Citation: Journal of Burn Care & Research. 36(3):e125-35, 2015 May-Jun..Journal: Journal of burn care & research : official publication of the American Burn Association.ISSN: 1559-047X.Full author list: Travis TE; Mino MJ; Moffatt LT; Mauskar NA; Prindeze NJ; Ghassemi P; Ramella-Roman JC; Jordan MH; Shupp JW.UI/PMID: 25051518.Subject(s): Animals | Antigens, CD34/me [Metabolism] | Burns/me [Metabolism] | *Burns/pa [Pathology] | Cicatrix, Hypertrophic/me [Metabolism] | *Cicatrix, Hypertrophic/pa [Pathology] | Disease Models, Animal | Fibroblasts/me [Metabolism] | *Fibroblasts/pa [Pathology] | Skin/in [Injuries] | *Skin/pa [Pathology] | Swine | Wound Healing/ph [Physiology]Institution(s): MedStar Washington Hospital CenterDepartment(s): Surgery/Burn ServicesActivity type: Journal Article.Medline article type(s): Journal Article | Research Support, N.I.H., ExtramuralOnline resources: Click here to access onlineDigital Object Identifier: http://dx.doi.org/10.1097/BCR.0000000000000097 (Click here)Abbreviated citation: J Burn Care Res. 36(3):e125-35, 2015 May-Jun.Local Holdings: Available online through MWHC library: 2006 - present, Available in print through MWHC library: 2006 - present.Abstract: The duroc pig has been described as a promising animal model for use in the study of human wound healing and scar formation. However, little is known about the presence and chronology of the fibrocyte cell population in the healing process of these animals. Wounds known to form scar were created on red duroc swine (3" x 3") with a dermatome to a total depth of either 0.06 inches or 0.09 inches. These wounds were allowed to heal completely and biopsies were done at scheduled time points during the healing process. Biopsies were formalin fixed and paraffin embedded for immunohistochemical analysis. Porcine reactive antibodies to CD-45 and procollagen-1 and a human reactive antibody to LSP-1 were used to detect the presence of fibrocytes in immunohistochemistry, an immunocytochemistry. Initial immunohistochemical studies showed evidence of a biphasic presence of fibrocytes. Pigs with 0.06 inches deep wounds showed positive staining for CD-45 and LSP-1 within highly cellular areas at days 2 and 4 after wounding. Additional animals with 0.09 inches deep wounds showed positive staining within similar areas at days 56, 70, and 113 after wounding. There was no immunohistochemical evidence of fibrocytes in skin biopsies taken at days 14, 28, or 42. Procollagen-1 staining was diffused in all samples. Cultured cells were stained for CD-45, LSP-1, and procollagen-1 by immunocytochemistry. These data confirm that fibrocytes are indeed present in this porcine model. We conclude that these cells are present after initial wounding and later during scar formation and remodeling. We believe that this is an evidence of a biphasic presence of fibrocytes, first as an acute response to skin wounding followed by later involvement in the remodeling process, prompted by continued inflammation in a deep partial thickness wound.