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Home / Equine Research Bank / Vet Surg / Equine exuberant granulation tissue and human keloids: a com...
Veterinary surgery : VS2013; 42(7); 783-789; doi: 10.1111/j.1532-950X.2013.12055.x

Equine exuberant granulation tissue and human keloids: a comparative histopathologic study.

Abstract: To compare histopathologic features of a fibroproliferative disorder in horses (exuberant granulation tissue-EGT) and people (keloid). Methods: Archival tissue samples of EGT (n = 8) and keloid (12). Methods: After automated hematoxylin and eosin, histochemical (Gomori trichrome, Verhoeff-van Gieson elastin) and immunohistochemical (vimentin, α-smooth muscle actin, CD34, CD68, CD117) stainings, tissue sections were evaluated using a semi-quantitative grading scale for presence or absence of ulceration, keloidal collagen, myofibroblasts, and elastic fibers as well as degree of inflammation, fibrosis, vascularity, and orientation of collagen fibers. Results: Superficial dermis and deep dermis of both horses and people had increased numbers of haphazardly oriented thickened collagen fibers; however, only keloids contained "keloidal" collagen. Fibroblast numbers were markedly increased in both groups but only EGT had myofibroblasts. Minimal vascularity was observed in the deep dermis of both groups. The superficial dermis in EGT was characterized by small vessels within immature granulation tissue. Macrophages and mast cells were infrequently found in both groups but polymorphonuclear cells were markedly increased in EGT. Conclusions: Humans and horses are the only mammals known to naturally develop excessive granulation during wound healing; however, similarities and differences between fibroblast populations and associated collagen have not been reported. Inflammatory response may contribute to observed differences in the cellular populations, with EGT possessing markedly increased myofibroblasts, small vessels, and acute inflammatory cells compared with keloids. Further work is warranted to develop common treatment strategies for these fibroproliferative conditions.
© Copyright 2013 by The American College of Veterinary Surgeons.
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Publication Date: 2013-09-09 PubMed ID: 24015864DOI: 10.1111/j.1532-950X.2013.12055.xGoogle Scholar: Lookup
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  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research paper compares the histopathologic features of a fibroproliferative disorder in horses (exuberant granulation tissue-EGT) and humans (keloids), noting the similarities and differences, and suggesting the need for further research to develop common treatment strategies for these conditions.

Research Methodology

  • The study uses archival tissue samples of EGT from 8 horses and keloid from 12 humans.
  • These tissue sections underwent automated hematoxylin and eosin staining, a common procedure used to highlight structures in biological tissues for viewing under a microscope.
  • Additionally, histopathological examination was carried out using Gomori trichrome, Verhoeff-van Gieson elastin, and immunohistochemical stainings.
  • The tissue samples were then evaluated using a semi-quantitative grading scale, looking for the presence or absence of various factors, such as ulceration, myofibroblasts, elastic fibers, and inflammation among others.

Findings

  • The study discovered that both superficial and deep dermis in both horses and humans have increased numbers of haphazardly oriented thickened collagen fibers. Nonetheless, only keloids were found to contain “keloidal” collagen.
  • There was a marked increase in fibroblasts (a type of cell that synthesizes the extracellular matrix and collagen) in both groups, but only EGT had myofibroblasts.
  • There was minimal vascularity (presence of blood vessels) observed in the deep dermis of both groups, but the superficial dermis in EGT was characterized by small vessels within the immature granulation tissue.
  • Different types of immune cells such as macrophages and mast cells were infrequently found in both groups. However, polymorphonuclear cells (a type of immune cell) were markedly increased in EGT.
  • The study concludes that the inflammatory response may contribute to the observed differences in the cellular populations, with EGT showing more acute inflammatory cells compared to keloids.

Conclusion

  • This research provides an in-depth comparative study between EGT in horses and keloids in humans—conditions marked by excessive granulation during wound healing.
  • It highlights the similarities and differences between them at a cellular level, suggesting that the pathogenesis of these conditions could be somewhat similar.
  • The paper concludes with the recommendation that more investigation is needed into these fibroproliferative conditions to develop common treatment strategies.

