Agly-IV.3 and recombinant effector-deficient CD32a mAbs inhibit M90 IC-induced shock. Core body temperature change in FCGR2A mice following IV injection of M90 ICs. Three hours prior to IC challenge, mice were pretreated with PBS (n = 12, solid circles) or with 1 of the following CD32a antibodies (open symbols): (A) Agly-IV.3 (n = 5); (B) cIV.3 IgG2 N297A (n = 4); (C) cAT-10 IgG1-E269R (n = 4); (D) MDE-8 IgG1-E269R (n = 3); and (E) MDE-8 IgG2-N297A (n = 2). (F) Signs of shock in control or CD32a-pretreated FCGR2A mice following M90 IC injection (same animals as panels A-E; each symbol represents 1 mouse).