ABSTRACT
Objective To construct a shRNA lentiviral vector targeting the gene encoding tumor necrosis factor alpha-induced protein 8 (TNFAIP8) in RAW264. 7 cells, a mouse macrophage cell line, and to investigate the effects of TNFAIP8 gene silencing on the functions of mouse macrophages. Methods The shRNA sequence targeting TNFAIP8 gene was designed and DNA oligos containing small hairpin frame was synthesized. The double-stranded DNA was cloned into pLKO. 1-TRC vector after annealing. The recombi-nant vector was verified by using double enzyme digestion and gene sequencing. Lentiviruses were prepared by transfecting the constructed vector into 293T cells. Fluorescent quantitative RT-PCR and Western blot as-say were performed to detect the expression of TNFAIP8 at mRNA and protein levels after infecting the RAW264. 7 cells with lentiviruses. Flat dish adhesion experiment and wound-healing assay were used to evaluate the effects of TNFAIP8 gene silencing on the adhesion and migration of RAW264. 7 cells. Results The recombinant lentiviral vector was successfully constructed as indicated by double enzyme di-gestion and gene sequencing analysis. The expression of TNFAIP8 in RAW264. 7 cells at both mRNA and protein levels were significantly down-regulated after lentivirus infection (P<0. 05). Moreover, TNFAIP8 gene silencing significantly impaired the cell adhesion ability of RAW264. 7 cells after 15 min, 30 min or 2 hours of culture. Compared with the cells in control group, the RAW264. 7 cells harboring silenced TN-FAIP8 gene looked round with a smaller number of cellular extensions. The wound-healing assay showed that less TNFAIP8 gene-silenced RAW264. 7 cells migrated into the wounded area as compared with the cells in control group after 24 hours of culture (P<0. 05). The wound-healing rates of the experimental and control groups were 25% and 50%, respectively. Conclusion The recombinant lentiviral vector containing shRNA targeting the TNFAIP8 gene was successfully constructed. Transfecting the RAW264. 7 cells with the con-structed vector significantly silenced the expression of TNFAIP8 gene and inhibited the adhesion and migra-tion of these cells.
ABSTRACT
Objective:In order to get recombinant protein OCILRP 2-Fc and anti-OCILRP2 antibody for further study of OCILRP2.Methods:Eukaryotic expression vector pIg-CD5-OCILRP2 which fused with extracellular domain of OCILRP 2 and human IgG1 Fc fragment was constructed.G418 was used for stable expression cell strain after pIg-CD5-OCILRP2 transfected into CHO cells.Recombinant protein OCILRP 2-Fc purified from CHO cell supernatant was used to immunize rabbit and anti-OCILRP2 polyclonal antibody was purified from rabbit serum by using protein G column.Results: ELISA data showed that we got a high-titer anti-serum and anti-OCILRP2 antibody purified from the rabbit serum.Western blot indicated this antibody could specifically bind to OCILRP 2-Fc and OCILRP2 in NIH/3T3 lysate.OCILRP2 expression in murine bone marrow derived dendritic cells ( DC) was detected by this polyclonal antibody ,too.Compared to immature DC ,OCILRP2 expression was elevated in LPS induced-mature DC.Conclusion: This study has offered an available tool and provided a clue for further study of the roles of OCILRP 2 in immune response.
ABSTRACT
Objecitv e To investigate the effects of a recombinant protein osteoclast inhibitory lectin related protein 2( OCILRP2)-Fc on LPS-induced endotoxemia by blocking OCILRP 2 signaling pathway and to in-vestigate the roles of OCILRP2 during inflammation.Methods Real-time PCR was used to detect OCILRP2 ex-pression at mRNA level in RAW264.7cells before and after in vitro stimulation with LPS.A mouse model of en-dotoxemia was established by intraperitoneal injection of BALB /c mice with a median lethal dose of LPS .Two hours prior to LPS treatment, mice were intraperitoneally injected with OCILRP2-Fc, human IgG or PBS, re-spectively .Several parameters including the survival rate of BALB/c mice with and without LPS treatment , spleen weight for arterial hyperemia analyzing , histopathological changes of lung and liver by HE staining , serum levels of inflammatory cytokines (IL-6, IL-12, TNF-αand IFN-γ)by ELISA , NF-κB activity by Western blot, were analyzed .Results Real-time PCR showed that LPS elevated in vitro OCILRP2 expression at mRNA level in macrophages (P<0.05).Upon the treatment of OCILRP2-Fc, BALB/c mice suffered from endotoxemia showed obviously increased survival rate , decreased spleen hyperemia , attenuated pathological injury of lung and liver, reduced levels of IL-6, IL-12, TNF-αand IFN-γin serum samples (P <0.05) as compared with mice treated with human IgG and PBS .LPS induced NF-κB p65 phosphorylation and IκB degradation were inhibited by OCILRP2-Fc treatment.Conclusion OCILRP2-Fc protects mice from endotoxemia by blocking OCILRP 2 signaling, which suggests that OCILRP2 plays an important role in LPS induced inflammation.