[Variable expression of CD28 costimulatory molecule and CTLA4 inhibitory molecule on peripheral blood CD4+ cells in kidney allograft recipients with and without acute graft rejection].

Unlabelled: Alloimune activation is one of the most significant post transplant events, which results in increased expression of costimulatory molecules. These molecules have been suggested to play a role in determining the outcome of immune response including graft rejection.

Material And Methods: We examined the CD28 and both surface and intracellular CTLA-4 expression on freshly drawn and anti-CD3+rlL-2 stimulated peripheral blood CD4+ T cells in kidney transplant recipients with acute graft rejection and with non-complicated post transplant course. Dual immunofluorescence and flow cytometry methods were used. The proportion of freshly isolated CD4+/ CTLA4 was higher in both groups of graft recipients in comparison to healthy controls reflecting in vivo allostimulation.

Results: We found the increased percentage of CD4+ cells expressing surface CTLA4 after stimulation, unstimulated intracellular CTLA4 and lower percentage of CD4+ cells expressing CD28 after stimulation in kidney recipients without rejection.

Conclusions: Our results indicate the possible relationship between the expression pattern of CTLA4 inhibitory molecule on CD4+ cells and clinical course after renal transplantation.