中国汉族强直性脊柱炎患者人类白细胞抗原-B27多态性研究

目的 本研究拟利用最新的人类白细胞抗原(HLA)-B27亚型数据,调查中国汉族强直性脊柱炎(AS)患者HLA-B27及其亚型的分布情况.方法 从我院脊柱关节炎患者数据库中随机抽取100例AS患者.用luminex液态芯片,结合聚合酶链反应-序列特异性寡核苷酸探针(PCR-SSOP)技术对HLA-B位点作低分辨分型.HLA-B27阳性者进一步用聚合酶链反应-序列特异性引物(PCR-SSP)法做高分辨HLA-B27亚型检测.结果 经随机抽样纳入无关AS患者98例,其中HLA-B27阳性93例,阳性率94.9%,其中B*2704亚型76例(81.7%),B*2705亚型12例(12.9%),B*2715亚型5例(5.4%).与另外2篇文献报道的HLA-B27阳性汉族健康人群比较,没有一致的证据表明HLA-B27亚型分布在AS患者和健康人群中存在差异.但这2项汉族健康人群中的研究均未发现B*2715亚型.结论 中国汉族AS患者B27亚型以B*2704为主,其次是B*2705.B*2715作为一个频率极低的等位基因,本组病例中发现5例,提示B*2715与AS发病存在关联.     

利用噬菌体肽库筛选特异性哇巴因结合肽

目的寻找与哇巴因特异性结合的多肽,为实现阻断或拮抗哇巴因与钠泵的作用,减少EO致高血压作用奠定实验及理论基础.方法采用噬菌体随机肽库表面呈现技术筛选出哇巴因特异性结合肽,通过测序,获得氨基酸序列,进行同源性分析,合成筛选出的12肽,采用放射性配基受体结合法检测哇巴因结合肽与哇巴因的结合能力.结果从噬菌体12肽库中筛选出三种多肽,肽A(12肽)的筛选一致率达到66.7%(8/12);肽B(8肽,插入片段中出现终止子) 筛选一致率为16.7%(2/12);肽C(12肽)为8.3%(1/12);仅1例未见插入的多肽片段.Genbamk中蛋白质同源性分析结果肽A、B、C均未见同源蛋白.结论哇巴因特异性结合肽蛋白质序列的获得,为哇巴因的研究提供了实验基础.     

HLA-B*27及其亚型与强直性脊椎炎的相关性研究

目的:探讨人类白细胞抗原B*27(HLA-B*27)及其亚型与强直性脊柱炎(AS)患者发病的相关关系。方法:采用二重Taqman实时PCR方法检测23名AS就诊患者及其105名一级亲属的HLA-B*27,并采用高分辨的PCR-SSP技术分析HLA-B*27的亚型。结果:AS就诊患者HLA-B*27的阳性率为91.30%,其一级亲属HLA-B*27的阳性率为42.85%,患病率22.86%;3个家系的HLA-B*27亚型为HLA-B*2705,其他家系均为HLA-B*2704。结论:AS的发生与HLA-B*27密切相关,且具有家族遗传性;与HLA-B*2705比较,HLA-B*2704是发生AS更危险的因素。     

应用噬菌体随机肽库研究细粒棘球蚴抗原模拟表位

用抗细粒棘球蚴B抗原(EgB)多克隆抗体筛选噬菌体随机7肽库。经过5轮筛选后,噬菌体回收率从第1轮的4.15×10-5增加到第5轮的4.30×10-2,说明阳性克隆得到富集。随机挑取60个蓝色噬菌斑进行扩增,对其核苷酸序列进行测定分析并与EgB进行同源性比较。采用ELISA法对阳性噬菌体与抗EgB多克隆抗体结合特性进行检测,共检测出45个与抗EgB多克隆抗体结合的克隆株(阳性率为75%),其递呈的七肽序列与EgB的同源性低。采用ELISA法检测所选多肽对棘球蚴病所致过敏性休克患者抗血清的反应性,结果显示,细粒棘球蚴病患者抗血清与45个阳性噬菌体克隆反应的吸光度(A410值)比其与7肽库反应的A410值大2倍以上,该45个阳性噬菌体克隆与EgB多克隆抗体的结合是特异的。提示成功分析细粒棘球蚴囊液B抗原肽表位以及模拟表位。     