Cite This Article

APA
Theoret CL, Olutoye OO, Parnell LK, Hicks J. (2013). Equine exuberant granulation tissue and human keloids: a comparative histopathologic study. Vet Surg, 42(7), 783-789. https://doi.org/10.1111/j.1532-950X.2013.12055.x

Publication

Veterinary surgery : VS
ISSN: 1532-950X
NlmUniqueID: 8113214
Country: United States
Language: English
Volume: 42
Issue: 7
Pages: 783-789

Researcher Affiliations

Theoret, Christine L
  • Université de Montréal, Saint-Hyacinthe, Québec, Canada.
Olutoye, Oluyinka O
    Parnell, Laura K S
      Hicks, John

        MeSH Terms

        • Animals
        • Cicatrix, Hypertrophic / pathology
        • Cicatrix, Hypertrophic / veterinary
        • Dermis
        • Epidermis
        • Fibrosis
        • Gene Expression Regulation
        • Horse Diseases / pathology
        • Horses
        • Humans
        • Keloid / pathology
        • Wound Healing

        Citations

        This article has been cited 22 times.
        1. Partusch L, Rutland CS, Martens A, Du Cheyne C, De Spiegelaere W, Michler JK. Collagen composition in equine exuberant granulation tissue reflects tissue immaturity. PLoS One 2025;20(11):e0335179.
          doi: 10.1371/journal.pone.0335179pubmed: 41196884google scholar: lookup
        2. Apolonio EVP, Gobbo LL, Woiblet NG, Dinau FC, Pyles MS, Ferrari LC, de Moura Alonso J, Alves ALG. Vascular hamartoma in horse limbs: presentation, diagnosis, and treatment of two case studies. Vet Res Commun 2024 Nov 15;49(1):8.
          doi: 10.1007/s11259-024-10601-ypubmed: 39546070google scholar: lookup
        3. Mihele DM, Nistor PA, Bruma G, Mitran CI, Mitran MI, Condrat CE, Tovaru M, Tampa M, Georgescu SR. Mast Cell Activation Syndrome Update-A Dermatological Perspective. J Pers Med 2023 Jul 10;13(7).
          doi: 10.3390/jpm13071116pubmed: 37511729google scholar: lookup
        4. Du Cheyne C, Martens A, De Spiegelaere W. High Numbers of CD163-Positive Macrophages in the Fibrotic Region of Exuberant Granulation Tissue in Horses. Animals (Basel) 2021 Sep 18;11(9).
          doi: 10.3390/ani11092728pubmed: 34573694google scholar: lookup
        5. Cequier A, Sanz C, Rodellar C, Barrachina L. The Usefulness of Mesenchymal Stem Cells beyond the Musculoskeletal System in Horses. Animals (Basel) 2021 Mar 25;11(4).
          doi: 10.3390/ani11040931pubmed: 33805967google scholar: lookup
        6. Wilgus TA, Ud-Din S, Bayat A. A Review of the Evidence for and against a Role for Mast Cells in Cutaneous Scarring and Fibrosis. Int J Mol Sci 2020 Dec 18;21(24).
          doi: 10.3390/ijms21249673pubmed: 33353063google scholar: lookup
        7. Wilgus TA. Inflammation as an orchestrator of cutaneous scar formation: a review of the literature. Plast Aesthet Res 2020;7.
          doi: 10.20517/2347-9264.2020.150pubmed: 33123623google scholar: lookup
        8. Ud-Din S, Wilgus TA, Bayat A. Mast Cells in Skin Scarring: A Review of Animal and Human Research. Front Immunol 2020;11:552205.
          doi: 10.3389/fimmu.2020.552205pubmed: 33117341google scholar: lookup
        9. Wilmink JM, Ladefoged S, Jongbloets A, Vernooij JCM. The evaluation of the effect of probiotics on the healing of equine distal limb wounds. PLoS One 2020;15(7):e0236761.
          doi: 10.1371/journal.pone.0236761pubmed: 32726347google scholar: lookup
        10. Dubuc V, Laverty S, Richard H, Doré M, Theoret C. Development of a computer-based quantification method for immunohistochemically-stained tissues and its application to study mast cells in equine wound healing (proof of concept). BMC Vet Res 2020 Jul 2;16(1):228.
          doi: 10.1186/s12917-020-02444-xpubmed: 32616050google scholar: lookup
