Human infection with Onchocerca volvulus does not affect the T helper cell phenotype of the cellular immune response to mycobacterial antigen.

In order to determine whether infection with Onchocerca volvulus might modify the immune response to mycobacterial antigen, the proliferative and cytokine responses of peripheral blood mononuclear cells from 117 persons infected with O. volvulus and 36 non-endemic control subjects were compared. Tuberculin-stimulated cellular proliferative responses and production of Th1-type cytokines (interferon gamma) were reduced in persons infected with O. volvulus compared to controls. However, there was no evidence of polarization of the immune response towards a Th2-type phenotype (interleukin 5) in infected individuals compared to controls.