MHC研究近况

免疫反应的基因调控是现代免疫学发展的一个重要方面,在近几年内进展十分迅速。直到60年代末人们才开始承认免疫应答基因位于主要组织相容性复合体(MHC)上,也就是人类白血病抗原HLA,小鼠的H-2复合体。     

昆明白族儿童HLA-DRB1、DQB1位点基因多态性分析

主要组织相容性复合体（MHC）是染色体上的一群紧密连锁的基因群，可作为一个遗传单彰单倍型而遗传，属共显性等位基因。人类的MHC称人类白细胞抗原（HLA）系统，位于人的第6对染色体短臂上。HLA-DR、DQ抗原是异基因移植免疫反应中最重要的抗原之一，决定其特异性的主要编码基因DRB1、DQB1具有高度多态性，其对HLA与疾病相关性及人类遗传学等研究均具有重要意义。     

沈阳地区汉族人群HLA-DRB1的PCR-SBT分型研究

HLA(humanleukocyteantigen ,HLA)位于人类第 6号染色体短臂 6p2 1.3区域 ,具有高度的遗传多态性 ,作为个体组织细胞的遗传标志物 ,在抗原识别、递呈、免疫应答与调控等方面起着非常重要的作用。其中HLA DR抗原是异基因移植免疫反应中最重要的抗原之一 ,决定其特异性的主要编码基因DRB1座位具有高度多态性 ,DRB1基因分型对器官移植的供体选择、法医学个体认定、HLA与疾病相关性及人类学等研究均具有重要意义。我们用聚合酶链反应 直接测序方法 (PCR SBT)对沈阳地区汉族健康个体进行了DRB1高分辨率的等位基因分析。沈阳地区汉族…     

慢性乙型肝炎与HLA-A和DRBl基因关联研究

乙肝病毒(HBV)的清除和预后转归在很大程度上取决于宿主的免疫应答。人类白细胞抗原(HLA)复合体是调节机体免疫应答的重要基因群，为此，我们利用基因芯片技术分析了上海地区慢性乙型肝炎患者HLA Ⅰ类中的A位点与HLA Ⅱ类中的DRB1位点的基因分布，以探索乙型肝炎慢性化与HLA-A和HLA-DRB1的可能关联。     

MHC基因多态性和肿瘤的发生

人类主要组织相容性复合物 (MHC)是一段约 3 6Mb的染色体区段 ,有 2 2 0多个基因位点 ,其中人类白细胞抗原(HLA)等位基因超过 2 0 0 0个 ,是迄今所知最复杂、多态态最高的遗传系统。几乎所有的HLA等位基因编码的蛋白质的差别都集中分布在其与抗原肽结合的分子凹槽中。这种差别决定了与抗原肽的结合强度 ,进而影响抗原肽的提呈 ,可能是肿瘤易感性的遗传基础之一。以病原微生物感染为诱因的肿瘤、非病原生物直接引起基因或染色体结构变化等原因导致的肿瘤 ,在与HLA等位基因的易感性上可能存在不同的机制。HLA等位基因的遗传易感性还与人种的遗传背景有关。由于技术上的原因 ,目前MHC多态性与肿瘤的遗传易感性研究主要集中在HLAII类等位基因或单倍型。HLAI类及其他MHC区域多态基因的等位基因与肿瘤易感性的研究值得关注。MHC有大量人群频率不一的等位基因和位点之间很强的连锁不平衡 ,要确定HLA等位基因与肿瘤发生的关系仍有困难 ,家系分析、群体规模的受累姊妹配对分析可获取更多信息。MHC单倍型和SNP分析相结合有利于准确分析MHC区域基因和肿瘤的关系 ,并鉴定和分析MHC中的新基因。理解MHC遗传多态性与肿瘤易感性对肿瘤的生物治疗有指导意义。     

