Lesional senescent CD4⁺ T cells mediate bystander cytolysis and contribute to the skin pathology of human cutaneous leishmaniasis.

ABSTRACT: Cytotoxic activity is a hallmark of the immunopathogenesis in human cutaneous leishmaniasis (CL). In this study, we identified accumulation of CD4⁺ granzyme B producing T cells with increased cytotoxic capacity in CL lesions. These cells showed enhanced expression of activating NK receptors (NKG2D and NKG2C), diminished expression of inhibitory NKG2A, along with the upregulation of the senescence marker CD57. Notably, CD4⁺ T cells freshly isolated from CL lesions demonstrated remarkable capacity to mediate NL-like bystander cytolysis. Phenotypic analyses revealed that lesional CD4⁺ T cells are mainly composed of late-differentiated effector (CD27-CD45RA-) and terminally differentiated (senescent) TEMRA (CD27-CD45RA+) subsets. Interestingly, the TEMRA CD4

SUBMITTER: Covre LP 

PROVIDER: S-EPMC11532160 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature