Characterization of receptors for human tumour necrosis factor and their regulation by γ-interferon

• Published in: Nature (London) 1985-12, Vol.318 (6047), p.665-667
• Main Authors: Aggarwal, Bharat B, Eessalu, Thomas E, Hass, Philip E
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Cell Line; Cell receptors; Cell structures and functions; Female; Fundamental and applied biological sciences. Psychology; Glycoproteins - metabolism; Humanities and Social Sciences; Humans; Interferon-gamma - pharmacology; Iodine - metabolism; letter; Molecular and cellular biology; Molecular Weight; multidisciplinary; Receptors, Cell Surface - metabolism; Receptors, Tumor Necrosis Factor; Recombinant Proteins - metabolism; Science; Science (multidisciplinary); Substrate Specificity; Time Factors; Tumor Necrosis Factor-alpha; Uterine Cervical Neoplasms - analysis
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/318665a0

Tumour necrosis factors, TNF- α and TNF- β (previously called lymphotoxin), are the products of activated monocytes and lymphocytes, respectively, and both have recently been purified, sequenced and cloned by recombinant DNA methods 1–5 , revealing 35% identity and 50% homology in the amino-acid sequence. Both proteins have been found to be specifically toxic to many tumour cells. Furthermore, it has been reported that various interferons are synergistic with TNF for anti-tumour effects in vitro 6–8 , while activities attributed to the two proteins have also been shown to necrotize various tumours in vivo 2,3,9 . We have now prepared 125 I-labelled highly purified recombinant human TNF- α to study in detail its binding to the human cervical carcinoma cell line ME-180. Our results indicate that there is a single class of specific high-affinity receptors for TNF on this cell line which has a K d of about 0.2 nM and an average of 2,000 receptor sites per cell. The binding of labelled TNF- α to these cells can be inhibited by both TNF- α and TNF- β but not by γ -interferon (IFN- γ ). However, preincubation of cells with IFN- γ increases the total number of TNF receptors two to threefold without any significant change in the affinity constant. This is the first report that TNF- α and - β share a common receptor and that the receptors can be up-regulated by interferon. Our results may explain previous observations regarding similar biological activities observed for these two cytotoxic proteins and also their synergistic action with interferons.