用PCR-RFLP方法探讨人红白血病细胞系HLAⅡ基因型

在免疫应答和免疫调节中人类白细胞抗原 (HLA)起着至关重要的作用。目前研究指出 :HLA抗原与人类疾病的发生、发展以及预后有着密切的关系。HLA抗原与疾病关联的最可能机理是存在某些与HLA紧密连锁并处于连锁不平衡的免疫反应基因或疾病易感基因。红白血病细胞系 (humanerythorleu kemiacellline,HEL)是 1981年建立的 ,该细胞系的特征是持续产生血红蛋白 ,主要Gγ和Aγ链 ,胎儿期球蛋白链和α链很少 ,不产生 β链 ,是红系细胞分化和球作者单位 :10 0 0 5 0首都医科大学附属北京友谊医院移植配型中心 (李志祥 ) ,血液内科 (谢桂岚 )通…     

人类白细胞抗原复合体与HBV感染的相关性研究进展

乙型肝炎是全球性公共卫生问题,据估计世界约有20亿人口曾感染乙肝病毒(hepatitis B virus,HBV),其中约4亿人发展为慢性,每年有600 000至1 200 000人死于HBV的感染[1].HBV感染后形成复杂的疾病谱,如亚临床感染、轻重程度不等的急性肝炎、慢性乙型肝炎(chronic hepatitis B,CHB)、肝硬化(liver cirrhosis,LC)和肝细胞癌(Hepatic cell carcinoma,HCC)等[2],具体形成机制尚不完全清楚,但环境、病毒(病毒载量、基因型、病毒变异)、宿主(健康状况、免疫特性)等被认为是影响HBV感染后病情进展的关键因素,尤其是宿主的免疫特性.人体免疫特性受主要组织相容性复合体(major his-tocompatibility,MHC)调控,此基因是编码人类白细胞抗原复合体(human leukocyte antigen,HLA)的机密连锁基因组,其具有向抗原特异性受体传递抗原多肽的特性,在免疫应答、免疫调控、破坏外来抗原等方面起重要作用[3].有关HLA基因多态性与HBV感染的临床转归国内外已进行了大量相关研究,但重复性较差,至今尚无定论,此领域仍有待进一步深入研究.本文就目前国内外研究现状作一简要综述.     

乙型病毒性肝炎与宿主遗传因素

乙型病毒性肝炎的发病与人类宿主遗传因素密切相关,本文就乙型病毒性肝炎与人类基因组关系进行综述,包括免疫反应相关的人类白细胞抗原(HLA)、维生素D受体(VDR)基因、甘露糖结合蛋白(MBP),此外肿瘤坏死因子-α(TNF-α)启动子基因的多态性,16q24.3基因不平衡等也与乙型病毒性肝炎相关.宿主遗传因素在乙型病毒性肝炎中起重要作用,涉及机体对病毒免疫应答的全过程.     

慢性乙型肝炎与HLA-A和DRB1基因关联研究

乙肝病毒 (HBV )的清除和预后转归在很大程度上取决于宿主的免疫应答。人类白细胞抗原 (HLA )复合体是调节机体免疫应答的重要基因群 ,为此 ,我们利用基因芯片技术分析了上海地区慢性乙型肝炎患者HLAI类中的A位点与HLAII类中的DRB1位点的基因分布 ,以探索乙型肝炎慢性化与HLA A和HLA DRB1的可能关联。1　材料与方法1 1　研究对象　上海曙光医院肝炎科住院和门诊慢性乙型肝炎患者全血标本 5 6例 ,其中 ,男 30例 ,女 2 6例 ,年龄2 5～ 75岁 ,符合 2 0 0 0年 9月西安中华医学会传染病与寄生虫病学分会 ,肝病学分会联合修订的《病毒…     

中国河南汉族HLA-DQB1基因多态性的群体调查

HLA即人类白细胞抗原(Human leucocyte antigen,HLA),是具有高度多态性的同种异体抗原,存在于人体的各种有核细胞表面,能识别"自己"和"非己",并通过免疫反应排除"非己",从而保持个体完整性。HLA分为Ⅰ类和Ⅱ类两大类抗原。HLA-DQ基因位于第六号染色体短臂的p21.3区域中,属于HLAⅡ类抗原,由α和β肽链组成,其中β     

