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Normal microscopic anatomy of equine body and limb skin: A morphological and immunohistochemical study.

Abstract: Information on microscopic anatomy of equine skin is sparse. In horses, limb wounds often become chronic and/or non-healing whereas body wounds heal normally. These dissimilarities in healing patterns might be a product of different phenotypic characteristics of body and limb skin. The objective of this study was to investigate microscopic anatomy, epidermal thickness, keratinocyte proliferation and differentiation as well as the presence of mast cells in normal equine skin of body and limb. Methods: The study involved body and limb skin biopsies from six horses. Histological characteristics of the epidermis were assessed and epithelial thickness measured. Immunohistochemistry was performed to investigate epidermal differentiation patterns of cytokeratin (CK) 10, CK14, CK16, loricrin, and peroxisome proliferator-activated receptor alpha (PPAR-α), epidermal proliferation (Ki-67 immunostaining), and mast cells distribution in the skin. Results: The epidermis was significantly thicker in the limb skin compared to body skin (p<0.01). Epidermal proliferation and CK distribution did not show differences in the two anatomical areas. Loricrin presence was focally found in the spinous layer in four out of six limb skin samples but not in body skin samples. Tryptase positive mast cells were detected in the dermis and their density (cell/mm2) was not different between body and limb. Conclusions: Here we report for the first time about the normal distribution of CK10, CK14, CK16, PPAR-α, and loricrin in equine limb and body skin as well as about epidermal proliferation rate and mast cell count. It will be relevant to investigate the distribution of the investigated epithelial differentiation markers and the role of mast cells during equine wound healing and/or other skin diseases.
Publication Date: 2018-05-03 PubMed ID: 29730469DOI: 10.1016/j.aanat.2018.03.010Google Scholar: Lookup
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  • Journal Article

Summary

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The research article details an examination of the microscopic anatomy of skin in horses, comparing the skin on their bodies and limbs. The study investigates differentiation in the epidermis and the presence of mast cells, striving to understand why wounds on horse limbs tend to become chronic while body wounds heal normally.

Objective and Methodology

  • The purpose of this research was to explore the microscopic anatomy, epidermal thickness, keratinocyte proliferation, and presence of mast cells in normal horse skin on the body and limbs. The potential existence of differing phenotypic characteristics between body and limb skin could explain the varying healing patterns of horse wounds in these areas.
  • To gather data, skin biopsies were taken from both body and limb areas of six horses. The histological attributes of the epidermis were assessed and the thickness of this layer was measured.
  • To further understand the patterns of epidermal differentiation, immunohistochemistry was performed on the skin samples. This process evaluated the distribution of cytokeratins (CK) 10, CK14, and CK16, loricrin, and peroxisome proliferator-activated receptor alpha (PPAR-α).
  • The researchers also checked for epidermal proliferation rates using Ki-67 immunostaining, and evaluated the distribution of mast cells in the skin.

Results

  • The analysis showed that the epidermis of the limb skin was significantly thicker than that of body skin. However, the epidermal proliferation and the distribution of CK showed no significant differences between the two anatomic areas.
  • Loricrin was found in the spinous layer of limb skin samples from four out of six horses, but not in any of the body skin samples.
  • Tryptase-positive mast cells were also found in the skin’s dermis, but the density of these cells did not vary between the body and limb skin.

Conclusion

  • This study reports first-time findings on the standard distribution of cytokeratins (CK10, CK14, CK16), PPAR-α, and loricrin in horse limb and body skin. It also provides information on rates of epidermal proliferation and mast cell counts.
  • Identifying these differences contributes to a better understanding of the healing process of equine wounds in these areas. This knowledge could lead to more effective treatments for skin diseases or improving recovery from injuries.

Cite This Article

APA
Jørgensen E, Lazzarini G, Pirone A, Jacobsen S, Miragliotta V. (2018). Normal microscopic anatomy of equine body and limb skin: A morphological and immunohistochemical study. Ann Anat, 218, 205-212. https://doi.org/10.1016/j.aanat.2018.03.010

Publication

ISSN: 1618-0402
NlmUniqueID: 100963897
Country: Germany
Language: English
Volume: 218
Pages: 205-212

Researcher Affiliations

Jørgensen, Elin
  • Department of Veterinary Clinical Sciences, University of Copenhagen, Højbakkegaard Alle 5, DK-2630 Taastrup, Denmark.
Lazzarini, Giulia
  • Department of Veterinary Sciences, University of Pisa, viale delle Piagge 2, 56124 Pisa, Italy.
Pirone, Andrea
  • Department of Veterinary Sciences, University of Pisa, viale delle Piagge 2, 56124 Pisa, Italy.
Jacobsen, Stine
  • Department of Veterinary Clinical Sciences, University of Copenhagen, Højbakkegaard Alle 5, DK-2630 Taastrup, Denmark.
Miragliotta, Vincenzo
  • Department of Veterinary Sciences, University of Pisa, viale delle Piagge 2, 56124 Pisa, Italy. Electronic address: vincenzo.miragliotta@unipi.it.

MeSH Terms

  • Animals
  • Cell Differentiation
  • Cell Proliferation
  • Dermis / cytology
  • Epidermal Cells
  • Epidermis / anatomy & histology
  • Epidermis / ultrastructure
  • Extremities / anatomy & histology
  • Horses / anatomy & histology
  • Immunohistochemistry
  • Keratinocytes / ultrastructure
  • Keratins / metabolism
  • Male
  • Mast Cells / ultrastructure
  • Membrane Proteins / metabolism
  • Skin / anatomy & histology
  • Skin / cytology
  • Skin / ultrastructure

Citations

This article has been cited 10 times.
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