Impact of monogenic mutations on differentiation of human naive CD4⁺ T cells. Pathways of human naive CD4⁺ T cell differentiation in vitro and how specific mutations compromise these processes. MSMD, Mendelian susceptibility to mycobacterial disease; IBD, inflammatory bowel disease. The corresponding diseases listed occur in individuals with gene mutations that are shown in red type. The genes shown in black type do not result in the indicated disease states.