PPIB and chronic inflammatory demyelinating polyradiculoneuropathy: In CIDP, studies suggest a role for CD8 cells, that interact with MHC class I. A recent study found that HLA-associated shaping of T cell receptor B variable (TCRBV) usage in CD8+ T cells differed between the sexes, with male cells showing greater expansion of TCRBV usage than females (297); this is evidence that there could be sex differences in the capacity of these cells to interact with self antigens.