The Protection And Remediation Effects Of Local Transplantation Of BMMSCs In Rheumatoid Arthirtis-induced Cartilage Injury

Background: Patients with rheumatoid arthritis (RA) are always companied with articularsynovial hyperplasia and different degrees of cartilage destruction. Recently, Bone marrowmesenchymal stem cells (BMMSCs) have attracted more and more attention. Apart from thechondrogenic capacity, it also exhibit immunosuppressive property, which have beeninvestigated in the treatment of various autoimmune diseases. While, previous researchesmainly focused on intravenous or intraperitoneal injection of BMMSCs to observe the effecton systemic immunosuppression. Poor inhibitory efficiency on articular inflammatoryreaction and inferior result of preventing persistent destruction of cartilage were observed.Objective: Toward the classical type II collagen-induced arthritis in rats, the combinationtreatment of microfracture and in situ transplantation of thermogel-encapsulated BMMSCswere performed to observe the cartilage protection. Furthermore, the ovalbumin-inducedarthritis in rabbit was applied and in situ transplantation of fibrin gel-encapsulated BMMSCsin osteochondral defects were performed to evaluate the remediation effects on full-thicknesscartilage defect.Results: In the model of ovalbumin-induced arthritis, the results confirmed that BMMSCsobviously down-regulated the ratio of CD4+to CD8+T lymphocytes in peripheral blood. Inaddition, it resulted in the decreased levels of inflammatory cytokines, such as interleukin-1β,tumor necrosis factor-α and anti-collagen type II antibody, in the serum. Simultaneously, thecombination therapy also could inhibit the proliferation of antigen specific lymphocytes andlocal joint inflammatory condition, and prevent the articular cartilage damage. The resultsindicated that the treatment programs could effectively stimulate BMMSCs to exhibit theimmunosuppression and cartilage protection capability. On the other hand, in the model ofovalbumin-induced arthritis, in situ transplantation of fibrin gel-encapsulated BMMSCs inosteochondral defects performed outstanding capacity of cartilage repair, and resulted inremission of local joint inflammatory condition and prevented the articular cartilage damage.Conclusion: The results demonstrated that BMMSCs transplantation in osteochondraldefects under arthritic condition could effectively stimulate BMMSCs to exhibit theimmunosuppression and cartilage protection capability, as well as cartilage repair. This study provided a new therapeutic strategy for RA via local transplantation.