Faculty Collaboration Database

TNF receptor I is required for induction of macrophage heat shock protein 70. Am J Physiol Cell Physiol 2001 Jul;281(1):C241-7

Date

06/13/2001

Pubmed ID

11401847

DOI

10.1152/ajpcell.2001.281.1.C241

Scopus ID

2-s2.0-0034816776 (requires institutional sign-in at Scopus site)   15 Citations

Abstract

Expression of heat shock proteins (HSP) is an adaptive response to cellular stress. Stress induces tumor necrosis factor (TNF)-alpha production. In turn, TNF-alpha induces HSP70 expression. However, osmotic stress or ultraviolet radiation activates TNF-alpha receptor I (TNFR-I) in the absence of TNF-alpha. We postulated that TNF-alpha receptors are involved in the induction of HSP70 by cellular stress. Peritoneal Mphi were isolated from wild-type (WT), TNF-alpha knockout (KO), and TNFR (I or II) KO mice. Cells were cultured overnight and then heat stressed at 43 +/- 0.5 degrees C for 30 min followed by a 4-h recovery at 37 degrees C. Cellular HSP70 expression was induced by heat stress or exposure to endotoxin [lipopolysaccharide (LPS)] as determined by immunoblotting. HSP70 expression induced by either heat or LPS was markedly decreased in TNFR-I KO Mphi, whereas TNFR-II KO Mphi exhibited HSP70 expression comparable to that in WT mice. Expression of HSP70 after heat stress in TNF-alpha KO Mphi was also similar to that in WT mice, suggesting that induction of HSP70 by TNFR-I occurs independently of TNF-alpha. In addition, levels of steady-state HSP70 mRNA were similar by RT-PCR in WT and TNFR-I KO Mphi despite differences in protein expression. Furthermore, the effect of TNFR-I appears to be cell specific, since HSP70 expression in splenocytes isolated from TNFR-I KO was similar to that in WT splenocytes. These studies demonstrate that TNFR-I is required for the synthesis of HSP70 in stressed Mphi by a TNF-independent mechanism and support an intracellular role for TNFR-I.

Author List

Heimbach JK, Reznikov LL, Calkins CM, Robinson TN, Dinarello CA, Harken AH, Meng X

Author

Casey Matthew Calkins MD Professor in the Surgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Cells, Cultured
Gene Expression Regulation
HSP70 Heat-Shock Proteins
Hot Temperature
Immunoblotting
Macrophages
Mice
Mice, Knockout
RNA
Receptors, Tumor Necrosis Factor
Spleen
Tumor Necrosis Factor-alpha