RESUMEN
CD8+ T cells that respond to chronic viral infections or cancer are characterized by the expression of inhibitory receptors such as programmed cell death protein 1 (PD-1) and by the impaired production of cytokines. This state of restrained functionality-which is referred to as T cell exhaustion1,2-is maintained by precursors of exhausted T (TPEX) cells that express the transcription factor T cell factor 1 (TCF1), self-renew and give rise to TCF1- exhausted effector T cells3-6. Here we show that the long-term proliferative potential, multipotency and repopulation capacity of exhausted T cells during chronic infection are selectively preserved in a small population of transcriptionally distinct CD62L+ TPEX cells. The transcription factor MYB is not only essential for the development of CD62L+ TPEX cells and maintenance of the antiviral CD8+ T cell response, but also induces functional exhaustion and thereby prevents lethal immunopathology. Furthermore, the proliferative burst in response to PD-1 checkpoint inhibition originates exclusively from CD62L+ TPEX cells and depends on MYB. Our findings identify CD62L+ TPEX cells as a stem-like population that is central to the maintenance of long-term antiviral immunity and responsiveness to immunotherapy. Moreover, they show that MYB is a transcriptional orchestrator of two fundamental aspects of exhausted T cell responses: the downregulation of effector function and the long-term preservation of self-renewal capacity.
Asunto(s)
Linfocitos T CD8-positivos , Receptor de Muerte Celular Programada 1 , Proteínas Proto-Oncogénicas c-myb , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Proliferación Celular , Autorrenovación de las Células , Factor Nuclear 1-alfa del Hepatocito/metabolismo , Inmunoterapia , Selectina L/metabolismo , Células Precursoras de Linfocitos T/citología , Células Precursoras de Linfocitos T/inmunología , Receptor de Muerte Celular Programada 1/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Proteínas Proto-Oncogénicas c-myb/metabolismo , Virus/inmunologíaRESUMEN
CD8+ T cell responses to pulmonary challenges are primed by lung migratory dendritic cells (mDCs), which capture antigens in the lungs and migrate to the lung-draining mediastinal lymph node (med-LN) to activate T cells. The lungs and the spleen are not connected by the lymphatic vasculature. Thus, the current paradigm suggests that, in response to respiratory virus infections that are restricted to the respiratory tract, priming of T cell responses by lung mDCs takes place entirely in the med-LN. Our results challenge this "LN-centric" paradigm by demonstrating that, during influenza virus infection, lung mDCs egress the med-LN and traffic to the spleen, where they prime influenza-specific CD8+ T cells. CD8+ T cells primed in the spleen are transcriptionally distinct and have enhanced ability to differentiate into long-lived memory cells compared with med-LNprimed counterparts. Thus, our data identify a lung mDC trafficking pathway that connects the lungs with the spleen.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Factor Nuclear 1-alfa del Hepatocito/inmunología , Pulmón/inmunología , Infecciones por Orthomyxoviridae/inmunología , Bazo/inmunología , Animales , Movimiento Celular/inmunología , Células Dendríticas/inmunología , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células Precursoras de Linfocitos T/inmunologíaRESUMEN
Hepatitis C virus (HCV)-specific CD8+ T cell response is essential in natural HCV infection control, but it becomes exhausted during persistent infection. Nowadays, chronic HCV infection can be resolved by direct acting anti-viral treatment, but there are still some non-responders that could benefit from CD8+ T cell response restoration. To become fully reactive, T cell needs the complete release of T cell receptor (TCR) signalling but, during exhaustion this is blocked by the PD-1 effect on CD28 triggering. The T cell pool sensitive to PD-1 modulation is the progenitor subset but not the terminally differentiated effector population. Nevertheless, the blockade of PD-1/PD-L1 checkpoint cannot be always enough to restore this pool. This is due to the HCV ability to impair other co-stimulatory mechanisms and metabolic pathways and to induce a pro-apoptotic state besides the TCR signalling impairment. In this sense, gamma-chain receptor cytokines involved in memory generation and maintenance, such as low-level IL-2, IL-7, IL-15, and IL-21, might carry out a positive effect on metabolic reprogramming, apoptosis blockade and restoration of co-stimulatory signalling. This review sheds light on the role of combinatory immunotherapeutic strategies to restore a reactive anti-HCV T cell response based on the mixture of PD-1 blocking plus IL-2/IL-7/IL-15/IL-21 treatment.
