Dual function of human necrosis factor receptor 75 in cytotoxicity induced by human tumor necrosis factor alpha
Abstract
Aim: To study the function of human TNF receptor-75 (hTR75) and the interaction between human TNF receptor-55 (hTR55) and hTR75 in hTNFalpha-induced cytotoxicity.
Methods: HEp-2 cells were transfected with bicistronic expression vector of hTR75 gene, and HEp-2-A75 cells with intrinsic hTR55 and overexpressed hTR75 were obtained. Two hTNFalpha muteins with exclusive specificity for hTR55 or hTR75 were constructed, expressed in high-levels in E coli, and then purified. hTNFalpha-induced cytotoxicity was determined by crystal violet colorimetric method.
Results: The expression of hTR75 in HEp-2 cells was demonstrated by RT-PCR and indirect ELISA, and was quantified by binding of [125I]hTNFalpha and Scatchard analysis. The overexpressed hTR75 could markedly increase the susceptibility of HEp-2 cells to hTNFalpha.
Conclusion: hTR75 could not only partially mediate hTNFalpha-induced cytotoxicity independently but also fulfill an accessory role in enhancing or synergizing hTR55-mediated cytotoxicity. It played a dual function in hTNFalpha-induced cytotoxicity in HEp-2 cells.
Keywords:
Methods: HEp-2 cells were transfected with bicistronic expression vector of hTR75 gene, and HEp-2-A75 cells with intrinsic hTR55 and overexpressed hTR75 were obtained. Two hTNFalpha muteins with exclusive specificity for hTR55 or hTR75 were constructed, expressed in high-levels in E coli, and then purified. hTNFalpha-induced cytotoxicity was determined by crystal violet colorimetric method.
Results: The expression of hTR75 in HEp-2 cells was demonstrated by RT-PCR and indirect ELISA, and was quantified by binding of [125I]hTNFalpha and Scatchard analysis. The overexpressed hTR75 could markedly increase the susceptibility of HEp-2 cells to hTNFalpha.
Conclusion: hTR75 could not only partially mediate hTNFalpha-induced cytotoxicity independently but also fulfill an accessory role in enhancing or synergizing hTR55-mediated cytotoxicity. It played a dual function in hTNFalpha-induced cytotoxicity in HEp-2 cells.