HLA-DRB1, -DQA1, -DQB1, -DPA1 and -DPB1 genes in Japanese multiple sclerosis patients

Japanese MS patients and controls were examined for the distribution of HLA-DRB1, -DQA1, -DQB1, -DPA1 and -DPB1 alleles using in vitro amplification of genomic DNA and probing with sequence-specific oligonucleotides. No significant difference in frequency of the examined alleles was observed among the two groups. This is in contrast to Norwegian MS patients, where an association to a combination of certain DQA1 and DQB1 alleles has previously been demonstrated.     

NDE1 and NDEL1: Multimerisation,alternate splicing and DISC1 interaction

Nuclear Distribution Factor E Homolog 1 (NDE1) and NDE-Like 1 (NDEL1) are highly homologous mammalian proteins. However, whereas NDEL1 is well studied, there is remarkably little known about NDE1. We demonstrate the presence of multiple isoforms of both NDE1 and NDEL1 in the brain, showing that NDE1 binds directly to multiple isoforms of Disrupted in Schizophrenia 1 (DISC1), and to itself. We also show that NDE1 can complex with NDEL1. Together these results predict a high degree of complexity of DISC1-mediated regulation of neuronal activity.     

韩国人CYP450 1A1、CYP450 2E1和GSTM1、GSTT1、GSTP1基因座遗传多态性分析

目的 调查代谢相关的CYP4501A1、CYP4502E1和GSTM1、GSIT1、GSTP1基因座在韩国人群中的遗传多态性分布状况。方法 采用多重聚合酶链式反应、聚合酶链式反应-限制性片段长度多态性技术，分析300名韩国健康大学生的CYP1A1基因3′端限制性内切酶Msp Ⅰ位点、CYP2E1基因5′端转录调节区Pst Ⅰ位点和GSTM1、GSTT1缺失与存在、GSTP1基因第5外显子BsmA Ⅰ位点的基因型，计算基因型和基因频率。结果 CYP1A1基因型频率为ml／ml型39．7％、ml／m2型49．7％、m2／m2型10．7％，基因频率为ml 0．645、m2 0．355。CYP2E1基因型频率为cl／cl型66．7％、cl／c2型30％、c2／c2型3．3％，基因频率为C1 0．818、C2 0．182。GSTM1基因缺失型频率为53．3％。GSTT1基因缺失型频率为54．7％。GSTP1基因型频率为Ile／Ile型62％、Ile／Val型34．3％、VaL／Val型3．7％，基因频率为Ile 0．792、Val 0．208。基因分布符合Hardy-Weirtberg平衡定律。结论 韩国人CYP1A1、CYP2E1、GSTM1、GSTT1基因分布与我国人群较为相近，半数以上人缺乏GSTM1和GSTT1基因，纯合缺失型频率超过印度人的3倍。     

Maternal genetic polymorphisms in CYP1A1, GSTM1 and GSTT1 and the risk of hypospadias

Hypospadias is one of the most common congenital anomalies. Increased exposure to environmental factors (endocrine-disrupting chemicals and smoking) or maternal endogenous estrogen may cause hypospadias because male sexual differentiation is dependent on normal androgen homeostasis. Moreover, interactions between genetic factors and cigarette smoking and other chemicals have been suggested. It has been demonstrated that the CYP1A1 metabolizes not only environmental chemicals but also estrogens, and glutathione-S-transferases (GSTs) are detoxification enzymes that protect cells from toxicants by conjugation with glutathione. In this study, to investigate the association of CYP1A1 (MspI), GSTM1 and GSTT1 polymorphisms with hypospadias, a case-control study of 31 case mothers who had boys with hypospadias and 64 control mothers was performed in Japan. These polymorphisms were investigated by PCR-based methods using DNA from peripheral lymphocytes. We found that the heterozygous CYP1A1 and heterozygous and homozygous CYP1A1 were less frequent in the case mothers than in the control mothers [adjusted odds ratio (OR)=0.17, 95% confidence interval (CI)=0.04-0.74, OR = 0.28, 95% CI = 0.08-0.97, respectively]. We found no effect of maternal smoking on the hypospadias risks among the gene polymorphisms. The results suggest that mothers with the CYP1A1 MspI variant allele may have a decreased risk for hypospadias.     

