Haptenic adducts of ß-lactam antibiotics elicit antibody responses with narrow clonality and specificity
Haptenic adducts of ß-lactam antibiotics elicit antibody responses with narrow clonality and specificity
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β-内酰胺抗生素的半抗原加合物引发具有窄克隆性和特异性的抗体反应
DOI：
10.1101/2023.11.02.565155
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Deimel L
中科院分区：
文献类型：
--
作者：
Deimel L
许多种类的小分子药物在体内形成蛋白加合物，这可能通过经典的半抗原载体型反应引发抗体，对过敏和药物螯合都有影响。虽然β-内酰胺抗生素是与这些现象长期相关的药物类别，但药物-蛋白质结合的分子决定因素和随后的药物特异性免疫应答仍然不完整。在这里，我们询问了影响青霉噻唑加合物形成和免疫原性的因素，并使用青霉素G（PenG）来探测小鼠中药物特异性IgG应答的B和T细胞决定簇。我们通过深克隆分型鉴定了一个占优势的鼠青霉噻唑特异性克隆抗体类，包括遗传相关的IGHV 1、IGHV 5和IGHV 10亚组基因片段。通过蛋白质NMR和X-射线结构分析，我们确定加合物特异性抗体克隆-MIL系列-主要通过疏水口袋识别可变侧链部分（对于PenG是苯基乙酰胺），而与噻唑烷和加合物赖氨酸残基的二级H-键接触。因此，与其他β-内酰胺抗生素的交叉反应性有限。这些数据证明了蛋白质反应性药物（如青霉素）的化学性质之间的关系，以及它们产生B细胞反应的倾向如何在克隆水平上告知功能性影响。Highlights-PenG在生理条件下容易在各种自体和非自体蛋白（包括完全血清）的赖氨酸侧链上形成免疫原性加合物。PenG-蛋白在体外或体内的加合足以引发青霉素特异性IgG应答。小鼠B细胞克隆型应答的特征在于具有相似免疫遗传起源的接近一致的抗体结合模式。占主导地位的小鼠PenG特异性克隆型主要由苯环识别，并与血清学交叉反应性特征相关。
Many classes of small-molecule drugs form protein adductsin vivo, which may elicit antibodies via a classical hapten-carrier-type response, with implications for both allergy and drug sequestration. Although β-lactam antibiotics are a drug class long associated with these phenomena, the molecular determinants of drug-protein conjugation and consequent drug-specific immune responses remain incomplete. Here, we interrogated factors influencing penicilloyl adduct formation and immunogenicity, and used penicillin G (PenG) to probe the B and T cell determinants of drug-specific IgG responses in mice. We identify through deep clonotyping a dominant murine penicilloyl-specific clonal antibody class encompassing phylogenetically relatedIGHV1,IGHV5andIGHV10subgroup gene segments. Through protein NMR and x-ray structural analysis, we determined that adduct specific antibody clones—the MIL series—predominantly recognise the variable side-chain moiety (which for PenG is phenylacetamide) via a hydrophobic pocket, while secondary H-bond contacts with both thiazolidine and the adducted lysine residue is made. As a result, the cross-reactivity against other β-lactam antibiotics is limited. These data demonstrate the relationship between the chemistry of protein-reactive drugs such as penicilloyls, and how their predisposition to generating B cell responses can inform the functional implications at the clonal level.Highlights-PenG readily forms immunogenic adducts on lysine sidechains of diverse self- and non-self proteins including complete serum under physiological conditions.-PenG-protein adductionin vitroorin vivois sufficient to elicit penicillin-specific IgG responses.-Murine B cell clonotypic responses are characterised by near-uniform antibody binding modes of similar immunogenetic origin.-The dominant murine PenG-specific clonotype is dominated by benzene ring recognition and correlates with serological cross-reactivity profiles.