IL15 and rheumatoid arthritis: Certainly, PC chemically conjugated to ovalbumin (PC-OVA) or BSA (PC-BSA), but not recombinant ES-62 (which lacks PC), mimics ES-62’s ability to protect against TH1/TH17 autoimmune responses and development of CIA [52, 53], as well as its in vitro inhibition of IFNγ production from cytokine (IL-12 and IL-15/IL-18)-stimulated synovial membrane cultures derived from RA patients [52].