Adoptive transfer of CD4+ T cells from C57BL/6 donor mice into C57BL/6 recipient mice, or into p40ko mice resulted in EAE (Fig 4A), indicating that p40 expression in the CNS is not an absolute requirement for CNS autoimmunity to occur once antigen-specific peripheral CD4+ T cells are activated and differentiated. Here, CD4 is linked to Autoimmunity.