CD38 and experimental autoimmune encephalomyelitis: Interestingly, class II MHC genes, such as H2-Aa and H2-Ab1, that are known to be uniquely expressed in a subset of OPC populations identified in an experimental autoimmune encephalomyelitis mouse model (38), as well as the nonclassical MHC class I gene H2-T10, were significantly increased in O4+ cells from 2aOKO brains (Figure 5C).