RESUMO
Maternal decidual NK (dNK) cells promote placentation, but how they protect against placental infection while maintaining fetal tolerance is unclear. Here we show that human dNK cells highly express the antimicrobial peptide granulysin (GNLY) and selectively transfer it via nanotubes to extravillous trophoblasts to kill intracellular Listeria monocytogenes (Lm) without killing the trophoblast. Transfer of GNLY, but not other cell death-inducing cytotoxic granule proteins, strongly inhibits Lm in human placental cultures and in mouse and human trophoblast cell lines. Placental and fetal Lm loads are lower and pregnancy success is greatly improved in pregnant Lm-infected GNLY-transgenic mice than in wild-type mice that lack GNLY. This immune defense is not restricted to pregnancy; peripheral NK (pNK) cells also transfer GNLY to kill bacteria in macrophages and dendritic cells without killing the host cell. Nanotube transfer of GNLY allows dNK to protect against infection while leaving the maternal-fetal barrier intact.
Assuntos
Antígenos de Diferenciação de Linfócitos T/imunologia , Bactérias/imunologia , Movimento Celular/imunologia , Células Matadoras Naturais/imunologia , Trofoblastos/imunologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Feminino , Células HeLa , Humanos , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Placenta/imunologia , Placenta/microbiologia , Gravidez , Ratos , Células THP-1 , Trofoblastos/microbiologiaRESUMO
In coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the relationship between disease severity and the host immune response is not fully understood. Here we performed single-cell RNA sequencing in peripheral blood samples of 5 healthy donors and 13 patients with COVID-19, including moderate, severe and convalescent cases. Through determining the transcriptional profiles of immune cells, coupled with assembled T cell receptor and B cell receptor sequences, we analyzed the functional properties of immune cells. Most cell types in patients with COVID-19 showed a strong interferon-α response and an overall acute inflammatory response. Moreover, intensive expansion of highly cytotoxic effector T cell subsets, such as CD4+ effector-GNLY (granulysin), CD8+ effector-GNLY and NKT CD160, was associated with convalescence in moderate patients. In severe patients, the immune landscape featured a deranged interferon response, profound immune exhaustion with skewed T cell receptor repertoire and broad T cell expansion. These findings illustrate the dynamic nature of immune responses during disease progression.
Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Interferon Tipo I/metabolismo , Pneumonia Viral/imunologia , Receptores Imunológicos/metabolismo , Adolescente , Adulto , Idoso , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , COVID-19 , Estudos de Coortes , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Feminino , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Proteínas Ligadas por GPI/metabolismo , Humanos , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , RNA-Seq , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , SARS-CoV-2 , Índice de Gravidade de Doença , Análise de Célula ÚnicaRESUMO
The activating receptor CD226 is expressed on lymphocytes, monocytes, and platelets and promotes anti-tumor immunity in pre-clinical models. Here, we examined the role of CD226 in the function of tumor-infiltrating lymphocytes (TILs) and resistance to immunotherapy. In murine tumors, a large proportion of CD8+ TILs had decreased surface expression of CD226 and exhibited features of dysfunction, whereas CD226hi TILs were highly functional. This correlation was seen also in TILs isolated from HNSCC patients. Mutation of CD226 at tyrosine 319 (Y319) led to increased CD226 surface expression, enhanced anti-tumor immunity and improved efficacy of immune checkpoint blockade (ICB). Mechanistically, tumor-derived CD155, the ligand for CD226, initiated phosphorylation of Y319 by Src kinases, thereby enabling ubiquitination of CD226 by CBL-B, internalization, and proteasomal degradation. In pre-treatment samples from melanoma patients, CD226+CD8+ T cells correlated with improved progression-free survival following ICB. Our findings argue for the development of therapies aimed at maintaining the expression of CD226.
