Blimp‐1 is expressed in human and mouse T cell subsets and leads to loss of IL‐2 production and to defective proliferation

Publisher Website
Google Scholar
Abstract
The transcriptional repressor Blimp‐1 regulates terminal differentiation of B‐lymphocytes and myeloid cells. We now show that Blimp‐1 is also expressed in human and murine primary T lymphocytes. Blimp‐1 expression is highest in freshly isolated primary T cells with an antigen experienced phenotype. Th2 and CD4+CD25+ cells exhibited higher levels of Blimp‐1 mRNA than Th1 cells. However, ectopic expression of Blimp‐1 by retroviral transduction neither altered the frequency of IFN‐γ or IL‐4 producing cells nor did it induce suppressor activity. In non‐polarized cells, retroviral transduction of Blimp‐1 led to a marked reduction in IL‐2 secretion, to an inability to proliferate and to reduced viability. Our data suggest that Blimp‐1 is physiologically expressed in T lymphocytes during late stages of differentiation, induces down regulation of IL‐2 production and a shortened life span and might thus contribute to a limitation of T cell immune responses.