Abstract
BACKGROUND: Mesenchymal stem cells (MSCs) enhance tissue repair through paracrine effects following transplantation. The versican protein is one of the important factors contributing to this repair mechanism. Using MSC conditioned medium for cultivating monocytes may increase versican protein production and could be a good alternative for transplantation of MSCs. This study investigates the effect of culture medium conditioned by human MSCs on the expression of the versican gene in peripheral blood mononuclear cells (PBMCs) under hypoxia-mimetic and normoxic conditions. METHODS: The conditioned media used were derived from either adipose tissue or from Wharton’s jelly (WJ). Flow cytometry for surface markers (CD105, CD73, and CD90) was used to confirm MSCs. The PBMCs were isolated and cultured with the culture media of the MSC derived from either the adipose tissue or WJ. Desferrioxamine and cobalt chloride (200 and 300 µM final concentrations, respectively) were added to monocytes media to induce hypoxia-mimetic conditions. Western blotting was applied to detect HIF-1α protein and confirm hypoxia-mimetic conditions in PBMC. Versican gene expression was assessed in PBMC using RT-PCR. Western blotting showed that the expression of HIF-1α in PBMC increased significantly (p < 0.01). RESULTS: RT-PCR results demonstrated that the expression of the versican and VEGF genes in PBMC increased significantly (p < 0.01) in hypoxia-mimetic conditions as compared to normoxia. CONCLUSION: Based on the findings in the present study, the secreted factors of MSCs can be replaced by direct use of MSCs to improve damaged tissues.