TNF-α-induced Regulation and Signalling in Macrophages

doi:10.1016/S0171-2985(96)80017-9

Immunobiology

Volume 195, Issues 4–5, October 1996, Pages 477-490

https://doi.org/10.1016/S0171-2985(96)80017-9 Get rights and content

Abstract

Tumor necrosis factor α (TNF-α) is a pleiotropic cytokine produced predominantly by macrophages. In addition, macrophages respond to TNF-α by differentiating to express different groups of gene products. Our laboratory recently showed that the context in which TNF-α is recognized by macrophages dramatically impacts the pattern of gene expression and hence investigating the mechanism of TNF-α signal transduction will be important in understanding how this molecule regulates macrophage differentiation. TNFcc is recognized by two cell surface receptors, CD120a (p55) and CD120b (p75) that belong to the TNF/NGF receptor family. Signalling is initiated by receptor multimerization in the plane of the plasma membrane. The initial signalling events activated by receptor cross-linking are unknown although activation of the mitogen-activated protein kinase (MAPK) cascade occurs shortly after ligand binding to CD120a (p55). We have investigated the upstream kinases that mediate the activation of p42^mapk/erk2 following cross-linking of CD120a (p55) in mouse macrophages. Exposure of mouse macrophages to TNF-a stimulated a time-dependent increase in the activity of MEK1, that temporally preceded peak activation of p42^mapk/erk2. MEKs, dual specificity T/Y kinases, act as a convergence point for serveral signalling pathways including Ras/Raf, MEKK and Mos. Incubation of macrophages with TNF-α was found to transiently stimulate an MEKK that peaked in activity within 30 sec of exposure and progressively declined towards basal levels by 5 min. By contrast, under these conditions, activation of either c-Raf-1 or Raf-B was not detected. These data suggest that the activation of the MAPK cascade in response to TNF-α is mediated by the sequential activation of an MEKK and MEK1 in a c-Raf-1 and Raf-B-independent fashion. The implications of these findings will be discussed in the context of the regulation of macrophage gene expression.

References (31)

C.V. DE WHALLEY et al.
Influence of the cytocidal macrophage phenotype on the degradation of acetylated low density lipoproteins: dual regulation of scavenger receptor activity and of intracellular degradation of endocytosed ligand
Exp. Cell. Res.
(1991)
I. HERSKOWITZ
MAP kinase pathways in yeast: For mating and more
Cell.
(1995)
E. CANO et al.
Parallel signal processing among mammalian MAPKs
TIBS.
(1995)
R. DAvis
MAPKs: new JNK expandts the group
TIBS.
(1994)
J. COOPER
Straight and narrow or tortuous and intersecting? Curr
Biol.
(1994)
L.A. TARTAGLIA et al.
Two TNF receptors
Immunol. Today.
(1992)
B.W. WINSTON et al.
Preferential involvement of MEK1 in the TNF-α induced activation of p42^maPk/erk2 in mouse macrophages
J. Biol. Chem.
(1995)
C.M.M. HAYSTEAD et al.
Insulin activates a novel adipocyte mitogen-activated protein kinase that shows rapid phasic kinetics and is distinct from c-Raf
J. Biol. Chem.
(1994)
B. DERIJARD et al.
JNK1: A protein kinase stimulated by UV light and Ha-Ras that binds and phosphorylates the c-Jun activation domain
Cell.
(1994)
J.G.S. RAINGEAUD et al.
Pro-inflammatory cytokines and environmental stress cause p38 mitogen-activated protein kinase activation by dual phosphorylation on tyrosine and threonine
J. Biol. Chem.
(1995)

O.A. COSO et al.

The small GTP-binding proteins Rac1 and Cdc42 regulate the activity of the JNK/SAPK signalling pathway

Cell.

(1995)

A. MINDEN et al.

Selective activation

of the JNK signaling cascade and c-Jun transcriptional activity by the small GTPases Rac and Cdc42Hs. Cell.

(1995)

D.W.H. RiCHEs

The Molecular and Cellular Biology of Wound Repair

(1995)

F.R. LAKE et al.

Functional switching of macrophages responses to TNF-α by interferons

Implications for the pleiotropic activities of TNF-α. J. Clin. Invest.

(1994)

P.W. NOBLE et al.

Hyaluronate activation of CD44 induces insulin-like growth factor-1 expression by a tumor necrosis factor-α-dependent mechanism in murine macrophages

J. Clin. Invest.

(1993)

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CHAPTER 7 - TNF-α-induced Regulation and Signalling in Macrophages

Abstract

Exp. Cell. Res.

Cell.

TIBS.

TIBS.

Biol.

Immunol. Today.

J. Biol. Chem.

J. Biol. Chem.

Cell.

J. Biol. Chem.

Cell.

of the JNK signaling cascade and c-Jun transcriptional activity by the small GTPases Rac and Cdc42Hs. Cell.

The Molecular and Cellular Biology of Wound Repair

Functional switching of macrophages responses to TNF-α by interferons

Implications for the pleiotropic activities of TNF-α. J. Clin. Invest.

Hyaluronate activation of CD44 induces insulin-like growth factor-1 expression by a tumor necrosis factor-α-dependent mechanism in murine macrophages

J. Clin. Invest.