Assuntos
Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos T CD8-Positivos/imunologia , Receptores Virais/imunologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Células HEK293 , Humanos , Inibidores de Checkpoint Imunológico/imunologia , Imunoterapia/métodos , Células Jurkat , Linfócitos do Interstício Tumoral/imunologia , Masculino , Melanoma/imunologia , Camundongos , Camundongos Endogâmicos C57BLRESUMO
CD8+ T cells within the tumor microenvironment (TME) are exposed to various signals that ultimately determine functional outcomes. Here, we examined the role of the co-activating receptor CD226 (DNAM-1) in CD8+ T cell function. The absence of CD226 expression identified a subset of dysfunctional CD8+ T cells present in peripheral blood of healthy individuals. These cells exhibited reduced LFA-1 activation, altered TCR signaling, and a distinct transcriptomic program upon stimulation. CD226neg CD8+ T cells accumulated in human and mouse tumors of diverse origin through an antigen-specific mechanism involving the transcriptional regulator Eomesodermin (Eomes). Despite similar expression of co-inhibitory receptors, CD8+ tumor-infiltrating lymphocyte failed to respond to anti-PD-1 in the absence of CD226. Immune checkpoint blockade efficacy was hampered in Cd226-/- mice. Anti-CD137 (4-1BB) agonists also stimulated Eomes-dependent CD226 loss that limited the anti-tumor efficacy of this treatment. Thus, CD226 loss restrains CD8+ T cell function and limits the efficacy of cancer immunotherapy.
Assuntos
Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos T CD8-Positivos/imunologia , Neoplasias/imunologia , Proteínas com Domínio T/imunologia , Animais , Humanos , Inibidores de Checkpoint Imunológico/imunologia , Imunoterapia/métodos , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/terapia , Receptor de Morte Celular Programada 1/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Transcriptoma/imunologia , Microambiente Tumoral/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologiaRESUMO
Resident memory T (TRM) cells have been recently established as an important subset of memory T cells that provide early and essential protection against reinfection in the absence of circulating memory T cells. Recent findings showing that TRM expand in vivo after repeated antigenic stimulation indicate that these memory T cells are not terminally differentiated. This suggests an opportunity for in vitro TRM expansion to apply in an immunotherapy setting. However, it has also been shown that TRM may not maintain their identity and form circulating memory T cells after in vivo restimulation. Therefore, we set out to determine how TRM respond to antigenic activation in culture. Using Listeria monocytogenes and LCMV infection models, we found that TRM from the intraepithelial compartment of the small intestine expand in vitro after antigenic stimulation and subsequent resting in homeostatic cytokines. A large fraction of the expanded TRM retained their phenotype, including the expression of key TRM markers CD69 and CD103 (ITGAE). The optimal culture of TRM required low O2 pressure to maintain the expression of these and other TRM-associated molecules. Expanded TRM retained their effector capacity to produce cytokines after restimulation, but did not acquire a highly glycolytic profile indicative of effector T cells. The proteomic analysis confirmed TRM profile retention, including expression of TRM-related transcription factors, tissue retention factors, adhesion molecules, and enzymes involved in fatty acid metabolism. Collectively, our data indicate that limiting oxygen conditions supports in vitro expansion of TRM cells that maintain their TRM phenotype, at least in part, suggesting an opportunity for therapeutic strategies that require in vitro expansion of TRM.
Assuntos
Memória Imunológica , Listeria monocytogenes , Células T de Memória , Animais , Células T de Memória/imunologia , Memória Imunológica/imunologia , Camundongos , Listeria monocytogenes/imunologia , Antígenos CD/metabolismo , Antígenos CD/imunologia , Cadeias alfa de Integrinas/metabolismo , Camundongos Endogâmicos C57BL , Listeriose/imunologia , Lectinas Tipo C/metabolismo , Lectinas Tipo C/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Citocinas/metabolismo , Citocinas/imunologia , Ativação Linfocitária/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Mucosa Intestinal/imunologia , Linfócitos T CD8-Positivos/imunologia , Intestino Delgado/imunologia , Células CultivadasRESUMO
The differentiation of αßT cells from thymic precursors is a complex process essential for adaptive immunity. Here we exploited the breadth of expression data sets from the Immunological Genome Project to analyze how the differentiation of thymic precursors gives rise to mature T cell transcriptomes. We found that early T cell commitment was driven by unexpectedly gradual changes. In contrast, transit through the CD4(+)CD8(+) stage involved a global shutdown of housekeeping genes that is rare among cells of the immune system and correlated tightly with expression of the transcription factor c-Myc. Selection driven by major histocompatibility complex (MHC) molecules promoted a large-scale transcriptional reactivation. We identified distinct signatures that marked cells destined for positive selection versus apoptotic deletion. Differences in the expression of unexpectedly few genes accompanied commitment to the CD4(+) or CD8(+) lineage, a similarity that carried through to peripheral T cells and their activation, demonstrated by mass cytometry phosphoproteomics. The transcripts newly identified as encoding candidate mediators of key transitions help define the 'known unknowns' of thymocyte differentiation.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Animais , Antígenos CD/imunologia , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular/genética , Linhagem da Célula/genética , Linhagem da Célula/imunologia , Proliferação de Células , Células Cultivadas , Análise por Conglomerados , Citometria de Fluxo , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/imunologia , Antígenos de Histocompatibilidade/metabolismo , Lectinas Tipo C/imunologia , Lectinas Tipo C/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Timócitos/citologia , Timócitos/imunologia , Timócitos/metabolismo , Transcriptoma/genética , Transcriptoma/imunologiaRESUMO
