TNF-α plus IFN-γ induce connexin43 expression and formation of gap junctions between human monocytes/macrophages that enhance physiological responses

Eliseo Eugenin, María C. Brañes, Joan W. Berman, Juan C. Sáez

Research output: Contribution to journalArticle

159 Citations (Scopus)

Abstract

In this work, the effects of bacterial LPS, TNF-α, and IFN-γ on gap junctional communication (dye coupling) and on the expression of connexin43 (immunofluorescence, immunoblotting, and RT-PCR) in monocytes/macrophages were studied. Freshly isolated human monocytes plated at high density and treated either with LPS plus IFN-γ or TNF-α plus IFN-γ became transiently dye coupled (Lucifer yellow) within 24 h. Cells treated with LPS, TNF-α, or IFN-γ alone remained dye uncoupled. In dye-coupled cells, the spread of Lucifer yellow to neighboring cells was reversibly blocked with 18 α-glycyrrhetinic acid, a gap junction blocker, but it was unaffected by oxidized ATP or probenecid, which block ionotropic ATP-activated channels and organic anion transporters, respectively. Abs against TNF-α significantly reduced the LPS plus IFN-γ-induced increase in dye coupling. In dye-coupled monocytes/macrophages, but not in control cells, both connexin43 protein and mRNA were detected, and their levels were higher in cells with an elevated incidence of dye coupling. In dye-coupled cells, the localization of connexin43 immunoreactivity was diffuse at perinuclear regions and thin cell processes. The addition of 18-α-glycyrrhetinic acid induced a profound reduction of monocyte/macrophage transmigration across a blood brain barrier model. It also induced a significant reduction in the secretion of metalloproteinase-2 in cells treated with TNF-α plus IFN-γ. We propose that some monocyte/macrophage responses are coordinated by connexin-formed membrane channels expressed transiently at inflammatory sites in which these cells form aggregates.

Original languageEnglish (US)
Pages (from-to)1320-1328
Number of pages9
JournalJournal of Immunology
Volume170
Issue number3
StatePublished - Feb 1 2003
Externally publishedYes

Fingerprint

Connexin 43
Gap Junctions
Monocytes
Macrophages
Coloring Agents
Glycyrrhetinic Acid
Organic Anion Transporters
Probenecid
Connexins
Metalloproteases
Blood-Brain Barrier
Ion Channels
Immunoblotting
Fluorescent Antibody Technique
Adenosine Triphosphate
Communication
Polymerase Chain Reaction
Messenger RNA
Incidence

ASJC Scopus subject areas

  • Immunology

Cite this

TNF-α plus IFN-γ induce connexin43 expression and formation of gap junctions between human monocytes/macrophages that enhance physiological responses. / Eugenin, Eliseo; Brañes, María C.; Berman, Joan W.; Sáez, Juan C.

In: Journal of Immunology, Vol. 170, No. 3, 01.02.2003, p. 1320-1328.

Research output: Contribution to journalArticle

@article{e5cd51996e824c2f8ede54ac7178d563,
title = "TNF-α plus IFN-γ induce connexin43 expression and formation of gap junctions between human monocytes/macrophages that enhance physiological responses",
abstract = "In this work, the effects of bacterial LPS, TNF-α, and IFN-γ on gap junctional communication (dye coupling) and on the expression of connexin43 (immunofluorescence, immunoblotting, and RT-PCR) in monocytes/macrophages were studied. Freshly isolated human monocytes plated at high density and treated either with LPS plus IFN-γ or TNF-α plus IFN-γ became transiently dye coupled (Lucifer yellow) within 24 h. Cells treated with LPS, TNF-α, or IFN-γ alone remained dye uncoupled. In dye-coupled cells, the spread of Lucifer yellow to neighboring cells was reversibly blocked with 18 α-glycyrrhetinic acid, a gap junction blocker, but it was unaffected by oxidized ATP or probenecid, which block ionotropic ATP-activated channels and organic anion transporters, respectively. Abs against TNF-α significantly reduced the LPS plus IFN-γ-induced increase in dye coupling. In dye-coupled monocytes/macrophages, but not in control cells, both connexin43 protein and mRNA were detected, and their levels were higher in cells with an elevated incidence of dye coupling. In dye-coupled cells, the localization of connexin43 immunoreactivity was diffuse at perinuclear regions and thin cell processes. The addition of 18-α-glycyrrhetinic acid induced a profound reduction of monocyte/macrophage transmigration across a blood brain barrier model. It also induced a significant reduction in the secretion of metalloproteinase-2 in cells treated with TNF-α plus IFN-γ. We propose that some monocyte/macrophage responses are coordinated by connexin-formed membrane channels expressed transiently at inflammatory sites in which these cells form aggregates.",
author = "Eliseo Eugenin and Bra{\~n}es, {Mar{\'i}a C.} and Berman, {Joan W.} and S{\'a}ez, {Juan C.}",
year = "2003",
month = "2",
day = "1",
language = "English (US)",
volume = "170",
pages = "1320--1328",
journal = "Journal of Immunology",
issn = "0022-1767",
publisher = "American Association of Immunologists",
number = "3",

