Regulation of monocyte function by complement activation products.

R M Antrum; J S Solomkin

doi:10.1016/0022-4804(85)90063-0

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Regulation of monocyte function by complement activation products.

R M Antrum·J S Solomkin

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Abstract

Normal human monocytes, obtained at a mean purity of 60% by Percoll density gradient centrifugation, were found to be chemotactically deactivated to C5a by exposure to low, and biologically significant, concentrations of zymosan-activated serum (ZAS), while retaining their full response to FMLP. C5a was found to be 40X more potent than its metabolite C5adesArg in reducing chemotaxis to activated pooled serum. Conversely, exposure of monocytes to varying concentrations of N-formyl-methionyl-leucyl-phenylalanine (FMLP) decreased chemotaxis to that attractant, though had no effect on chemotaxis to activated serum. Monocytes were also found to actively absorb C5a from solutions of ZAS, rich in C5a. Our data support the concept that monocytes are specifically regulated by C5a and C5adesArg.

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Blood Chemotactic Factors Complement Activation Complement C5 Complement C5a Dose-Response Relationship, Drug Humans Monocytes N-Formylmethionine Leucyl-Phenylalanine Zymosan Journal Article Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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R M Antrum, J S Solomkin. 1985. Regulation of monocyte function by complement activation products.. https://doi.org/10.1016/0022-4804(85)90063-0

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