Abstract
Purpose: :
Hyaluronan (hyaluronic acid: HA) affects certain effects on various types of cells and regulates cellular functions, including cell proliferation, migration etc. HA is produced from component cells of proliferative membrane in vitreo–retinal diseases, and may be involved in the pathogenesis of those diseases (Jpn J Ophthalmol 47 557, 2003). In this study we established the cell line of hyalocytes derived from porcine eyes and investigated the molecular mechanism of HA production by cytokine stimuli.
Material and Methods: :
Hyalocytes were separated from the vitreous of the 2–years–old porcine eyes, and cultured in DMEM with 10% fetal bovine serum. To establish the cell line, simian virus 40 large T antigen gene was transferred into the primary culture cells, and some monoclonal cell lines were separated. As the markers of cells, the expression of glial fibrillary acidic protein (GFAP) and S–100 protein was investigated immunocytochemically. The effect of transforming growth factor–ß2 (TGF–ß2) and/or platelet–derived growth factor–BB (PDGF–BB) on the HAS expression at mRNA level by RT–PCR and HA production was measured by ELISA.
Results: :
Two porcine cell lines were generated and expressed GFAP and S–100 protein. Stimulation with TGF–ß2 or PDGF–BB induced a marked increase in the expression level of HAS2 mRNA, and induced HA production. TGF–ß2 stimulated HAS2 expression through the signal transduction pathway including Smad2,3,4.
Conclusions: :
The production of HA was induced from the generated porcine hyalocyte cell lines under the stimulation of TGF–ß2 or PDGF–BB, which may be related to the pathogenesis of proliferative membrane formation in proliferative vitreo–retinal diseases.
Keywords: vitreous • signal transduction • growth factors/growth factor receptors