CD40LG and Absence of circulating granulocytes: The existence of complement-dependent IgM antibodies against granulocytes in the serum of a patient who was receiving ATDs and suddenly developed agranulocytosis was reported, but antibody-mediated cytotoxicity was evident only against granulocytes taken from 2 of the 8 donors, suggesting that only a subset of patients receiving ATD may be susceptible to agranulocytosis [17].