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Objective:To investigate the effects of IRF 3 shRNA adenovirus on dynamic changes of early cytokines in LPS-stimulated primary Kupffer cells ( KCs ).Methods: Rat KCs were isolated and purified by means of in situ perfusion.After being infected with adenovirus carrying IRF 3 shRNA for 48 h, KCs were stimulated with LPS.Cell culture supernatants were collected respectively at 0,2,4 and 6 h after LPS stimulation as well as cells at 6 h.Supernatant cytokine secretion levels were detected by enzyme-linked immunosorbent assay ( ELISA).Intracellular gene expressions were tested by RT-PCR and Westeron blot.Results:IRF3 mRNA and protein were induced by LPS ,but suppressed by IRF 3 shRNA adenovirus in LPS-stimulated or non-stimulated KCs.IFN-βsecretions rose in the very early stage ( at 2 h) ,reached the peak at 4 h,and began to reduce but still remained high levels at 6 h after LPS stimulation in KCs.Interference adenovirus pretreatment suppressed IFN-βsecretions ( especially the secretion peak ) at each time point after LPS stimulation.IFN-βsecretions reached normal levels at 6 h after the stimulation in adenovirus-pretreated cells;TNF-αse-cretions rapidly increased in the very early stage and reached the peak at 2 h,then began to decrease gradually ,but remained high levels at 6 h after LPS stimulation in KCs.Interference adenovirus pretreatment inhibited LPS-induced TNF-αsecretions, especially the secretion peak;IL-1βsecretions did not increase untill 4 h, but reached a higher level at 6 h after LPS stimulation.Interference adenovirus suppressed IL-1βsecretions in the early stage of LPS stimulation;IL-10 secretions began to rise in the very early stage ,and gradually increased over time after LPS stimulation in KCs.Pretreatment of adenovirus with IRF 3 shRNA promoted upregulations of IL-10 secretions at each time point of the early of LPS stimulation.Conclusion:IRF3 gene expression can be silenced by IRF 3 shRNA ad-enovirus.IRF3 can promote its downstream signaling molecule IFN-βand pro-inflammatory cytokines including TNF-αand IL-1β,and block anti-inflammation cytokine IL-10 secretions in LPS-stimulated primary KCs.Therefore,IRF3 may play a central role in immune inflammatory injury of liver tissues.
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Objective:To investigate the changes of gene expression profile in lipopolysaccharide (LPS)-stimulated primary Kupffer cells ( KCs ) . Methods: Rat KCs were isolated and purified by means of in situ perfusion and density gradient centrifugation. After being identified by ink phagocytosis and ED2 staining test,KCs were stimulated with LPS. Gene expression profile were studied using gene microarrays,and the most significant upregulated gene was verified using real-time PCR. Results:27 genes were upregulated including Ces1f, Slc17a3, Slc21a4, Hsd17b2, Sorbs2, Ccdc116, Mgam, Myo5b, Etl4, Fabp1, Kif4b, Fosl1, Cyp4a1, Penk, Tmem221,Rpl5,Nr2f1,Hoxb1,Gpr165,Fam90a13p,Kpna6,Irak1bp1,Kcnh1 and 4 unnamed genes and 4 downregulated including Oc90,Tagln,Arxes2 and Olr830 in LPS-stimulated KCs. Among the upregulated genes, Ces1f was the most significant upregulatory gene. Real-time PCR confirmed that the levels of Ces1f were 23. 88 times higher in LPS-stimulated than control cells. Conclusion:There is a significant difference between LPS-stimulated and normal control cells in gene expression profile by microarray analysis,and Ces1f is the most significantly upregulated gene.
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Objective To investigate the impacts of adenovirus on the transfection efficiency and proliferative activity of primary Kupffer cells (KCs). Methods Rat liver KCs were separated and purified by density gradient centrifugation , and was then transfected with adenovirus carrying green fluorescence protein (GFP) gene at different multiplicity of infection (MOI). After 24 h, the transfection efficiency was evaluated by fluorescence microscope and flow cytometry. The proliferative activity of KCs was assessed by colorimetric method. Results The positive percentages of GFP staining cells were statistically different among different doses of adenovirus (MOI 0, 100, 300, 500, 700 and 900) under fluorescence microscopy or by flow cytometry (P 0.05 for all comparisons) by CCK8 assay. Conclusions KCs can effectively be transfected by GFP adenovirus; and with an increase in virus MOI, the transfection efficiency rises gradually. A higher dose of adenovirus may have a negative effect on cell proliferative.
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Objective To investigate the effects of interferon regulator factor 3 (IRF3) shRNA on the expression of TLR4 downstream signal molecules including IRF3-IFN-β, NF-κB/p38 MAPK-TNF-α/IL-1βand IL-10 in lipopolysaccharide (LPS)-stimulated Kupffer cells (KCs). Methods KCs were isolated from rats by in situ perfusion. The adenovirus strains carrying IRF3 shRNA were used for the transfection of purified KCs. The isolated KCs were randomly divided into four groups including adenovirus(-) LPS(-) treatment group, adenovirus(-) LPS(+) treatment group, adenovirus(+) LPS(-) treatment group and ad-enovirus(+) LPS(+) treatment group. The levels of cytokines in the supernatants of KC culture were detec-ted by enzyme-linked immunosorbent assay ( ELISA ) . Real-time PCR and Western blot assay were per-formed to analyze the expression of related cytokines at mRNA and protein levels, respectively. Results The expression of IRF3 at mRNA and protein levels in primary cultured KCs were induced by LPS. The cel-lular constitutive expression of IRF3 at mRNA level and the LPS-induced expression of IRF3 were signifi-cantly inhibited after transfection of KCs with adenovirus strains carrying IRF3 shRNA. However, the nucle-ar constitutive expression of IRF3 protein was not affected by IRF3 shRNA. The expression of IFN-βat mR-NA and protein levels in KCs were induced by LPS, but were suppressed by the interference with IRF3 shR-NA. No significant changes of the cellular constitutive expression of IFN-βat mRNA and protein levels were observed in IRF3 shRNA-treated KCs. Enhanced expression of proinflammatory cytokines including TNF-αand IL-1β at mRNA and protein levels were detected in LPS-stimulated KCs. Transfection of KCs with ade-novirus strains carrying IRF3 shRNA inhibited the LPS-induced secretion of TNF-α and IL-1β, but neither LPS-induced expression of TNF-α and IL-1β at mRNA level nor cellular constitutive expression of TNF-αand IL-1βat mRNA and protein levels were affected by IRF3 shRNA. The LPS-induced expression of IL-10 at mRNA and protein levels were enhanced in IRF3 shRNA-treated KCs. However, the cellular constitutive expression of IL-10 at mRNA and protein levels were not affected by the adenovirus. The levels of phosphor-NF-κB p65 subunit and phosphor-p38 MAPK protein in the nuclei of KCs were increased upon the stimula-tion with LPS. Treatment of KCs with IRF3 shRNA showed no significant effects on nuclear phosphor-NF-κB p65 subunit and phosphor-p38 MAPK. Conclusion Transfection of LPS-stimulated primary KCs with ade-novirus strains carrying IRF3 shRNA could effectively inhibit the expression of IRF3 and the transduction of downstream signals. IRF3 enhanced the secretion of TNF-αand IL-1β, but inhibited the expression of IL-10 in LPS-treated KCs. The LPS-induced activation of NF-κB and p38 MAPK in KCs were not affected by IRF3 signal.