HLA-B27亚型与强直性脊柱炎的相关性研究

目的:研究重庆地区汉族人群的正常人和强直性脊柱炎(AS)患者的HLA-B27亚型基因分布的特点,分析HLA-B27亚型与AS发生的相关性.方法:采用PCR-SSP方法对重庆地区汉族人群中HLA-B27阳性的正常人126例和AS患者134例进行HLA-B27亚型的检测.结果:在正常组和AS组中,共检出了10种HLA-B27亚型,2组均以B*2704和B*2705亚型为优势亚型,2亚型分别为90%和95%.2组间的B*2704和B*2707亚型的构成比差异有统计学意义.B*2704亚型在AS患者组中的分布大于正常组,B*2707亚型在正常组的分布大于AS患者组.结论:B*2704亚型与AS呈正相关(OR=2.12,P＜0.05),为重庆地区汉族人群中的主要致病基因,而B*2707亚型与AS呈负相关(OR=0.11,P＜0.05),可能有保护性作用.     

噬菌体随机环7肽库筛选恶性疟原虫EBA-175的结合肽

目的从噬菌体随机环7肽库中筛选恶性疟原虫EBA175抗原的结合肽。方法以EBA175重组蛋白为靶筛选噬菌体随机环7肽库,通过ELISA、竞争抑制试验、Westernblot等方法鉴定获得的噬菌体短肽与EBA175之间的结合特性。对阳性克隆进行DNA序列测定,推导其氨基酸序列并与GPA氨基酸全序列进行了同源性比较。结果获得9株可与EBA175结合的阳性噬菌体克隆,序列分析显示为3种氨基酸序列,P1(MLLITIR)、P2(TRKLPRT)、P3(KRLMPLK)。其中出现频率最高的P1序列中LLI与EBA175的受体GPA的108110位氨基酸同源。竞争性ELISA显示展示序列P1的噬菌体能竞争抑制EBA175与其单抗的结合。结论获得了可与EBA175特异结合的阳性噬菌体短肽,·LLI··几位氨基酸可能对EBA175与GPA的结合起重要作用。     

恶性疟原虫感染的红细胞膜表面蛋白1模拟肽的筛选及鉴定

目的 筛选恶性疟原虫感染的红细胞膜表面蛋白1（PfEMP?鄄1）的噬菌体表位模拟肽。 方法 细胞间粘附分子ICAM-1模拟12肽（KLYLIAEGSVAA）能模拟ICAM-1分子与疟原虫感染红细胞结合的功能，以展示该短肽的噬菌体为靶，采用差减筛选法（subtraction method）对噬菌体环7肽库进行3轮筛选，通过ELISA、竞争抑制试验鉴定获得的噬菌体短肽与ICAM-1之间的结合特性。对阳性克隆进行DNA及氨基酸序列分析并与PfEMP-1氨基酸序列进行同源性比较。 结果 ELISA筛选22个克隆有3个为阳性克隆，氨基酸序列分析显示2个克隆的展示的短肽序列为C-ITAVPVR-C，另1为C-DIMGGYN-C。同源性分析未发现2短肽序列与野生型MC株恶性疟原虫PfEMP-1的氨基酸序列有同源性。但竞争抑制试验显示3个阳性克隆均可与15.2单抗间互相竞争抑制与ICAM-1分子的结合。 结论 获得2种PfEMP-1噬菌体构象表位模拟肽，两短肽能与ICAM-1分子特异性结合。     

