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1.
Hepatology ; 78(3): 943-958, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36999652

RESUMO

BACKGROUND AND AIMS: HBV shapes the T-cell immune responses in HBV-related HCC. T cells can be recruited to the nidus, but limited T cells participate specifically in response to the HBV-related tumor microenvironment and HBV antigens. How epigenomic programs regulate T-cell compartments in virus-specific immune processes is unclear. APPROACH AND RESULTS: We developed Ti-ATAC-seq. 2 to map the T-cell receptor repertoire, epigenomic, and transcriptomic landscape of αß T cells at both the bulk-cell and single-cell levels in 54 patients with HCC. We deeply investigated HBV-specific T cells and HBV-related T-cell subsets that specifically responded to HBV antigens and the HBV + tumor microenvironment, respectively, characterizing their T-cell receptor clonality and specificity and performing epigenomic profiling. A shared program comprising NFKB1/2-, Proto-Oncogene, NF-KB Sub unit, NFATC2-, and NR4A1-associated unique T-cell receptor-downstream core epigenomic and transcriptomic regulome commonly regulated the differentiation of HBV-specific regulatory T-cell (Treg) cells and CD8 + exhausted T cells; this program was also selectively enriched in the HBV-related Treg-CTLA4 and CD8-exhausted T cell-thymocyte selection associated high mobility subsets and drove greater clonal expansion in HBV-related Treg-CTLA4 subset. Overall, 54% of the effector and memory HBV-specific T cells are governed by transcription factor motifs of activator protein 1, NFE2, and BACH1/2, which have been reported to be associated with prolonged patient relapse-free survival. Moreover, HBV-related tumor-infiltrating Tregs correlated with both increased viral titer and poor prognosis in patients. CONCLUSIONS: This study provides insight into the cellular and molecular basis of the epigenomic programs that regulate the differentiation and generation of HBV-related T cells from viral infection and HBV + HCC unique immune exhaustion.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Vírus da Hepatite B , Antígeno CTLA-4/metabolismo , Epigênese Genética , Recidiva Local de Neoplasia/patologia , Linfócitos T CD8-Positivos , Receptores de Antígenos de Linfócitos T/metabolismo , Microambiente Tumoral
3.
J Hepatol ; 76(1): 148-159, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34689996

RESUMO

BACKGROUND & AIMS: Regulatory T cell (Treg) depletion increases antitumor immunity. However, severe autoimmunity can occur following systemic loss of Tregs, which could be avoided by selectively depleting intratumoral Tregs. Herein, we aimed to investigate the role of tumor-infiltrating CCR4+ Tregs in hepatocellular carcinoma (HCC) and to provide a potential target strategy for immunotherapy. METHODS: CCR4+ Tregs were analyzed by flow cytometry in murine models and clinical samples. The function of tumor-infiltrating and induced CCR4+ Tregs was interrogated by genetic and epigenetic approaches. To block CCR4+ Treg chemotaxis, we developed an N-terminus recombinant protein of CCR4 (N-CCR4-Fc) as a neutralizing pseudo-receptor that effectively bound to its ligand CCL22. The efficacy of CCR4 antagonism as an immunotherapeutic agent was evaluated by tumor weights, growth kinetics and survival curves. RESULTS: CCR4+ Tregs were the predominant type of Tregs recruited to hepatitis B-associated HCC (HBV+ HCC), correlating with sorafenib resistance and HBV load titers. Compared with CCR4- Tregs, CCR4+ Tregs exhibited increased IL-10 and IL-35 expression, and enhanced functionality in suppressing CD8+ T cells. CCR4+ Tregs also displayed PD-1+TCF1+ stem-like properties. ATAC-seq data revealed substantial chromatin remodeling between tumor-infiltrating Tregs (TIL-Tregs) and induced Tregs, suggesting that long-term chromatin reprogramming accounted for the acquisition of enhanced immunosuppressive stem-like specificity by CCR4+ TIL-Tregs. Treatment with a CCR4 antagonist or N-CCR4-Fc blocked intratumoral Treg accumulation, overcame sorafenib resistance, and sensitized tumors to PD-1 checkpoint blockade. CONCLUSIONS: Intratumoral stem-like CCR4+ Tregs orchestrated immunosuppressive resource cells in the tumor microenvironment. CCR4 could be targeted to enhance antitumor immunity by specifically blocking infiltration of Tregs into the tumor microenvironment and inhibiting maintenance of the TIL-Treg pool. LAY SUMMARY: Targeting regulatory T cells is a promising approach in cancer immunotherapy; however, severe autoimmunity can occur following systemic regulatory T cell loss. This could be avoided by selectively depleting intratumoral regulatory T cells. Herein, targeting intratumoral stem-like CCR4+ regulatory T cells helped to overcome sorafenib resistance and sensitize tumors to immune checkpoint blockade in mouse models of liver cancer. This approach could have wide clinical applicability.


Assuntos
Carcinoma Hepatocelular/etiologia , Hepatite B/complicações , Hospedeiro Imunocomprometido/efeitos dos fármacos , Receptores CCR4/metabolismo , Linfócitos T Reguladores/metabolismo , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , China , Modelos Animais de Doenças , Hepatite B/imunologia , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/patogenicidade , Hospedeiro Imunocomprometido/genética , Hospedeiro Imunocomprometido/imunologia , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Camundongos , Receptores CCR4/imunologia , Linfócitos T Reguladores/imunologia
4.
Nat Cell Biol ; 23(6): 620-630, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34108657

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection often causes severe complications and even death. However, asymptomatic infection has also been reported, highlighting the difference in immune responses among individuals. Here we performed single-cell chromatin accessibility and T cell-receptor analyses of peripheral blood mononuclear cells collected from individuals convalescing from COVID-19 and healthy donors. Chromatin remodelling was observed in both innate and adaptive immune cells in the individuals convalescing from COVID-19. Compared with healthy donors, recovered individuals contained abundant TBET-enriched CD16+ and IRF1-enriched CD14+ monocytes with sequential trained and activated epigenomic states. The B-cell lineage in recovered individuals exhibited an accelerated developmental programme from immature B cells to antibody-producing plasma cells. Finally, an integrated analysis of single-cell T cell-receptor clonality with the chromatin accessibility landscape revealed the expansion of putative SARS-CoV-2-specific CD8+ T cells with epigenomic profiles that promote the differentiation of effector or memory cells. Overall, our data suggest that immune cells of individuals convalescing from COVID-19 exhibit global remodelling of the chromatin accessibility landscape, indicative of the establishment of immunological memory.


Assuntos
COVID-19/genética , Epigênese Genética , Epigenômica , Genes Codificadores dos Receptores de Linfócitos T , Memória Imunológica , Subpopulações de Linfócitos/imunologia , Monócitos/imunologia , SARS-CoV-2/imunologia , Análise de Célula Única , Imunidade Adaptativa , Adolescente , Adulto , Idoso , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/virologia , Estudos de Casos e Controles , Diferenciação Celular , Montagem e Desmontagem da Cromatina , Feminino , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Subpopulações de Linfócitos/metabolismo , Subpopulações de Linfócitos/virologia , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Monócitos/virologia , SARS-CoV-2/patogenicidade , Adulto Jovem
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