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.
Adult ; Alleles ; Asian Continental Ancestry Group/*genetics ; Female ; Genotype ; Graft Rejection ; Graft Survival ; HLA-C Antigens/*genetics ; Homozygote ; Humans ; Killer Cells, Natural/cytology/immunology ; Ligands ; *Liver Transplantation ; Male ; Middle Aged ; Proportional Hazards Models ; Receptors, KIR/chemistry/*genetics/metabolism ; Republic of Korea ; Tissue Donors ; Transplantation, Homologous

Killer cell immunoglobulin-like receptors (KIRs) which are mainly expressed on natural killer (NK) cells are implicated in many virus infections. However, it is unclear whether or not KIRs are associated with susceptibility to Epstein-Barr virus (EBV) infection related diseases. Therefore, the purpose of our study was to investigate possible correlation between polymorphisms of KIR genes and infectious mononucleosis (IM)/EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH). The polymorphisms of KIR genes were detected by polymerase chain reaction with sequence-specific primers (PCR-SSP). The results would contribute to clarify the association of KIRs with EBV induced diseases, and provide new insights into the role of NK cells and innate immune response against viral infections and/or subsequent progression.
Case-Control Studies ; Child ; Child, Preschool ; China ; Disease Progression ; Female ; Herpesvirus 4, Human ; physiology ; Humans ; Immunity, Innate ; Infectious Mononucleosis ; genetics ; immunology ; virology ; Killer Cells, Natural ; immunology ; metabolism ; Lymphohistiocytosis, Hemophagocytic ; genetics ; immunology ; virology ; Male ; Polymerase Chain Reaction ; Polymorphism, Genetic ; Receptors, KIR ; genetics ; metabolism

Natural killer (NK) cells play an important role in innate immunity, especially in the response to viral infections, such as hepatitis C virus (HCV). Killer cell immunoglobulin-like receptors (KIRs) are the primary receptors of NK cells that mediate innate immunity. KIRs are also involved in acquired immunity, because some KIRs are expressed on the surface of certain subsets of T cells. In this study, the frequency of KIR genes, HLA-C allotypes, and combinations of KIR genes with their HLA-C ligands were evaluated in two different groups of the Korean population: controls and patients with chronic HCV infection. The study population consisted of 147 Korean patients with chronic HCV infection. The frequency of KIR2DS2 in patients with chronic HCV infection was 9.5% which was significantly lower than 19.5% of the control (P < 0.01). However, there were no significant differences in the frequency of other KIR genes, HLA-C allotypes or different combinations of KIR genes with their HLA-C ligands. This study can contribute to the further prospective study with a larger scale, suggesting the assumption that KIR2DS2 might aid in HCV clearance by enhancing both the innate and acquired immune responses of people in Korea.
Adult ; Aged ; Female ; Genes, MHC Class I ; Genotype ; HLA-C Antigens/genetics ; Hepacivirus/immunology ; Hepatitis C, Chronic/*genetics/immunology ; Humans ; Killer Cells, Natural/immunology/virology ; Male ; Middle Aged ; Receptors, KIR/*genetics/immunology ; Republic of Korea ; T-Lymphocyte Subsets/immunology

The aim of this study was to investigate how the killer immune globulin-like inhibition receptor (KIR) in match with HLA-Cw impacts on NK cell activity. Mononuclear cells were isolated in 20 ml peripheral blood from 27 healthy persons by Ficoll-Hypaque and purified by NK cell isolation kit. Target cells were mononuclear cells isolated from bone marrow of 30 de novo AML patients. The KIR expression were detected by flow cytometry with antibodies against CD158a, CD158b. The 2 ml of peripheral blood from healthy persons and AML patients were collected, the DNA was extracted by using PROTRANS method, the HLA-Cw and KIR gene were detected by PCR-SSP typing with sequence specific primers. The NK cell cytotoxicity against AML cells was determined by MTT after combination of KIR with HLA-Cw gene. The results indicated that the purity of NK cells was (90.8 +/- 6.08)%. The less the KIR/HLA-Cw matched, the more activity was shown in NK cells. When no match of NK cell/target cell (KIR/HLA-Cw) there was, the cytotoxicity was (50.66 +/- 8.40)%, 1 or 2 matches showed cytotoxicity of (38.28 +/- 6.71)% and (19.74 +/- 4.15)% (p < 0.001). Expression level of KIRs on NK cells also was related with cytotoxicity level (p < 0.001). It is concluded that the interaction between inhibitory KIR and HLA ligands, and also expression level of KIRs on NK cells both impact significantly on NK cell function, that the less match of KIR/HLA-Cw, and the less expression of KIRs on NK cells result in the stronger NK cell cytotoxicity.
Adult ; Female ; Genotype ; HLA-C Antigens ; genetics ; Humans ; Killer Cells, Natural ; immunology ; metabolism ; Male ; Receptors, KIR ; genetics

