Abstract
Purpose::
To generate a comprehensive profile of gene expression from fresh surgical lens epithelium samples obtained by capsulorrhexis from individual human donors.
Methods::
Surgical specimens were obtained from four donors (ages 78, 79, 80 and 83) with age-related cataracts and fixed immediately in RNA later (Ambion). Between 50 and 174 nanograms of total RNA per individual sample was isolated using the RNeasy mini kit (Qiagen). RNA concentration and quality were measured using the Agilent 2100 Bioanalyzer. 15 to 40 nanograms of RNA per tissue were independently amplified using the Ovation Biotin RNA amplification and Labeling System (NuGen Technologies) and hybridized to Affymetrix U133 plus 2.0 arrays containing over 54,675 probe sets representing 47,000 transcripts.
Results::
Each individual specimen provided RNA of sufficient quantity for hybridization of the Affymetrix U133 plus 2.0 arrays. Array analysis of 15 to 40 nanograms of RNA identified between 21,904 and 26,502 gene transcripts in the four samples analyzed. Notwithstanding individual variability, all four samples provided similar patterns of gene expression. The genes more highly expressed in all samples included several crystallins (alpha B, beta B2, and gamma S), metabolic enzymes (LDHA, enolase A and aldehyde dehydrogenase 1), amyloid beta A4 precursor and amyloid beta A4 precursor -like protein 2 as well as genes that could potentially influence other tissues in the eye such as prostaglandin D2 synthase, TIMP2 and TIMP3.
Conclusions::
Genome-wide microarray analysis of the gene expression of lens epithelium from anterior capsulotomy specimens should serve as a valuable tool for the comprehensive analysis of genes involved in relevant physiologic functions of lens epithelial cells such as protection against oxidative damage and altered protein degradation, as well as of genes expressed by the lens epithelium that may influence surrounding ocular tissues such as growth factors and prostaglandins.
Keywords: gene microarray • cataract