Anatomical location and culture of equine corneal epithelial stem cells

Abstract

Objective To identify morphologically the locations of equine corneal epithelial stem cells (CESCs) and to culture these cells. Animals studied We studied the eyes of 12 adult thoroughbred horses. Procedures Eye tissues were immunostained for two positive stem cell markers (p63, CK14) and one negative marker (CK3) to identify the locations of CESCs, so we could compare their immunostaining patterns with those of human stem cells previously reported. We compared the proliferation rates and morphological features of epithelial cells isolated from the corneal limbus and central cornea.Results Undifferentiated cells expressing the same immunostaining pattern as human CESCs were present in the equine corneal limbus. Cultured epithelial cells isolated from the limbus expressed the same immunostaining pattern that CESCs show histologically, but cells isolated from the central cornea did not proliferate and could not be evaluated. Conclusions Equine CESCs were localized in the epithelial basal layer of the corneal limbus, where melanocytes reside. They could be cultured without loss of their undifferentiated nature. When collecting such stem cells, it may be useful to harvest and culture corneal epithelial tissues in the limbus where melanocytes serve as an indicator of the collecting area.

Bilateral corneal dermoids and eyelid malformation in a colt – a case report

“…Interestingly, the periphery of the keratectomy sites underwent conjunctivalization, so ultimately the ventro-temporal limbus was covered with conjunctiva. Equine corneal epithelial stem cells (CESCs) were isolated at the corneal limbus and had the same immunostaining pattern as human CESCs (Moriyama et al 2014). These equine CESCs were localized in the epithelial basal layer of the corneal limbus, where melanocytes reside.…”

Mini-Review: Limbal Stem Cells Deficiency in Companion Animals: Time to Give Something Back?

“…It is possible similar structures might be occasionally visible with the use of a hand-held slit lamp biomicroscope in some veterinary patients although there are no reports presenting solid evidence for or against this finding. One study in equines suggests the palisades are not visible in horses (Moriyama H et al 2014). Palisades and niches have been described in mice and pigs but the authors did not indicate if they could be directly observed with slit lamp biomicroscopy (Notara et al 2011, Luesma MJ et al 2013.…”

“…However, the authors did not include healthy controls to allow for comparisons of limbal microanatomy. A recent study in equines reported the localization of LESC in the equine limbus through immunohistochemistry although microstructural studies of the horse limbus were not included (Moriyama H et al 2014).…”

“…A recent study in equines attempted the first localization of LESCs in the horse limbus through immunohistochemical cell identification using p63, cytokeratin 14 and cytokeratin 3, and it reported the successful culture of these putative cells (Moriyama H et al 2014). The study did not report the exact limbal localization of the LESCs other than they were located in areas where the limbus was pigmented.…”

Isolation and Cryopreservation of Animal Mesenchymal Stromal Cells

“…Nevertheless, more recent studies have identiied MSCs with similar properties in almost all mammalian tissues such as skeletal muscle [24,25], tendon [26], skin [27,28], adipose tissue [29], periosteum [30], synovial membrane [31], dental pulp [32], peripheral blood [33], umbilical cord blood [34], amniotic luids [35], and cornea [36].…”