Fibrocontractive Müller cell phenotypes in proliferative diabetic retinopathy

Clyde Guidry1, Jeffery L King, John O Mason

  • 1Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, Alabama 352994, USA. cguidry@uab.edu

Abstract

Insights

Müller cells in the eye can transform into fibrocontractive cells, contributing to proliferative diabetic retinopathy. This transformation occurs independently of glucose levels, suggesting Müller cells are a key source of these disease-driving cells.

Area of Science:

  • Ophthalmology
  • Cell Biology
  • Diabetic Retinopathy Research

Background:

  • Proliferative diabetic retinopathy (PDR) is a leading cause of vision loss.
  • Fibrocontractive membranes in PDR exert tractional forces, leading to retinal detachment.
  • The cellular origin of these fibrocontractive cells remains incompletely understood.

Purpose of the Study:

  • To investigate Müller cells as a potential source of fibrocontractive cells in PDR.
  • To characterize phenotypic changes in Müller cells associated with fibrocontraction.

Main Methods:

  • Porcine Müller cells were cultured and analyzed for glial fibrillary acidic protein (GFAP), vimentin, glutamine synthetase, and alpha smooth muscle actin (alphaSMA) expression.
  • Immunofluorescence and Western blotting were used to assess protein expression.
  • Diabetic epiretinal tissues were examined for Müller cell markers.

Main Results:

  • Müller cells in culture exhibited a loss of glutamine synthetase and GFAP, with increased alphaSMA expression, adopting a fibroblast-like morphology.
  • These phenotypic changes occurred regardless of high- or low-glucose culture conditions.
  • Diabetic epiretinal membranes contained Müller cells showing similar changes, including increased alphaSMA and loss of specific markers, correlating with a fibrocontractive phenotype.

Conclusions:

  • Müller cells present in diabetic epiretinal tissues undergo phenotypic changes similar to those observed in culture.
  • These changes indicate that Müller cells can transform into cells capable of generating tractional forces.
  • Müller cells are identified as a significant source of fibrocontractive cells in proliferative diabetic retinopathy.