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Veterinary ophthalmology2021; 25(2); 153-164; doi: 10.1111/vop.12953

Therapeutic effects of equine amniotic membrane suspension on corneal re-epithelialization and haze in a modified lagomorph ex vivo wound healing model.

Abstract: To investigate the therapeutic effects of topical equine amniotic membrane (eAM) suspension following corneal wounding in a controlled experimental setting. Methods: Equine amniotic membrane was collected, gamma irradiated, homogenized for topical suspension preparation, and cryopreserved. Corneoscleral rims harvested from fresh rabbit globes were wounded via keratectomy and were maintained in an air-liquid interface ex vivo corneal culture model. Treatment groups included topical gamma irradiated eAM suspension (n = 20) and a control group (n = 20). Re-epithelialization of the wound was assessed with daily photographic evaluation of area of fluorescein uptake (mm2 ). Corneal wound haze after a 21-day period was assessed by photographic analysis of haze area (mm2 ) and pixel intensity (0-255). Histologic processing of corneal tissue was performed, and protein identification of eAM suspension using Liquid chromatography-mass spectrometry (LC-MS). Results: The average day of complete corneal re-epithelialization in controls (5.5 ± 1.1) and topically treated (5.5 ± 0.6) corneas, and rates of reduction in area of fluorescein uptake over time did not significantly differ (p = .44). The corneal wound haze was significantly reduced in mean area by approximately 52% and intensity by 57% in corneas treated with topical eAM suspension (p < .05), compared to controls 21 days following wounding. Protein analysis identified numerous proteins, specifically decorin, dermatopontin, and lumican, which have previously been documented in eAM. Conclusions: Area and intensity of corneal wound haze were significantly reduced in corneas treated with gamma irradiated eAM suspension, which may be due to previously identified therapeutic proteins which promote corneal clarity.
Publication Date: 2021-11-17 PubMed ID: 34787351DOI: 10.1111/vop.12953Google Scholar: Lookup
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  • Journal Article

Summary

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This research paper focuses on studying the therapeutic effects of using an equine amniotic membrane (eAM) suspension on wound healing in rabbit corneas in a controlled setting. The study found that applying eAM reduced corneal haze following injuries but did not significantly alter the rate at which the damage re-epithelialized.

Methods

  • The research team collected the equine amniotic membrane, subjected it to gamma irradiation, and then homogenized it to prepare a topical suspension.
  • The suspension was then cryopreserved for later use.
  • Rabbit corneoscleral rims, parts around the outer edges of the eyes, were taken from fresh globes. These globes were next wounded via keratectomy and maintained in an ex vivo corneal culture model that maintained an air-liquid interface.
  • The study formulated two groups: a test group that received the topical eAM suspension (20 members), and a control group (20 members).
  • They monitored the re-epithelialization, or the skin growth, of the wound via daily photographic evaluations.
  • After a span of 21 days, corneal wound haze was analyzed through photographic comparisons involving haze area measurements and pixel intensity analysis.
  • The researchers also carried out a histologic processing of the corneal tissue and used Liquid chromatography-mass spectrometry (LC-MS) to identify proteins in the eAM suspension.

Results

  • The researchers noticed that the average day of full corneal re-epithelialization remained the same for both the control group as well as the treated one.
  • The changes noticed in the area of fluorescein uptake over time between the two groups showed no significant difference.
  • However, the haze in the corneas treated with topical eAM suspension significantly reduced by about 52% in terms of area and likewise, the intensity of the haze decreased by around 57% when compared to the control group.
  • The protein analysis of the eAM suspension revealed the presence of proteins like decorin, dermatopontin, and lumican which are already associated with eAM.

Conclusion

  • The research concluded that treating corneas with gamma-irradiated eAM suspension significantly reduced the area and intensity of corneal wound haze.
  • This reduction could potentially be attributed to certain therapeutic proteins found in the eAM suspension that may promote corneal clarity.

Cite This Article

APA
Boss CK, Gibson DJ, Schultz G, Whitley RD, Hernandez JA, Abbott JR, Plummer CE. (2021). Therapeutic effects of equine amniotic membrane suspension on corneal re-epithelialization and haze in a modified lagomorph ex vivo wound healing model. Vet Ophthalmol, 25(2), 153-164. https://doi.org/10.1111/vop.12953

Publication

ISSN: 1463-5224
NlmUniqueID: 100887377
Country: England
Language: English
Volume: 25
Issue: 2
Pages: 153-164

Researcher Affiliations

Boss, Christine K
  • Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida, USA.
Gibson, Daniel J
  • College of Nursing, University of Alabama at Birmingham, Birmingham, Alabama, USA.
Schultz, Gregory
  • Department of Obstetrics and Gynecology, College of Medicine, University of Florida, Gainesville, Florida, USA.
Whitley, R David
  • Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida, USA.
Hernandez, Jorge A
  • Washington State University, Pullman, Washington, USA.
Abbott, Jeffrey R
  • College of Nursing, University of Alabama at Birmingham, Birmingham, Alabama, USA.
Plummer, Caryn E
  • Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida, USA.

MeSH Terms

  • Amnion
  • Animals
  • Cornea
  • Epithelium, Corneal / pathology
  • Horses
  • Lagomorpha
  • Rabbits
  • Re-Epithelialization
  • Wound Healing

Grant Funding

  • 2017-18 / University of Florida Foundation

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Citations

This article has been cited 1 times.
  1. Hisey EA, Martins BC, Donnelly CG, Cassano JM, Katzman SA, Murphy CJ, Thomasy SM, Leonard BC. Identification of putative orthologs of clinically relevant antimicrobial peptides in the equine ocular surface and amniotic membrane. Vet Ophthalmol 2023 Apr;26 Suppl 1(Suppl 1):125-133.
    doi: 10.1111/vop.13042pubmed: 36478371google scholar: lookup