}

TY - JOUR

T1 - TNF-α plus IFN-γ induce connexin43 expression and formation of gap junctions between human monocytes/macrophages that enhance physiological responses

AU - Eugenin, Eliseo

AU - Brañes, María C.

AU - Berman, Joan W.

AU - Sáez, Juan C.

PY - 2003/2/1

Y1 - 2003/2/1

N2 - In this work, the effects of bacterial LPS, TNF-α, and IFN-γ on gap junctional communication (dye coupling) and on the expression of connexin43 (immunofluorescence, immunoblotting, and RT-PCR) in monocytes/macrophages were studied. Freshly isolated human monocytes plated at high density and treated either with LPS plus IFN-γ or TNF-α plus IFN-γ became transiently dye coupled (Lucifer yellow) within 24 h. Cells treated with LPS, TNF-α, or IFN-γ alone remained dye uncoupled. In dye-coupled cells, the spread of Lucifer yellow to neighboring cells was reversibly blocked with 18 α-glycyrrhetinic acid, a gap junction blocker, but it was unaffected by oxidized ATP or probenecid, which block ionotropic ATP-activated channels and organic anion transporters, respectively. Abs against TNF-α significantly reduced the LPS plus IFN-γ-induced increase in dye coupling. In dye-coupled monocytes/macrophages, but not in control cells, both connexin43 protein and mRNA were detected, and their levels were higher in cells with an elevated incidence of dye coupling. In dye-coupled cells, the localization of connexin43 immunoreactivity was diffuse at perinuclear regions and thin cell processes. The addition of 18-α-glycyrrhetinic acid induced a profound reduction of monocyte/macrophage transmigration across a blood brain barrier model. It also induced a significant reduction in the secretion of metalloproteinase-2 in cells treated with TNF-α plus IFN-γ. We propose that some monocyte/macrophage responses are coordinated by connexin-formed membrane channels expressed transiently at inflammatory sites in which these cells form aggregates.

AB - In this work, the effects of bacterial LPS, TNF-α, and IFN-γ on gap junctional communication (dye coupling) and on the expression of connexin43 (immunofluorescence, immunoblotting, and RT-PCR) in monocytes/macrophages were studied. Freshly isolated human monocytes plated at high density and treated either with LPS plus IFN-γ or TNF-α plus IFN-γ became transiently dye coupled (Lucifer yellow) within 24 h. Cells treated with LPS, TNF-α, or IFN-γ alone remained dye uncoupled. In dye-coupled cells, the spread of Lucifer yellow to neighboring cells was reversibly blocked with 18 α-glycyrrhetinic acid, a gap junction blocker, but it was unaffected by oxidized ATP or probenecid, which block ionotropic ATP-activated channels and organic anion transporters, respectively. Abs against TNF-α significantly reduced the LPS plus IFN-γ-induced increase in dye coupling. In dye-coupled monocytes/macrophages, but not in control cells, both connexin43 protein and mRNA were detected, and their levels were higher in cells with an elevated incidence of dye coupling. In dye-coupled cells, the localization of connexin43 immunoreactivity was diffuse at perinuclear regions and thin cell processes. The addition of 18-α-glycyrrhetinic acid induced a profound reduction of monocyte/macrophage transmigration across a blood brain barrier model. It also induced a significant reduction in the secretion of metalloproteinase-2 in cells treated with TNF-α plus IFN-γ. We propose that some monocyte/macrophage responses are coordinated by connexin-formed membrane channels expressed transiently at inflammatory sites in which these cells form aggregates.

UR - http://www.scopus.com/inward/record.url?scp=0037307922&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0037307922&partnerID=8YFLogxK

M3 - Article

C2 - 12538692

AN - SCOPUS:0037307922

VL - 170

SP - 1320

EP - 1328

JO - Journal of Immunology

JF - Journal of Immunology

SN - 0022-1767

IS - 3

ER -