Research On Expression Of NK Cell Receptors/Ligands In Acute Leukemia Patients And Its Relationship With GVHD And Relapse After Haploidentical Hematopoietic Stem Cell Transplantation

This study aimed to explore the immune significance of differentexpression of the activating receptor NKG2D and the inhibitory receptorNKG2A on CD56+CD16+CD3-natural killer (NK) cells and CD3~+T cells,and the expression of major histocompatibility complex classâ… -relatedchain A/B (MICA/B) and human leukocyte antigen-E (HLA-E) onleukemia cells between acute lymphocytic leukemia (ALL) and acutemyeloid leukemia (AML). And the impact on graft versus host disease(GVHD) and relapse of killer cell immunoglobulin-like receptors-ligand(KIR-L) incompatibility after haploidentical hematopoietic stem celltransplantation (haplo-HSCT) were studied as well.Flow cytometry was used to detect the expression of NKG2D andNKG2A on NK cells and CD3~+T cells in sixty acute leukemia patients,bone marrow. Furthermore, the expression of MICA/B and HLA-E onacute leukemia cells were also detected by flow cytometry. ALL and AMLpatients involved are respectively thirty. We retrospectively analyzed theimpact on graft versus host disease (GVHD) and relapse of KIR-Lmismatch of 45 patients who received haplo-HSCT in hematologydepartment transplantation center in General Hospital of Air Force.The expression of both NKG2D and NKG2A on NK and CD3~+T cellsin ALL patients has no significant difference compared with in AMLpatients(P>0.05). The positive rate of MICA/B and HLA-E -expressingacute leukemia cells is both significantly higher in ALL patients than in AML patients(P<0.05). Sixteen patients suffered acute graft versus hostdisease (aGVHD) with the incidence of 35.6%, three of whom sufferedgradeâ…¡-â…£of aGVHD and the rate is 6.7% after haplo-HSCT. Tenpatients relapsed and the rate is 22.2%. The incidence of aGVHD andchronic graft versus host disease(cGVHD)as well as relapse rate in bothdonor/receptor HLA-Cw match group and KIR match group is lower thanthe mismatch group. But in donor/receptor graft versus host (GVH)groupaGVHD is lower and cGVHD along with relaspe higher than no GVHgroup. Analysis of the survival rate of 3 years: HLA-Cw match is lowerthan mismatch group and the KIR match group is higher. The overallsurvival in GVH group is lower than mismatch group.The different function of immune cells in ALL and AML patientsmaybe depend on the expression of ligands on leukemia cells and has nocorrelation with the expression of activating or inhibiting receptors on NKcells and T cells. HLA-Cw match and KIR match are related to lowerGVHD and relapse. But HLA-Cw mismatch and KIR match could improvethe survival rate. KIR-L incompatibility is probably relevant to loweraGVHD but higher cGVHD and relapse after haplo-HSCT, but does notaffect the 3 years survival rate.