Divergent CD4+ T-cell profiles are associated with anti-HLA alloimmunization status in platelet-transfused AML patients

IntroductionAcute myeloid leukemia (AML) is one of the commonest hematologic disorders. Due to the high frequency of disease- or treatment-related thrombocytopenia, AML requires treatment with multiple platelet transfusions, which can trigger a humoral response directed against platelets. Some, but not all, AML patients develop an anti-HLA immune response after multiple transfusions. We therefore hypothesized that different immune activation profiles might be associated with anti-HLA alloimmunization status.MethodsWe tested this hypothesis, by analyzing CD4+ T lymphocyte (TL) subsets and their immune control molecules in flow cytometry and single-cell multi-omics.ResultsA comparison of immunological status between anti-HLA alloimmunized and non-alloimmunized AML patients identified differences in the phenotype and function of CD4+ TLs. CD4+ TLs from alloimmunized patients displayed features of immune activation, with higher levels of CD40 and OX40 than the cells of healthy donors. However, the most notable differences were observed in non-alloimmunized patients. These patients had lower levels of CD40 and OX40 than alloimmunized patients and higher levels of PD1. Moreover, the Treg compartment of non-alloimmunized patients was larger and more functional than that in alloimmunized patients. These results were supported by a multi-omics analysis of immune response molecules in conventional CD4+ TLs, Tfh circulating cells, and Tregs.DiscussionOur results thus reveal divergent CD4+ TL characteristics correlated with anti-HLA alloimmunization status in transfused AML patients. These differences, characterizing CD4+ TLs independently of any specific antigen, should be taken into account when considering the immune responses of patients to infections, vaccinations, or transplantations

ZO-1 Intracellular Localization Organizes Immune Response in Non-Small Cell Lung Cancer

International audienceDelocalization of zonula occludens-1 (ZO-1) from tight junctions plays a substantial role in epithelial cell plasticity observed during tumor progression. In vitro , we reported an impact of ZO-1 cyto-nuclear content in modulating the secretion of several pro-inflammatory chemokines. In vivo , we demonstrated that it promotes the recruitment of immune cells in mouse ear sponge assays. Examining lung cancers, we showed that a high density of CD8 cytotoxic T cells and Foxp3 immunosuppressive regulatory T cells in the tumor microenvironment correlated with a cyto-nuclear expression of ZO-1. Taken together, our results support that, by affecting tumor cell secretome, the cyto-nuclear ZO-1 pool may recruit immune cells, which could be permissive for tumor progression

Involvement of zonula occludens-1 in pro-inflammatory processes associated to metastatic progression of lung cancers

Zonula occludens 1 (ZO-1) est une protéine sous-membranaire des jonctions serrées impliquée dans l’organisation structurale des cellules épithéliales. Au cours de la progression tumorale, associée au processus de transition épithélio-mésenchymateuse (TEM), les composants des jonctions intercellulaires sont réorganisés. Notamment, lors de la TEM, la protéine ZO-1 est délocalisée de la membrane vers le cytoplasme et/ou le noyau où elle adopte alors un rôle pro-invasif. Nous avons d’ailleurs montré que ZO-1 cyto-nucléaire régule l’expression de la chimiokine IL-8 dans les cancers broncho-pulmonaires non à petites cellules (CBNPC). Nous nous sommes donc intéressés à l’influence de ZO-1 cyto-nucléaire sur le recrutement des cellules inflammatoires dans les CBNPC. In vitro, le niveau d’expression de ZO-1 module le recrutement de la lignée monocytaire THP-1. Par différentes techniques in vivo, nous avons montré que la surexpression de ZO-1 cyto-nucléaire favorise le recrutement de cellules inflammatoires et immunitaires à des temps précoce et tardif de la réponse immunitaire. En parallèle, la caractérisation de l’infiltrat inflammatoire en fonction de la localisation nucléaire de ZO-1 chez les patients atteints de CBNPC a mis en évidence une corrélation entre l’expression cyto-nucléaire de ZO-1 et la présence de lymphocytes T cytotoxiques CD8+ au sein du microenvironnement tumoral.Ainsi, notre étude révèle un nouveau rôle de la protéine structurale ZO-1. En effet, ZO-1 cyto-nucléaire, associé au processus de TEM, est impliqué dans la mise en place et le développement d’un microenvironnement pro-inflammatoire et/ou pro-immunitairepermissif pour la progression tumorale des CBNPC.Zonula occludens 1 (ZO-1) is a sub-membrane protein of tight junctions involved in the structural organization of epithelial cells. During tumor progression, associated with the epithelial-mesenchymal transition (EMT) process, intercellular junction components are reorganized. In particular, during EMT, ZO-1 protein is delocalized from the membrane to the cytoplasm and/or the nucleus where it then displays pro-invasive properties. We have shown that ZO-1 cyto-nuclear regulates the expression of chemokine IL-8 in non-small cell lung cancer (NSCLC). We are therefore interested in the influence of cyto-nuclear ZO-1 on the recruitment of inflammatory cells in NSCLC. In vitro, the level of expression of ZO-1 modulates the recruitment of the monocyte-like cell line THP-1. By different in vivo techniques, we have shown that overexpression of cyto-nuclear ZO-1 promotes the recruitment of inflammatory and immune cells at early and late times of the immune response. In parallel, the characterization of the inflammatory infiltrate as a function of the nuclear localization of ZO-1in patients with NSCLC revealed a correlation between the cyto-nuclear expression of ZO-1 and the presence of cytotoxic T lymphocytes CD8+ within the tumor microenvironment.Thus, our study reveals a new role of structural protein ZO-1. Indeed, ZO-1 cyto-nuclear, associated with the EMT process, is involved in the establishment and development of a proinflammatory and/or pro-immune microenvironment permissive for tumor progression of NSCLC

Divergent CD4+ T-cell profiles are associated with anti-HLA alloimmunization status in platelet-transfused AML patients

International audienceIntroduction Acute myeloid leukemia (AML) is one of the commonest hematologic disorders. Due to the high frequency of disease- or treatment-related thrombocytopenia, AML requires treatment with multiple platelet transfusions, which can trigger a humoral response directed against platelets. Some, but not all, AML patients develop an anti-HLA immune response after multiple transfusions. We therefore hypothesized that different immune activation profiles might be associated with anti-HLA alloimmunization status. Methods We tested this hypothesis, by analyzing CD4+ T lymphocyte (TL) subsets and their immune control molecules in flow cytometry and single-cell multi-omics. Results A comparison of immunological status between anti-HLA alloimmunized and non-alloimmunized AML patients identified differences in the phenotype and function of CD4+ TLs. CD4+ TLs from alloimmunized patients displayed features of immune activation, with higher levels of CD40 and OX40 than the cells of healthy donors. However, the most notable differences were observed in non-alloimmunized patients. These patients had lower levels of CD40 and OX40 than alloimmunized patients and higher levels of PD1. Moreover, the Treg compartment of non-alloimmunized patients was larger and more functional than that in alloimmunized patients. These results were supported by a multi-omics analysis of immune response molecules in conventional CD4+ TLs, Tfh circulating cells, and Tregs. Discussion Our results thus reveal divergent CD4+ TL characteristics correlated with anti-HLA alloimmunization status in transfused AML patients. These differences, characterizing CD4+ TLs independently of any specific antigen, should be taken into account when considering the immune responses of patients to infections, vaccinations, or transplantations