Acta Pharmacologica Sinica (2009) 30: 1625–1633; doi: 10.1038/aps.2009.154; published online 16 Nov 2009

Aim:To investigate the effect of lentivirus-mediated integrin-linked kinase (ILK) RNA interference (RNAi) on human retinal Müller cells transdifferentiation into contractile myofibroblasts.

Methods: A lentiviral vector expressing ILK-specific shRNA was constructed and introduced into cultured retinal Müller cells. Silencing of the ILK gene was identified by real time RT-PCR and Western blot. The Müller cell phenotype change was confirmed by immunodetection of  α-smooth muscle actin (α-SMA) stress fiber formation. The generation of tractional force was assessed using a tissue culture assay with cells incubated in three-dimensional collagen gels; cell migration was determined by the Boyden chamber method, using 10% FBS as a chemotactic factor.

Results: Significant decreases in ILK mRNA and protein expression were detected in Müller cells carrying lentiviral ILK-shRNA vector. Cells treated with anti-ILK siRNA showed less α-SMA stress fiber formation under hypoxic conditions or cell subcultivation. Lentiviral ILK-shRNA vector transfection also significantly reduced cell migration and cell-mediated gel contraction. 

Conclusion: Lentivirus-mediated ILK RNAi decreased cell migration and contractile force generation by inhibiting α-SMA stress fiber formation in human retinal Müller cells. This tool might be useful to treat ocular fibroproliferative diseases associated with transdifferentiated Müller cells.

Keywords: integrin linked kinase; RNA interference; lentivirus; retinal; α-SMA