Upregulation of HLA-G in JEG-3 cells by dexamethasone and hydrocortisone

Abstract

Various reports suggest that HLA-G molecule plays an important role in feto-maternal interface, protecting the allogenic fetus from maternal immune attack. It is shown that steroid hormones may upregulate the HLA-G gene expression. In the present study, we have made an attempt to upregulate the HLA-G gene expression in a HLA-G(+ve) cell line (JEG-3) by using two glucocorticoids drugs, i.e., dexamethasone and hydrocortisone. Choriocarcinoma JEG-3 (HLA-G(+ve)), JAR (HLA-G(-ve)) and erythroleukemia K-562 (HLA-G(-ve)) cell lines were obtained from American Type Culture Collection. These cell lines were treated with glucocorticoids (dexamethasone and hydrocortisone). HLA-G gene transcription was determined by standard and real-time RT-PCR analysis, and protein expression was evaluated by both flow cytometry and Western blotting. Dose-dependent increase in HLA-G mRNA and protein expression was observed in HLA-G(+ve) JEG-3 cells, while no expression was recorded in JAR and K-562 (HLA-G(-ve)) cell lines. We were able to upregulate HLA-G expression only in HLA-G(+ve) cell line. On the basis of our results, we hypothesize that the HLA-G gene expression can be upregulated only when the cell lines/cells have the basal expression and not in the cells that totally lack its expression. We have further hypothesized that these drugs may be used only in those women with recurrent miscarriages who show minimum basal expression level of HLA-G.