In vivo experiments showed that TXNDC5-Tg mice are susceptible to collagen-induced arthritis (CIA); In vitro experiments showed that increased TXNDC5 expression in Rheumatoid arthritis synovial fibroblast-like cells (RASFs) could promote cell invasion, migration and secretion of TNF-α, IL-1α, IL-1β and IL-17. Here, TXNDC5 is linked to rheumatoid arthritis.