Banerjee B, Wang X, Kelly K J, Fink J N, Sussman G L, Kurup V P
Allergy-Immunology Division of the Medical College of Wisconsin, Milwaukee 53226, USA.
J Immunol. 1997 Dec 1;159(11):5724-32.
Prohevein is one of the major allergens associated with latex allergy. In the present study, we identified IgE binding regions of prohevein, and expressed multiple IgE binding epitopes by selective cloning. These truncated polypeptides were then used to demonstrate IgE in the sera of patients. Decapeptides of prohevein were synthesized on derivatized cellulose membrane with an offset of one amino acid. The IgE reactivity of these linear peptides was evaluated separately using pooled sera from latex-allergic health care workers (HCW) and spina bifida (SB) patients. A total of 10 IgE binding epitopes representing unique as well as shared epitopes from both the N- and C-domains of the prohevein were identified. Recombinant polypeptides were constructed based on the identified epitopes, and clones carrying DNA fragments were overexpressed. These recombinant peptides were evaluated for IgE binding with sera from HCW, SB, and normal individuals. Recombinant prohevein, hevein, and the C-domain exhibited IgE binding in 84, 88, and 40% of HCW sera, respectively, as against reactivity of 84% with crude latex allergens. However, only 48% of the sera from SB patients showed IgE binding with recombinant prohevein, while 56 and 28% had reactivity with recombinant N- and C-domains, respectively. Among the three remaining recombinant peptides of the C-domain, only CA44-103 showed IgE binding with SB patients. The results of the present study suggest that linear IgE epitope analysis and construction of recombinant peptides increase the sensitivity and specificity of the immunodiagnosis of latex allergy and provide more information on the immunopathogenesis of hypersensitivity reaction mediated by type I allergy.
原橡胶素是与乳胶过敏相关的主要过敏原之一。在本研究中，我们鉴定了原橡胶素的IgE结合区域，并通过选择性克隆表达了多个IgE结合表位。然后使用这些截短的多肽来检测患者血清中的IgE。在衍生化的纤维素膜上合成原橡胶素的十肽，氨基酸偏移一个。使用来自乳胶过敏医护人员（HCW）和脊柱裂（SB）患者的混合血清分别评估这些线性肽的IgE反应性。总共鉴定出10个IgE结合表位，它们代表原橡胶素N端和C端结构域的独特表位以及共享表位。基于鉴定出的表位构建重组多肽，并使携带DNA片段的克隆过量表达。评估这些重组肽与HCW、SB和正常个体血清的IgE结合情况。重组原橡胶素、橡胶素和C端结构域分别在84%、88%和40%的HCW血清中表现出IgE结合，而与粗乳胶过敏原的反应性为84%。然而，只有48%的SB患者血清与重组原橡胶素表现出IgE结合，而分别有56%和28%的血清与重组N端和C端结构域有反应。在C端结构域的其余三个重组肽中，只有CA44 - 103与SB患者表现出IgE结合。本研究结果表明，线性IgE表位分析和重组肽的构建提高了乳胶过敏免疫诊断的敏感性和特异性，并为I型过敏介导的超敏反应的免疫发病机制提供了更多信息。