OBJECTIVETo investigate the genotypes of natural killer cell immunoglobulin-like receptor (KIR) genes and their frequencies in Chinese subjects and explore the mechanism of the actions of nature killer cells.

METHODSThe DNA samples were obtained from 67 randomly selected unrelated Chinese Han individuals for genotyping of the KIR genes using PCR with sequence-specific primers (PCR-SSP), and the frequencies of the KIR genes in these Chinese subjects were compared with the reported frequencies in populations of other nationalities.

RESULTSSixteen KIR genes were identified in these Chinese subjects, and 87.5% of these genes were expressed at frequencies above 0.35. Fourteen functional KIR genes combined into 25 KIR genotypes, among which the most frequent genotype KIR-2DL1-2DL3-2DL4-3DL1-3DL2-3DL3-2DS4 showed a frequency of 0.373, while the frequencies of all the other genotypes were no greater than 0.09. Comparison of the KIR combinations in Chinese Han population with those of Japanese, Korean, and Caucasians populations identified 8.93% of the KIR combinations shared by all these populations; the Chinese, Koreans and Caucasians shared 5.36% common KIR combinations, whereas only 1.79% common combinations were found in Chinese and Caucasians. In this study, 16 new gene combinations were identified (25.28%).

CONCLUSIONThis study shows the high-frequency distribution of a single KIR gene polymorphism. The KIR combination KIR-2DL1-2DL3-2DL4-3DL1-3DL2-3DL3-2DS4 has the highest frequency in Chinese, Japanese, Korean and Caucasian populations, indicating that inhibitory signal transduction pathway plays an important role in the function of the natural killer cells. This study provide clues for new approaches for improving the prognosis of kidney transplantation by enhancing or inhibiting the function of the natural killer cells instead of life-time usage of immunosuppressive agents.

Asian Continental Ancestry Group ; ethnology ; genetics ; Gene Frequency ; Genotype ; Humans ; Killer Cells, Natural ; immunology ; Polymorphism, Genetic ; Receptors, KIR ; genetics ; Sequence Analysis, DNA

This study was purposed to investigate the killer immunoglobulin-like receptor (KIR) genotype in patients with hematological malignancies. The sequence specific primer-polymerase chain reaction (PCR-SSP) technique was performed for the amplification of six inhibitory KIR genes (KIR2DL1-2DL4, 3DL1-3DL2) and six activating KIR genes (KIR2DS1-S5, 3DS1). The methods of KIR-SSP was used to determine the KIR genotypes of 54 leukemia patients, including 14 patients with acute myeloid leukemia (AML), 16 with acute lymphoblastic leukemia (ALL), 20 with chronic myeloid leukemia (CML), 3 with myelodysplastic syndrome (MDS) and 1 with acute myeloid-lymphoblast leukemia (AMLL). 54 patients were classified as high risk group (n = 27) and standard risk group (n = 27). The expression of KIR in NK cells and T cells was detected by flow cytometry. The frequencies of activating KIR genes in standard risk group were higher than those in high risk group, especially 2DS1 (p = 0.014), or 2DS2 (p = 0.046), or 3DS1 (p = 0.027). However, the frequencies of inhibitory KIR genes in standard risk group were similar to those in high risk group (p > 0.05). The frequencies of activating KIR genes were also higher in standard risk patients with acute AML, as compared with those in high risk patients with acute AML, particularly 2DS1 (66.7% vs 29.4%, p = 0.022), 2DS2 (57.6% vs 17.6%, p = 0.013), and 2DS3 (33.3% vs 5.9%, p = 0.039). The percentages of patients in high-risk group who expressed more than two kinds of activating KIRs were lower that those in standard-risk group (p = 0.035). There was no difference in the expressions of CD158a, CD158b, and CD158e on NK cells and T cells between high-risk group and standard-risk group (p > 0.05). In conclusions, different expressions of activating KIR genes were found in patients between high-risk group and standard-risk group.
Genotype ; Hematologic Neoplasms ; genetics ; immunology ; Humans ; Killer Cells, Natural ; immunology ; metabolism ; Receptors, KIR ; genetics ; Risk Factors ; T-Lymphocytes ; immunology ; metabolism

OBJECTIVETo study the effects of small interfering RNA (siRNA)-mediated silencing of CD158b expression on the efficiency of the natural killer (NK) cells in killing allogeneic dendritic cells.