Cell-mediated immunity critically depends on the localization of lymphocytes at sites of infection. While some memory T cells recirculate, a distinct lineage (resident memory T cells (T(RM) cells)) are embedded in nonlymphoid tissues (NLTs) and mediate potent protective immunity. However, the defining transcriptional basis for the establishment of T(RM) cells is unknown. We found that CD8(+) T(RM) cells lacked expression of the transcription factor KLF2 and its target gene S1pr1 (which encodes S1P1, a receptor for sphingosine 1-phosphate). Forced expression of S1P1 prevented the establishment of T(RM) cells. Cytokines that induced a T(RM) cell phenotype (including transforming growth factor-ß (TGF-ß), interleukin 33 (IL-33) and tumor-necrosis factor) elicited downregulation of KLF2 expression in a pathway dependent on phosphatidylinositol-3-OH kinase (PI(3)K) and the kinase Akt, which suggested environmental regulation. Hence, regulation of KLF2 and S1P1 provides a switch that dictates whether CD8(+) T cells commit to recirculating or tissue-resident memory populations.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Regulação para Baixo/imunologia , Memória Imunológica/imunologia , Receptores de Lisoesfingolipídeo/imunologia , Animais , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Citometria de Fluxo , Interleucina-33 , Interleucinas/farmacologia , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/imunologia , Fatores de Transcrição Kruppel-Like/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Lectinas Tipo C/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/imunologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/imunologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Lisoesfingolipídeo/genética , Receptores de Lisoesfingolipídeo/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Receptores de Esfingosina-1-Fosfato , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/imunologia , Fator de Crescimento Transformador beta/farmacologia , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Tissue-resident memory T cells (T(RM) cells) provide superior protection against infection in extralymphoid tissues. Here we found that CD103(+)CD8(+) T(RM) cells developed in the skin from epithelium-infiltrating precursor cells that lacked expression of the effector-cell marker KLRG1. A combination of entry into the epithelium plus local signaling by interleukin 15 (IL-15) and transforming growth factor-ß (TGF-ß) was required for the formation of these long-lived memory cells. Notably, differentiation into T(RM) cells resulted in the progressive acquisition of a unique transcriptional profile that differed from that of circulating memory cells and other types of T cells that permanently reside in skin epithelium. We provide a comprehensive molecular framework for the local differentiation of a distinct peripheral population of memory cells that forms a first-line immunological defense system in barrier tissues.
Assuntos
Antígenos CD/imunologia , Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , Cadeias alfa de Integrinas/imunologia , Transdução de Sinais/imunologia , Pele/imunologia , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Citometria de Fluxo , Herpes Simples/imunologia , Herpes Simples/virologia , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 1/fisiologia , Interações Hospedeiro-Patógeno/imunologia , Cadeias alfa de Integrinas/genética , Cadeias alfa de Integrinas/metabolismo , Interleucina-15/genética , Interleucina-15/imunologia , Interleucina-15/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Lectinas Tipo C/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Receptores Imunológicos/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/imunologia , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Pele/metabolismo , Pele/virologia , Transcriptoma/genética , Transcriptoma/imunologiaRESUMO
The cluster of differentiation 155 (CD155) is highly expressed on tumor cells and augments or inhibits the cytotoxic activities of natural killer (NK) cells and T cells through its receptor ligands DNAX accessory molecule 1 (DNAM-1) and T-cell immunoglobulin (Ig) and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT), respectively. Although CD155 is heavily glycosylated, the role of glycosylation of CD155 in the cytotoxic activity of effector lymphocytes remains unknown. Here, we show that the N-linked glycosylation at residue 105 (N105 glycosylation) in the first Ig-like domain of CD155 is involved in the binding of CD155 to both DNAM-1 and TIGIT. The N105 glycosylation also plays an essential role to induce signaling in both DNAM-1 and TIGIT reporter cells. Moreover, we show that the N105 glycosylation of CD155 contributes preferentially to the DNAM-1-mediated activating signal over the TIGIT-mediated inhibitory signal in NK cells. Our results demonstrated the important role of the N105 glycosylation of CD155 in DNAM-1 and TIGIT functions and shed new light on the understanding of tumor immune responses.
Assuntos
Antígenos de Diferenciação de Linfócitos T , Células Matadoras Naturais , Receptores Imunológicos , Receptores Virais , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Glicosilação , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Humanos , Receptores Virais/metabolismo , Receptores Virais/imunologia , Receptores Imunológicos/metabolismo , Receptores Imunológicos/imunologia , Ligação ProteicaRESUMO
BACKGROUND: Type 2 innate lymphoid cells (ILC2s) play a pivotal role in type 2 asthma. CD226 is a costimulatory molecule involved in various inflammatory diseases. OBJECTIVE: We aimed to investigate CD226 expression and function within human and mouse ILC2s, and to assess the impact of targeting CD226 on ILC2-mediated airway hyperreactivity (AHR). METHODS: We administered IL-33 intranasally to wild-type mice, followed by treatment with anti-CD226 antibody or isotype control. Pulmonary ILC2s were sorted for ex vivo analyses through RNA sequencing and flow cytometry. Next, we evaluated the effects of CD226 on AHR and lung inflammation in wild-type and Rag2-/- mice. Additionally, we compared peripheral ILC2s from healthy donors and asthmatic patients to ascertain the role of CD226 in human ILC2s. RESULTS: Our findings demonstrated an inducible expression of CD226 in activated ILC2s, enhancing their cytokine secretion and effector functions. Mechanistically, CD226 alters intracellular metabolism and enhances PI3K/AKT and MAPK signal pathways. Blocking CD226 ameliorates ILC2-dependent AHR in IL-33 and Alternaria alternata-induced models. Interestingly, CD226 is expressed and inducible in human ILC2s, and its blocking reduces cytokine production. Finally, we showed that peripheral ILC2s in asthmatic patients exhibited elevated CD226 expression compared to healthy controls. CONCLUSION: Our findings underscore the potential of CD226 as a novel therapeutic target in ILC2s, presenting a promising avenue for ameliorating AHR and allergic asthma.
Assuntos
Antígenos de Diferenciação de Linfócitos T , Asma , Imunidade Inata , Linfócitos , Animais , Feminino , Humanos , Masculino , Camundongos , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/genética , Asma/imunologia , Interleucina-33/imunologia , Linfócitos/imunologia , Camundongos Endogâmicos C57BL , Camundongos KnockoutRESUMO
Chronic rhinosinusitis with nasal polyps (CRSwNPs) is a heterogeneous disease characterized by local inflammation of the upper airway and sinus mucosa. T cell-mediated immune responses play irreplaceable roles in the pathogenesis of nasal polyps. CD161+ T cells have been implicated in the pathology of several diseases through cytokine production and cytotoxic activity. However, the immunological characteristics of CD161+ T cells in nasal mucosa are still not well understood, particularly in CRSwNPs. Our research revealed a notable enrichment of CD161+ T cells in nasal tissues compared to peripheral blood, with a significantly more infiltration of CD161+ T cells in CRSwNPs compared to control nasal samples. Phenotypical analysis found that CD161+ T cells predominantly co-expressed tissue-resident memory surface markers CD103, CD69, and CD45RO. CD161+CD103+ T cells demonstrated complicated effector functions, marked by elevated levels of PD-1, CTLA-4, IL-17, and IFN-γ and diminished expression of FoxP3 and CD25. Interestingly, despite CD161+ T cells was more abundant in polyp tissues compared to normal control tissues, and then further categorizing polyp samples into distinct groups based on clinical characteristics, only the recurrent CRSwNP group showed a significant reduction in CD161+CD8+ T cells compared to the primary CRSwNP group. This finding suggested the necessity for further research to comprehensively understand the underlying mechanisms and the broader significance of CD161+ T cells in the advancement and relapse of CRSwNPs.
