1.Silencing gene of TLR4 down-regulates the effect of TLR2 signal transduction in RAW264.7 cells to anti-Aspergillus fumigatus conidia stimulation
Zhenhua RAO ; Genhua ZHU ; Weihua XIE ; Mingsheng SU ; Kai LONG ; Hongdan LUO ; Xiaomei XIE
Chinese Journal of Microbiology and Immunology 2012;32(2):108-113
Objective To study the role of TLR2 and TLR4 signal transduction in RAW264.7 monocyte-macrophages stimulated by Aspergillus fumigatus conidia,and to investigate the expression of TLR2 signal transduction after silencing gene of TLR4.Methods Macrophages were randomly divided into normal group ( N group),normal+stimulated with Aspergillus fumigatus conidia ( N +Af group ),normal + transfected with TLR4-siRNA [ TLR4 (RNAi) group ],normal+transfected with TLR4-siRNA +stimulated with Aspergillus fumigatus conidia[ TLR4(RNAi) +Af group].RT-PCR and Western blot were used to assay expression levels of TLR2,TLR4,MyD88 mRNA and pro-inflammatory cytokines TNF-α protein when macrophages were stimulated 12 h by Aspergillus fumigatus conidia after tranfected 24 h with TLR4-siRNA by technology of RNAi.Results ( 1 ) Compared with N group,the expression of TLR2,TLR4,MyD88 mRNA and TNF-αprotein in N+Af group significantly increased before silencing gene of TLR4.(2) Silencing efficiency of macrophates was up to 83% after transfected with TLR4-siRNA.(3)The expression of TLR2,MyD88 mRNA in TLR4 (RNAi) group significantly decreased contrast with normal group.Meanwhile the expression of TLR2,MyD88 mRNA and TNF-α protein also obviously reduced in TLR4(RNAi) +Af group when compared with N +Af group.Compared with TLR4 (RNAi) group,the expression of MyD88 mRNA in TLR4 (RNAi) +Af group significantly increased.However,the expression of TLR2 mRNA and TNF-α protein have no significant change after silencing gene of TLR4.Conclusion Signaling pathway of TLR2 and TLR4 in macrophages was activated by given stimulus of Aspergillusfumigatus conidia and exerted the effect of anti-Aspergillus fumigatus spores stimulation through the release of pro-inflammatory cytokines TNF-α.Meanwhile,silencing gene of TLR4 down-regulate the effect of TLR2 signal transduction in RAW264.7 cells to anti-Aspergillus fumigatus conidia stimulation,and it found that TLR4 played an more important role by contrast with TLR2.
2.Research on the relation between the content of thiol group and in vitro adhesion of the chitosan-thioglycolic acid conjugates
Ganjun YUAN ; Qiuling SU ; Hongqian HUANG ; Xingliang SHEN ; Mingsheng LIU ; Demei CHEN
Chinese Journal of Marine Drugs 1994;0(01):-
Objective Research on the relation between the content of thiol group in chitosan-thioglycolic acid conjugates and in vitro adhesion. Methods Prepared chitosan-thioglycolic acid conjugates with different content of thiol group,and determined the swelling behavior,instant detachment force between test disc and mucosa,recorded the maximum detachment force(MDF),and calculated the total work of adhesion(TWA)of these samples.Results The relation between the content of thiol groups and in vitro adhesion of the chitosan-thioglycolic acid conjugates was positive correlation, the adhesion of the polymer increased along with the content of thiol group,but the rate decreased.Conclusion The adhesion of chitosan-thioglycolic acid conjugates with higher content of thiol gyoup was far more stronger than chitosan.