Tumor necrosis factor mutants with selective cytotoxic activity.
Tumor necrosis factor (TNF-alpha) has a cytotoxic or cytostatic effect when tested with various malignant cell lines. Clinical trials in cancer patients, however, revealed high systemic toxicity of TNF-alpha. The existence of two types of receptor may partially explain the pleiotropic activity of TNF-alpha. The purpose of this study was to characterize the relative cytotoxic activity of TNF-alpha and TNF mutants on the mouse fibrosarcoma L929 cells in a standard cytotoxicity test, on human larynx carcinoma HEp-2 cells, and on human monoblastoid leukemic cells U937. TNF mutants were obtained by site-directed mutagenesis. The purity of TNF-alpha was established by capillary electrophoresis. TNF-alpha and TNF mutants were analysed by Western blot analysis using monoclonal antibodies against TNF-alpha. The results show that TNF mutants can recognize the different TNF-receptors (TNF-R) selectivity. It is generally believed that activation of TNF-R75 is responsible for the systemic toxicity of TNF-alpha. Hence, the development of TNF mutants, binding selectively to TNF-R55, could lead to new option for an anticancer treatment that would be devoid of the deleterious effect of TNF-alpha.
Berkova
N
N
Centre de Recherche, Endocrinologie de la Reproduction, Pavillon Saint-François d'Assise, CHUQ, Quebec, Canada.
Lemay
A
A
Korobko
V
V
Shingarova
L
L
Sagaidak
L
L
Goupil
S
S
D000818:Animals; D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology*; D015153:Blotting, Western; D002470:Cell Survival / Q000187:drug effects; D019075:Electrophoresis, Capillary; D006801:Humans; D051379:Mice; D009369:Neoplasms / Q000188:drug therapy*; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D014407:Tumor Cells, Cultured / Q000187:drug effects* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000494:pharmacology*
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000970:Antineoplastic Agents; D018124:Receptors, Tumor Necrosis Factor; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D014409:Tumor Necrosis Factor-alpha