Assuntos
Antígenos CD , Cadeias alfa de Integrinas , Subfamília B de Receptores Semelhantes a Lectina de Células NK , Pólipos Nasais , Rinossinusite , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antígenos CD/metabolismo , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Antígenos de Diferenciação de Linfócitos T/imunologia , Doença Crônica , Antígeno CTLA-4/metabolismo , Antígeno CTLA-4/imunologia , Cadeias alfa de Integrinas/metabolismo , Cadeias alfa de Integrinas/imunologia , Interferon gama/metabolismo , Interferon gama/imunologia , Interleucina-17/metabolismo , Interleucina-17/imunologia , Lectinas Tipo C , Mucosa Nasal/imunologia , Pólipos Nasais/imunologia , Subfamília B de Receptores Semelhantes a Lectina de Células NK/metabolismo , Subfamília B de Receptores Semelhantes a Lectina de Células NK/imunologia , Rinossinusite/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismoRESUMO
CD6 is a glycoprotein expressed on CD4 and CD8 T cells involved in immunoregulation. CD318 has been identified as a CD6 ligand. The role of CD318 in T cell immunity is restricted as it has only been investigated in a few mice autoimmune models but not in human diseases. CD318 expression was thought to be limited to mesenchymal-epithelial cells and, therefore, contribute to CD6-mediated T cell activation in the CD318-expressing tissue rather than through interaction with antigen-presenting cells. Here, we report CD318 expression in a subpopulation of CD318+ myeloid dendritic (mDC), whereas the other peripheral blood populations were CD318 negative. However, CD318 can be induced by activation: a subset of monocytes treated with LPS and IFNγ and in vitro monocyte derived DCs were CD318+. We also showed that recombinant CD318 inhibited T cell function. Strikingly, CD318+ DCs suppressed the proliferation of autoreactive T cells specific for GAD65, a well-known targeted self-antigen in Type 1 Diabetes (T1D). Our study provides new insight into the role of the CD318/CD6 axis in the immunopathogenesis of inflammation, suggesting a novel immunoregulatory role of CD318 in T cell-mediated autoimmune diseases and identifying a potential novel immune checkpoint inhibitor as a target for intervention in T1D which is an unmet therapeutic need.
Assuntos
Antígenos CD , Autoantígenos , Células Dendríticas , Diabetes Mellitus Tipo 1 , Ilhotas Pancreáticas , Ativação Linfocitária , Humanos , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Ativação Linfocitária/imunologia , Autoantígenos/imunologia , Antígenos CD/metabolismo , Antígenos CD/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Células Cultivadas , Glutamato DescarboxilaseRESUMO
Regulatory T (Treg) cells that express forkhead box P3 (Foxp3) are pivotal for immune tolerance. Although inflammatory mediators cause Foxp3 instability and Treg cell dysfunction, their regulatory mechanisms remain incompletely understood. Here, we show that the transfer of Treg cells deficient in the activating immunoreceptor DNAM-1 ameliorated the development of graft-versus-host disease better than did wild-type Treg cells. We found that DNAM-1 competes with T cell immunoreceptor with Ig and ITIM domains (TIGIT) in binding to their common ligand CD155 and therefore regulates TIGIT signaling to down-regulate Treg cell function without DNAM-1-mediated intracellular signaling. DNAM-1 deficiency augments TIGIT signaling; this subsequently inhibits activation of the protein kinase B-mammalian target of rapamycin complex 1 pathway, resulting in the maintenance of Foxp3 expression and Treg cell function under inflammatory conditions. These findings demonstrate that DNAM-1 regulates Treg cell function via TIGIT signaling and thus, it is a potential molecular target for augmenting Treg function in inflammatory diseases.
