The Effect Of Lysates Of Intestinal Bacteria On Human Umbilical Cord-derived Mesenchymal Stem Cells And Its Innate Immune Receptors Expression

AIM:Study the effect of the lysates of intestinal bacteria on the proliferation and differentiation in human umbilical cord-derived mesenchymal stem cells and its innate immune receptors. In order to accumulate experimental data and provide theoretical basis about the intestinal microflora regulation to improve body function and treat relative diseases in clinical practice.METHODS: Through the intestinal microflora specificity selective culture medium to separate and prepare lysates of coli bacillus, enterococcus, lactobacillus, bacillus bifidus, fecal flora; various lysates(6.6%) were separately added to the culture system of P3 h UC-MSCs, LPS and sample solution as control. After continuous culture one week, P3 h UC-MSCs were induce to osteogenesis and adipogenesis; TLRs and NLRs m RNA and their proteins were analyzed by RT-q PCR and Western Blotting.RESΜLTS: Various cultural intestinal bacteria have the morphology and biochemical characteristics of colibacillus, enterococcus, lactobacillus, and bacillus bifidus, respectively. The isolated cell have phenotype of CD29+/CD44+/CD105+/CD31-/CD34-/CD40-/CD45-/CD106-/HLA-DRand the ability of osteogenesis and adipogenesis, and them are h UC-MSCs. The h UC-MSCs cultivate in the lysates of lactobacillus has a faster proliferation and increase its ability of osteogenesis and adipogenesis,and decrease the gene expression of TLR2/4(P<0.05)and its protein expression.;however,h UC-MSCs cultivate in the lysates of colibacillus has a lower proliferation and decrease its ability of osteogenesis and adipogenesis,and increase the gene expression of TLR2/4(P<0.05) and its protein expression. Totality,every experimental intestinal bacteria group has divers effect on the gene expression of TLRs and NLRs in h UC-MSCs(P>0.05).CONCLUSION: The experimental results suggest that the active components in lysates of lactobacillus can inhibit TLR2/4 signal passage in h UC-MSCs, and activate its proliferation and differentiation; however, active components in lysates of colibacillus can activate TLR2/4 signal passage in h UC-MSCs, and inhibit its proliferation and differentiation. There are great varieties of known intestinal bacteria, and their lysates of bioactive components are complex and different.Their impact on h UC-MSCs and its mechanism remains to be discussed.