Role of C-Reactive Protein at Sites of Inflammation and Infection.
Level 5 - mechanism / opinion, no new human data
Narrative review of biological mechanisms and laboratory findings without new human empirical data
PubMed 29706967 · doi:10.3389/fimmu.2018.00754
What was done
Narrative review synthesizing evidence regarding the production, structure, and functional roles of C-reactive protein (CRP) isoforms—native homopentameric CRP (nCRP) and dissociated monomeric CRP (mCRP)—in host defense, complement activation, apoptosis, phagocytosis, nitric oxide (NO) signaling, and cytokine regulation.
What was found
The abstract reports no primary statistical metrics or participant numbers, but notes CRP can increase up to 1,000-fold during infection or inflammation. The isoforms exhibit distinct properties: nCRP activates the classical complement pathway, induces phagocytosis, promotes apoptosis, and inhibits NO production. In contrast, mCRP recruits circulating leukocytes, delays apoptosis, induces NO production, and increases interleukin-8 and monocyte chemoattractant protein-1, which nCRP does not alter.
Why it matters
Highlights that CRP acts as an active immune regulator rather than just an inert systemic biomarker, emphasizing that nCRP and mCRP exert opposing pro- and anti-inflammatory functions.
Limits
As a narrative review, it presents no original clinical or experimental dataset. Historical CRP literature is heavily confounded by unmeasured isoform dissociation and potential lipopolysaccharide contamination, while widespread investigation of mCRP remains hindered by the lack of commercially available specific antibodies.
Cited by
- supports C-reactive protein (CRP) is synthesized by hepatocytes in the liver.