Assuntos
Antígenos de Diferenciação de Linfócitos T/genética , Fatores de Transcrição Forkhead/genética , Doença Enxerto-Hospedeiro/genética , Receptores Imunológicos/genética , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Animais , Antígenos de Diferenciação de Linfócitos T/imunologia , Fatores de Transcrição Forkhead/imunologia , Regulação da Expressão Gênica , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Humanos , Tolerância Imunológica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/imunologia , Receptores Imunológicos/imunologia , Receptores Virais/genética , Receptores Virais/imunologia , Transdução de Sinais , Linfócitos T Reguladores/patologia , Linfócitos T Reguladores/transplante , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/imunologia , Irradiação Corporal TotalRESUMO
T cells experience complex temporal patterns of stimulus via receptor-ligand-binding interactions with surrounding cells. From these temporal patterns, T cells are able to pick out antigenic signals while establishing self-tolerance. Although features such as duration of antigen binding have been examined, our understanding of how T cells interpret signals with different frequencies or temporal stimulation patterns is relatively unexplored. We engineered T cells to respond to light as a stimulus by building an optogenetically controlled chimeric antigen receptor (optoCAR). We discovered that T cells respond to minute-scale oscillations of activation signal by stimulating optoCAR T cells with tunable pulse trains of light. Systematically scanning signal oscillation period from 1 to 150 min revealed that expression of CD69, a T cell activation marker, reached a local minimum at a period of â¼25 min (corresponding to 5 to 15 min pulse widths). A combination of inhibitors and genetic knockouts suggest that this frequency filtering mechanism lies downstream of the Erk signaling branch of the T cell response network and may involve a negative feedback loop that diminishes Erk activity. The timescale of CD69 filtering corresponds with the duration of T cell encounters with self-peptide-presenting APCs observed via intravital imaging in mice, indicating a potential functional role for temporal filtering in vivo. This study illustrates that the T cell signaling machinery is tuned to temporally filter and interpret time-variant input signals in discriminatory ways.
Assuntos
Antígenos CD/genética , Antígenos de Diferenciação de Linfócitos T/genética , Lectinas Tipo C/genética , Transdução de Sinal Luminoso/genética , Receptores de Antígenos Quiméricos/genética , Tolerância a Antígenos Próprios , Linfócitos T/imunologia , Animais , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Brefeldina A/farmacologia , Engenharia Celular/métodos , Retroalimentação Fisiológica , Regulação da Expressão Gênica , Receptor Celular 2 do Vírus da Hepatite A/genética , Receptor Celular 2 do Vírus da Hepatite A/imunologia , Humanos , Interferon gama/genética , Interferon gama/imunologia , Células K562 , Lectinas Tipo C/imunologia , Luz , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/imunologia , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/imunologia , Monensin/farmacologia , Optogenética/métodos , Cultura Primária de Células , Proteína Tirosina Fosfatase não Receptora Tipo 22/deficiência , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Proteína Tirosina Fosfatase não Receptora Tipo 22/imunologia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/citologia , Linfócitos T/efeitos da radiaçãoRESUMO
Prior studies have demonstrated that immunologic dysfunction underpins severe illness in COVID-19 patients, but have lacked an in-depth analysis of the immunologic drivers of death in the most critically ill patients. We performed immunophenotyping of viral antigen-specific and unconventional T cell responses, neutralizing antibodies, and serum proteins in critically ill patients with SARS-CoV-2 infection, using influenza infection, SARS-CoV-2-convalescent health care workers, and healthy adults as controls. We identify mucosal-associated invariant T (MAIT) cell activation as an independent and significant predictor of death in COVID-19 (HR = 5.92, 95% CI = 2.49-14.1). MAIT cell activation correlates with several other mortality-associated immunologic measures including broad activation of CD8+ T cells and non-Vδ2 γδT cells, and elevated levels of cytokines and chemokines, including GM-CSF, CXCL10, CCL2, and IL-6. MAIT cell activation is also a predictor of disease severity in influenza (ECMO/death HR = 4.43, 95% CI = 1.08-18.2). Single-cell RNA-sequencing reveals a shift from focused IFNα-driven signals in COVID-19 ICU patients who survive to broad pro-inflammatory responses in fatal COVID-19 -a feature not observed in severe influenza. We conclude that fatal COVID-19 infection is driven by uncoordinated inflammatory responses that drive a hierarchy of T cell activation, elements of which can serve as prognostic indicators and potential targets for immune intervention.
