A proteomic analysis of C-reactive protein stimulated THP-1 monocytes

Background: c-reactive protein (crp) is a predictor of cardiovascular risk. it circulates as a pentameric protein in plasma. recently,a potential dissociation mechanism from the disc-shaped pentameric crp (pcrp) into single monomers (monomeric or mcrp) has been described. it has been shown that mcrp has strong pro-inflammatory effects on monocytes. to further define the role of mcrp in determining monocyte phenotype,the effects of crp isoforms on thp-1 protein expression profiles were determined. the hypothesis to be tested was that mcrp induces specific changes in the protein expression profile of thp-1 cells that differ from that of pcrp.methods: protein cell lysates from control and mcrp,pcrp or lps-treated thp-1 cells were displayed using 2-dimensional sds page and compared. differentially expressed proteins were identified by maldi-tof ms and confirmed by western blotting.results: mcrp significantly up-regulates ubiquitin-activating enzyme e1,a member of the ubiquitin-proteasome system in thp-1 monocytes. furthermore,hsp 70,alpha-actinin-4 (actn4) and alpha-enolase/enolase 1 were upregulated. the proteomic profile of lps and pcrp treated monocytes differ significantly from that of mcrp.conclusion: the data obtained in this study support the hypothesis that isoform-specific effects of crp may differentially regulate the phenotype of monocytes. © 2011 eisenhardt et al; licensee biomed central ltd.