Plasma Levels of Endothelial Microparticles Bearing Monomeric C-reactive Protein are Increased in Peripheral Artery Disease

  • Jeffrey R. Crawford
  • JoAnn TrialEmail author
  • Vijay Nambi
  • Ron C. Hoogeveen
  • George E. Taffet
  • Mark L. Entman
Original Article


C-reactive protein (CRP) as an indicator of cardiovascular disease (CVD) has shown limited sensitivity. We demonstrate that two isoforms of CRP (pentameric, pCRP and monomeric, mCRP) present in soluble form or on microparticles (MPs) have different biological effects and are not all measured by clinical CRP assays. The high-sensitivity CRP assay (hsCRP) did not measure pCRP or mCRP on MPs, whereas flow cytometry did. MPs derived from endothelial cells, particularly those bearing mCRP, were elevated in peripheral artery disease (PAD) patients compared to controls. The numbers of mCRP+ endothelial MPs did not correlate with hsCRP measurements of soluble pCRP, indicating their independent modulation. In controls, statins lowered mCRP+ endothelial MPs. In a model of vascular inflammation, mCRP induced endothelial shedding of MPs and was proinflammatory, while pCRP was anti-inflammatory. mCRP on endothelial MPs may be both an unmeasured indicator of, and an amplifier of, vascular disease, and its detection might improve risk sensitivity.


CRP Peripheral artery disease Monomeric CRP Pentameric CRP hsCRP Inflammation Microparticle 



C-reactive protein


high-sensitivity CRP assay


monomeric CRP


mononuclear leukocyte




peripheral artery disease


pentameric CRP


transendothelial migration



We are grateful for the CRP antibody donation of Dr. Larry Potempa (Roosevelt University, Chicago, Illinois). We would like to thank all subjects who participated in the study, Tenille Epperson and Joe L. Raya for their technical assistance and the MD Anderson Cancer Center Flow Cytometry Core for their assistance with the Amnis cytometer.

Compliance with Ethical Standards

The study was conducted in accordance with the ethical standards of the Helsinki declaration and its later amendments and with the ethical standards and approval of the Institutional Review Board of Baylor College of Medicine. Informed consent was obtained from all individual participants included in the study. No animal studies were carried out by the authors for this article.

Sources of Funding

This work was supported by the National Institutes of Health [T32AI053831-10 to J.R.C., RO1 HL-089792 to M.L.E.], Bethesda, Maryland; the Hankamer Foundation, Houston, Texas; the Vivian L. Smith Foundation, Houston, Texas; and The Medallion Foundation, Houston, Texas.

Conflict of Interest

V.N. and R.C.H. are co-investigators on a provisional patent filed by Roche for use of biomarkers in heart failure prediction. The other authors declare that this research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The views expressed in this article are those of the authors and do not necessarily represent the views of the Department of Veterans Affairs. V.N. has indicated that he has served on the regional advisory board (once) for Sanofi-Regeneron.

Supplementary material

12265_2016_9678_MOESM1_ESM.pdf (726 kb)
ESM 1 (PDF 725 kb)


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Jeffrey R. Crawford
    • 1
  • JoAnn Trial
    • 1
    Email author
  • Vijay Nambi
    • 2
    • 3
    • 4
  • Ron C. Hoogeveen
    • 3
  • George E. Taffet
    • 1
  • Mark L. Entman
    • 1
  1. 1.The Division of Cardiovascular Sciences and the DeBakey Heart Center, Department of MedicineBaylor College of Medicine and Houston Methodist HospitalHoustonUSA
  2. 2.The Division of CardiologyMichael E. DeBakey Veterans Affairs Medical CenterHoustonUSA
  3. 3.The Division of Atherosclerosis and Vascular Medicine, Department of MedicineBaylor College of MedicineHoustonUSA
  4. 4.Center for Cardiovascular PreventionMethodist DeBakey Heart and Vascular CenterHoustonUSA

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