC, whereas unconventional αß T cells, such as TCRαß(+)CD8αα(+) intraepithelial lymphocytes (IELs), require full-agonist TCR interactions. Despite this, DP cells appear homogeneous, and it remains unclear how distinct TCR signalling instructs distinct developmental outcomes. Moreover, whether TCR signals at earlier stages of development, for example in CD4(-)CD8(-) double negative (DN) cells, impact on later fate decisions is presently unknown. Here, we assess four strains of mice that display altered TCR signal strength in DN cells, which correlates with altered generation of unconventional TCRαß(+)CD8αα(+) IELs. FVB/n mice (compared to C57BL/6 animals) and mice with altered preTCRα (pTα) expression, both displayed weaker TCR signalling in DN cells, an inefficient DN-to-DP transition, and reduced contribution of TCRαß(+)CD8αα(+) IELs to gut epithelium. Conversely, TCRαß(+)CD8αα(+) IEL development was favoured in mice with increased TCR signal strength in DN cells. Collectively, these data suggest TCR signal strength in DN cells directly impacts on subsequent DP cell differentiation, fundamentally altering the potential of thymocyte progenitors to adopt conventional versus unconventional T cell fates.
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Linfocitos T CD8-positivos/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Timocitos/metabolismo , Animales , Biomarcadores , Inmunofenotipificación , Linfocitos Intraepiteliales/metabolismo , Ratones , Ratones Noqueados , Ratones Transgénicos , Células T Invariantes Asociadas a Mucosa/metabolismo , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismoRESUMEN
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.
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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
Despite a growing appreciation of γδ T cell contributions to numerous immune responses, the mechanisms that underpin their thymic development remain poorly understood. Here, using precursor/product relationships, we identify thymic stages in two distinct developmental pathways that generate γδ T cells pre-committed to subsequent secretion of either IL-17A or IFNγ. Importantly, this framework for tracking γδ T cell development has permitted definitive assessment of TCRγδ signal strength in commitment to γδ T cell effector fate; increased TCRγδ signal strength profoundly prohibited the development of all IL-17A-secreting γδ T cells, regardless of Vγ usage, but promoted the development of γδ progenitors along the IFNγ pathway. This clarifies the recently debated role of TCRγδ signal strength in commitment to distinct γδ T cell effector fates and proposes an alternate methodology for the study of γδ T cell development.
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Interleucina-17/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Linfocitos T/fisiología , Animales , Diferenciación Celular , Células Cultivadas , Femenino , Ratones Endogámicos C57BL , Timo/citologíaRESUMEN
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.
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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
γδ T cells play a role in a wide range of diseases such as autoimmunity and cancer. The majority of circulating human γδ T lymphocytes express a Vγ9Vδ2+ (Vδ2+) T cell receptor (TCR) and following activation release pro-inflammatory cytokines. In this study, we show that IFNγ, produced by Vδ2+ cells, activates mesenchymal stem cell (MSC)-mediated immunosupression, which in turn exerts a negative feedback mechanism on γδ T cell function ranging from cytokine production to proliferation. Importantly, this modulatory effect is limited to a short period of time (<24 hours) post-T cell activation, after which MSCs can no longer exert their immunoregulatory capacity. Using genetically modified MSCs with the IFNγ receptor 1 constitutively silenced, we demonstrate that IFNγ is essential to this process. Activated γδ T cells induce expression of several factors by MSCs that participate in the depletion of amino acids. In particular, we show that indolamine 2,3-dioxygenase (IDO), an enzyme involved in L-tryptophan degradation, is responsible for MSC-mediated immunosuppression of Vδ2+ T cells. Thus, our data demonstrate that γδ T cell responses can be immuno-modulated by different signals derived from MSC.