[0063] The primary Fc dependent functions of an antibody for target cell elimination are complement dependent cytotoxicity (CDC) initiated by binding Clq to the Fc region; antibody dependent cytotoxicity (ADCC) mediated by the interaction of the Fc region with Fcy receptors (FcyRs), primary FcyRIIIa on immune effector cells (e.g., NK cells and
Neutrophils); and antibody dependent cellular phagocytosis (ADCP) which is carried out by มาโครฟาจ through the recognition of opsinized target cells via FcyRI. Antibody
subclasses have differences in their abilities to mediate Fc-dependent effector activities. In humans, the IgG1 and IgG3 subclasses have high potency for CDC due to binding Clq. In addition, the IgG1 subclass has the highest แอฟฟินิตี้ for FcyRs and is thereby the most potent in terms of ADCC and Fc-dependent ADCP. The IgG4 subclass is devoid of Clq binding ability and has greatly reduced FcyR แอฟฟินิตี้ยึดเกาะ and thereby has significantly
diminished effector function.