C3 and influenza: We found that influenza proliferation was inhibited in a dose-dependent manner by treating MDCK cells with the following: BAPTA-AM (an intracellular calcium chelator) or verapamil (a calcium-channel blocker), C3 exoenzyme (inhibits RhoA); trifluoperazin dimaleate (inhibits calmodulin); bisindolylmaleimide I (inhibits PKC); U0126 and PD98059 (inhibit MEK/ERK); GW 5074 (inhibits Raf-1); or cytochalasin D (inhibits actin polymerization) (table 1, data not shown).