conjugates of b cells and platelet microparticles in the human peripheral blood

background: activated platelets shed microparticles (mps) in vivo and certainly in vitro under storage. like platelets, platelet-derived mps contribute to hemostatic and inflammatory responses. we sought to determine the interactions between platelet mps and peripheral b lymphocytes in the healthy blood circulation to propose a possible role for platelet mps in the functioning of b cells.   materials and methods: an enzyme-linked immunosorbent assay (elisa) was established to determine the normal interactions between human peripheral blood b lymphocytes and platelet mps. b cells were isolated and bound to the wells of microtiter plates using coated anti-cd19. then the presence of attached mps was surveyed. also, platelet mps were separated from human platelet concentrates and applied to confirm the new binding capacities of b cells for these microvesicles. results: platelet mps were recognized in the wells of elisa in which only b cells were isolated. so mps were bound with peripheral blood b cells. furthermore, using this method, the role of cd40/ cd40l interaction was displayed for the binding. conclusion: it seemed that the binding of platelet mps to b cells normally took place in vivo and a percent of b cells circulate in blood in connection with platelet mps. k e y w o r ds: elisa, platelet microparticles (platelet mps), b cells, cd40l