PTPRC and rheumatoid arthritis: MANF was expressed in 23 biopsies (9/9 OA, 7/7 CPPA and 7/8 (87%) RA), PTPRC in 23 biopsies (9/9 OA, 6/7 (86%) CPPA and 8/8 RA), EML4 in 20 biopsies (8/9 (89%) OA, 5/7 (71%) CPPA and 7/8 (87%) RA).