In vivo effect of the mAbs.

Mice received 100 μg purified mAb intravenously in 200 μL sterile PBS. (A) Platelet counts were determined at the indicated times, using an improved Neubauer hemocytometer. Injection of a nonimmune IgG1 had no significant effect on the platelet count (not shown). Results are shown as mean ± SD for groups of 6 mice each (○: IgG1; ■: IgG2a; ▿: IgG2b). (B) Hematocrits were determined at the indicated times.