        11. Limandjaja GC, Niessen FB, Scheper RJ, Gibbs S. The Keloid Disorder: Heterogeneity, Histopathology, Mechanisms and Models. Front Cell Dev Biol 2020;8:360.
          doi: 10.3389/fcell.2020.00360pubmed: 32528951google scholar: lookup
        12. Mund SJK, Kawamura E, Awang-Junaidi AH, Campbell J, Wobeser B, MacPhee DJ, Honaramooz A, Barber S. Homing and Engraftment of Intravenously Administered Equine Cord Blood-Derived Multipotent Mesenchymal Stromal Cells to Surgically Created Cutaneous Wound in Horses: A Pilot Project. Cells 2020 May 8;9(5).
          doi: 10.3390/cells9051162pubmed: 32397125google scholar: lookup
        13. Ericson C, Stenfeldt P, Hardeman A, Jacobson I. The Effect of Kinesiotape on Flexion-Extension of the Thoracolumbar Back in Horses at Trot. Animals (Basel) 2020 Feb 13;10(2).
          doi: 10.3390/ani10020301pubmed: 32069962google scholar: lookup
        14. Supp DM. Animal Models for Studies of Keloid Scarring. Adv Wound Care (New Rochelle) 2019 Feb 1;8(2):77-89.
          doi: 10.1089/wound.2018.0828pubmed: 31832272google scholar: lookup
        15. Wise LM, Bodaan CJ, Stuart GS, Real NC, Lateef Z, Mercer AA, Riley CB, Theoret CL. Treatment of limb wounds of horses with orf virus IL-10 and VEGF-E accelerates resolution of exuberant granulation tissue, but does not prevent its development. PLoS One 2018;13(5):e0197223.
          doi: 10.1371/journal.pone.0197223pubmed: 29763436google scholar: lookup
        16. Textor JA, Clark KC, Walker NJ, Aristizobal FA, Kol A, LeJeune SS, Bledsoe A, Davidyan A, Gray SN, Bohannon-Worsley LK, Woolard KD, Borjesson DL. Allogeneic Stem Cells Alter Gene Expression and Improve Healing of Distal Limb Wounds in Horses. Stem Cells Transl Med 2018 Jan;7(1):98-108.
          doi: 10.1002/sctm.17-0071pubmed: 29063737google scholar: lookup
        17. Martano M, Corteggio A, Restucci B, De Biase ME, Borzacchiello G, Maiolino P. Extracellular matrix remodeling in equine sarcoid: an immunohistochemical and molecular study. BMC Vet Res 2016 Feb 2;12:24.
          doi: 10.1186/s12917-016-0648-1pubmed: 26838095google scholar: lookup
        18. Marttala J, Andrews JP, Rosenbloom J, Uitto J. Keloids: Animal models and pathologic equivalents to study tissue fibrosis. Matrix Biol 2016 Apr;51:47-54.
          doi: 10.1016/j.matbio.2016.01.014pubmed: 26827712google scholar: lookup
        19. Wells A, Nuschke A, Yates CC. Skin tissue repair: Matrix microenvironmental influences. Matrix Biol 2016 Jan;49:25-36.
          doi: 10.1016/j.matbio.2015.08.001pubmed: 26278492google scholar: lookup
        20. de Souza MV, Silva MB, Pinto Jde O, Lima MB, Crepaldi J, Lopes GF, dos Santos HB, Ribeiro RI, Thomé RG. Immunohistochemical Expression of Collagens in the Skin of Horses Treated with Leukocyte-Poor Platelet-Rich Plasma. Biomed Res Int 2015;2015:893485.
          doi: 10.1155/2015/893485pubmed: 26236743google scholar: lookup
        21. Bussche L, Harman RM, Syracuse BA, Plante EL, Lu YC, Curtis TM, Ma M, Van de Walle GR. Microencapsulated equine mesenchymal stromal cells promote cutaneous wound healing in vitro. Stem Cell Res Ther 2015 Apr 11;6(1):66.
          doi: 10.1186/s13287-015-0037-xpubmed: 25889766google scholar: lookup
        22. Muthusubramaniam L, Zaitseva T, Paukshto M, Martin G, Desai T. Effect of collagen nanotopography on keloid fibroblast proliferation and matrix synthesis: implications for dermal wound healing. Tissue Eng Part A 2014 Oct;20(19-20):2728-36.
          doi: 10.1089/ten.TEA.2013.0539pubmed: 24724556google scholar: lookup
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