Immunohistochemical localization of modified C-reactive protein antigen in normal vascular tissue.

BACKGROUND

The prototypic acute phase reactant, C-reactive protein (CRP), is a serum soluble, cyclic pentameric protein, the concentration of which increases markedly within hours of any tissue-damaging, inflammatory event. However, upon dissociation of its pentameric quaternary structure, CRP subunits undergo a spontaneous and irreversible conformational change. The resulting molecule, termed modified CRP or mCRP, has reduced aqueous solubility and a propensity to aggregate into a matrix-like lattice structure.

METHODS

Using monoclonal antibodies, normal human tissues were immunohistochemically screened for the presence of CRP as well as mCRP antigens.

RESULTS

Significant levels of mCRP were detected in the walls of blood vessels associated with normal human tissues. These data indicate that mCRP is a naturally occurring form of CRP and that it is a tissue-based rather than serum-based molecule.

SIGNIFICANCE

This report describes the localization of a stable form of CRP, mCRP, in blood vessels associated with normal human tissues.