利用噬菌体肽库筛选特异性哇巴因结合肽

目的 寻找与哇巴因特异性结合的多肽，为实现阻断或拮抗哇巴因与钠泵的作用，减少EO致高血压作用奠定实验及理论基础。方法 采用噬菌体随机肽库表面呈现技术筛选出哇巴因特异性结合肽，通过测序，获得氨基酸序列，进行同源性分析，合成筛选出的12肽，采用放射性配基受体结合法检测哇巴因结合肽与哇巴因的结合能力。结果 从噬菌体12肽库中筛选出三种多肽，肽A（12肽的筛选一致率达到66．7％（8／12）；肽B（8肽，插入片段中出现终止子）筛选一致率为16．7％（2／12），肽C（12肽）的筛选一致率达到66．7％（8／12），肽B（8肽，插入片段中出现终止子）筛选一致率为16．7％（2／12）；肽C／（12肽）为8．3％（1／12），仅1例未见插入的多肽片段。Genbamk中蛋白质同源性分析结果：肽A，B，C均未见同源蛋白。结论 哇巴因特异性结合肽蛋白质序列的获得，为哇巴因的研究提供了实验基础。     

用噬菌体展示随机7肽库筛选血型A抗原模拟肽

目的:通过血型A单克隆抗体从噬菌体展示随机7肽库中筛选血型A抗原的模拟多肽。方法:通过对噬菌体随机7肽库进行3轮亲和筛选,从第三轮筛选后获得的洗脱物中挑选多个噬菌体克隆,采用ELISA方法鉴定阳性克隆,测序并推导噬菌体展示短肽的氨基酸序列,化学合成短肽、红细胞凝集抑制试验鉴定短肽模拟A抗原的能力。结果:三轮筛选后特异性噬菌体被富集了200多倍,对ELISA鉴定信号较强的16个噬菌体克隆DNA测序并推导氨基酸序列的结果显示两个克隆展示相同的序列FSYLPSH。化学合成肽能抑制A型红细胞与抗A的凝集作用。结论:肽FSYLPSH具有模拟血型A抗原表位的作用,具有代替天然血型A抗原在临床中应用的潜能。     

噬菌体展示肽库在乳腺癌血清肿瘤标志物筛选中的应用

目的用噬菌体随机12肽库对乳腺癌患者的血清进行差异性筛选,以获得乳腺癌特异性的新的肿瘤标志物。方法对噬菌体随机12肽库进行三轮差异性筛选,用ELISA法测定噬菌体克隆对乳腺癌患者血清结合的特异性。结果经过三轮筛选,噬菌体富集率逐轮递增,经47例乳腺癌患者和正常人血清的ELISA法检测验证,获得一株与乳腺癌患者血清特异较好的噬菌体,经DNA测序和推导,其短肽序列为短肽(QVSAEHKVQGFW)。结论成功筛选到能与乳腺癌患者血清高亲和力特异结合的12肽序列,为今后研究乳腺癌肿瘤标志物奠定了基础。     

Modulation at multiple anchor positions of the peptide specificity of HLA-B27 subtypes differentially associated with ankylosing spondylitis.

OBJECTIVE: To investigate the rules governing peptide binding to HLA-B*2705, and to B*2704 and B*2706, which are 2 subtypes differentially associated with ankylosing spondylitis. METHODS: Poly-Ala analogs carrying the HLA-B27 motif Arg-2, and substitutions at anchor positions P1, P3, or Pomega, were used to determine a binding score for each residue at each position. Binding was assessed in a quantitative epitope stabilization assay, where the cell surface expression of HLA-B27 was measured by flow cytometry as a function of peptide concentration. RESULTS: Peptide anchor residues contributed additively to B*2705 binding. About 15% of the natural B*2705 ligands used a deficient P3 or Pomega anchor, but never both, indicating that detrimental anchoring at one of these positions is always compensated by a good anchor at the other one. About 50% of the B*2705 ligands used suboptimal P1 residues. However, this was compensated with optimal P3 and/or Pomega anchoring. Peptides that were longer than decamers used good anchor residues at the 3 positions, suggesting more stringent binding requirements. B*2704 and B*2706 differed in their residue specificity at P1, P3, and Pomega. The rules derived for B*2705 also applied to the known ligands of these 2 subtypes. CONCLUSION: The B*2705, B*2704, and B*2706 peptide repertoires are limited by the allowed residue combinations described in this study. The differential association of B*2704 and B*2706 with spondylarthropathy correlates with differences in their peptide specificity at multiple anchor positions. However, it is now possible to predict the peptide features that determine this differential binding to both subtypes.     

