Radial keratotomy: II. Role of the myofibroblast in corneal wound contraction

R. M R Garana, Walter M Petroll, W. T. Chen, I. M. Herman, P. Barry, P. Andrews, Harrison D Cavanagh, J. V. Jester

Research output: Contribution to journalArticle

133 Scopus citations

Abstract

The cellular mechanism of corneal wound contraction after radial keratotomy (RK) was studied in a feline eye model. A total of 10 cat eyes were evaluated at various times from 0-30 days after surgery. Changes in the distribution of intracellular filamentous actin, nonmuscle myosin, α- actinin, surface membrane α5β1 integrin, and extracellular fibronectin were studied using immunofluorescence and laser confocal and electron microscopy. From day 3-7, staining for fibronectin increased along the wound margin. By day 7, keratocytes adjacent to the wound margin showed increased f-actin staining with intense staining for fibronectin compared with normal keratocytes. Myosin and α5β1 integrin expression was very weak at this time; α-actinin was not found. By day 14, fibroblasts within the wound formed f-actin microfilament bundles (stress fibers) which colocalized with fibronectin. Wound-healing fibroblasts also stained positively for α5β1 integrin, myosin, and α-actinin (the latter two were colocalized). The presence of myosin and α-actinin in the wound fibroblasts and the re- organization of f-actin into stress fibers by day 14 correlated with the development of wound contraction. A comparison of the cellular distribution of actin, myosin, and α-actinin with α5β1 integrin 14 days after injury suggested that integrin was localized along stress fiber bundles during wound contraction. The data from this study suggest that modulation of wound gape during healing of RK wounds may involve transformation of the corneal keratocyte to a myofibroblast-like cell and the subsequent formation of intracellular stress fibers composed of f-actin, nonmuscle myosin, and α- actinin. Based on the colocalization of fibronectin filaments and f-actin filaments and the unique distribution of α5β1 integrin, these findings support the hypothesis that the tension within the wound is generated by the formation of intracellular stress fibers and the interactions between stress fibers and the extracellular matrix, mediated by specific membrane receptor molecules.

Original languageEnglish (US)
Pages (from-to)3271-3282
Number of pages12
JournalInvestigative Ophthalmology and Visual Science
Volume33
Issue number12
StatePublished - Jan 1 1992

Keywords

  • actin
  • alpha- actinin
  • cornea
  • fibronectin
  • integrin
  • myofibroblast
  • myosin
  • radial keratotomy
  • refractive surgery
  • wound healing

ASJC Scopus subject areas

  • Ophthalmology
  • Sensory Systems
  • Cellular and Molecular Neuroscience

Fingerprint Dive into the research topics of 'Radial keratotomy: II. Role of the myofibroblast in corneal wound contraction'. Together they form a unique fingerprint.

  • Cite this

    Garana, R. M. R., Petroll, W. M., Chen, W. T., Herman, I. M., Barry, P., Andrews, P., Cavanagh, H. D., & Jester, J. V. (1992). Radial keratotomy: II. Role of the myofibroblast in corneal wound contraction. Investigative Ophthalmology and Visual Science, 33(12), 3271-3282.