Is there a role of C-reactive protein in red blood cell aggregation?
BACKGROUND
Numerous clinical studies related the plasma level of C-reactive protein (CRP) to the erythrocyte sedimentation rate (ESR) independent of the kind of disease. The molecular regulation of the process is unknown.


METHODS
We performed a meta-analysis of 10 previous studies and experimentally probed for a direct action of CRP on red blood cells (RBCs) by different methods including determination of a microscopic aggregation index, Ca(2+) imaging and analysis of sedimentation experiments.


RESULTS
The meta-analysis revealed a statistically significant correlation (Pearson coefficient of 0.37; P < 0.0001), but we could not find any experimental evidence for a direct CRP-RBC interaction. Instead, we could confirm a correlation between fibrinogen level and ESR.


CONCLUSIONS
Therefore, we concluded that CRP and ESR cannot account for nor replace each other as a diagnostic measure. The correlation between CRP level and ESR is most probably caused by fibrinogen, because its increase coincides with elevated CRP levels.
Experimental Physics, Saarland University, Saarbrücken, Germany.
D
D
Flormann
Institute for Molecular Cell Biology and Research Centre for Molecular Imaging and Screening, School of Medicine, Saarland University, Homburg/Saar, Germany.
E
E
Kuder
Institute for Molecular Cell Biology and Research Centre for Molecular Imaging and Screening, School of Medicine, Saarland University, Homburg/Saar, Germany.
P
P
Lipp
Experimental Physics, Saarland University, Saarbrücken, Germany.
C
C
Wagner
Institute for Molecular Cell Biology and Research Centre for Molecular Imaging and Screening, School of Medicine, Saarland University, Homburg/Saar, Germany.
L
L
Kaestner
D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000175:diagnosis; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000378:metabolism*; D002118:Calcium / Q000097:blood; D003093:Colitis, Ulcerative / Q000097:blood* / Q000175:diagnosis; D004696:Endocarditis / Q000097:blood* / Q000175:diagnosis; D004903:Erythrocyte Aggregation; D004912:Erythrocytes / Q000378:metabolism / Q000473:pathology; D005340:Fibrinogen / Q000378:metabolism; D006801:Humans; D057054:Molecular Imaging; D010019:Osteomyelitis / Q000097:blood* / Q000175:diagnosis; D010195:Pancreatitis / Q000097:blood* / Q000175:diagnosis; D012044:Regression Analysis; D012720:Severity of Illness Index
D005340:Fibrinogen; D002097:C-Reactive Protein; D002118:Calcium
C-reactive protein; aggregation index; erythrocyte sedimentation rate; thrombotic risk