Autocrine Tumor Necrosis Factor (TNF) and Lymphotoxin (LT) α Differentially Modulate Cellular Sensitivity to TNF/LT-α Cytotoxicity in L929 Cells
Tumor necrosis factor (TNF) and lymphotoxin (LT) α are structurally and functionally related cytokines. We expressed the TNF and LT-α genes in murine fibrosarcoma L929r2 cells, which can be sensitized to TNF/LT-α–dependent necrosis by inhibitors of transcription or translation. Autocrine production...
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1998
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pubmed-21752302008-05-01 Autocrine Tumor Necrosis Factor (TNF) and Lymphotoxin (LT) α Differentially Modulate Cellular Sensitivity to TNF/LT-α Cytotoxicity in L929 Cells Decoster, Els Cornelis, Sigrid Vanhaesebroeck, Bart Fiers, Walter Regular Articles Tumor necrosis factor (TNF) and lymphotoxin (LT) α are structurally and functionally related cytokines. We expressed the TNF and LT-α genes in murine fibrosarcoma L929r2 cells, which can be sensitized to TNF/LT-α–dependent necrosis by inhibitors of transcription or translation. Autocrine production of murine TNF in L929r2 cells completely downmodulated the expression of the 55- and 75-kD TNF receptors, resulting in resistance to TNF/LT-α cytotoxicity. Partial downmodulation of the 55-kD receptor was observed in human TNF-producing L929r2 cells. In contrast, an unaltered TNF receptor expression was found on LT-α L929r2 transfectants. Hence, although similar cytotoxic effects are induced by extracellularly administered TNF and LT-α, endogenous expression of these cytokines fundamentally differs in the way they modulate TNF receptor expression. Unlike LT-α, secreted by the classical pathway, TNF is first formed as a membrane-bound protein, which is responsible for receptor downmodulation. To explore whether the different pathways for secretion of TNF and LT-α explain this difference, we examined the effect of membrane-bound LT-α expression. This was obtained by exchange of the classical signal sequence of LT-α for the membrane anchor of chicken hepatic lectin. Membrane retention of LT-α resulted indeed in receptor downmodulation and TNF/LT-α resistance. We conclude that membrane retention of newly synthesized TNF or LT-α is absolutely required for receptor downmodulation and TNF/LT-α resistance. The Rockefeller University Press 1998-12-28 /pmc/articles/PMC2175230/ /pubmed/9864375 Text en This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/). |
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Open Access Journal |
institution_category |
Foreign Institution |
institution |
US National Center for Biotechnology Information |
building |
NCBI PubMed |
collection |
Online Access |
language |
English |
format |
Online |
author |
Decoster, Els Cornelis, Sigrid Vanhaesebroeck, Bart Fiers, Walter |
spellingShingle |
Decoster, Els Cornelis, Sigrid Vanhaesebroeck, Bart Fiers, Walter Autocrine Tumor Necrosis Factor (TNF) and Lymphotoxin (LT) α Differentially Modulate Cellular Sensitivity to TNF/LT-α Cytotoxicity in L929 Cells |
author_facet |
Decoster, Els Cornelis, Sigrid Vanhaesebroeck, Bart Fiers, Walter |
author_sort |
Decoster, Els |
title |
Autocrine Tumor Necrosis Factor (TNF) and Lymphotoxin (LT) α Differentially Modulate Cellular Sensitivity to TNF/LT-α Cytotoxicity in L929 Cells |
title_short |
Autocrine Tumor Necrosis Factor (TNF) and Lymphotoxin (LT) α Differentially Modulate Cellular Sensitivity to TNF/LT-α Cytotoxicity in L929 Cells |
title_full |
Autocrine Tumor Necrosis Factor (TNF) and Lymphotoxin (LT) α Differentially Modulate Cellular Sensitivity to TNF/LT-α Cytotoxicity in L929 Cells |
title_fullStr |
Autocrine Tumor Necrosis Factor (TNF) and Lymphotoxin (LT) α Differentially Modulate Cellular Sensitivity to TNF/LT-α Cytotoxicity in L929 Cells |
title_full_unstemmed |
Autocrine Tumor Necrosis Factor (TNF) and Lymphotoxin (LT) α Differentially Modulate Cellular Sensitivity to TNF/LT-α Cytotoxicity in L929 Cells |
title_sort |
autocrine tumor necrosis factor (tnf) and lymphotoxin (lt) α differentially modulate cellular sensitivity to tnf/lt-α cytotoxicity in l929 cells |
description |
Tumor necrosis factor (TNF) and lymphotoxin (LT) α are structurally and functionally related cytokines. We expressed the TNF and LT-α genes in murine fibrosarcoma L929r2 cells, which can be sensitized to TNF/LT-α–dependent necrosis by inhibitors of transcription or translation. Autocrine production of murine TNF in L929r2 cells completely downmodulated the expression of the 55- and 75-kD TNF receptors, resulting in resistance to TNF/LT-α cytotoxicity. Partial downmodulation of the 55-kD receptor was observed in human TNF-producing L929r2 cells. In contrast, an unaltered TNF receptor expression was found on LT-α L929r2 transfectants. Hence, although similar cytotoxic effects are induced by extracellularly administered TNF and LT-α, endogenous expression of these cytokines fundamentally differs in the way they modulate TNF receptor expression. Unlike LT-α, secreted by the classical pathway, TNF is first formed as a membrane-bound protein, which is responsible for receptor downmodulation. To explore whether the different pathways for secretion of TNF and LT-α explain this difference, we examined the effect of membrane-bound LT-α expression. This was obtained by exchange of the classical signal sequence of LT-α for the membrane anchor of chicken hepatic lectin. Membrane retention of LT-α resulted indeed in receptor downmodulation and TNF/LT-α resistance. We conclude that membrane retention of newly synthesized TNF or LT-α is absolutely required for receptor downmodulation and TNF/LT-α resistance. |
publisher |
The Rockefeller University Press |
publishDate |
1998 |
url |
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2175230/ |
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1611425874898321408 |