Increased in vitro differentiation of fibrocytes from keloid patients is inhibited by serum amyloid P

Authors

  • Michelle C. Naylor MD,

    1. Bobby R. Alford Department of Otolaryngology—Head & Neck Surgery, Baylor College of Medicine, Houston, Texas
    Search for more papers by this author
    • Contributed equally to this work as co-first authors
  • David A. Lazar MD,

    1. Division of Pediatric Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
    Search for more papers by this author
    • Contributed equally to this work as co-first authors
  • Irving J. Zamora MD,

    1. Division of Pediatric Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
    Search for more papers by this author
  • Oren P. Mushin MD,

    1. Division of Pediatric Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
    Search for more papers by this author
  • Ling Yu BS,

    1. Division of Pediatric Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
    Search for more papers by this author
  • Anthony E. Brissett MD,

    1. Bobby R. Alford Department of Otolaryngology—Head & Neck Surgery, Baylor College of Medicine, Houston, Texas
    Search for more papers by this author
  • Oluyinka O. Olutoye MB, ChB, PhD

    Corresponding author
    • Division of Pediatric Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
    Search for more papers by this author

  • Michelle Naylor, a first author of this manuscript, received a Young Investigator Award for presentation of this work at the 2010 annual meeting of the Wound Healing Society.

Reprint requests:

Dr. O. Olutoye, Texas Children's Hospital, 6701 Fannin Street, Suite 1210, Houston, TX 77030, USA.

Tel: +832 822 3135;

Fax: +832 825 3141;

Email: oolutoye@bcm.tmc.edu

Abstract

Keloid scarring is a form of fibroproliferative dermal wound healing characterized by growth beyond the confines of the original wound. Fibrocytes, derived from peripheral blood mononuclear cells and inhibited by serum amyloid P (SAP), have been linked to other fibroproliferative diseases. We hypothesized that peripheral blood mononuclear cells of keloid formers have a higher propensity to differentiate into fibrocytes and are more resistant to the effects of SAP. To test this hypothesis, plasma was isolated from peripheral blood samples of keloid (n = 10) and age/sex/race-matched control (n = 10) subjects, and SAP levels were measured by enzyme-linked immunosorbent assay. Equal numbers of peripheral blood mononuclear cells were also isolated from these samples and fibrocytes cultured in serum-free media with increasing concentrations of SAP. No difference in plasma SAP levels was found between keloid and control subjects. In the absence of SAP, keloid patients (n = 7) had almost 20 times more fibrocytes than controls (n = 7) in culture (median: 1,087 cells vs. 60 cells; p < 0.01). SAP inhibited the differentiation of keloid fibrocytes in vitro, although a higher concentration of SAP was needed when compared with controls (20 μg/mL keloid vs. 5 μg/mL control). Fibrocytes may contribute to the pathogenesis of keloids, and SAP has potential as a therapeutic agent in the prevention of these lesions.

Ancillary