Objective: To explore the method for the isolation, cultivation, and purification of adipose-derived stem cells (ADSCs) and examine the oncogenesis and homing of ADSCs to the liver in vivo.
Methods: ADSCs were isolated from female mice by digestion with 0.075% collagenase I and the morphology of the isolated cells was observed with examination of the cell surface markers and cell cycle. BALB/c mice were injected with 1×10(6) ADSCs on the back to evaluate the oncogenesis of ADSCs or with 1×10(6) ADSCs stained with 5, 6-carboxyfluorescein diacetate-succinimidyl ester (CFSE) via the tail vein to examine the cell homing to the liver.
Results: The isolated ADSCs highly expressed CD29 and CD44 and were negative for CD34, CD45, CD11b and CD14. Cell cycle distribution analysis showed cell percentages in G0/G1, S, and G2/M phases of 80.1%, 7.9%, and 12%, respectively. The ADSCs had a low immunogenicity and did not express CD40, CD80, CD86, MHCI, MHCII or PDL-1. After stimulation with IFN-γ, the expression of CD40, CD80 and PDL-1 were up-regulated slightly in the cells. Dorsal injection of the ADSCs did not result in any tumor formation within 1 month, and ADSCs injected via the tail vein showed cell homing to the liver.
Conclusion: Murine ADSCs can be isolated and expanded effectively by collagenase digestion and adherent culture. The isolated ADSCs can successfully reside in the liver after implantation, and thus may serve as a promising candidate cell in stem cell therapy of liver diseases.