Faecalibacterium Prausnilzii Genomic DNA Enhances The Killing Activity Of Human Peripheral Blood Mononuclear Cells To Lovo Cells By Upregulating Th1 Immune Response

Background and Aims:intestinal bacteria and their genomic DNA involved i n a variety of immune regulation,but there are differences in their function,th e aim of this study were to investigate the killing activity of Faecalibacterium prausnilzii(F.prausnilzii)and F.prausnilzii genomic DNA(fDNA)intervent the peripheral blood mononuclear cells(PBMCs)to lovo cancer cell and the effe cts of IFN-? and IL-4 concentration and Th1,Th2 cell type-specific nuclear tra nscription factor T-bet,GATA3 mRNA expression in PBMCs cells,and investig ate the immunological mechanisms in F.prausnilzii DNA treat colorectal cancer.Methods:PBMCs are co-cultured in vitro with F.prausnilzii,fDNA,the digestive F.prausnilzii genomic DNA(d-fDNA).respectively,Killing activity of interventio n groups against lovo cells is measured by MTT,the IFN-? and IL-4 concentr ation in PBMCs cultured supernatant are measured by ELISA.The expressions of Th1 and Th2 specific transcription factor T-bet and GATA3 mRNA are me asured by qRT-PCR.Results:Compared with non-intervention group(26.5±6.717)%,fDNA group(49.43±6.774)%on lovo cytotoxic activity was significantly increased(P<0.05);F.pra usnilziigroup(35.73±1.967)%,and d-fDNA group(28.80±5.455)%,compared with PBMCs group,are not statistical significance(P>0.05);compared secretion of IF N-y in fDNA group(529.4±36.29)pg/mL with the other three groups:F.prausnilzii group(288.6±31.01)pg/mL,d-fDNA group(220.3±20.72)pg/mL,control group(203.2±23.61)pg/mL are significantly increased(P<0.001);compared secretion of IL-4 in fDNA group(14.35±2.10)pg/mL with the d-fDNA group(29.57±4.92)pg/m L and the control group(30.91 ±3.35)pg/mL are statistically significant(P<0.05);T-bet mRNA expression level in fDNA group(1.699±0.082)is significantly hi gher than that in d-fDNA group(1.066±0.201)and control group(P<0.05),GAT A3 mRNA expression level in fDNA group(0.511±0.077)is lower than d-fDN A group(1.066±0.101)and control group(P<0.05).T-bet mRNA(1.144±0.204)and GATA3 mRNA(0.799±0.143)expression level in F.prausnilzii group compared with the control group were not statistically significant(P>0.05).Conclusions:fDNA have significant anti-tumor effect;the mechanism may be associated with increased the PBMCs IFN-y secretion and mRNA expression of nuclear transcription factor T-bet,raised the Th1 immune response.