| Dark areas indicate controlFig. 2Cell proliferation induced by C5a. [3H]-thymidine incorporation was measured with a liquid scintillation counter 48 h after adding the various concentrations of C5a, C5, or C3a to the HMEC-1 suspension. a C5a increased HMEC-1 proliferation in a dose-dependent manner, whereas C5 (b) and C3a (c) did not induce proliferation. d HMEC-1 was stimulated with either 10 nM C5a in the presence of various concentrations of C5a receptor antagonist W-54011 (closed column) or W-54011 alone (open column).