Changes of the HLA–G expression in the corneal and conjunctival epithelium cultivated on the amniotic membrane

Abstract

Abstract: : Purpose: To analyze the influence of amniotic membrane on HLA–G expression in the corneal and conjunctival epthelium Methods: Gene expression profile of the conjunctival epithelium cultured on amniotic membrane was studied by microarray. HLA–G expression was identified by RT–PCR, and the level of HLA–G mRNA expression in the corneal and conjunctival epithelium was quantified by real–time PCR. Human corneal epithelial cell line (HCEC), primary culture of the conjunctival and corneal epithelial cells and human corneal epithelial cells obtained from donor eyes were used. In order to study the influence of amniotic membrane, the cells were cultivated on amniotic membrane or in the medium with sonicated amniotic membrane. Results: Microarray analysis revealed increased expression of the HLA–G genes ( 2.6 fold ) in the conjunctival epithelium, with decreased expression of other HLA genes (approximately half) when cultivated on the amniotic membrane compared with control. This change in the HLA–G expression was confirmed by real–time PCR, which showed increased by 2 fold in the conjunctival epithelium cultured on amniotic membrane. Expression of HLA–G in the cornea epithelium cultivated on the amniotic membrane did not change significantly compared with that cultivated on a plastic dish, however, it was increased with an addition of IFN–g. Expression of HLA–G in the cornea epithelium did not change significantly with the addition of sonicated amniotic membrane and IFN–g in culture medium. Conclusions: Expression of HLA–G mRNA in the conjunctival epithelium was increased when cultivated on the amniotic membrane. IFN–g increased the expression of HLA–G in both the conjunctival and corneal epithelium. The results indicate that changes in HLA–G expression may be attributed for the suppression of immunological and inflammatory responses following amniotic membrane transplantation . Supported by a grant of the Ministry of Health and Walfare. (Saisei, H15–13).

Keywords: cornea: epithelium • gene/expression • immunomodulation/immunoregulation