The results show significant increases in proportions of CD56+ T cells in relation to CMV infection in renal transplant patients and suggest that these cells have a cytotoxic function against CMV-infected cells.

Background: HLA-G is an immunosuppressive molecule with a potential role in allograft acceptance. Methods: Expression of HLA-G on leucocyte subpopulations was studied in a group of 21 renal transplant patients immediately prior to and 2 months post-transplantation. Results: Significant increases in proportions of total HLA-G+CD4+ T cells were seen (0.5+/-0.1% to 7.9+/-3.2%; p<0.01) and also for CD45RA+, CD45RO+ and CD69+ subsets. Increases in proportions of HLA-G+ cells were also seen in CD8+ T cells and their subsets, CD56+ T cells, B cells, NK cells and monocytes, and also of serum soluble HLA-G, but these did not reach statistical significance. When leucocytes from healthy subjects were cultured for 7 days in