Neutrophils are necessary for hFcγRI-dependent ASA. Mice were immunized with BSA in Freund adjuvant and challenged with BSA and their central temperatures and survival rates were monitored. (A-B) ASA in hFcγRI^tg 5KO and/or 5KO mice injected with indicated reagents (n = 5). (C-F) ASA in anti-FcγRIV–treated hFcγRI^tg 5KO mice injected with indicated reagents (C, n ≥ 4; D, n = 5; E, n = 5; F, n ≥ 3). Data are representative from at least 2 independent experiments and are represented as means ± SEM. Cld2 lipo indicates toxic liposomes; GdCl2, gadolinium; and Cypro, cyproheptadine.