Effect Of Mycobacterium Phlei F.U.36 On The Culture And Proliferation Of Dendritic Cells Derived From Human Umbilical Cord Blood In Vitro

Objective To investigate the effect of Mycobacterium phlei F.U.36 suspended liquor(Utilin"s" , U) on the culture and proliferation of dendritic cells (DC) derived fromhuman umbilical cord blood in vitro.Methods The mononuclear cells were isolated from human umbilical cord blood andcultured with RPMI-1640 in the control group,while the test groups were cultured withU + RPMI-1640, rhGM-CSF+ rhTNF-a+ rhIL-4+ RPMI-1640(GTI), GTI+ U +RPMI-1640(GTIU) respectively. The growth of DC was observed under a lightmicroscope.We determined the phenotypes of DC by flow cytometry on the 10th day ofculture,and dyed some harvest cells with Wright-Giemsa,then observed andphotographed them under an oil microscope.Results The test groups all attained some number of typical DC;Both CD1a positivecell rate and HLA-DR positive cell rate of the U group were higher than those of thecontrol; HLA-DR positive cell rate of the GTIU group increased mostsignificantly, much higher than that of the GTI group.Conclusion Mycobacterium phlei F.U.36 suspended liquor not only promotes theproliferation of DC derived from human umbilical cord blood in vitro,but alsoco-operates with rhGM-CSF, rhTNF-a and rhIL-4 in promoting the maturity of DC. Objective To investigate the effect of mycobacterium phlei F.U.36 suspended liquor on theanti-leukemia immune effect induced by dendritic cells derived from human umbilical cordblood.Methods The mononuclear cells were isolated from human umbilical cord blood and culturedwith RPMI-1640 + rhGM-CSF+ rhIL-4 +rhTNF-a in the control group.Moreover, we putHL-60 complete cell antigen into the control group on the 4th and 9th day of culture. The testgroups were cultured with the same cytokines and antigen as the control group.Besides,on the7th day,we put different quantity of mycobacterium phlei F.U.36 suspended liquor into everytest groups and kept its effect for different time respectively. The growth of DC was observedunder a light microscope. We determined the phenotypes of DC by flow cytometry on the12th day of culture,then mixed DC with T lymphocytes derived from paracmastic childs whosuffered from acute myeloblastic leukemia to induce antigen specific cytotoxic Tcells.Cytotoxicity assay was measured by MTT method.Results The concentration and action time of mycobacterium phlei F.U.36 suspended liquorboth had no effect on CD1a positive cell rate.But the concentration and action time ofmycobacterium phlei F.U.36 suspended liquor had an effect on HLA-DR positive cell rateand the cytotoxicity,HLA-DR positive cell rate and the cytotoxicity of the test groups werehigher than those of the control group.Within a certain scope, along with the increase ofmycobacterium phlei's concentration and action time, HLA-DR positive cell rate and thecytotoxicity increased accordingly.Conclusion Mycobacterium phlei F.U.36 suspended liquor may promote the maturity of DCand boost the ability of DC in angtigen presentation, thus, it can enhance the anti-leukemiaimmune effect induced by dendritic cells derived from human umbilical cord blood.