The Effects of Growth Factors on the Contractility of Muller Cells

ABSTRACT

PURPOSE: To assess the ability of retinal Muller cells that are to generate tractional forces during culture and to evaluate their responsiveness to contraction-stimulating growth factors. METHODS: After being dissociated from porcine retina, Muller cells were cultured, and identified by immunocytochemistry. The cells were applied to the collagen gel, and changes in the thickness of the collagen layer over time were measured. Then these values were used to estimate Muller cell's contractility indirectly. Each of the applications was classified by an initial cell population and added IGF-I and PDGF concentrations. RESULTS: The contraction rate of collagen at 24 hours into incubation differed significantly between the cell groups, with group 1 having a ratio of 5.08 +/- 0.81, group 2; 7.96 +/- 0.44, group 3; 21.46 +/- 0.86, and group 4; 28.36 +/- 1.64% (p=0.000). The contraction rate of the IGF-treated groups and the PDGF-treated groups are increased by their concentrations (P<0.05), and the contraction rate of the IGF-treated groups was higher than the PDGF-treated groups at all concentration (P<0.05). CONCLUSIONS: As the cell number and concentration of growth factors were increased, the contractility of Muller cells was elevated. The development of neutralizing antibody to IGF-I and PDGF can be one of the ways for prevention of proliferative vitreoretinopathy clinically.