METHODSAfter the knockdown of CD158b by CD158b -SiRNA, the CD158b mRNA expression in natural killer cells was examined by qRT-PCR and the CD158b protein expression by flow cytometer. The cytotoxic activity of RNAi-NK cells and normal NK cells against the allogeneic dendritic cells was detected by LDH release assay.

RESULTSThe CD158b mRNA expression and its protein expression were decreased significantly in the NK cells by CD158b siRNA (P/0.05). The cytotoxic activities of alloreactive NK cells generated by RNAi CD158b expression against allogeneic dendritic cells were increased significantly.

CONCLUSIONSilencing CD158b gene can inhibit the NK cell CD158B mRNA and protein expression. Alloreactive NK cells generated by RNAi CD158b expression have the potential for use in interventions of GVHD.

Bone Marrow Transplantation ; immunology ; methods ; Cytotoxicity, Immunologic ; immunology ; Dendritic Cells ; cytology ; immunology ; Flow Cytometry ; Gene Silencing ; Graft vs Host Disease ; immunology ; Humans ; Killer Cells, Natural ; cytology ; immunology ; RNA Interference ; RNA, Messenger ; biosynthesis ; genetics ; RNA, Small Interfering ; genetics ; Receptors, KIR ; metabolism ; Receptors, KIR2DL3 ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction

The purpose of study was to investigate the impact of killer immunoglobulin-like receptor (KIR) and its ligand on haploidentical bone marrow transplantation. 74 cases were analyzed for the distribution frequencies and characteristics of KIR and its ligand as well as the impact of KIR ligand for the haploidentical bone marrow transplantation in terms of the overall survival, disease-free survival (DFS), GVHD and relapse. The results showed that among the 19 KIR genotypes currently nominated KIR2DL1, KIR2DL4 and KIR3DL2-3 could be detected in all the cases. Other high frequency genotypes included KIR3DP1 (98.6%), KIR2DP1 (98.6%), KIR3DL1 (97.3%) and KIR2DL3 (97.3%). Inhibitory receptor genotypes were 1.37-fold of activating receptor genotypes. KIR2DL1, KIR3DL2, KIR3DL3 and KIR2DL4 were found in all haplotypes and at least one genotype of KIR2DL2 and/or KIR2DL3 existed in all haplotypes. Among the 14 genotypes found in the test, the HLA-Cw7 was the most popular (37.8%) and the group 2 (HLA-Cw1, 3, 7, 8, 13, 14) recognized by KIR2DL2/2DL3 counted for 43.2%. The incompatibility of KIR for 32 cases of haploidentical BMT was 43.8%, of which 9/14 were KIR2DL incompatible, 5/14 were KIR2DL2 or KIR3DL1 incompatible. Among the 46 cases of haploidentical BMT, 29 cases were HLA-Cw matched and 14 cases were mismatched. The completed mismatch ratio of HLA-Cw was 30.4% and the match ratio was 63.4%. The survival rate was higher for the 14 cases of KIR genotype compatible group than the 13 cases of KIR genotype incompatible group (p = 0.032). The disease-free survival was significantly higher for the 17 cases of mismatched KIR ligands (HLA-Cw) group than the matched group (p = 0.024). The survival rate was higher in GVHD group than that in non-GVHD group when the KIR ligand was missing. The acute and severe GVHD was related to the existence of activating receptor of KIR2DS1/2DS2. The incompatibility group was accompanied with frequent acute and severe GVHD and less relapse and vice versa for the compatibility group. One patient died after BMT among the 14 mismatched KIR ligand group suffering from myelogenous leukemia while 4 patients out of 12 patients died in the matched group. It is concluded that the haploidentical BMT is characterized by mismatch between donor and recipient and its immunological reactions also features by the incompatibility of KIR genotype and missing ligand. The missing ligand for the donor KIR has strong effect on the outcome of BMT and it means a lot to analyze the KIR genotype and its ligand for the selection of best donor and prognostic evaluation in haploidentical BMT.
Adolescent ; Adult ; Bone Marrow Transplantation ; immunology ; Child ; Child, Preschool ; Female ; Genotype ; Graft vs Host Disease ; immunology ; HLA-C Antigens ; genetics ; immunology ; Haplotypes ; genetics ; immunology ; Hematologic Neoplasms ; therapy ; Histocompatibility ; genetics ; immunology ; Humans ; Ligands ; Male ; Middle Aged ; Receptors, KIR ; genetics ; immunology ; Young Adult

