In order to investigate the effects of LPS on the TACE gene transcription and expression and its regulating effect on the TM TNF secretion, in vitro studies were carried out on HL 60 cells stimulated by LPS. TACE, T...In order to investigate the effects of LPS on the TACE gene transcription and expression and its regulating effect on the TM TNF secretion, in vitro studies were carried out on HL 60 cells stimulated by LPS. TACE, TNF α mRNA levels were detected by Dot Elisa and the distribution of membrane molecules determined by flow cytometry assay and indirect immunofluorescence. The results showed that: (1) TACE was detected in or on HL 60 cells and it is predominantly localized on cell surface and to a perinuclear compartment. (2) LPS induced a time dependent increasement of TNF α mRNA and enhanced TNF conversion with decreasing distribution of TNF in cell surface and increasing secretion of TNF protein. Such conversion could be inhibited by TACE ODN. (3) LPS also induced time dependently increased expression of TACE gene and activation of its function. On the other hand, TACE protein in cell lysate and on cell surface was decreased. It was suggested that TACE molecular structure might change following its mediating membrane anchored molecular secretion.展开更多
基金This projectwas supported by a grant from National Nat-ural Sciences Fundation of China (No. 30 0 70 72 2 )
文摘In order to investigate the effects of LPS on the TACE gene transcription and expression and its regulating effect on the TM TNF secretion, in vitro studies were carried out on HL 60 cells stimulated by LPS. TACE, TNF α mRNA levels were detected by Dot Elisa and the distribution of membrane molecules determined by flow cytometry assay and indirect immunofluorescence. The results showed that: (1) TACE was detected in or on HL 60 cells and it is predominantly localized on cell surface and to a perinuclear compartment. (2) LPS induced a time dependent increasement of TNF α mRNA and enhanced TNF conversion with decreasing distribution of TNF in cell surface and increasing secretion of TNF protein. Such conversion could be inhibited by TACE ODN. (3) LPS also induced time dependently increased expression of TACE gene and activation of its function. On the other hand, TACE protein in cell lysate and on cell surface was decreased. It was suggested that TACE molecular structure might change following its mediating membrane anchored molecular secretion.