Asunto(s)
Antígeno B7-H1/genética , Hepacivirus/inmunología , Hepatitis C Crónica/tratamiento farmacológico , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunoterapia/métodos , Receptor de Muerte Celular Programada 1/genética , Receptores de Antígenos de Linfocitos T gamma-delta/genética , Anticuerpos Monoclonales/uso terapéutico , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Regulación de la Expresión Génica , Hepacivirus/patogenicidad , Hepatitis C Crónica/genética , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/virología , Interacciones Huésped-Patógeno/efectos de los fármacos , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Humanos , Inmunidad Celular/efectos de los fármacos , Interleucinas/genética , Interleucinas/inmunología , Interleucinas/uso terapéutico , Activación de Linfocitos/efectos de los fármacos , Células Precursoras de Linfocitos T/efectos de los fármacos , Células Precursoras de Linfocitos T/inmunología , Células Precursoras de Linfocitos T/virología , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/agonistas , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Transducción de SeñalRESUMEN
T cells dynamically interact with multiple, distinct cellular subsets to determine effector and memory differentiation. Here, we developed a platform to quantify cell location in three dimensions to determine the spatial requirements that direct T cell fate. After viral infection, we demonstrated that CD8+ effector T cell differentiation is associated with positioning at the lymph node periphery. This was instructed by CXCR3 signaling since, in its absence, T cells are confined to the lymph node center and alternatively differentiate into stem-like memory cell precursors. By mapping the cellular sources of CXCR3 ligands, we demonstrated that CXCL9 and CXCL10 are expressed by spatially distinct dendritic and stromal cell subsets. Unlike effector cells, retention of stem-like memory precursors in the paracortex is associated with CCR7 expression. Finally, we demonstrated that T cell location can be tuned, through deficiency in CXCL10 or type I interferon signaling, to promote effector or stem-like memory fates.
Asunto(s)
Infecciones por Arenaviridae/metabolismo , Linfocitos T CD8-positivos/metabolismo , Diferenciación Celular , Quimiocina CXCL10/metabolismo , Quimiocina CXCL9/metabolismo , Memoria Inmunológica , Ganglios Linfáticos/metabolismo , Células Precursoras de Linfocitos T/metabolismo , Receptores CXCR3/metabolismo , Animales , Infecciones por Arenaviridae/genética , Infecciones por Arenaviridae/inmunología , Infecciones por Arenaviridae/virología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Linaje de la Célula , Células Cultivadas , Quimiocina CXCL10/genética , Quimiocina CXCL9/genética , Quimiotaxis de Leucocito , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Modelos Animales de Enfermedad , Interacciones Huésped-Patógeno , Interferón Tipo I/metabolismo , Ligandos , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/virología , Virus de la Coriomeningitis Linfocítica/inmunología , Virus de la Coriomeningitis Linfocítica/patogenicidad , Ratones Endogámicos C57BL , Ratones Noqueados , Fenotipo , Células Precursoras de Linfocitos T/inmunología , Células Precursoras de Linfocitos T/virología , Receptor de Interferón alfa y beta/genética , Receptor de Interferón alfa y beta/metabolismo , Receptores CCR7/metabolismo , Receptores CXCR3/genética , Transducción de Señal , Nicho de Células Madre , Células del Estroma/inmunología , Células del Estroma/metabolismoRESUMEN
TCRαß+ CD8α+ CD8ß- intestinal intraepithelial lymphocytes (CD8αα IEL) are gut T cells that maintain barrier surface homeostasis. Most CD8αα IEL are derived from thymic precursors (IELp) through a mechanism referred to as clonal diversion. In this model, self-reactive thymocytes undergo deletion in the presence of CD28 costimulation, but in its absence undergo diversion to the IEL fate. While previous reports showed that IELp were largely ß2m dependent, the APC that drive the development of these cells are poorly defined. We found that both CD80 and CD86 restrain IELp development, and conventional DCs play a prominent role. We sought to define a CD80/86 negative, MHCI positive APC that supports the development to the IEL lineage. Chimera studies showed that MHCI needs to be expressed on hematopoietic APC for selection. As thymic hematopoietic APC are heterogeneous in their expression of MHCI and costimulatory molecules, we identified four thymic APC types that were CD80/86neg/low and MHCI+ . However, selective depletion of ß2m in individual APC suggested functional redundancy. Thus, while hematopoietic APC play a critical role in clonal diversion, no single APC subset is specialized to promote the CD8αα IEL fate.
