Understanding cornea homeostasis and wound healing using a novel model of stem cell deficiency in Xenopus

Mohd Tayyab Adil, Claire M. Simons, Surabhi Sonam, Jonathan J. Henry

Research output: Contribution to journalArticlepeer-review


Limbal Stem Cell Deficiency (LSCD) is a painful and debilitating disease that results from damage or loss of the Corneal Epithelial Stem Cells (CESCs). Therapies have been developed to treat LSCD by utilizing epithelial stem cell transplants. However, effective repair and recovery depends on many factors, such as the source and concentration of donor stem cells, and the proper conditions to support these transplanted cells. We do not yet fully understand how CESCs heal wounds or how transplanted CESCs are able to restore transparency in LSCD patients. A major hurdle has been the lack of vertebrate models to study CESCs. Here we utilized a short treatment with Psoralen AMT (a DNA cross-linker), immediately followed by UV treatment (PUV treatment), to establish a novel frog model that recapitulates the characteristics of cornea stem cell deficiency, such as pigment cell invasion from the periphery, corneal opacity, and neovascularization. These PUV treated whole corneas do not regain transparency. Moreover, PUV treatment leads to appearance of the Tcf7l2 labeled subset of apical skin cells in the cornea region. PUV treatment also results in increased cell death, immediately following treatment, with pyknosis as a primary mechanism. Furthermore, we show that PUV treatment causes depletion of p63 expressing basal epithelial cells, and can stimulate mitosis in the remaining cells in the cornea region. To study the response of CESCs, we created localized PUV damage by focusing the UV radiation on one half of the cornea. These cases initially develop localized stem cell deficiency characteristics on the treated side. The localized PUV treatment is also capable of stimulating some mitosis in the untreated (control) half of those corneas. Unlike the whole treated corneas, the treated half is ultimately able to recover and corneal transparency is restored. Our study provides insight into the response of cornea cells following stem cell depletion, and establishes Xenopus as a suitable model for studying CESCs, stem cell deficiency, and other cornea diseases. This model will also be valuable for understanding the nature of transplanted CESCs, which will lead to progress in the development of therapeutics for LSCD.

Original languageEnglish (US)
Article number107767
JournalExperimental Eye Research
StatePublished - Oct 2019


  • Cornea
  • Cornea epithelial stem cells
  • Cornea homeostasis
  • Cornea wound healing
  • Disease model
  • Psoralen-UVA
  • Stem cell deficiency
  • Xenopus

ASJC Scopus subject areas

  • Ophthalmology
  • Sensory Systems
  • Cellular and Molecular Neuroscience


Dive into the research topics of 'Understanding cornea homeostasis and wound healing using a novel model of stem cell deficiency in Xenopus'. Together they form a unique fingerprint.

Cite this