Primary cultured human thymic epithelial cells express both membrane-bound and soluble HLA-G translated products.

This report demonstrates that both membrane-bound and soluble HLA-G isoforms are present in primary cultured human thymic epithelial cells (TEC). HLA-G transcriptional isoforms have been detected by RT-PCR, using different sets of HLA-G specific primers. A flow cytometry analysis, using two anti-HLA-G mAbs, namely 87G and BFL.1, revealed the presence of HLA-G translated products at the cell surface of a subpopulation of TEC. Finally, it was shown that HLA-G soluble forms were secreted in TEC culture supernatant, using a sandwich ELISA with BFL.1 and W6/32 mAbs. These results confirm and extent those previously described showing that HLA-G expressing cells were detectable by immunohistochemistry in thymic medullary epithelial cells.