Effect of erythrocyte-reactive monoclonal antibodies on the number of circulating erythrocytes.

Fifty μg of the indicated monoclonal antibody or 50 mg IVIG (■) was administered intravenously 24 hours prior to injection of antiplatelet antibody. Twenty-four hours later, blood was sampled and the erythrocyte count was assessed by flow cytometry. (A) Anti–TER-119; (B) anti-CD24 (IgG_2b); (C) anti-CD24 (IgG_2c). The data are presented as fold change over the untreated group. The hatched rectangle indicates the range of the mean fold change of erythrocytes (± 1 SEM) of mice treated with antiplatelet antibody only; n = 9 for each data point. *P < .05; **P < .01; ***P < .001 as compared with ITP mice. Error bars indicate SEM.