Evaluation of recombinant fragments of entamoeba histolytica Gal/GalNAc lectin intermediate subunit for serodiagnosis of amebiasis
Evaluation of recombinant fragments of entamoeba histolytica Gal/GalNAc lectin intermediate subunit for serodiagnosis of amebiasis
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DOI：
10.1128/jcm.42.3.1069-1074.2004
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发表时间：
2004-03-01
影响因子：
9.4
通讯作者：
Takeuchi, T
中科院分区：
文献类型：
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作者：
Tachibana, H;Cheng, XJ;Takeuchi, T
我们最近鉴定了溶组织内阿米巴的150-kDa表面抗原作为半乳糖和N-乙酰基-D-半乳糖胺可降解凝集素的中间亚基（Igl），所述凝集素是由1，101个氨基酸（aa）组成并且在氨基酸序列中含有多个CXXC基序的富含半胱氨酸的蛋白质。在本研究中，全长Igl除了信号序列外，（aa 14 - 1088）和N-末端部分的三个Ig I片段（aa 14至382），中间部分（aa 294至753），和C-末端部分（aa 603至1088）-在大肠杆菌中制备，用酶联免疫吸附试验（ELISA）检测重组蛋白与阿米巴病患者血清的反应性。血清来自57例有症状的阿米巴肝脓肿或阿米巴结肠炎患者，血清来自15个无症状的囊肿传者，血清来自40个其他原生动物感染的个体，和血清来自50个健康对照。重组全长Igl在ELISA中的灵敏度和特异性分别为90%和94%。用这三个片段作抗原进行ELISA检测，N端的灵敏度为56%，中间部分为92%，C端为97%。三种抗原的特异性在N端为96%，在中间和C端片段均为99%。这些结果表明，Igl不仅在有症状的E. Igl的羧基端是阿米巴病血清学诊断的特别有用的抗原。
We have recently identified a 150-kDa surface antigen of Entamoeba histolytica as an intermediate subunit (Igl) of galactose- and N-acetyl-D-galactosamine-inhibitable lectin, which is a cysteine-rich protein consisting of 1,101 amino acids (aa) and containing multiple CXXC motifs in amino acid sequences. In the present study, full-length Igl except for the signal sequences (aa 14 to 1088) and three fragments of Igl-the N-terminal part (aa 14 to 382), the middle part (aa 294 to 753), and the C-terminal part (aa 603 to 1088)-were prepared in Escherichia coli, and the reactivity of these recombinant proteins with sera from patients with amebiasis was examined by means of enzyme-linked immunosorbent assay (ELISA). Sera from 57 symptomatic patients with amebic liver abscess or amebic colitis, sera from 15 asymptomatic cyst passers, sera from 40 individuals with other protozoan infections, and sera from 50 healthy controls were used. The sensitivity and specificity of the recombinant full-length Igl in the ELISA were 90 and 94%, respectively. When three fragments were used as antigens in the ELISA, the sensitivities were 56% in the N terminus, 92% in the middle part, and 97% in the C terminus. The specificities of the three antigens were 96% in the N terminus and 99% in both the middle and C-terminal fragments. These results demonstrate that Igl is well recognized in not only symptomatic but also asymptomatic patients with E. histolytica infection and that the carboxyl terminus of Igl is an especially useful antigen for the serodiagnosis of amebiasis.