Contact regulation of bone marrow mesenchymal stem cells on hepatic stellate cells

Objective To investigate the direct contact regulation of bone marrow mesenchymal stem cells (BMSCs) upon hepatic stellate cells (HSCs). Methods The co-culture system of HSC and BMSC (co-culture group) was established. After 72-h co-culture, the cells were isolated by flow cytometry. The expression levels of related receptors of Notch signaling pathway (Notch1, Notch2, Notch3 and Notch4) in HSCs and Notch-related ligands (DII1, DII3, DII4, Jag1 and Jag2) in BMSCs from the co-culture group were detected by Western blot. HSCs and BMSCs which were cultured separately were taken as the control group. The expression levels of proteins were statistically compared between two groups using t test. Results In the co-culture group, the expression level of Notch1 was 1.85±0.34, significantly higher than 0.98±0.25 in the control group (t=4.235, P<0.05). However, the expression of Notch3 was 0.40±0.12, significantly lower than 1.00±0.08 in the control group (t=-7.971, P<0.05). The expression level of Notch-related ligand Jag1 was 2.03±0.30, significantly higher compared with 0.99±0.13 in the control group (t=6.386, P<0.05). Conclusion BMSCs may regulate HSCs through combining Jag1 with Noch1 in a direct contact way. Key words: Mesenchymal stem cells; Bone marrow; Hepatic stellate cell; Coculture techniques