FCGR1A and chlamydia trachomatis infectious disease: The role of IgG‐opsonization on antigen presentation on chlamydial infection of antigen‐presenting cells is less well elucidated, but mouse macrophages with functional FcγRI (CD64), FcγRIIB1 (CD32) and FcγRIII (CD16) have enhanced antibody‐dependent cellular cytotoxicity (ADCC) killing of infected cells and enhance Th1 responses in vitro, compared to FcγR‐deficient macrophages and antibody controls.45