Expression of HLA-G in the skin of patients with pemphigus vulgaris.

Studies on HLA-G, a nonpolymorphic antigen of non-classical HLA class I, is of basic and clinical significance. In the present study, the expression of HLA-G proteins in the human skin tissue sections of normal and autoimmune pemphigus vulgaris (PV) individuals were investigated using monoclonal antibodies. The antibodies recognized both membrane-bound and soluble isoforms of HLA-G. RT-PCR was performed to assess the patterns of HLA-G mRNA transcripts in the epidermal cells of PV and normal subjects. HLA-G expression could only be detected at transcriptional level in normal skin tissues. However cells derived from PV subjects expressed detectable HLA-G molecules at both transcriptional and translational levels. In addition, the RT-PCR patterns of HLA-G amplification revealed a reduction in HLA-G2 and an increase in HLA-G1 transcripts in epidermal cells of PV patients as compared to normal cells. These observations further support suggestions in the literature regarding the role of HLA-G in induction of tolerance in autoimmune individuals.