OBJECTIVETo study the biological function of killer cell immunoglobulin-like receptor (KIR) and the role of donor inhibitory KIR and recipient genetic background in HLA matched unrelated hematopoietic stem cell transplantation (HSCT).

METHODSHLA genotype of 51 patients (ALL 18 cases, CML 15 cases, AML 10 cases and others 8 cases) and their respective matched unrelated donors from Database of China Marrow Registration was determined by polymerase chain reaction sequence oligonucleotide probes (PCR-SSOP) and sequence specific primers (PCR-SSP). The KIR genotype was determined by PCR-SSP.

RESULTSAll the patients and the donors expressed KIR2DL1, KIR2DL2/L3, KIR2DL4, KIR3DL2 and KIR3DL3. 96.7% individuals expressed KIR3DL1. Among them, 21.57% of KIR was completely identical, while 78.43% was not. Of the non-identical KIRs, 25.49% were the recipient's KIR genotype containing the donor's ones, and 27.45% was the donor's containing the recipient's. 74.62% of donor's KIR2DL1 lacked recipient's C2 ligand, 5.91% of donor's KIR2DL2/L3 lacked recipient's C1 ligand, 19.74% of donor's KIR3DL1 lacked recipient's Bw4 ligand and 54.91% of donor's KIR3DL2 lacked recipient's A3, A11 ligand.

CONCLUSIONKIR genotype and HLA class I antigen are inherited independently. KIR2DLI and KIR3DL2 of donors may cause alloreactivity of NK cell. The mismatch of KIR/HLA in donor-recipient plays a very important role in matched unrelated allo-HSCT. The outcome of HSCT can be better predicted by the model of the presence of KIRs on the donor' sNK cells and the absence of corresponding KIR ligand in the recipient's HLA.

Adolescent ; Adult ; Child ; Child, Preschool ; Female ; Gene Frequency ; Genotype ; HLA Antigens ; genetics ; Hematopoietic Stem Cell Transplantation ; Humans ; Infant ; Killer Cells, Natural ; immunology ; Male ; Receptors, KIR ; genetics ; Transplantation, Homologous

The aim of study was to analyze natural killer immunoglobulin (Ig)-like receptor (KIR) gene content in HLA-identical sibling and to investigate the possibility of their KIR match. Samples were genotyped for HLA by Luminex method and polymerase chain reaction sequence based typing, the KIR gene was detected by polymerase chain reaction sequence-specific primers. The results showed that 17 KIR genes could be observed in the 27 pairs HLA-A, -B, -Cw and -DRB1 locus identical sibling samples. All individuals contained KIR3DL3, KIR3DP1, KIR2DL4 and KIR3DL2.; 20 different KIR genotypes and 12 haplotypes have been found, the most common KIR genotypes was 2,2 with frequency 29.6% and KIR haplotype was 2 with frequency 53.0%. The A KIR haplotype was the most prevalent with frequency 67.2%; 12 pairs (44.4%) HLA identical sibling donor-recipients showed KIR match in genotype and haplotype, 13 pairs (48.1%) with one KIR haplotype mismatch and 2 pairs (7.4%) with two KIR haplotype mismatch; 1 pair was matched between donor KIR2DL1 and patient HLA-Cw (Lys80) ligand, 17 pairs were matched between KIR2DL2/KIR2DL3 and HLA-Cw (Asn80) ligand, 5 pairs were matched between KIR3DL1 and HLA-Bw4 ligand. It is suggested that the probability of KIR mismatch is high in HLA-identical sibling.
HLA Antigens ; genetics ; immunology ; Haplotypes ; Hematopoietic Stem Cell Transplantation ; methods ; Histocompatibility Testing ; Humans ; Multigene Family ; Receptors, KIR ; genetics ; Siblings