To examine if there was a close relationship between the ability of selected CD44 antibodies to ameliorate inflammatory arthritis and induce thrombocytopenia at relevant doses, the antibodies IM7, KM201, KM114, KM81, 5035-41.1D,IRAWB14.4, and control IgG were examined at doses and regimes similar to those used in other murine arthritis models [12], [13], [14]. This evidence concerns the gene CD44 and Thrombocytopenia.