CD8A and graft versus host disease: In a murine model, it was found that GVHD may be inhibited by preventing CD8+ CTL migration into the Peyer’s patch either by disrupting the gene encoding the CCR5 chemokine receptor or by blocking the integrin α4β7-mucosal vascular addressin (MAdCAM-1) interaction into the gut Peyer’s patches (Murai et al., 2003).