IL-2Rα is dispensable for murine B cell development and humoral response

The cytokine IL-2 plays a pivotal role in the immune system, specifically in the proliferation of T, B, and NK cells. The alpha subunit of the IL-2 receptor, IL-2Rα (CD25), is known to regulate the expansion and differentiation of T lymphocytes. CD25 is also expressed in developing B cells; however, its B cell intrinsic role remains undefined. We generated a mouse model with a B cell-specific deletion of CD25 to ascertain its role in B cell development and function. Unexpectedly, we found that the loss of CD25 had no impact on B cell development, homeostasis, or immune response to model antigens. Additionally, while CD25 expression was upregulated in activated splenic B cells, its absence did not affect class switch recombination in vitro or in vivo. We conclude that in contrast to its critical role in T cell differentiation and function, and despite its expression in developing and activated B cells, CD25 does not have any significant role in B cell development and adaptive immune functions.