杀伤细胞免疫球蛋白样受体及其配体HLA-C基因多态性与不明原因早期复发性流产的相关性

目的:探讨杀伤细胞免疫球蛋白样受体及其配体HLA-C基因多态性与不明原因早期复发性流产易感性的关系。方法:留取不明原因早期复发性流产患者(38例,URSA组)及正常早孕妇女(35例,对照组)的蜕膜、绒毛组织,抽提基因组DNA,序列特异性引物聚合酶链反应检测蜕膜组织14种KIR基因的表达;DNA测序法分析绒毛滋养细胞HLA-C1、HLA-C2基因多态性。结果:14种KIR基因均以不同频率表达;KIR2DS1基因的频率在URSA组与对照组中分别为60.27%vs41.18%,两组相比,差异有显著性(P=0.03)。两组基因HLA-C1、HLA-C2在绒毛组织中呈不平衡表达,以HLA-C1基因占明显优势。URSA组与对照组HLA-C1基因频率分别为66.67%、81.03%,两组相比差异无显著性,P=0.657;URSA组HLA-C2的基因频率为33.33%,对照组HLA-C2的基因频率为19.07%,两组相比差异有显著性,P=0.007。结论:蜕膜NK细胞活化性KIR基因频率升高,与绒毛滋养细胞的HLA-C2基因结合,传递活化性信号活化NK细胞,可能是引起URSA发病的免疫遗传学因素之一。     

Description of two new HLA-C alleles in a black South African population

Two new HLA-C alleles, Cw*0333 and Cw*0217, were identified in a Black South African population. HLA-Cw*0333 differs from Cw*030201 by an A-->G substitution at nucleotide 323, yielding an unusual missense substitution of Cys for the conserved Tyr-84 at the antigen cleft terminus. Molecular modeling suggests that this alters the predicted interactions of this critical residue with the opposite alpha(2)-helix, the peptide COOH terminus and possibly KIR2DL2. The second allele, Cw*0217, differs from Cw*0205 by an A-->T substitution at nucleotide 368, resulting in a Tyr-->Phe substitution at residue 99 of the HLA-C beta-pleated sheet that likely influences peptide side-chain binding. Both Cw*0333 and Cw*0217 appear to have arisen by missense mutations, respectively, from the HLA-B*5801-Cw*0302 and B*080101-Cw*0205 haplotypes.     

HLA-Cw基因常规检测区外第1、5、6、7外显子核苷酸序列测定的研究及临床应用

目的 研究中国人群HLA-Cw基因第1、5、6、7外显子的分子遗传多态性,探讨增加第1、5 6 7外显子核苷酸序列测定在临床组织配型工作中的重要性及意义.方法 应用PCR-SBT法,对324份样本的HLA-Cw基因第2、3、4外显子作常规测序分型.对检出的模棱两可结果,设计HLACw第1、5 6 7外显子序列测序引物并优化测序反应条件,增加第1、5、6、7外显子核苷酸序列分析.结果 对HLA-Cw基冈第2、3、4外显子常规检测,一次性获得等位基因前4位数分型结果 的样本占23.8%(77/324);出现模棱两可结果的样本数占76.2%(247/324),检出的模棱两可等位基因组合有73种;增加HLA-Cw基因的第1、5、6、7外显子多态性检测,可解决Cw* 030201/030202、030301/0320N、Cw* 040101/0409N/0430、Cw* 070201/0750、Cw* 0403/0409N/0430和Cw* 080101/0822等10种常见的模棱两可等位基因组合.结论 在临床HLA-Cw基因配型中增加第1、5、6、7外显子多态性检测,有助于解决测序分型中的模棱两可的结果 和提高HLA-Cw基因分型精确度,对临床组织配型工作具有重要意义.     

Disease-association of different killer cell immunoglobulin-like receptors (KIR) and HLA-C gene combinations in reactive arthritis

Abstract

Background: Reactive arthritis (ReA) is sterile arthritis triggered by bacterial gastrointestinal or urogenital infections. Although the pathogenesis of ReA remains unclear, genetic factors seem to play an important role. Different killer cell immunoglobulin-like receptors (KIRs) and their corresponding specific histocompatibility leukocyte antigen-C (HLA-C) ligand genotypes have been implicated in susceptibility and resistance to infections and autoimmune diseases but have, thus far, not been investigated in ReA.

Methods: This study was conducted in 138 ReA patients (65 females, 73 males); aged 18–69 years (mean, 37 years) and 151 randomly selected healthy control individuals matched for ethnicity, age and sex. These subjects were genotyped for KIR genes and HLA-C alleles by polymerase chain reaction with sequence-specific primers.