Asunto(s)
Selección Clonal Mediada por Antígenos , Linfocitos Intraepiteliales/inmunología , Linfocitos Intraepiteliales/metabolismo , Linfopoyesis , Células Precursoras de Linfocitos T/inmunología , Células Precursoras de Linfocitos T/metabolismo , Timo/citología , Animales , Biomarcadores , Diferenciación Celular , Genes MHC Clase I , Inmunofenotipificación , Linfocitos Intraepiteliales/citología , Linfopoyesis/genética , Linfopoyesis/inmunología , Ratones , Células Precursoras de Linfocitos T/citología , Timocitos/citología , Timocitos/inmunología , Timocitos/metabolismoRESUMEN
During chronic infection and cancer, a self-renewing CD8+ T cell subset maintains long-term immunity and is critical to the effectiveness of immunotherapy. These stem-like CD8+ T cells diverge from other CD8+ subsets early after chronic viral infection. However, pathways guarding stem-like CD8+ T cells against terminal exhaustion remain unclear. Here, we show that the gene encoding transcriptional repressor BACH2 is transcriptionally and epigenetically active in stem-like CD8+ T cells but not terminally exhausted cells early after infection. BACH2 overexpression enforced stem-like cell fate, whereas BACH2 deficiency impaired stem-like CD8+ T cell differentiation. Single-cell transcriptomic and epigenomic approaches revealed that BACH2 established the transcriptional and epigenetic programs of stem-like CD8+ T cells. In addition, BACH2 suppressed the molecular program driving terminal exhaustion through transcriptional repression and epigenetic silencing. Thus, our study reveals a new pathway that enforces commitment to stem-like CD8+ lineage and prevents an alternative terminally exhausted cell fate.
Asunto(s)
Infecciones por Arenaviridae/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Linfocitos T CD8-positivos/metabolismo , Diferenciación Celular , Epigénesis Genética , Células Precursoras de Linfocitos T/metabolismo , Transcripción Genética , Animales , Infecciones por Arenaviridae/genética , Infecciones por Arenaviridae/inmunología , Infecciones por Arenaviridae/virología , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/deficiencia , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Linaje de la Célula , Células Cultivadas , Enfermedad Crónica , Modelos Animales de Enfermedad , Interacciones Huésped-Patógeno , Virus de la Coriomeningitis Linfocítica/inmunología , Virus de la Coriomeningitis Linfocítica/patogenicidad , Ratones Endogámicos C57BL , Ratones Noqueados , Fenotipo , Células Precursoras de Linfocitos T/inmunología , Células Precursoras de Linfocitos T/virología , Transducción de SeñalRESUMEN
The developmental origins of memory T cells remain incompletely understood. During the expansion phase of acute viral infection, we identified a distinct subset of virus-specific CD8+ T cells that possessed distinct characteristics including expression of CD62L, T cell factor 1 (TCF-1), and Eomesodermin; relative quiescence; expression of activation markers; and features of limited effector differentiation. These cells were a quantitatively minor subpopulation of the TCF-1+ pool and exhibited self-renewal, heightened DNA damage surveillance activity, and preferential long-term recall capacity. Despite features of memory and somewhat restrained proliferation during the expansion phase, this subset displayed evidence of stronger TCR signaling than other responding CD8+ T cells, coupled with elevated expression of multiple inhibitory receptors including programmed cell death 1 (PD-1), lymphocyte activating gene 3 (LAG-3), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), CD5, and CD160. Genetic ablation of PD-1 and LAG-3 compromised the formation of this CD62Lhi TCF-1+ subset and subsequent CD8+ T cell memory. Although central memory phenotype CD8+ T cells were formed in the absence of these cells, subsequent memory CD8+ T cell recall responses were compromised. Together, these results identify an important link between genome integrity maintenance and CD8+ T cell memory. Moreover, the data indicate a role for inhibitory receptors in preserving key memory CD8+ T cell precursors during initial activation and differentiation. Identification of this rare subpopulation within the memory CD8+ T cell precursor pool may help reconcile models of the developmental origin of long-term CD8+ T cell memory.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Listeriosis/inmunología , Coriomeningitis Linfocítica/inmunología , Células T de Memoria/inmunología , Células Precursoras de Linfocitos T/inmunología , Animales , Antígenos CD/genética , Linfocitos T CD8-positivos/metabolismo , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Daño del ADN/inmunología , Modelos Animales de Enfermedad , Femenino , Factor Nuclear 1-alfa del Hepatocito/metabolismo , Humanos , Memoria Inmunológica/genética , Listeria monocytogenes/inmunología , Listeriosis/microbiología , Activación de Linfocitos , Coriomeningitis Linfocítica/virología , Virus de la Coriomeningitis Linfocítica/inmunología , Masculino , Células T de Memoria/metabolismo , Ratones , Ratones Noqueados , Células Precursoras de Linfocitos T/metabolismo , Receptor de Muerte Celular Programada 1/genética , Proteína del Gen 3 de Activación de LinfocitosRESUMEN
