Human Leukocyte Antigen-C Genotype and Killer Immunoglobulin-like Receptor-Ligand Matching in Korean Living Donor Liver Transplantation.
BACKGROUND
The interaction between killer immunoglobulin-like receptors (KIRs) and HLA class I regulates natural killer (NK) cell cytotoxicity and function. The impact of NK cell alloreactivity through KIR in liver transplantation remains unelucidated. Since the frequency of HLA-C and KIR genotypes show ethnic differences, we assessed the impact of HLA-C, KIR genotype, or KIR-ligand mismatch on the allograft outcome of Korean liver allografts.


METHODS
One hundred eighty-two living donor liver transplant patients were studied. Thirty-five patients (19.2%) had biopsy-confirmed acute rejection (AR), and eighteen (9.9%) had graft failure. The HLA-C compatibility, KIR genotypes, ligand-ligand, and KIR-ligand matching was retrospectively investigated for association with allograft outcomes.


RESULTS
Homozygous C1 ligands were predominant in both patients and donors, and frequency of the HLA-C2 allele in Koreans was lower than that in other ethnic groups. Despite the significantly lower frequency of the HLA-C2 genotype in Koreans, donors with at least one HLA-C2 allele showed higher rates of AR than donors with no HLA-C2 alleles (29.2% vs 15.7%, P=0.0423). Although KIR genotypes also showed ethnic differences, KIR genotypes and the number of activating KIR/inhibitory KIR were not associated with the allograft outcome. KIR-ligand mismatch was expected in 31.6% of Korean liver transplants and had no impact on AR or graft survival.


CONCLUSIONS
This study could not confirm the clinical impact of KIR genotypes and KIR-ligand mismatch. However, we demonstrated that the presence of HLA-C2 allele in the donor influenced AR of Korean liver allografts.
Department of Laboratory Medicine, Seoul St. Mary's Hospital, College of Medicine, the Catholic University of Korea, Seoul, Korea.
Hyeyoung
H
Lee
Department of Biomedical Science, Graduate School, the Catholic University of Korea, Seoul, Korea.
Ki Hyun
KH
Park
Department of Biomedical Science, Graduate School, the Catholic University of Korea, Seoul, Korea.
Hye Sun
HS
Park
Department of Biomedical Science, Graduate School, the Catholic University of Korea, Seoul, Korea.
Ji Hyeong
JH
Ryu
Department of Laboratory Medicine, Seoul St. Mary's Hospital, College of Medicine, the Catholic University of Korea, Seoul, Korea.
Jihyang
J
Lim
Department of Laboratory Medicine, Seoul St. Mary's Hospital, College of Medicine, the Catholic University of Korea, Seoul, Korea.
Yonggoo
Y
Kim
Department of Surgery, Seoul St. Mary's Hospital, College of Medicine, the Catholic University of Korea, Seoul, Korea.
Gun Hyung
GH
Na
Department of Surgery, Seoul St. Mary's Hospital, College of Medicine, the Catholic University of Korea, Seoul, Korea.
Dong Goo
DG
Kim
Department of Laboratory Medicine, Seoul St. Mary's Hospital, College of Medicine, the Catholic University of Korea, Seoul, Korea. ejoh@catholic.ac.kr.
Eun Jee
EJ
Oh
D000328:Adult; D000483:Alleles; D044466:Asian People / Q000235:genetics*; D005260:Female; D005838:Genotype; D006084:Graft Rejection; D006085:Graft Survival; D015236:HLA-C Antigens / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology; D008024:Ligands; D016031:Liver Transplantation; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D054340:Receptors, KIR / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D056910:Republic of Korea; D014019:Tissue Donors; D014184:Transplantation, Homologous
D015236:HLA-C Antigens; D008024:Ligands; D054340:Receptors, KIR
Allograft outcome; HLA-C; KIR-ligand mismatch; Killer immunoglobulin-like receptors; Liver transplantation