Gene expression profile in corneal neovascularization identified by immunology related macroarray.

PURPOSE: To identify differentially expressed genes in corneal neovascularization using cDNA macroarray.

METHODS

Mechanical denudation of corneal and limbal epithelium was performed to induce corneal vascularization in mice. Corneas were harvested 4 days after operation. Total RNA was isolated from both normal and vascularized corneas and used for the synthesis of cDNA probes. 32P labeled exponential cDNA probes were hybridized to mouse cDNA immunology arrays. To validate the gene expression patterns revealed by the cDNA expression array analysis, semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) and statistical analysis were performed to compare the normal and vascularized corneal samples.

RESULTS

Of 545 immunology related genes on the arrays, 6 genes were upregulated and 1 gene was downregulated in the vascularized corneas compared with the normal corneas. Semi-quantitative RT-PCR was performed on the 6 genes selected in the arrays study, and showed that calreticulin (calregulin), apolipoprotein E, HSP84 (HSP90beta), and pleiotrophin were upregulated while interferon regulatory factor-1 was downregulated in the vascularized corneas compared with the normal corneas. These genes possess a number of biological functions including molecular chaperon, growth factor, and transcriptional factors.

CONCLUSIONS

The differentially expressed genes newly identified in the context of corneal neovascularization represent novel candidate factors for further functional studies of the mechanisms of corneal neovascularization. Our data may provide new insight into the biological process of inflammation induced corneal neovascularization.