Runt domain-related (Runx) transcription factors are essential for early T cell development in mice from uncommitted to committed stages. Single and double Runx knockouts via Cas9 show that target genes responding to Runx activity are not solely controlled by the dominant factor, Runx1. Instead, Runx1 and Runx3 are coexpressed in single cells; bind to highly overlapping genomic sites; and have redundant, collaborative functions regulating genes pivotal for T cell development. Despite stable combined expression levels across pro-T cell development, Runx1 and Runx3 preferentially activate and repress genes that change expression dynamically during lineage commitment, mostly activating T-lineage genes and repressing multipotent progenitor genes. Furthermore, most Runx target genes are sensitive to Runx perturbation only at one stage and often respond to Runx more for expression transitions than for maintenance. Contributing to this highly stage-dependent gene regulation function, Runx1 and Runx3 extensively shift their binding sites during commitment. Functionally distinct Runx occupancy sites associated with stage-specific activation or repression are also distinguished by different patterns of partner factor cobinding. Finally, Runx occupancies change coordinately at numerous clustered sites around positively or negatively regulated targets during commitment. This multisite binding behavior may contribute to a developmental "ratchet" mechanism making commitment irreversible.
Asunto(s)
Linaje de la Célula/inmunología , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 3 del Factor de Unión al Sitio Principal/genética , Células Precursoras de Linfocitos T/inmunología , Linfocitos T/inmunología , Transcriptoma , Animales , Diferenciación Celular , Linaje de la Célula/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal/inmunología , Subunidad alfa 3 del Factor de Unión al Sitio Principal/inmunología , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Subunidad alfa del Receptor de Interleucina-2/genética , Subunidad alfa del Receptor de Interleucina-2/inmunología , Masculino , Ratones , Células Precursoras de Linfocitos T/citología , Cultivo Primario de Células , Proteínas Represoras/genética , Proteínas Represoras/inmunología , Linfocitos T/clasificación , Linfocitos T/citología , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/inmunologíaRESUMEN
Persisting stimulation can skew CD8 T cells towards a hypofunctional state commonly referred to as T cell exhaustion. This functional attenuation likely constitutes a mechanism which evolved to balance T cell mediated viral control versus overwhelming immunopathology. Here, we highlight the recent progress in defining the genetic mechanisms and factors shaping the differentiation of exhausted CD8 T cells. We review how the transcription factor Tox imposes an exhausted phenotype in the Tcf1+ progenitors and how CD4 help fine-tunes the effector subsets that emerge from this progenitor population. Both processes critically shape the spectrum of effector function performed by CD8 T cells and the level of resulting virus control. Finally, we discuss how these insights can be exploited to boost the immune response in chronic infection and cancer.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Proteínas del Grupo de Alta Movilidad/metabolismo , Proteínas de Homeodominio/metabolismo , Subgrupos de Linfocitos T/inmunología , Virosis/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Enfermedad Crónica , Epigénesis Genética , Proteínas del Grupo de Alta Movilidad/genética , Proteínas de Homeodominio/genética , Humanos , Memoria Inmunológica , Ratones , Células Precursoras de Linfocitos T/inmunología , Células Precursoras de Linfocitos T/metabolismo , Subgrupos de Linfocitos T/metabolismo , Linfocitos T Colaboradores-Inductores/inmunología , Transcripción GenéticaRESUMEN
CD8+ T cells responding to chronic infections or tumors acquire an 'exhausted' state associated with elevated expression of inhibitory receptors, including PD-1, and impaired cytokine production. Exhausted T cells are continuously replenished by T cells with precursor characteristics that self-renew and depend on the transcription factor TCF1; however, their developmental requirements are poorly understood. In the present study, we demonstrate that high antigen load promoted the differentiation of precursor T cells, which acquired hallmarks of exhaustion within days of infection, whereas early effector cells retained polyfunctional features. Early precursor T cells showed epigenetic imprinting characteristic of T cell receptor-dependent transcription factor binding and were restricted to the generation of cells displaying exhaustion characteristics. Transcription factors BACH2 and BATF were key regulators with opposing functions in the generation of early precursor T cells. Overall, we demonstrate that exhaustion manifests first in TCF1+ precursor T cells and is propagated subsequently to the pool of antigen-specific T cells.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Coriomeningitis Linfocítica/inmunología , Virus de la Coriomeningitis Linfocítica/fisiología , Células Precursoras de Linfocitos T/inmunología , Animales , Diferenciación Celular , Autorrenovación de las Células , Células Cultivadas , Enfermedad Crónica , Anergia Clonal , Epigénesis Genética , Factor Nuclear 1-alfa del Hepatocito/metabolismo , Tolerancia Inmunológica , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Receptores de Antígenos de Linfocitos T/metabolismo , Especificidad del Receptor de Antígeno de Linfocitos TRESUMEN