Rb1cc1 is critical for myoblast differentiation through Rb1 regulation

Rb1-inducible coiled-coil 1 (Rb1cc1) expressed at high levels is associated with the maturation of human embryonic musculoskeletal cells. To clarify the molecular role of Rb1cc1 in muscular differentiation, we investigated the expression of Rb1cc1 and other genes that regulate differentiation in murine embryonic tissues and in C2C12 myoblasts. We also evaluated the effects of RNA interference (RNAi)-mediated Rb1cc1 knockdown on C2C12 myoblast differentiation. After Rb1cc1, Rb1 and myosin heavy chain (Myhc) were expressed in mouse embryonic muscles. The synchronous expression of Rb1cc1 and Rb1 predicted Myhc expression during C2C12 myoblast differentiation. RNAi-mediated knockdown of Rb1cc1 led to Rb1 suppression, and C2C12 myoblasts failed to differentiate. These results indicated that Rb1cc1 is a potent regulator of the Rb1 pathway and a novel mediator that plays a crucial role in muscular differentiation. Rb1cc1 expression is, thus, a prerequisite for myogenic differentiation.     

神经系统RNA结合蛋白Musashi1 RRM1的初步结晶

目的 对Musashi1发挥功能的 RRM1结构域进行结晶,得到可用来衍射的蛋白晶体,为之后的结构解析打基础。方法 通过构建Musashi1RRM1的原核表达载体,并在BL21中表达、纯化高纯度的蛋白质,通过筛选结晶体条件得到蛋白晶体。结果 通过系统筛选和优化晶体生长条件得到了蛋白晶体。结论 Musashi1 RRM1的蛋白晶体质量较好,满足蛋白晶体衍射和数据收集的要求。     

Circulatinglong non-coding RNA FEZF1-AS1 and AFAP1-AS1 serve as potential diagnostic biomarkers for gastric cancer

BackgroundGrowing evidence indicates that two long non-coding RNAs (lncRNAs), FEZ family zinc finger 1 antisense RNA 1 (FEZF1-AS1) and Actin filament associated protein 1 antisenseRNA1 (AFAP1-AS1), are highly expressed in different cancers, including gastric cancer (GC). However, the expression pattern and clinical utility of these two lncRNAs are still unknown.MethodsSerum expression levels of FEZF1-AS1 andAFAP1-AS1 were measured by quantitative real-time polymerase chain reaction (qRT-PCR). CEA and CA19-9 were detected by ARCHITET I2000 SR. Analyses were all performed using SPSS software version 20.0 (SPSS Inc., Chicago, USA). P < 0.05 was considered statistically significant.ResultsDetection of serum FEZF1-AS1 and AFAP1-AS1 showed both of them were up-regulated in GC patients compared with the normal controls (p < 0.0001), and high serum expression levels were correlated with tumor size, tumor-node-metastasis (TNM) stage and lymph node metastasis. Besides, the area under the ROC curve (AUC) demonstrated the two lncRNAs had higher diagnostic utility than CEA and CA19-9. Furthermore, when combined the two lncRNAs as a model, it yielded an AUC of 0.866, and the combination of the model, CEA and CA19-9 could observably improve diagnostic sensitivity to 95.5 %. What’s more, circulating FEZF1-AS1 and AFAP1-AS1 were significantly decreased after the GC patients underwent the operation (both p < 0.001).ConclusionOur study indicated that serum FEZF1-AS1 and AFAP1-AS1 had better sensitivity and efficiency for the diagnosis of GC and the combination of the two lncRNAs might be used as a potential prognostic indicator in GC.     

