Immunomodulatory properties of umbilical cord vein mesenchymal stromal cells influenced by gestational age and in vitro expansion

In vivo and in vitro aging of the mesenchymal stromal cells (MSCs) can affects their properties. We investigated the immunomodulatory properties of the term and preterm human umbilical cord vein MSCs (UCV-MSCs) at the passages (P) 2 and 5. Term and preterm UCV-MSCs at P2 and 5 were co-cultured with two-way mixed lymphocyte reaction. Proliferation, IFN-γ and IL-10 protein levels, mRNA levels of the COX-2, TGF-β1, TNF-α, IL-4 and FoxP3 were assessed. The term UCV-MSCs and P5 of the term and preterm UCV-MSCs had stronger inhibitory effects on cell proliferation than the preterm UCV-MSC and P2, respectively (P = 0.001). In supernatants of the co-cultures, IFN-γ was higher in the term UCV-MSC than the preterm UCV-MSC, while IL-10 was higher in the preterm UCV-MSCs than the term UCV-MSCs. Also in the co-cultures, COX-2 expression in the term UCV-MSCs and P2 was higher than the preterm UCV-MSCs and P5, respectively and TGF-β1 expression in the term UCV-MSCs was higher than preterm. Conclusively it appears that the term UCV-MSCs, and P5 of the term and preterm UCV-MSCs showed a higher immunomodulatory ability than the preterm UCV-MSCs and P2, respectively.