Abstract: Objective： To explored whether adipose derived stem cells (ASCs) could inhibit the pro-liferation of peripheral blood mononuclear cells (PBMCs) and whether inflammatory priming could enhance this property of ASCs. Methods: We isolated ASCs using collagenase from adipose tissue and expanded them in vitro. Cells were induced to differentiate into adipogenic and osteogenic lineages. The cells at passage 3 to passage 5 were used for the experiments. After carboxy fluoresce in succinimidyl ester (CFSE) staining, PBMCs were co-cultured with inflammatory priming ASCs. The PBMCs cultured without ASCs or with nontreated ASCs defined as control groups. Then we used flow cytometry to detect the proliferation of PBMCs. Results: ASCs had fibroblast-like phenotype and were spindle shaped. They were able to differentiate into cells of adipogenic and osteogenic lineages in specific induction media. ASCs had the CD expression profile consistant with the International Federation for Adipose Therapeutics statement. The percentage of parent cells in PBMC after co-cultured with ASCs increased, though there was no statistical significance. However, when co-cultured with inflammatory priming ASCs, the percentage of parent cells significantly increased (with inflammatory priming ASCs group vs. without ASCs group, 38.7%±10.0% vs. 28.4%±8.9%, P<0.05). This indicated that inflammatory priming ASCs could significantly inhibit the proliferation of PBMCs. Conclusion: Inflammatory cytokines can enhance the immunosuppressive ability of ASCs. Our findings may help the application of ASCs in tissue repairment with better results.

Key words: Adipose tissue, Stem cells, Tissue engineering, Leukocytes, mononuclear, Cell proliferation