The Impact Of KIR/HLA Receptor-ligand Model And KIR Ligands Expression On The Prognosis Of Single Unrelated Cord Blood Transplantation

PART ? The Impact of KIR/HLA Receptor-Ligand Model on the Prognosis of Single Unrelated Cord Blood TransplantationPurpose: To research the impact of the killer cell immunoglobulin like receptor/human leukocyte antigen(KIR/HLA)receptor ligand model in UCBT.Method: Between July 2012 and June 2018,270 patients with malignant hematologic disease receiving single-unit UCBT and all patients-donor couples receive HLA and KIR genotypes.Result: A total of 270 patients(146 males,124 females)were included in this retrospective study.Median age is 13 years,range 1–62 years.All patients received a myeloablative conditioning regimen(without ATG).The median follow-up time since the transplant for the surviving patients was 742 days(335-2512 days).All patients were divided into two groups based on the absence or the presence of one of the C-ligands for inhibitory KIR.Group 1(n=174)patients lacked a C-ligand for inhibitory KIR present on UCB NK cells,(patients homozygous C1/C1 or C2/C2).Group 2(n=96)patients presence of both C ligands for inhibitory KIR in the receptor(patients heterozygous C1/C2).The ratio of neutrophil engraftment for group 1 and 2 were both 98.9%,the median time to neutrophil engraftment for group 1 and 2 was 16 days vs 17 days(P=0.705).The ratio of platelet engraftment was 88.5% for group 1 and 87.5% for group 2,the median time to platelet engraftment was 35 days vs 38.5 days(P= 0.317).The cumulative incidence of ?-? acute GVHD in 100 days was 38.7% for group 1 and 50.0% for group 2(P=0.0751),but multi-variate analysis showed that HLA-C ligand absence was an independent protective factor for II-IV acute GVHD after transplantation [HR=1.518(95%CI 1.029~ 2.242),P=0.036].Patients with absence of a C-ligand for inhibitory KIRs(Group 1)showed a lower relapse rate than patients with both C-ligands(group 2):17.7% vs 22.7% at 3 years(P=0.288).There was no statistically significant difference between the two groups in 3-year disease-free survival(64.9% vs 55.4%,P=0.0819),non-relapse mortality(12.1% vs 16.7%,P=0.328),3-years OS(69.3% vs 60.5%,P=0.0792).ALL patients were divided into Bw4+ group and Bw4-group according to whether they express Bw4 or not.There were no statistical differences between the two groups in all prognostic indicators(ANC and platelet engraftment,incidence of a GVHD,relapse rate,3-years OS,NRM,and DFS).Conclusion:1)In unrelated cord blood transplantation,patients lacking a KIR-ligand of HLA group C1 or C2 had a lower incidence of grades ?-? acute GVHD after s UCBT.When patients lacked KIR ligand we need to be alert to the dangers of acute GVHD and take early interventions if necessary.2)Patients with acute lymphoblastic leukemia had a high risk of recurrence rate after unrelated cord blood transplantation.PART ? The Impact of KIR Ligands Expression on the Prognosis of Single Unrelated Cord Blood TransplantationPurpose: To research the impact of the KIR ligands expression on the prognosis of s UCBT.Method: Between February 2011 and June 2018,436 patients with malignant hematologic disease receiving single-unit UCBT were divided into two groups based on whether the KIR ligands compatible or not(group1: KIR ligands compatible,group2: KIR ligands incompatible).The median follow-up time since the transplant for the surviving patients was 742 days(335-2512 days).Result: A total of 436 patients(263 males,173 females)were included in this retrospective study.Median age is 12 years,range 1–62 years.All patients received a myeloablative conditioning regimen(without ATG).There were no statistical differences between the two groups in all prognostic indicators(ANC and platelet engraftment,incidence of a GVHD,relapse rate,3-years OS,NRM,and DFS).Conclusion:Our results suggest that KIR ligands incompatible has no significant survival benefits to UCBT patients.