Subtypes of the HLA-B27 molecule and association with spondylarthropathies

HLA-B27 subtypes differ in their ethnic distribution and in their susceptibility to spondylarthropathies (SA). B*2705 and B*2702 are the most frequent disease-associated subtypes in Caucasians as well as B*2704 and B*2707 in Asia while B*2706 in Asia and B*2709 in Sardinia have been reported not to be associated to SA. Differences in antigenic peptide presentation could underlie such behavior. Several studies suggested that a Tyr C-terminal peptide anchor could be found preferentially in disease-associated subtypes and could be therefore one of the criteria in the search of putative arthritogenic peptide(s). We analyzed by HPLC and Edman sequencing peptides eluted from immunopurified HLA-B27 molecules expressed on B-lymphoblastoid cell lines or C1R transfectans of human origin. We focused our work on B*2707, associated with SA in the same geographical area where B*2706 is not. We found the same preference for Leu at the C-terminus in the peptides bound by both subtypes without any significant signal for Tyr. In the same experimental conditions a Tyr C-terminal anchor was found for B*2705, B*2702, B*2704, B*2703 and also for B*2701 and B*2708, 2 rare subtypes for which binding specificity was previously unknown. Comparison of the F-pocket aminoacid composition in these various subtypes showed a correlation between Asp at position 116 and Tyr at the peptide C-terminus. Asp116 is changed for Tyr in B*2706, B*2707 and His in B*2709, all subtypes allowing a Leu C-terminal anchor. Therefore a Tyr C-terminal anchor correlates with the HLA-B27 F-pocket composition rather than with susceptibility to SA.     

The association of HLA-B*27 subtypes with ankylosing spondylitis in Wuhan population of China

The aim of this study was to investigate the association of the B27 subtypes with ankylosing spondylitis (AS) in the Wuhan population of China. We selected 317 HLA-B27-positive individuals (145 controls and 172 patients with ankylosing spondylitis). The B27 subtypes were characterized using a PCR-SSP method. Six B27 subtypes were determined: B*2702, 03, 04, 05, 06 and B*13. HLA-B*2704 and HLA-B*2705 were the two high frequency genotypes in controls and patients. Compared with the controls, the AS patients had high frequency of B*2704 (patients 69.2% vs. controls 53.8%) and low frequency of B*2705 (patients 23.8% vs. controls 33.1%). B*2703 was detected in 10 (5.8%) patients and in 13 (8.9%) controls. B*2702, 06 and B*2713 were relatively rare. Our results show that the allele conferring risk to AS in the Wuhan population of China was B*2704 and B*2705. B*2704 is strongly associated with AS.     

