Immunomodulatory ability of senile mesenchymal stem cells / 中国实验血液学杂志

ABSTRACT

This study was aimed to investigate the immunomodulatory ability of human umbilical cord mesenchymal stem cells (UB-MSC) along with prolonging of culture time and increasing of passages in vitro. Mesenchymal stem cells (MSC) were isolated from human umbilical cord and cultured in vitro. The morphological changes and nucleocytoplasmic ratio of MSC were observed using Giemsa staining. MSC of the 5th passage were selected as control group, and MSC of the 13th passage were taken as senile group. The degree of cell senescence was detected by aging cells in situ test kit. Cell Counting Kit-WST-8 was used to determine the proliferation of lymphocytes in mixed lymphocytes coculture system with different passages of MSC. The expression of immunomodulation-related genes was detected by RT-PCR. The results showed that the length-breadth ratio of MSC increased and nucleocytoplasmic ratio decreased along with the increasing of passages. The senium degree of cells of the 13th passage was higher than that of the 5th passage cells. The capacity of suppressing lymphocyte proliferation of the 13th passage MSC was enhanced, compared with the 5th passage. Moreover, the expression of immunosuppression-related genes of senile MSC increased and the expression of most anti-inflammation associated genes declined as compared with young MSC by RT-PCR. It is concluded that the degree of MSC senescence gradually develops with increasing of culture passage, but the immunosuppressive ability of MSC strengthens with continuous culture.