• The present study investigated the effect of coagulation on neutrophil complement receptors (CRs) 1 and 3, which are specific for the opsonins C3b and C3bi. Incubation of neutrophils in autologous serum, but not in plasma, increased the mean (±SD) expression of CR1 (×3.43±0.93) and CR3 (×3.07 ±0.86), in comparison with incubation in buffer. Serum also increased neutrophil superoxide production in response to opsonized zymosan from 0.48±0.21 to 1.05±0.25 nmol/106 cells/min. Similarly, calcium conversion of platelet-rich plasma (but not platelet-poor plasma) to serum also increased both CR1 and CR3 expression. This finding, as well as the fact that freeze-thawed platelet-rich plasma (but not platelet-poor plasma) increased CR expression, indicated that platelet constituents were the origin of this CR-inducing activity. Other nonplatelet factors formed during coagulation, such as C5a, fibrinogen degradation products, kallikrein, and factor Xlla, were shown not to be responsible for this CR-inducing activity.
(Arch Surg 1988;123:199-203)