ABSTRACT
Our previous work has shown that mesenchymal stem cells (MSC) have little therapeutic effect on rat arthritis induced by collagen. This study was aimed to further investigate whether the MSC lysates exhibit beneficial effects on rheumatoid arthritis. Aliquots of cell lysates from 1×10(7) human bone marrow MSC were intraperitoneally injected into collagen-induced arthritis (CIA) Wistar rats weekly for 4 consecutive weeks. Methotrexate at a dose of 1 mg/kg or normal saline was served as positive and negative controls respectively. On week 4 the symptom scores were recorded and the hind joints of the rats were pathologically examined and X-ray examination was performed. The results showed that on week 4, the symptom scores of the rats that received MSC lysates (6.87 ± 0.83) and MTX (6.44 ± 1.13) were significantly lower than that of control rats (7.33 ± 0.77, P < 0.01). Meanwhile, pathological examination on the involved ankle showed that the synovitis and arthritis scores of MSC lysates and control groups were 2.28 ± 0.48 and 2.28 ± 0.55 respectively, significantly higher than that of MTX treatment rats (0.71 ± 0.48, P < 0.05). However, X-ray examination on the ankle joints showed that the injury score of control rats was 4 ± 0.57, greatly higher than those from MSC lysates (2.71 ± 0.75) and MTX treatment groups (2.57 ± 0.78, P < 0.05 for both groups). It is concluded that MSC lysate infusion has beneficial effects on CIA rat, but the effectiveness seems inferior to MTX.