幼年强直性脊柱炎临床特点和HLA-B27亚型的相关性研究

目的提高对幼年强直性脊柱炎(JAS)和HLA-B27亚型相关性的认识。方法分析检测55例JAS患儿HLA-B27亚型和临床特点。采用国际标准微量淋巴细胞毒实验法进行血清学分型。DNA分型采用聚合酶链反应-序列特异引物技术(PCR-SSP)检测出B2701-B2713等位基因亚型。DNA提取取受测对象外周静脉血3ml,5%乙二胺四乙酸(EDTA)抗凝,饱和醋酸钠盐析法制备基因组DNA,PCR-SSP方法扩增。详细记录病史、家族史、全面体格检查,包括临床症状、体征、关节及关节外表现,相关影像学及实验室检查,随访1~5年。结果55例JAS患儿中B2704阳性者27例,B2705阳性者25例,B2702、B2707/2708及B2705/2708各1例。B2705阳性组36%(9/25)患儿关节肿痛伴发热,其中68%(17/25)存在外周关节炎,36%(9/25)为多关节炎,71%(17/24)CT显示骶髂关节病变为2级以上改变。B2704阳性组仅表现为关节肿痛,均无发热,74%(20/27)存在外周关节炎,其中有15%(4/27)为多关节炎表现,32%(8/25)CT显示骶髂关节病变2级以上改变。经统计学分析骶髂关节病变HLA-B2704组和B2705组之间差异有显著性(P<0.005)。结论JAS临床表现因HLA-B27亚型分布不同各有特点,等位基因B2705阳性患儿除关节症状外更易同时伴有发热,预后较等位基因B2704阳性患儿差。     

Human leukocyte antigen-B*2705 is the predominant subtype in the Korean population with ankylosing spondylitis,unlike in other Asians

This study was performed to investigate the frequency of human leukocyte antigen (HLA)-B27 subtypes in the Korean population with spondyloarthropathy (SpA). We determined the HLA subtypes of 267 SpA patients who were positive for the B27 antigen (as determined by serology) by using a PEL-FREEZ kit (Dynal Biotech, Wisconsin, USA). Clinical features, including sex, peripheral joint involvement, and the presence of uveitis, were analyzed in a retrospective cohort study. Among 267 patients, 244 were B*2705-positive and 22 were B*2704-positive. One patient was positive for B*2704/2705. No other subtype was observed among the analyzed patients. We found that HLA-B*2705 was the predominant subtype in Koreans with SpA; this finding is remarkable because other Asians such as the Han or the Japanese exclusively have the B*2704 subtype. This result suggests that the clinical features and prevalence of SpA in Koreans may be similar to those observed in Europeans.     

Evidence that HLA-B*2706 is not protective against spondyloarthropathy.

OBJECTIVE: Studies in Southeast Asia showed that HLA-B*2704 is positively associated with spondyloarthropathy (SpA), while B*2706 does not occur in such patients. In view of the absence of an association between B*2706 and SpA it was suggested that B*2706 protects against the disease, while it is supposed that B*2704 presents pathogenetic peptides. We studied families in which both B*2704 and B*2706 occurred to see whether in B*2704/B*2706 heterozygotes the effect of one of the subtypes shows a preponderance over the other. METHODS: Two families of mixed Chinese/Indonesian origin were studied. HLA-B27 subtyping was performed by polymerase chain reaction in combination with sequence specific oligonucleotide probes. RESULTS: In one family, members with B*2704, B*2706, or both occurred. In the other family B*2704, B*2706, and B*2708 were present. In both families SpA was seen only in B*2704 positive members, while the B*2706 and B*2708 positive members were healthy, except some B*2704/B*2706 or B*2704/B2708 heterozygotes. CONCLUSION: The pathogenic influence of B*2704 is thus dominant over the supposed protective influence of B*2706. It is probable that B*2704 can present pathogenetic peptides, while a protective influence of B*2706 does not exist. B*2708, which was until now described in only a few cases, behaved in this study as B*2706 and is probably not associated with SpA.     

