Semaphorin Sema4D in the regulation of TFH-like cells

The role of endogenous semaphorin Sema4D in the control of circulating follicular T helper cells (CD4 CXCR5 Т lymphocytes) has been studied. The involving of Sema4D in functional molecule PD-1 expression increasing, as well as in T-dependent B lymphocyte differentiation in T-/B-coculture in response to polyclonal T lymphocyte activation was shown. The data demonstrate a possible new mechanism of Sema4D-dependent regulation of the humoral immune response, implying the direct semaphorin participation in B-lymphocyte differentiation, supported by follicular helper T cells.