Epitopes on Ki antigen and its association to autoantibody production.

Ki 抗原上的表位及其与自身抗体产生的关联。

• 批准号: 04670396
• 负责人: TAKASAKI Yoshinari
• 金额: $ 1.34万
• 依托单位: Juntendo University School of Medicine
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04670396/
• 关键词: Autoantibody; Autoantigen; Ki antigen; Molecular mimicry; epitope; 抗核抗体; ウイルス; ANA; cDNA; SLE; SV40large T antigen; 自時抗体

A cDNA coding for a nuclear autoantigen, Ki, has been cloned previously and we have found that Ki has an amino acid sequence which is homologous to SV 40 large T antigen nuclear localization sign (SV 40 NLS). We studied whether the amino acid sequence which is homologous to SV 40 NMS is one of the epitopes on Ki antigen and anti-Ki antibody croos-react with SV 40 large T antigen.Forty-nine anti-Ki positive sera were selected from 250 patients with systemic lupus erythematosus (SLE) by enzyme-linked immunosorbent assay (ELISA) using recombinant Ki (bNAX) as an antigne. A 16-mer Ki synthetic peptide that had a sequence homologous to SV 40 NLS (KILT) was prepared. In addition, 4 different synthetic peptides (KISP1-4) were prepared based on the analysis of conformational profile and hydoropathy of Ki antigen. The reactivities of anti-Ki sera to those synthetic peptides were tested by ELISA.Eighteen out of 49 sera reacted with KILT but none of them strongly reacted with KISP1-4. The KILT specifically reacted with anti-Ki sera but did not react with autoantibodies to other nuclear antigens such as U1 RNP,Sm, SS-A,SS-B,PCNA,Scl-70 and Jo-1. In addition, the reactivity of anti-Ki antibodies to KILT was specifically inhibited by bNAX.Those results indicated that KILT specifically reacted with anti-Ki antibody. A 7-mer synthetic peptide that had the same sequence as that of SV 40 NLS (LTSP) was prepared to test the cross-reactivity between the Ki antigen and SV 40 large T antigen. Eight out of 49 sera reacted with it and 7 of them reacted with both LTSP and KILT.The frequency of sera reacted with LTSP in anti-KILT positive sera (38.8%) was significantly higher (P<0.01) compared with that in anti-KILT negative sera (3.2%). Those results suggest that anti-Ki antibodies from lupus patients recognize the amino acid sequence homologous to SV 40 NLS as an epitope and molecular mimicry between Ki and SV 40 large T antigen may play a possible role for autoantibody production.

编码核自身抗原KI的cDNA已被克隆，我们发现KI含有一个与SV-40大T抗原核定位标志(SV-40 NLS)同源的氨基酸序列。为探讨与SV 40 NMS同源的氨基酸序列是否是与SV 40大T抗原发生交叉反应的KI抗原表位和抗KI抗体的表位之一，以重组KI(BNAX)为抗原，采用酶联免疫吸附试验(ELISA)从250例系统性红斑狼疮(SLE)患者中筛选出49份抗KI阳性血清。制备了一种与SV 40NLS(Kirt)序列同源的16聚KI合成肽。此外，通过对KI抗原的构象分析和杂化分析，制备了4种不同的合成肽(KISP1-4)。用ELISA检测了抗KI血清与合成肽的反应性，49份血清中有18份与KIRT反应，但没有一份与KISP1-4发生强烈反应。该短裙可与抗KI血清特异反应，但不与U1RNP、Sm、SS-A、SS-B、PCNA、SCL-70和Jo-1等核抗原自身抗体反应。此外，抗KIL抗体对KILT的反应性被bNAX特异性抑制，表明KILT与抗KI抗体发生了特异性反应。制备了一个与SV 40 NLS(LTSP)序列相同的7聚体合成肽，用于检测KI抗原与SV 40大T抗原的交叉反应。在49份血清中有8份与LTSP反应，其中7份同时与LTSP和KILT反应。抗kirt阳性血清与LTSP反应的频率(38.8%)显著高于抗kirt阴性血清(3.2%)(P&lt；0.01)。这些结果提示，狼疮患者抗KI抗体可识别与SV 40 NLS同源的氨基酸序列作为表位，KI与SV 40大T抗原之间的分子模拟可能对自身抗体的产生起作用。

项目成果

Takasaki Y,Yamanaka K,Nikaido T,Shimada K,Shibata M,Hashimoto H,Hirose S: "An epitope on Ki antigen recognized by autoantibodies from lupus patients is homologous to SV 40 large T antigen nuclear localization sign." Mol Biol Rep. 15. 216 (1991)

Takasaki Y、Yamanaka K、Nikaido T、Shimada K、Shibata M、Hashimoto H、Hirose S：“狼疮患者自身抗体识别的 Ki 抗原上的表位与 SV 40 大 T 抗原核定位标志同源。”

H Hashimoto,M Sugawara,Y Tok〓〓 M Sakamoto,Y Isobe,Y Takasaki,K Karasawa,I Hirose: "Follow up study of the changes in the clnical features and prognosis of Japanese patients with systemic lupus ery the matosus cluring the past 3to4 decades." J.Epidemiol.3.

H Hashimoto,M Sukawara,Y Tok〓 M Sakamoto,Y Isobe,Y Takasaki,K Karasawa,I Hirose：“日本系统性狼疮患者临床特征和预后变化的跟踪研究3 至 4 十年。”J.Epidemiol.3。

Takasaki,Y.,Yamanaka,K.,Nikaido,T.,Shimada,K.,Shibata,M.,Hashimoto,H.,and Hirose,S.: "An epitope on Ki antigen recognized by antoantibodies from lupus patients is homologous to SV40 large T antigen muclear localization sign" Molec.Biol.Rep.15. 216-216 (19

Takasaki,Y.、Yamanaka,K.、Nikaido,T.、Shimada,K.、Shibata,M.、Hashimoto,H. 和 Hirose,S.：“狼疮患者的抗体识别的 Ki 抗原上的表位是同源的

Hashimoto H,Sugawara M,Tokano Y,Sakamoto M,Isobe Y,Takasaki Yet al: "Follow up study of the changes in the clinical features and prognosis of Japanes patients with systemic lupus erytematosus during the 4 decades." J Epidemiol. 3. 19-27 (1993)

Hashimoto H，Sukawara M，Tokano Y，Sakamoto M，Isobe Y，Takasaki Yet al：“40年来日本系统性红斑狼疮患者临床特征和预后变化的跟踪研究”。

高崎芳成: "最新内科学大系24膠原病と類縁疾患、抗核抗体" 中山書店, 624 (1993)

高崎吉成：《最新内科24种胶原蛋白疾病及相关疾病、抗核抗体》中山书店，624（1993）