Functional requirement of the two TNF receptors for induction of apoptosis in PC60 cells and the role of mitochondria in TNF-induced cytotoxicity.
The rat/mouse T-cell hybridoma PC60 was transfected either with hTNF-R55 cDNA, hTNF-R75 cDNA, or both. Receptor-specific stimulation was achieved using agonistic monoclonal antibodies or receptor-specific muteins of hTNF. Either hTNF-R55 or hTNF-R75 could mediate the activation of NF-kappa B and the induction of GM-CSF, IL-6, and IFN-gamma. But only in cells carrying both hTNF-R55 and hTNF-R75, was TNF able to induce apoptosis. This apoptosis could be inhibited almost completely by cotransfection with human bcl-2 cDNA. Functional cooperation was observed between liganded and unliganded receptors for the induction of apoptosis. In vitro protein kinase activity was detected only in TNF-R75 immunoprecipitates from cells in which the receptor was signaling. Direct evidence was obtained for reactive oxygen intermediates of mitochondrial origin responsible for TNF-induced cytotoxicity in L929 cells.
Vandenabeele
P
P
Laboratory of Molecular Biology, University of Gent, Belgium.
Goossens
V
V
Beyaert
R
R
Declercq
W
W
Grooten
J
J
Vanhaesebroeck
B
B
Van de Craen
M
M
Vercammen
D
D
Depuydt
B
B
Denecker
G
G
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D006801:Humans; D006825:Hybridomas / Q000502:physiology / Q000648:ultrastructure; D051379:Mice; D008928:Mitochondria / Q000502:physiology*; D051381:Rats; D018124:Receptors, Tumor Necrosis Factor / Q000235:genetics / Q000502:physiology*; D015398:Signal Transduction; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha