Immunodominant conformational and linear IgE epitopes lie in a single segment of Ara h 2.
Immunodominant conformational and linear IgE epitopes lie in a single segment of Ara h 2.
复制标题
免疫优势的构象和线性IgE表位存在于Arah2的单个片段中。
DOI：
10.1016/j.jaci.2021.12.796
复制
发表时间：
2022-07
影响因子：
14.2
通讯作者：
Bernard, Herve
中科院分区：
文献类型：
--
作者：
Hazebrouck, Stephane;Patil, Sarita U.;Guillon, Blanche;Lahood, Nicole;Dreskin, Stephen C.;Adel-Patient, Karine;Bernard, Herve
花生过敏原Ara h 2和Ara h 6的IgE反应性的构象表位的贡献至少与线性表位的贡献一样重要。然而，对这些构象IgE结合表位知之甚少。我们研究了嵌合2S-白蛋白上构象表位的分布。通过在Ara h 2和Ara h 6之间交换结构片段来产生重组嵌合体。通过圆二色性分析验证的良好重折叠的嵌合体然后用于通过进行IgG结合的竞争性抑制来确定mAb的表位特异性。此外，我们通过测量嵌合体与来自21名对花生过敏的患者的血清的IgE结合能力，描绘了每个片段对两种2S-白蛋白的总体IgE反应性的贡献。我们最后评估了嵌合体触发肥大细胞脱粒的能力。嵌合体中保留了构象表位的构型。针对天然Ara h 6产生的小鼠IgG mAb和多克隆人IgE抗体识别沿所有沿着Ara h 6分布的不同构象表位。相比之下，我们确定了人IgG单克隆抗体特异性不同的Ara h 2的线性或构象表位位于除C-末端的所有区段。Ara h 2的主要构象IgE结合表位位于残基33和81之间的片段中，该片段还包含主要的线性含羟脯氨酸的表位。因此，这段是关键的能力阿糖胞苷h 2诱导肥大细胞脱粒。嵌合2S-白蛋白提供了新的见解的构象IgE结合表位的Ara h 2和Ara h 6。免疫显性线性和构象IgE结合表位的接近可能有助于阿糖胞苷h 2的高致敏效力。
Contribution of conformational epitopes to the IgE reactivity of peanut allergens Ara h 2 and Ara h 6 is at least as important as that of the linear epitopes. However, little is known about these conformational IgE-binding epitopes. We investigated the distribution of conformational epitopes on chimeric 2S-albumins. Recombinant chimeras were generated by exchanging structural segments between Ara h 2 and Ara h 6. Well-refolded chimeras, as verified by circular dichroism analysis, were then used to determine the epitope specificity of mAbs by performing competitive inhibition of IgG binding. Furthermore, we delineated the contribution of each segment to the overall IgE reactivity of both 2S-albumins by measuring the chimeras’ IgE-binding capacity with sera from 21 patients allergic to peanut. We finally assessed chimeras’ capacity to trigger mast cell degranulation. Configuration of the conformational epitopes was preserved in the chimeras. Mouse IgG mAbs, raised against natural Ara h 6, and polyclonal human IgE antibodies recognized different conformational epitopes distributed all along Ara h 6. In contrast, we identified human IgG mAbs specific to different Ara h 2 linear or conformational epitopes located in all segments except the C-terminal one. The major conformational IgE-binding epitope of Ara h 2 was located in a segment located between residues 33 and 81 that also contains the major linear hydroxyproline-containing epitope. Accordingly, this segment is critical for the capacity of Ara h 2 to induce mast cell degranulation. Chimeric 2S-albumins provide new insights on the conformational IgE-binding epitopes of Ara h 2 and Ara h 6. Proximity of the immunodominant linear and conformational IgE-binding epitopes probably contributes to the high allergenic potency of Ara h 2.
登录
查看更多内容
影响因子：
14.2
作者：
Albrecht, Melanie;Kuehne, Yvonne;Vieths, Stefan
通讯作者：
Vieths, Stefan
影响因子：
4.1
作者：
Lehmann, K;Schweimer, K;Rösch, P
通讯作者：
Rösch, P
影响因子：
12.4
作者：
Bernard, H;Paty, E;Scheinmann, P
通讯作者：
Scheinmann, P
影响因子：
6.1
作者：
Koid AE;Chapman MD;Hamilton RG;van Ree R;Versteeg SA;Dreskin SC;Koppelman SJ;Wünschmann S
通讯作者：
Wünschmann S
影响因子：
4.3
作者：
Bernard, Herve;Drumare, Marie-Francoise;Wal, Jean-Michel
通讯作者：
Wal, Jean-Michel