Interdepartmental Research Unit of Peptide and Protein Chemistry and Biology, Department of NeuroFarBa, University of Florence, Sesto Fiorentino, Italy.
Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.
Clin Biochem. 2024 Dec;133-134:110838. doi: 10.1016/j.clinbiochem.2024.110838. Epub 2024 Nov 1.
Monitoring of therapeutic antibody adalimumab (ADL) and of anti-adalimumab antibodies (AAA) in autoimmune diseases patients' sera has achieved increased attention since several studies showed a correlation between AAA levels and treatment failure. We evaluated a new surface plasmon resonance (SPR)-based method that, with slight changes in the analysis condition and in the ligand immobilized on the chip surface, allows to monitor both AAA and ADL. This new label-free method does not require sample pretreatments, and it is fully automated, only requiring the preparation of the chip, which can be used for multiple analysis, and the preparation of the sample sets.
DESIGN & METHODS: Sera from ADL-treated patients (n = 47) and controls (n = 13) were included in this study. Quantitative analysis of AAA and ADL were performed separately using a new SPR-biosensor, and a commercially available ELISA kit. Agreement was defined by overall, positive, and negative agreement. Wilson Score was used to calculate confidence intervals (CI) on binomial probability and Spearman's rho and Bland-Altman test were used to assess correlations.
ELISA and SPR-based assay were able to identify circulating AAA in ADL-treated patients, with the percentage of positivity varying among the methods, with an overall agreement of 79%. AAA were detected in 18 (38 %) out of the 47 treated patients by the ELISA whereas SPR-based assay detected 10 (21 %) out of 47 samples.
Real-time label free SPR-based protocol for both AAA and ADL quantification has been set-up. Although quantitative differences were observed when compared with ELISA, the agreement among methodologies was high, particularly for ADL quantification within the therapeutic window of the drug.
监测治疗性抗体阿达木单抗（ADL）和抗阿达木单抗抗体（AAA）在自身免疫性疾病患者血清中的情况已受到越来越多的关注，因为几项研究表明 AAA 水平与治疗失败之间存在相关性。我们评估了一种新的基于表面等离子体共振（SPR）的方法，该方法通过对分析条件和芯片表面固定的配体进行轻微改变，能够同时监测 AAA 和 ADL。这种新的无标记方法不需要对样品进行预处理，而且完全自动化，只需要准备芯片，该芯片可用于多次分析，并且可以准备多个样本集。
纳入了接受 ADL 治疗的患者（n=47）和对照组（n=13）的血清。使用新的 SPR 生物传感器和商业上可获得的 ELISA 试剂盒分别进行 AAA 和 ADL 的定量分析。通过总一致性、阳性一致性和阴性一致性来定义一致性。Wilson 得分用于计算二项概率的置信区间（CI），Spearman 相关系数和 Bland-Altman 检验用于评估相关性。
ELISA 和基于 SPR 的测定法均能够识别接受 ADL 治疗的患者中循环的 AAA，不同方法的阳性率有所不同，总一致性为 79%。ELISA 检测到 47 例治疗患者中有 18 例（38%）存在 AAA，而基于 SPR 的测定法检测到 47 例样本中有 10 例（21%）存在 AAA。
已建立用于定量测定 AAA 和 ADL 的实时无标记 SPR 方案。尽管与 ELISA 相比观察到定量差异，但这些方法之间的一致性很高，特别是在药物治疗窗口内对 ADL 的定量。