An increasing body of evidence emphasizes the role of tissue-resident memory T cells (TRM) in the defense against recurring pathogens and malignant neoplasms. However, little is known with regard to the origin of these cells and their kinship to other CD8+ T cell compartments. To address this issue, we followed the antigen-specific progeny of individual naive CD8+ T cells to the T effector (TEFF), T circulating memory (TCIRCM), and TRM pools by lineage-tracing and single-cell transcriptome analysis. We demonstrate that a subset of T cell clones possesses a heightened capacity to form TRM, and that enriched expression of TRM-fate-associated genes is already apparent in the circulating TEFF offspring of such clones. In addition, we demonstrate that the capacity to generate TRM is permanently imprinted at the clonal level, before skin entry. Collectively, these data provide compelling evidence for early stage TRM fate decisions and the existence of committed TRM precursor cells in the circulatory TEFF compartment.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Memoria Inmunológica , Células Precursoras de Linfocitos T/inmunología , Animales , Linaje de la Célula , Perfilación de la Expresión Génica , Ratones , Ratones Endogámicos C57BLRESUMEN
Robust CD8+ T cell memory is essential for long-term protective immunity but is often compromised in cancer, where T cell exhaustion leads to loss of memory precursors. Immunotherapy via checkpoint blockade may not effectively reverse this defect, potentially underlying disease relapse. Here we report that mice with a CD8+ T cell-restricted neuropilin-1 (NRP1) deletion exhibited substantially enhanced protection from tumor rechallenge and sensitivity to anti-PD1 immunotherapy, despite unchanged primary tumor growth. Mechanistically, NRP1 cell-intrinsically limited the self-renewal of the CD44+PD1+TCF1+TIM3- progenitor exhausted T cells, which was associated with their reduced ability to induce c-Jun/AP-1 expression on T cell receptor restimulation, a mechanism that may contribute to terminal T cell exhaustion at the cost of memory differentiation in wild-type tumor-bearing hosts. These data indicate that blockade of NRP1, a unique 'immune memory checkpoint', may promote the development of long-lived tumor-specific Tmem that are essential for durable antitumor immunity.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Proteínas de Punto de Control Inmunitario/metabolismo , Melanoma Experimental/inmunología , Neuropilina-1/metabolismo , Células Precursoras de Linfocitos T/inmunología , Animales , Línea Celular Tumoral , Humanos , Proteínas de Punto de Control Inmunitario/genética , Tolerancia Inmunológica , Inmunidad , Memoria Inmunológica , Ratones , Ratones Noqueados , Neuropilina-1/genética , Receptor de Muerte Celular Programada 1/metabolismo , Transducción de SeñalRESUMEN
The memory CD8 T-cell pool must select for clones that bind immunodominant epitopes with high affinity to efficiently counter reinfection. At the same time, it must retain a level of clonal diversity to allow recognition of pathogens with mutated epitopes. How the level of diversity within the memory pool is controlled is unclear, especially in the context of a selective drive for antigen affinity. We find that preservation of clones that bind the activating antigen with low affinity depends on expression of the transcription factor Eomes in the first days after antigen encounter. Eomes is induced at low activating signal strength and directly drives transcription of the prosurvival protein Bcl-2. At higher signal intensity, T-bet is induced which suppresses Bcl-2 and causes a relative survival advantage for cells of low affinity. Clones activated with high-affinity antigen form memory largely independent of Eomes and have a proliferative advantage over clones that bind the same antigen with low affinity. This causes high-affinity clones to prevail in the memory pool, despite their relative survival deficit. Genetic or therapeutic targeting of the Eomes/Bcl-2 axis reduces the clonal diversity of the memory pool, which diminishes its ability to respond to pathogens carrying mutations in immunodominant epitopes. Thus, we demonstrate on a molecular level how sufficient diversity of the memory pool is established in an environment of affinity-based selection.
