Abstract:

Objective    To explore the relation of expression of peripheral blood CD3+CD16+CD56+ natural killer T（NKT） cells with immune status and different concentrations of calcineurin inhibitor (CNI) in patients after renal transplantation. Methods    92 patients after renal  transplantation were divided into three groups according to rejection and  concentrations of CNI：patients without rejection in normal concentration(group A，58 cases), patients without rejection in lower concentration (group B，8 cases), and patients with rejection (group C，26 cases). 10 healthy individuals were selected as the controls. CD3+，CD3+CD4+，CD3+CD8+，CD3-CD16+CD56+NK and CD3+CD16+CD56+ NKT cells and human leucocyte antigen(HLA) antibodies were analyzed by flow cytometry.  Results    Percentages of CD3+CD16+CD56+ NKT cells in groups A,B,C and D were (4.29±2.57)%,(4.31±2.08)%,(1.23±1.06)% and (3.98±2.26)%，respectively. Percentages of NKT and NK cells，CD4+/CD8+，and the HLA antibodypositive rate in groups A and B had no significant difference compared with those in group D. The percentage of CD3+CD16+CD56+NKT  cells was lower in group C compared with that in group D (P<0.05). Percentages of NK cells and CD4+/CD8+, and the HLA antibodypositive rate in group C were significantly higher than in group D(P<0.05).   Conclusion     CD3+CD16+CD56+ NKT cells are lowly expressed when rejection occurs，and HLA antibodies occur in these patients. Expression of NKT cells is normal and stable in patients without rejection, and is not affected by CNI concentrations. NKT cells play an important role in immunosuppression in patients after renal transplantation.

Key words: Natural killer T cells; Renal transplantation; Rejection