Modulation of B-lymphocyte and NK cell activities by glycoinositolphospolipid purified from Trypanosoma cruzi

Glycoinositolphospholipids (GIPLs) are some of the major glycolipids of the Trypanosoma cruzi surface that were previously shown to activate B cells. In the present study, we investigated whether (i) T. cruzi GIPLs could indu ce immunoglobulin secretion from B cells in the absence of T cells and NK c ells and whether (ii) NK cells are also stimulated by the GIPLs. B cells pu rified from mice deficient in both T and NK cells (CD3 epsilon transgenic m ice) secreted immunoglobulin in response to the GIPL. This response was inc reased by coculture with a murine NK cell line. The T. cruzi GIPL also incr eased the NK cell (interleukin-2 induced) proliferative response. Our data indicate that the T. cruzi GIPL has a direct stimulatory effect on NK cells and induces immunoglobulin secretion in the absence of T lymphocytes and N K cells. These findings suggest that this T. cruzi-derived molecule may be one of the stimulators that lead to NK cell activation during T. cruzi infe ction.