Asunto(s)
Apoptosis/inmunología , Linfocitos T CD8-positivos/inmunología , Memoria Inmunológica , Proteínas de Dominio T Box/inmunología , Animales , Variación Antigénica/inmunología , Supervivencia Celular/inmunología , Células Cultivadas , Selección Clonal Mediada por Antígenos/genética , Selección Clonal Mediada por Antígenos/inmunología , Regulación de la Expresión Génica/inmunología , Activación de Linfocitos , Ratones , Células Precursoras de Linfocitos T/inmunología , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/inmunología , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Transducción de Señal , Proteínas de Dominio T Box/genéticaRESUMEN
DO (HLA-DO, in human; murine H2-O) is a highly conserved nonclassical major histocompatibility complex class II (MHC II) accessory molecule mainly expressed in the thymic medulla and B cells. Previous reports have suggested possible links between DO and autoimmunity, Hepatitis C (HCV) infection, and cancer, but the mechanism of how DO contributes to these diseases remains unclear. Here, using a combination of various in vivo approaches, including peptide elution, mixed lymphocyte reaction, T-cell receptor (TCR) deep sequencing, tetramer-guided naïve CD4 T-cell precursor enumeration, and whole-body imaging, we report that DO affects the repertoire of presented self-peptides by B cells and thymic epithelium. DO induces differential effects on epitope presentation and thymic selection, thereby altering CD4 T-cell precursor frequencies. Our findings were validated in two autoimmune disease models by demonstrating that lack of DO increases autoreactivity and susceptibility to autoimmune disease development.
Asunto(s)
Enfermedades Autoinmunes/genética , Predisposición Genética a la Enfermedad/genética , Antígenos de Histocompatibilidad Clase II/genética , Animales , Células Presentadoras de Antígenos/inmunología , Enfermedades Autoinmunes/inmunología , Autoinmunidad/genética , Linfocitos B/inmunología , Linfocitos T CD4-Positivos/inmunología , Colágeno/administración & dosificación , Colágeno/inmunología , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Glicoproteína Mielina-Oligodendrócito/inmunología , Péptidos/inmunología , Células Precursoras de Linfocitos T/inmunología , Timo/inmunologíaRESUMEN
The diversity of the naïve T cell repertoire drives the replenishment potential and capacity of memory T cells to respond to immune challenges. Attrition of the immune system is associated with an increased prevalence of pathologies in aged individuals, but whether stem cell memory T lymphocytes (TSCM) contribute to such attrition is still unclear. Using single cells RNA sequencing and high-dimensional flow cytometry, we demonstrate that TSCM heterogeneity results from differential engagement of Wnt signaling. In humans, aging is associated with the coupled loss of Wnt/ß-catenin signature in CD4 TSCM and systemic increase in the levels of Dickkopf-related protein 1, a natural inhibitor of the Wnt/ß-catenin pathway. Functional assays support recent thymic emigrants as the precursors of CD4 TSCM. Our data thus hint that reversing TSCM defects by metabolic targeting of the Wnt/ß-catenin pathway may be a viable approach to restore and preserve immune homeostasis in the context of immunological history.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Células Precursoras de Linfocitos T/inmunología , Vía de Señalización Wnt/inmunología , Envejecimiento/inmunología , Animales , Antígenos CD/genética , Antígenos CD/metabolismo , Perfilación de la Expresión Génica , Infecciones por VIH/inmunología , Humanos , Memoria Inmunológica , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Ratones , Timo/inmunología , Vía de Señalización Wnt/genética , beta Catenina/inmunologíaRESUMEN
The etiology of classical Hodgkin lymphoma (cHL) is largely unknown. High serum CD30-levels are associated with increased risk of cHL. Epstein-Barr virus (EBV) is detectable in the tumor cells in 1/3 of cHL cases in the Western world. The PD-1 pathway (T-cell inflamed immune response) might contribute to the pathogenesis by enabling pre-malignant CD30+ or EBV + cells to evade immune surveillance. We aimed to investigate if high infiltrations of CD30+, PD-1+, PD-L1+ and EBV + cells in benign lymph nodes from patients that later develop cHL (cases) (n = 15) were associated with risk of cHL compared to controls (n = 45) with benign lymph nodes from patients that did not develop cHL. Pathology registries including 3500 cH L patients were screened. Lymph nodes were stained with immunohistochemistry and in situ hybridization and the risk for cHL calculated with logistic regression. High CD30-expression by B- and T-cells was associated with a decreased risk of cHL [(OR = 0.10, 95 % CI:0.03-0.39) and (OR = 0.13, 95 % CI:0.01-0.71), respectively], which remained significant for CD30 + B-cells (OR = 0.15, 95 % CI:0.03-0.60) in multivariate analyses. Amount of PD-1+, PD-L1+ and EBV + cells were not statistically significantly associated with risk of cHL. However, the amount of PD-L1+ leukocytes tended to be higher in cases later developing cHL (OR = 2.84, 95 % CI:0.61-12.61). High proportions of potential precursors to cHL, i.e. CD30 + B-cells in benign lymph nodes are not associated with an increased risk of cHL, while a tendency for a T-cell inflamed immune response, i.e. abundant PD-L1+ cells, was observed in biopsies taken prior to the cHL diagnosis.
