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31.
Abstract: Previous studies have indicated that certain alleles of HLA-DR and -DQ genes were strongly associated with susceptibility and resistance to insulin-dependent diabetes mellitus (IDDM), and the role of DQ molecule in IDDM has been suggested. To further clarify the association of DQ alleles with IDDM, we determined the nucleotide sequences of full-length cDNA from 13 DQA1 alleles and 14 DQB1 alleles. The sequencing analysis revealed sequence polymorphisms outside the hypervariable region of DQ genes. We then analyzed the DQA1 and DQB1 polymorphisms along with that of DRB genes in 86 B-lymphoblastoid cell lines (B-LCLs) from various ethnic groups and in healthy unrelated Japanese and Norwegian individuals. The allelic and haplotypic distributions in each population revealed the characteristic haplotypic formation in the HLA class II region. HLA genes in 139 Japanese and 100 Norwegian IDDM patients were analyzed. DQB1*0301 was negatively associated with IDDM in both ethnic groups, irrespective of associated DRB1 and DQA1 alleles. In DQB1*0302 positive populations, which represented a positive association with IDDM in both ethnic groups, DRB1*0401, *0404, *0802 haplotypes increased in the patients, whereas DRB1*0406 haplotype decreased. Considering about the hierarchy in DRB1 alleles with IDDM susceptibility (DRB1*0401>*0404>*0403 in Norwegian and DRB1*0802>*0403>*0406 in Japanese), the genetic predisposition to IDDM is suggested to be defined by the combination of DR-associated susceptibility and DQ-associated susceptibility and by the DQ-associated resistance which is a dominant genetic trait.  相似文献   
32.
Activation of certain adhesion molecules within vascular endothelium and the surrounding extravascular space is a critical event in the recruitment and targeting of an inflammatory response or autoimmune attack to a particular tissue site. We have recently demonstrated that the adhesion of lymphocytes to cultured retroocular fibroblasts obtained from patients with Graves' ophthalmopathy (GO) is mediated predominantly by the interaction of lymphocyte function-associated antigen-1 (LFA-1), expressed on lymphocytes, with intercellular adhesion molecule-1 (ICAM-1), expressed by these cells following exposure to interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha), IL-1 alpha or purified thyroid-stimulating immunoglobulins. We now report the expression and localization in situ of several adhesion molecules, ICAM-1, endothelial leucocyte adhesion molecule-1 (ELAM-1), vascular cell adhesion molecule-1 (VCAM-1), and LFA-3 in retroocular tissues derived from patients with severe GO (n = 4) and normal individuals (n = 3). Serial cryostat sections of tissue specimens were processed for immunoperoxidase staining using various MoAbs against ICAM-1, ELAM-1, VCAM-1 and LFA-3. In addition, consecutive sections were stained with MoAbs against LFA-1, CD45RO (UCHL-1)DR-human leucocyte antigen (HLA-DR), CD11b/CD18 (Mac-1), and CD11c/CD18 (p150,95). In GO-retroocular tissues, strong immunoreactivity for ICAM-1 and LFA-3 was detected in blood vessels (> 90%), in perimysial fibroblasts surrounding extraocular muscle fibres, and in connective tissue distinct from extraocular muscle. No ICAM-1 or LFA-3 immunoreactivity was present in extraocular muscle cells themselves. ICAM-1 and LFA-3 immunoreactivity in normal tissues was minimal or absent both in connective and muscle tissues. Vascular endothelium was strongly positive for ELAM-1 and VCAM-1 in GO-retroocular tissues, while VCAM-1 immunoreactivity was minimal (< 5% of blood vessels) and ELAM-1 immunoreactivity was generally absent in normal retroocular tissue. LFA-1-expressing, activated mononuclear cells and memory T lymphocytes (CD3+/CD45RO+) were only detected in GO-retrocular tissues, and were mainly localized around blood vessels and in areas of ICAM-1-expressing connective and perimysial tissue. HLA-DR expression was restricted to GO-tissue specimens, with strong immunoreactivity detected in blood vessels, macrophages and connective tissue and perimysial fibroblasts. No HLA-DR was detectable in extraocular muscle cells. In conclusion, infiltration of the orbit in GO by mononuclear cells, and their targeting within the orbit, may depend upon the coordinate expression of certain adhesion and MHC molecules.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
33.
We investigated the association between human leucocyte antigen (HLA) antigens and lymph node metastasis in 724 gastric cancer patients. Among patients who had poorly differentiated adenocarcinoma with or without HLA-DR4 antigen, lymph node metastasis was detected in 80.8 and 54.9%, respectively (relative risk (RR)=3.5, P = 0.0005, corrected P = 0.0285). It was more common in patients with a family history of cancer death (RR = 7.7). Among signet ring cell carcinoma patients with or without HLA-1152 antigen, lymph node metastasis was detected in 57.7 and 19.7%, respectively (RR =5.6, P=0.0001, corrected P=0.0086). It was more common in patients who were smokers (RR = 8.3). Our findings suggest that HLA-DR4 and HLA-1152 antigens are associated with lymph node metastasis in gastric cancer.  相似文献   
34.
The DR7-associated Dw specificities, Dw11, Dw17 and DB1 were investigated with regard to DRB- and DQB-gene polymorphism, as revealed by RFLP analysis using the restriction enzyme TaqI. In the 22 DR7 homozygous cell lines investigated, each of these Dw specificities was found to correlate to one specific RFLP defined DR-DQ haplotype. In addition, a clear linkage disequilibrium to a specific HLA-B locus allele for each Dw specificity was noted, indicating that the Dw subtypes of DR7 often are associated with a conserved HLA-B-DR-DQ haplotype. Only one genetically homozygous cell line, PLH, deviated from these correlations. This cell line, notably derived from an individual with a deletion of the 21-hydroxylase B-gene (21-OHB), caries the HLA haplotype Bw47, DR7, DQw2, DB1, but displayed a DRB RFLP otherwise found in association with Dw17.  相似文献   
35.
Ten novel HLA-DRB1 and one DRB3 alleles are described. Eight of the variants are single-nucleotide substitutions, four resulting in an amino acid change (DRB1*1145, *1148, *0828 and *1514) and four with silent substitutions (DRB1*040504, *130103, *160502 and DRB3*020204). Two alleles differ by two nucleotide changes altering one (DRB1*1447 and *1361) amino acid and one allele alters three nucleotides and two amino acids.  相似文献   
36.
目的 :探讨碘在自身免疫性甲状腺疾病 (AITD)发病中的作用及机制。方法 :选择具有遗传倾向疾病Graves病一级亲属的外周血单个核细胞 (PBMNC) ,采用细胞培养和免疫印迹技术 ,检测 Na I对 PBMNC HL A - DR表达的影响。结果 :Graves病一级亲属 :PBMNC HL A- DR表达量随培养液 Na I浓度增加而递增 ;而对正常无遗传倾向者 PBMNC HL A- DR表达量无影响。结论 :过多的碘可以上调有遗传倾向者 PBMNC HL A- DR表达。  相似文献   
37.
目的探讨系统性红斑狼疮患者外周血中B淋巴细胞及其活化状况与疾病活动性的关系。方法应用流式细胞术检测活动期与稳定期系统性红斑狼疮患者外周血中CD19+、CD23+/CD19+及HLA-DR+/CD19+细胞的表达情况;同时应用免疫学方法检测血清中ds-DNA与ANA水平。结果活动期患者CD19+、CD23+/CD19+及HLA-DR+/CD19+细胞表达率均高于稳定期患者及正常对照组,差异均有显著性意义;稳定期患者CD23+/CD19+表达很低,而HLA-DR+/CD19+双阳性细胞表达率高于正常对照组,但差异无显著性意义;且CD23+/CD19+双阳性细胞表达率与病情积分、ds-DNA及ANA均成正相关(P<0.01),而HLA-DR+/CD19+双阳性细胞与三者无相关关系(P>0.05)。结论活动期与稳定期患者均存在B淋巴细胞的克隆性增生与异常活化,B细胞的异常活化是病情活动的直接原因,晚期B细胞的异常活化是系统性红斑狼疮患者难彻底治愈与病情反复的原因之一。  相似文献   
38.
 【目的】探讨再生障碍性贫血(再障)儿童TCR Vβ24个亚家族T细胞克隆性及其与HLA—DRB1*15的关系。【方法】再障儿童17例(SAA14例,MAA3例),采用RT—PCR和基因扫描分析外周血或骨髓TCR Vβ24个亚家族基因的表达和克隆性,SSP—PCR检测HLA—DR。【结果】再障儿童外周血T细胞仅表达4—22个Vβ亚家族,而正常儿童外周血T细胞几乎表达所有Vβ亚家族。12例(包括初诊SAA4例,CR4例,复发1例和MAA3例)再障儿童存在不同程度T细胞克隆性增殖,但个体间差异较大,正常外周血和骨髓均为多克隆性T细胞。5例HLA—DRB1*15(+)患儿中4例(80%)有寡克隆T细胞,而12例HLA—DRB1*15(-)患儿中仅3例(25%)见寡克隆T细胞,两组比较差异具有显著意义(P〈0.05)。伴寡克隆T细胞的6例S从儿童经免疫抑制治疗后达CR;不伴寡克隆T细胞的5例SAA儿童接受免疫抑制治疗,其中CRI例,PR2例、无效1例,死亡1例。【结论】大多数再障儿童存在T细胞克隆性增殖,寡克隆T细胞多见于SAA,尤其是HLA—DRB1*15(+)的SAA儿童。TCR VβT细胞克隆的检测对进一步了解再障免疫功能状态、预测免疫抑制治疗效果具有一定的参考价值。  相似文献   
39.
HLA-DRB1等位基因在皖籍类风湿关节炎患者的分布   总被引:1,自引:0,他引:1  
目的探讨HLA-DRB1基因在皖籍类风湿关节炎患者的分布。以寻找皖籍类风湿关节炎患者的易感性和保护性HLA-DRB1等位基因及这些等位基因的意义。方法采集类风湿关节炎患者(106例)和正常对照(340例)外周静脉血,采用SSP多重PCR技术扩增两组成员HLA-DRB1等位基因。计算并比较两组等位基因携带率。结果HLA-DRB1*04、DRB1*09和DRB1*1001在RA组的频率显著高于正常对照组,两组差异有显著性(P〈0.01);而HLA-DRB1*11、DRB1*15和DRB1*07的频率显著低于对照组,两组差异有显著性(P〈0.01);其余等位基因在两组分布差异无显著性(P〉0.05)。结论HLA-DRB1*04、DRB1*09和DRB1*1001可能是皖籍RA患者的易感性等位基因,HLA—DRB1*11、DRB1*15和DRB1*07可能是保护性等位基因。  相似文献   
40.
目的研究云南籍汉族寻常型银屑病患者与HLADR基因多态性之间的关联性以及与链球菌相关联的云南籍汉族寻常型银屑病患者与HLA-DR基因多态性之间的关联性,研究HLA-DR基因对免疫应答的遗传调控是否可影响链球菌感染后银屑病的发病及临床表现,探讨链球菌感染与银屑病发病的免疫遗传机理及遗传学的分子基础.  相似文献   
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