Epithelial Cells Produce C-Reactive Protein

Researchers studying the molecular basis for cardiovascular disease have found that the epithelial cells that line the arteries produce C-reactive protein (CRP), which has been linked to inflammatory processes.

Investigators at the University of California, Davis (USA), working with human aortic endothelial cells (HAEC) examined the effect of vascular smooth muscle cell (VSMC) and/or macrophage-conditioned media (MCM) on the growth of HAEC in culture. They used reverse transcription-polymerase chain reaction (RT-PCR) to detect the presence of CRP messenger RNA (mRNA) in HAEC, and they measured intracellular protein by Western blot and secreted protein by an enzyme-linked immunosorbent assay (ELISA).


Results published in the April 2005 issue of the American Journal of Pathology revealed that endothelial cells produced C-reactive protein. CRP production was stimulated by interleukin-1 and interleukin-6. While VSMC-conditioned media had no effect, incubation with MCM resulted in a significant twofold increase in the synthesis of both intracellular and secreted CRP. Inhibiting both interleukin-1 and interleukin-6 could reverse the effect of MCM.

"This is an extremely important finding,” said senior author Dr. Ishwarlal Jialal, professor of pathology and internal medicine at the University of California, Davis. "We have convincingly demonstrated in this paper that aortic and coronary artery endothelial cells produce and secrete C-reactive protein. The C-reactive protein produced by endothelial cells cannot only act on the endothelial cells, but also on macrophages and smooth muscle cells in the atheroma. This creates a vicious cycle, leading to plaque instability and rupture, and ultimately heart attacks and strokes.”