Gelsolin-actin complex is target for ADP-ribosylation by Clostridium botulinum C2 toxin in intact human neutrophils

The gelsolin-actin complex was ADP-ribosylated by Clostridium botulinum C2 toxin and Clostridium perfringens iota toxin in lysates of human platelets and human neutrophils. When [32P]orthophosphate-labelled human neutrophils were treated with C. botulinum C2 toxin, [32P]ADP-ribosylated gelsolin-actin was precipitated with anti-gelsolin antibody. Stimulation of neutrophils by formyl-methionine-leucine-phenylalanine decreased the interaction of gelsolin with ADP-ribosylated actin in toxin-treated cells. The data indicate that the gelsolin-actin complex is a pathophysiological substrate for actin-ADP-ribosylating toxins