Abstract
Abstract: :
Purpose: To determine whether topical application of conditioned medium (CM) from human amniotic epithelial cells (HAEC) suppresses corneal inflammation, and whether CM from HAEC contains anti-inflammatory factor and regulates cytokine gene expression in the inflamed cornea. Methods: Human amniotic epithelial tissue was mechanically peeled free from the chorion of a placenta after an informed consent. HAECs were cultured in DMEM (0.5% FCS) for 48 hours, and the supernatant was corrected as CM. Cytokine expression in the CM was assessed by ELISA. Intrastromal sutures or superficial cauterization were applied in corneas of BALB/c mice to induce corneal neovascularization (CNV) and Langerhans cells (LC) migration. These corneas received topical application of CM from HAEC or placebo 3 times a day for 2 weeks after the manipulations. Suture-induced CNV was evaluated microscopically for 8 weeks. The cauterized corneas were harvested at 2 weeks, and LC numbers were enumerated by immunofluorecent staining using confocal microscopy. Cytokine gene expression in the cauterized corneas was analyzed by RNase protection assay. Results: ELISA assay revealed that CM from HAEC contained human Interleukin-1 receptor antagonist (IL-1ra). Treatment with CM from HAEC led to a profound suppression of CNV and LC migration compared with placebo controls (p<0.05). Expression of mRNA of murine IL-1ra and murine IL-1 alpha in the cauterized corneas was markedly reduced after application of CM from HAEC in comparison with those after placebo application. Conclusion: CM from HAEC contains IL-1ra. Topical administration of CM from HAEC has significant suppressive effects on CNV and LC migration in mouse eyes. CM from HAEC can be an effective modality in reducing ocular surface inflammation.
Keywords: 435 immunomodulation/immunoregulation • 437 inflammation • 380 cytokines/chemokines