HIV-1 Nef stabilizes AP-1 on membranes without inducing ARF1-independent de novo attachment

HIV-1 Nef affects the trafficking of numerous cellular proteins to optimize viral replication and evade host defenses. The adaptor protein (AP) complexes, which form part of the cytoplasmic coat of endosomal vesicles, are key cellular co-factors for Nef. Nef binds these complexes and alters their physiologic cycle of attachment and release from membranes. Specifically, while AP-1 normally becomes cytosolic when attachment events are blocked by inhibition of the GTPase cycle of ADP-ribosylation factor-1 (ARF1), the complex remains membrane-associated in Nef-expressing cells. To investigate the mechanism of this effect, we used a permeabilized cell system to detect the de novo attachment of exogenous AP-1 to endosomal membranes. Nef did not mediate de novo attachment independently of ARF1, despite its ability to maintain the association of AP-1 with endosomal membranes when the activity of ARF1 was blocked. We conclude that Nef stabilizes AP complexes on endosomal membranes after ARF1-dependent attachment. This stabilization may facilitate coat formation and stimulate the trafficking of multiple cellular proteins.     

Ah receptor, CYP1A1, CYP1A2 and CYP1B1 gene polymorphisms are not involved in the risk of recurrent pregnancy loss

The etiology of recurrent pregnancy loss (RPL) remains unclear, but it may be related to a possible genetic predisposition together with involvement of environmental factors. We examined the relation between RPL and polymorphisms in four genes, human aryl hydrocarbon (Ah) receptor, cytochrome P450 (CYP) 1A1, CYP1A2 and CYP1B1, which are involved in the metabolism of a wide range of environmental toxins and carcinogens. All cases and controls were women resident in Sapporo, Japan and the surrounding area. The Ah receptor, CYP1A1, CYP1A2 and CYP1B1 genotypes were assessed in 113 Japanese women with recurrent pregnancy loss (RPL) and 203 ethnically matched women experiencing at least one live birth and no spontaneous abortion (control). No significant differences in Ah receptor, CYP1A1, CYP1A2 and CYP1B1 genotype frequencies were found between the women with RPL and the controls [Ah receptor: Arg/Arg (reference); Arg/Lys and Lys/Lys, odds ratio (OR)=0.67; 95% confidence interval (CI)=0.40-1.11, CYP1A1: m1m1 (reference); m1m2 and m2m2, OR = 0.86; 95% CI = 0.53-1.40, CYP1A2: C/C and C/A (reference); A/A, OR = 1.16; 95% CI = 0.71-1.88, CYP1B1: Leu/Leu (reference); Leu/Val and Val/Val, OR = 1.18; 95% CI = 0.68-2.02]. The present study suggests that the Ah receptor, CYP1A1, CYP1A2 and CYP1B1 gene polymorphisms are not major genetic regulators in RPL.     

IL—1受体相关激酶—1和—2协同调控IL—1诱导的AP—1的活化

目的研究白介素 - 1受体相关激酶 - 1(IRAK- 1)和 IRAK- 2在白介素 - 1(IL - 1)诱导 AP- 1活化中的作用。方法L ipofectin介导反义 IRAK- 1寡核苷酸和反义 IRAK- 2寡核苷酸转染 Hep G2细胞。用逆转录 PCR法检测 IRAK - 1和 IRAK- 2m RNA表达水平 ;Western blot分析 IRAK- 1和 IRAK - 2蛋白表达水平。以 Sandwich EL ISA法检测 AP- 1的活化。结果反义IRAK- 1寡核苷酸和反义 IRAK- 2寡核苷酸通过抑制各自靶基因 m RNA和蛋白表达抑制 IL- 1诱导的 AP- 1活化 ;反义 IRAK-1寡核苷酸与反义 IRAK- 2寡核苷酸共转染 Hep G2细胞对 AP- 1的抑制作用较两者单独转染明显增强。结论 IRAK- 1和 I-RAK- 2在调控白介素 - 1诱导的 AP- 1活化时协同作用。