Asunto(s)
Antígeno B7-H1/metabolismo , Infecciones por Virus de Epstein-Barr/inmunología , Herpesvirus Humano 4/fisiología , Enfermedad de Hodgkin/inmunología , Inflamación/inmunología , Antígeno Ki-1/metabolismo , Ganglios Linfáticos/metabolismo , Lesiones Precancerosas/inmunología , Células Precursoras de Linfocitos T/inmunología , Linfocitos T/inmunología , Adulto , Biomarcadores de Tumor/metabolismo , Femenino , Enfermedad de Hodgkin/diagnóstico , Humanos , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Lesiones Precancerosas/diagnóstico , Pronóstico , Receptor de Muerte Celular Programada 1/metabolismo , Sistema de Registros , RiesgoRESUMEN
The maternal immune system needs to be tolerant of allogeneic fetal tissue for reproductive success. The regulatory immune cell network plays an essential role in maintaining maternal tolerance to the fetus. We herein demonstrate in a green fluorescent protein (GFP)/IL-10 reporter mouse system that unique IL-10-expressing cells exist presumably in chorionic villi within the placenta. Flow cytometric analysis revealed that these IL-10- expressing cells exhibit a unique CD19 negative, CD3 negative, and B220 positive phenotype. Interestingly, these cells were enriched during in vitro culture, but well-known stimuli for T cells and B cells failed to enhance their growth, suggesting that the CD19- CD3- B220+ cells were self renewing. Unexpectedly, in an adoptive cell trans fer experiment, IL-10 production was detected in Sca-1+ CD4+ CD25+ regulatory T cells (Treg). To our knowledge, this is the first report to identify IL-10-producing CD19- CD3- B220+ cells in the fetus. These cells may rep resent a potential progenitor of Sca-1+ Treg or pluripotent precursor cells for immune tolerance.
Asunto(s)
Interleucina-10/metabolismo , Placenta/metabolismo , Células Precursoras de Linfocitos T/metabolismo , Linfocitos T Reguladores/metabolismo , Traslado Adoptivo , Animales , Antígenos CD19/metabolismo , Antígenos Ly/metabolismo , Complejo CD3/metabolismo , Linaje de la Célula , Células Cultivadas , Femenino , Genes Reporteros , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/genética , Huésped Inmunocomprometido , Interleucina-10/genética , Antígenos Comunes de Leucocito/metabolismo , Proteínas de la Membrana/metabolismo , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Transgénicos , Fenotipo , Placenta/citología , Placenta/inmunología , Células Precursoras de Linfocitos T/inmunología , Células Precursoras de Linfocitos T/trasplante , Embarazo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/trasplanteRESUMEN
Natural intraepithelial lymphocytes (IELs) are thymus-derived adaptive immune cells, which are important contributors to intestinal immune homeostasis. Similar to other innate-like T cells, they are induced in the thymus through high-avidity interaction that would otherwise lead to clonal deletion in conventional CD4 and CD8 T cells. By applying single-cell RNA-sequencing (scRNA-seq) on a heterogeneous population of thymic CD4-CD8αß-TCRαß+NK1.1- IEL precursors (NK1.1- IELPs), we define a developmental trajectory that can be tracked based on the sequential expression of CD122 and T-bet. Moreover, we identify the Id proteins Id2 and Id3 as a novel regulator of IELP development and show that all NK1.1- IELPs progress through a PD-1 stage that precedes the induction of T-bet. The transition from PD-1 to T-bet is regulated by the transcription factor C-Myc, which has far reaching effects on cell cycle, energy metabolism, and the translational machinery during IELP development. In summary, our results provide a high-resolution molecular framework for thymic IEL development of NK1.1- IELPs and deepen our understanding of this still elusive cell type.