Positive association of ankylosing spondylitis with homozygous HLA-B2704, but protection with B2705 in Taiwan Chinese

The study was undertaken to determine the effects of HLA-B27 subtypes on susceptibility to ankylosing spondylitis (AS) in Taiwan Chinese, a polymerase chain reaction-restrictive fragment length polymorphism (PCR-RFLP) method was developed for subtyping of HLA-B27. In this series, there are 62 patients with AS who were tested HLA-B27 positive serologically and 738 normal persons over the age of 65. Among the 738 normal controls, 42 (5.7%) were HLA-B27 positive. There were six (14.3%) homozygous for B2704, 18 (42.9%) heterozygous for B2704, 2 (4.8%) double heterozygous for B2704 and B2705, one (2.3%) double heterozygous for B2704 and B2706, 2 (4.8%) homozygous for B2705, 11 (26.1%) heterozygous for B2705, and 2 (4.8%) heterozygous for B2706. In our patients with AS, 37 (59.7%) were homozygous for B2704 and 25 (40.3%) were heterozygous for B2704. The HLA-B27 carrier rate in Taiwan healthy old persons is estimated at 5.7%. Susceptibility to AS is determined by homozygosity for B2704. However, B2705 may be an indicator of protection against AS in Taiwan Chinese.     

HLA-B27 subtypes in Turkish patients with ankylosing spondylitis and healthy controls

The aim of this study was to determine human leukocyte antigen (HLA)-B27 subtypes frequency in ankylosing spondylitis (AS) and related spondyloartropathy (SpA) patients. Therefore, we investigated the differences in HLA-B27 subtypes between HLA-B27-positive patients and controls. Sixty six patients were included in this study (51 AS and 15 SpA). Thirty-five individuals were diagnosed with leukemia or chronic renal failure, and their donors without any rheumatological problem (no SpA history) were selected as the control group. HLA-B27 subtyping was performed by PCR-SSP (polymerase chain reaction with sequence-specific primer) method in serologically HLA-B27-positive 46 AS patients, 9 SpA patients and control group. When the frequency of HLA-B27 was 4.5% in Turkish population, this frequency was 90.2% in AS patients. Four different HLA-B27 subtypes found in AS patients were B*2705 (65.2%), B*2702 (26.1%), B*2704 (6.5%) and B*2707 (2.2%). In SpA patients, B*2705 and B*2702 found in equal frequency. Five B27 alleles were identified in our control group: B*2705 (54.3%), B*2702 (31.4) %, B*2703 (2.9%), B*2704 (2.9%) and B*2702/B*2705 (8.5%). Both in the patient group and in the control group, we also observed B*2705 as most frequent allele, and B*2702 was second common allele. Our results show that the frequency of HLA-B27 subtypes is not significantly different between patients and controls (P?>?0.10).     

Correlation of HLA B27 subtypes with clinical features of ankylosing spondylitis

Aim: The aim of the present study was to identify the B*27 subtypes associated with ankylosing spondylitis (AS) in our population and correlate them with clinical features of AS. Method: Whole blood samples were collected from 81 HLA‐B27 positive AS patients and 29 controls (asymptomatic healthy unrelated individuals) positive for HLA‐B27. Clinical details of the patients were recorded which included history of inflammatory back pain, sacroiliitis, spine involvement, enthesitis, peripheral arthritis and uveitis. HLA‐B27 subtypes were detected using commercially available techniques. Fisher’s exact test was used for statistical analysis. Results: The subtypes observed in AS patients were B*2705 (67.9%, 55/81), B*2704 (28.4%, 23/81), B*2707 (2/81) and B*2702 (1/81). Subtypes in the controls were B*2705 (62.07%, 18/29), B*2707 (27.59%, 8/29) and B*2704 (10.34%, 3/29). Uveitis was observed more in B*2704‐positive AS patients (34.78%, 8/23) compared to B*2705‐positive AS patients (16.36%, 9/55). However, the difference was not statistically significant (P = 0.130). No major differences were found between B*2705 and B*2704 for other clinical features. Conclusion: B*2705 was the main subtype observed in both patient and control groups. Frequency of B*2704 was more in AS patients compared to controls. Occurrence of AS‐associated uveitis was more often in B*2704‐positive AS patients compared to B*2705‐positive ones.