Results: The frequencies of inhibitory KIR2DL2 and KIR2DL5 were significantly lower in the ReA patients than in the controls (p?=?.005 and p?=?.033, respectively). The presence of more than seven inhibitory KIR genes was protective (p?=?.016). Moreover, we found that activating KIR2DS1 alone or in combination with the HLA-C1C1 genotype (which indicates the absence of the HLA ligands for their homologous inhibitory receptor KIR2DL1) is associated with susceptibility to ReA (p?=?.039 and p?=?.011, respectively), whereas KIR2DL2 in combination with the HLA-C1 ligand is associated with protection against ReA (p?=?.039).

Conclusion: These observations indicate that high levels of activating and low levels of inhibitory KIR signals may affect the functions of NK cells and T cells. This imbalance enables the innate and adaptive immune responses of the host to be easily triggered by pathogens, resulting in the overproduction of local and systemic cytokines that contribute to the pathogenesis of ReA.     

Haplotypic association of two new HLA class I alleles: Cw*15052 and B*0706: evolutionary relationships of HLA-Cw*15 alleles

A novel HLA-Cw*15, B7 haplotype has been found in Caucasians. Molecular cloning studies demonstrate that this haplotype is constituted by the new alleles Cw*15052 and B*0706, which seem to be intermediate steps in the diversification of their respective allelic families. A pathway for the evolution of Cw*15 alleles is proposed.     

Nucleotide sequence of exons 2 and 3 of the novel HLA-Cw*12032 allele

A novel HLA-C nucleotide sequence was discovered in an individual of Pacific Island, Tongan ethnicity using sequencing based typing. The sequence was given an official allele designation HLA-Cw*12032 by the WHO Nomenclature Committee for Factors of the HLA System. The novel sequence has 2 bp substitutions compared to the HLA-Cw*1203 at codon 134 "T" to "C" and codon 135 "C" to "G". However, when converted to amino acid sequences HLA-Cw*1203 and HLA-Cw*12032 are identical and would not have direct clinical implications.     

A novel HLA-Cw*03 allele, Cw*033802, identified by sequence-based typing

New allele Cw*033802 showed one nucleotide difference with Cw*0338 at codon 99 (TAC-->TAT).     

Homozygous HLA-C1 is Associated with Reduced Risk of Relapse after HLA-Matched Transplantation in Patients with Myeloid Leukemia

Natural killer (NK) cells assume graft-versus-leukemia alloreactivity after hematopoietic stem cell transplantation (HSCT) through their inhibitory killer cell immunoglobulin-like receptors (KIRs). KIR2D family members recognize HLA-C alleles with Asn80 (HLA-C1) or Lys80 (HLA-C2). The predominance of HLA-C1 over HLA-C2 and the frequent presence of KIR2DL1 are characteristic of Japanese people. We compared clinical outcomes among homozygous HLA-C1 (HLA-C1/C1) patients and heterozygous HLA-C1/C2 patients who underwent HLA-matched HSCT for hematologic malignancies by assessing the data of 10,638 patients from the Japanese national registry. HLA-C1/C1 recipients had a lower rate of relapse than HLA-C1/C2 recipients after transplantation for acute myelogenous leukemia (AML) (hazard ratio [HR], .79; P?=?.006) and chronic myelogenous leukemia (CML) (HR, .48; P?=?.025), but not for acute lymphoblastic leukemia (HR, 1.36), lymphoma (HR, .97), or low-grade myelodysplastic syndrome (HR, 1.40). We then grouped AML and CML patients together and divided them into several subgroups. Advantages of HLA-C1/C1 recipients over HLA-C1/C2 recipients regarding relapse were observed irrespective of donor relation (related: HR, .79, P?=?.069; unrelated: HR, .77, P?=?.022), preparative regimen (myeloablative: HR, .79, P?=?.014; reduced intensity: HR, .73, P?=?.084), and occurrence of acute graft-versus-host disease (yes: HR, .70, P?=?.122; no, HR .71, P?=?.026) or cytomegalovirus reactivation (reactivated: HR .67,P?=?.054; nonreactivated: HR .71, P?=?.033); however, these advantages were not observed in recipients with a delay in achieving complete chimerism (HR, 1.06). The advantage of decreasing relapse and extending relapse-free survival of C1/1 over C1/2 KIR-ligand status was most pronounced in T cell-depleted HSCT (HR, .27; P?<?.001 and HR, .30; P?=?.002, respectively) and in children age <15 years (HR, .29; P?<?.001 and HR .31; P?<?.001, respectively). Our findings represent an important mechanism responsible for the immunity against HLA-C2–negative myeloid leukemia cells after HLA-matched transplantation.     

Correction of HLA-Cw*0501 and identification of HLA-Cw*0711

We describe a new HLA-C allele, Cw*0711, that differs from Cw*0704 by one residue in the intracytoplasmic region, and correct two errors in the published sequence of Cw*0501.