Effects of serum complement levels on the mobilization of mature white blood cells in relation to mobilization of CFUS.

It was investigated whether the complement dependency of CFUS mobilization observed for certain mobilizing agents is unique for the CFUS compartment, or whether this mobilization reflects a more general mechanism, which involves also the mobilization of mature leukocytes. The number of all recognizable nucleated cell types in the blood was determined following the injection of the mobilizing agents, i.e. endotoxin, zymosan, cobra venom factor, proteinase, trypsin, dextran sulphate and the copolymer of polymethacrylic acid and styrene. The results indicate that if a mobilizing effect of a CFUS mobilizing agent on other nucleated cells occurs, this mobilization of nucleated cells is similarly inhibited or not by C3 to C9 depletion as is observed for the CFUS mobilization. The degree of inhibition is also comparable to the inhibition of CFUS mobilization. The significance of the complement system for the mobilization process is discussed.