Asunto(s)
Linfocitos Intraepiteliales/inmunología , Células Precursoras de Linfocitos T/inmunología , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas de Dominio T Box/metabolismo , Timo/inmunología , Animales , Antígenos Ly/metabolismo , Células Cultivadas , Regulación de la Expresión Génica , Inmunidad Innata , Proteína 2 Inhibidora de la Diferenciación/genética , Proteína 2 Inhibidora de la Diferenciación/metabolismo , Proteínas Inhibidoras de la Diferenciación/genética , Proteínas Inhibidoras de la Diferenciación/metabolismo , Subunidad beta del Receptor de Interleucina-2/genética , 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 , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Proteínas de Dominio T Box/genéticaRESUMEN
OBJECTIVE: To determine circulating follicular T helper (Tfh) cell precursor and its relationship with clinical characteristics in idiopathic inflammatory myopathy (IIM). METHODS: The study population included 47 patients with IIM and 30 healthy controls. Circulating CD4+ CXCR5+ CCR7lo PD-1hi T cells and intracellular interleukin (IL)-21 were assessed by flow cytometry. Serum IL-21 levels were measured by enzyme-linked immunosorbent assay. The disease activity was evaluated using myositis disease activity assessment visual analog scales (VAS) as well as muscle and physician global assessment (PGA). RESULTS: The percentage of the CCR7lo PD-1hi subset cells within CD4+ CXCR5+ T cells was significantly increased in patients with IIM compared to that in healthy controls (14.3 ± 6.5 vs 11.4 ± 2.6, P = .009). Patients with higher percentages of CCR7lo PD-1hi subsets presented with higher PGA VAS (P = .000), muscle VAS (P = .000), as well as serum creatinine kinase (CK) levels (P = .000) than those with lower percentages of CCR7lo PD-1hi subsets. IL-21 expression significantly increased in CD4+ CXCR5+ CCR7lo PD-1hi T cells in patients with IIM compared to that in healthy controls (26.07 ± 7.38 vs 19.25 ± 5.67, P = .001). Meanwhile, both the CCR7lo PD-1hi subset and intracellular IL-21 expression in IIM patients showed significantly positive correlation with PGA VAS, muscle VAS and serum CK levels. Circulating CD4+ CXCR5+ CCR7lo PD-1hi T cells and intracellular IL-21 decreased significantly when disease was improved (P = .018; P = .028). CONCLUSION: The percentage of circulating CCR7lo PD-1hi subset among total CD4+ CXCR5+ T cells and intracellular IL-21 expression expanded and showed significant correlation with disease activity in IIM. The circulating follicular helper T cell precursor may be involved in the pathogenesis, especially muscle injury in IIM.
Asunto(s)
Proliferación Celular , Miositis/inmunología , Células Precursoras de Linfocitos T/inmunología , Receptor de Muerte Celular Programada 1/sangre , Receptores CCR7/sangre , Receptores CXCR5/sangre , Linfocitos T Colaboradores-Inductores/inmunología , Adulto , Anciano , Recuento de Linfocito CD4 , Estudios de Casos y Controles , Femenino , Citometría de Flujo , Humanos , Inmunofenotipificación , Interleucinas/sangre , Masculino , Persona de Mediana Edad , Miositis/sangre , Miositis/diagnóstico , Células Precursoras de Linfocitos T/metabolismo , Pronóstico , Linfocitos T Colaboradores-Inductores/metabolismo , Adulto JovenRESUMEN
Cytotoxic T cell immunity in response to chronic infections and tumours is maintained by a specialized population of CD8+ T cells that exhibit hallmarks of both exhausted and memory cells and give rise to terminally differentiated exhausted effector cells that contribute to viral or tumour control. Importantly, recent work suggests these cells, which we refer to as 'precursor exhausted' T (TPEX) cells, are responsible for the proliferative burst that generates effector T cells in response to immune checkpoint blockade targeting programmed cell death 1 (PD1), and increased TPEX cell frequencies have recently been linked to increased patient survival. We believe the recent discovery of TPEX cells not only represents a paradigm shift in our understanding of the mechanisms that maintain CD8+ T cell responses in chronic infections and tumours but also opens up unexpected avenues for the development of new and innovative therapeutic approaches. In this Opinion article, we discuss the differentiation and function of TPEX cells and suggest that targeting these cells may be key for successful immunotherapy.