Assuntos
COVID-19/imunologia , COVID-19/mortalidade , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos B/imunologia , Biomarcadores/sangue , Proteínas Sanguíneas/metabolismo , Estudos de Coortes , Estado Terminal/mortalidade , Feminino , Humanos , Imunofenotipagem , Influenza Humana/imunologia , Lectinas Tipo C/imunologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Células T Invariantes Associadas à Mucosa/imunologia , Gravidade do PacienteRESUMO
Humoral immunity requires interaction between specialized populations of B cells and CD4(+) T cells, called follicular helper T cells (T(FH) cells), in the germinal center (GC) to produce memory B cells and long-lived plasma cells. Molecular crosstalk between GC B cells and T(FH) cells influences the survival, proliferation and differentiation of each cell type. This pairing of GC B cells and T(FH) cells also occurs at the transcriptional level as the Bcl-6IRF4Blimp-1 axis, which is crucial for B cell differentiation, is also essential for the T(FH) cell identity. Less is known about the memory B cells that arise from the GC pool, as they seem to be distinctly 'programmed' on the basis of their antigen receptor affinity to enter the long-lived memory pool.
Assuntos
Linfócitos B/imunologia , Diferenciação Celular/imunologia , Centro Germinativo/imunologia , Linfócitos T/imunologia , Animais , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos B/metabolismo , Comunicação Celular/imunologia , Centro Germinativo/metabolismo , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis , Modelos Imunológicos , Plasmócitos/imunologia , Plasmócitos/metabolismo , Linfócitos T/metabolismoRESUMO
B- and T-cell acute lymphoblastic leukemia (B/T-ALL) may be refractory or recur after therapy by suppressing host anticancer immune surveillance mediated specifically by natural killer (NK) cells. We delineated the phenotypic and functional defects in NK cells from high-risk patients with B/T-ALL using mass cytometry, flow cytometry, and in silico cytometry, with the goal of further elucidating the role of NK cells in sustaining acute lymphoblastic leukemia (ALL) regression. We found that, compared with their normal counterparts, NK cells from patients with B/T-ALL are less cytotoxic but exhibit an activated signature that is characterized by high CD56, high CD69, production of activated NK cell-origin cytokines, and calcium (Ca2+) signaling. We demonstrated that defective maturation of NK cells into cytotoxic effectors prevents NK cells from ALL from lysing NK cell-sensitive targets as efficiently as do normal NK cells. Additionally, we showed that NK cells in ALL are exhausted, which is likely caused by their chronic activation. We found that increased frequencies of activated cytokine-producing NK cells are associated with increased disease severity and independently predict poor clinical outcome in patients with ALL. Our studies highlight the benefits of developing NK cell profiling as a diagnostic tool to predict clinical outcome in patients with ALL and underscore the clinical potential of allogeneic NK cell infusions to prevent ALL recurrence.
Assuntos
Células Matadoras Naturais/imunologia , Ativação Linfocitária , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígeno CD56/imunologia , Células Cultivadas , Citocinas/imunologia , Citotoxicidade Imunológica , Humanos , Lectinas Tipo C/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , PrognósticoRESUMO
The origin and developmental pathway of intestinal T cell receptor αß(+) CD4(-)CD8ß(-) intraepithelial lymphocytes (unconventional iIELs), a major population of innate-like resident cytolytic T cells, have remained elusive. By cloning and expressing several TCRs isolated from unconventional iIELs, we identified immature CD4(lo)CD8(lo)(DP(lo))CD69(hi)PD-1(hi) thymocytes as the earliest postsignaling precursors for these cells. Although these precursors displayed multiple signs of elevated TCR signaling, a sizeable fraction of them escaped deletion to selectively engage in unconventional iIEL differentiation. Conversely, TCRs cloned from DP(lo)CD69(hi)PD-1(hi) thymocytes, a population enriched in autoreactive thymocytes, selectively gave rise to unconventional iIELs upon transgenic expression. Thus, the unconventional iIEL precursor overlaps with the DP(lo) population undergoing negative selection, indicating that, concomitant with the downregulation of both CD4 and CD8 coreceptors, a balance between apoptosis and survival signals results in outcomes as divergent as clonal deletion and differentiation to the unconventional iIEL lineage.
Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Diferenciação Celular/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Animais , Antígenos CD/biossíntese , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/biossíntese , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Apoptose/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Linhagem da Célula/imunologia , Células Cultivadas , Deleção Clonal/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Lectinas Tipo C/biossíntese , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Camundongos , Camundongos Transgênicos , Receptor de Morte Celular Programada 1/biossíntese , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Transdução de Sinais/imunologiaRESUMO
The majority of genetic variants associated with common human diseases map to enhancers, non-coding elements that shape cell-type-specific transcriptional programs and responses to extracellular cues. Systematic mapping of functional enhancers and their biological contexts is required to understand the mechanisms by which variation in non-coding genetic sequences contributes to disease. Functional enhancers can be mapped by genomic sequence disruption, but this approach is limited to the subset of enhancers that are necessary in the particular cellular context being studied. We hypothesized that recruitment of a strong transcriptional activator to an enhancer would be sufficient to drive target gene expression, even if that enhancer was not currently active in the assayed cells. Here we describe a discovery platform that can identify stimulus-responsive enhancers for a target gene independent of stimulus exposure. We used tiled CRISPR activation (CRISPRa) to synthetically recruit a transcriptional activator to sites across large genomic regions (more than 100 kilobases) surrounding two key autoimmunity risk loci, CD69 and IL2RA. We identified several CRISPRa-responsive elements with chromatin features of stimulus-responsive enhancers, including an IL2RA enhancer that harbours an autoimmunity risk variant. Using engineered mouse models, we found that sequence perturbation of the disease-associated Il2ra enhancer did not entirely block Il2ra expression, but rather delayed the timing of gene activation in response to specific extracellular signals. Enhancer deletion skewed polarization of naive T cells towards a pro-inflammatory T helper (TH17) cell state and away from a regulatory T cell state. This integrated approach identifies functional enhancers and reveals how non-coding variation associated with human immune dysfunction alters context-specific gene programs.
Assuntos
Autoimunidade/genética , Sistemas CRISPR-Cas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Elementos Facilitadores Genéticos/genética , Animais , Antígenos CD/biossíntese , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/biossíntese , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Diferenciação Celular , Linhagem Celular , Cromatina/genética , Feminino , Regulação da Expressão Gênica/genética , Humanos , Subunidade alfa de Receptor de Interleucina-2/biossíntese , Subunidade alfa de Receptor de Interleucina-2/genética , Subunidade alfa de Receptor de Interleucina-2/imunologia , Lectinas Tipo C/biossíntese , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Camundongos , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Células Th17/citologia , Células Th17/imunologiaRESUMO
B cell depletion via anti-CD20 antibodies is a highly effective treatment for multiple sclerosis (MS). However, little is known about the maturation/activation stage of the returning B cell population after treatment cessation and the wider effects on other immune cells. In the present study, 15 relapsing-remitting MS patients receiving 1,000 mg of rituximab were included. B, T, and myeloid cells were analyzed before anti-CD20 administration and in different time intervals thereafter over a period of 24 mo. In comparison to the phenotype before anti-CD20 treatment, the reappearing B cell pool revealed a less mature and more activated phenotype: 1) reappearing B cells were significantly enriched in transitional (before: 10.1 ± 1.9%, after: 58.8 ± 5.2%) and mature naive phenotypes (before: 45.5 ± 3.1%, after: 25.1 ± 3.5%); 2) the frequency of memory B cells was reduced (before: 36.7 ± 3.1%, after: 8.9 ± 1.7%); and 3) reappearing B cells showed an enhanced expression of activation markers CD25 (before: 2.1 ± 0.4%, after: 9.3 ± 2.1%) and CD69 (before: 5.9 ± 1.0%, after: 21.4 ± 3.0%), and expressed significantly higher levels of costimulatory CD40 and CD86. T cells showed 1) a persistent increase in naive (CD4+: before: 11.8 ± 1.3%, after: 18.4 ± 3.4%; CD8+: before: 12.5 ± 1.4%, after: 16.5 ± 2.3%) and 2) a decrease in terminally differentiated subsets (CD4+: before: 47.3 ± 3.2%, after: 34.4 ± 3.7%; CD8+: before: 53.7 ± 2.1%, after: 49.1 ± 2.7%).