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PubMed · 11037977

Monocyte:astrocyte interactions regulate MCP-1 expression in both cell types.

A V Andjelkovic·D Kerkovich·J S Pachter
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Abstract

As astrocytes are a source of monocyte chemoattractant protein-1 (MCP-1) and lie in close apposition to brain microvessels, interactions between astrocytes and infiltrating monocytes might regulate production of this chemokine. To investigate this possibility, a monocyte:astrocyte co-culture model was utilized to assess the respective roles of these two cell types in regulating MCP-1 production. Results indicate that, while neither monocytes nor astrocytes alone produce detectable levels of MCP-1, co-culture of these two cell types results in time-dependent production of this chemokine. Such production requires de novo protein synthesis and is dependent on physical contact between monocytes and astrocytes, involving engagement of the cell-adhesion molecules ICAM-1 and VCAM-1. Additionally, interleukin 1-beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) are soluble mediators of this response. These findings imply that monocyte extravasation into the CNS may be critically regulated at the blood-brain barrier by specialized monocyte:astrocyte interactions.

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AstrocytesCell AdhesionCell CommunicationCells, CulturedChemokine CCL2Coculture TechniquesGene Expression RegulationHumansIntercellular Adhesion Molecule-1Interleukin-1MonocytesTumor Necrosis Factor-alphaVascular Cell Adhesion Molecule-1Comparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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A V Andjelkovic, D Kerkovich, J S Pachter. 2000. Monocyte:astrocyte interactions regulate MCP-1 expression in both cell types.. https://pubmed.ncbi.nlm.nih.gov/11037977/

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