CD4 and graft versus host disease: The development of GVHD and the effects of the anti-human CD4 antibody MAX.16H5 IgG1 were compared between recipient mice receiving 1 × 107 BMCs and 3 × 107 splenocytes incubated with MAX.16H5 IgG1 (n = 5) and mice receiving a control graft, which was not incubated with the antibody (n = 5) (Figure 1).