Shangbin Kao , Xiaobin Liu , Juan Jin , Lin Zhang , Ting Shen , Jialong Wu , Yuan Qin , Xiumei Zhou , Xueqin Zhao , Liang Wang , Qiang He , Biao Huang
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引用次数: 0
Abstract
Background
Rituximab pharmacokinetics in patients with membranous nephropathy (MN) exhibit significant interindividual variability. Accurate measurement of serum rituximab concentrations is essential for effective therapeutic monitoring. This study develops a highly sensitive time-resolved fluoroimmunoassay (TRFIA) for rituximab (rituximab-TRFIA) with a wide detection range, aimed at enhancing therapeutic drug monitoring in MN treatment.
Methods
A capture -type rituximab-TRFIA was developed using streptavidin-coated microplates, biotinylated anti-rituximab idiotypic antibodies, and Eu3+-labeled mouse anti-human IgG targeting the Fc fragment of rituximab. The assay was used to measure rituximab serum concentrations in MN patients treated with rituximab.
Results
The linear range of rituximab-TRFIA is 0.50 to 2500 ng/mL, with a limit of detection (LOD) of 0.062 ng/mL. The intra-assay coefficient of variation (CV) ranges from 1.97 % to 9.50 %, while the inter-assay CV ranges from 7.44 % to 9.99 %. The recovery rate ranges from 99.14 % to 107.75 %. No cross-reactivity was observed with other monoclonal antibody drugs (mAbs). The detection range is two orders of magnitude higher, and the sensitivity is six times greater than that of the enzyme-linked immunosorbent assay (ELISA). Rituximab-TRFIA showed strong consistency within the same measurement range compared to ELISA (P < 0.0001). The serum rituximab levels in MN patients were significantly higher than those in the control group (P < 0.0001). Among patients who did not achieve remission, 60 % to 70 % had insufficient drug concentrations, and rituximab pharmacokinetics followed the expected trends.
Conclusions
The rituximab-TRFIA provides high sensitivity, a wide detection range, and reliable performance for monitoring serum rituximab concentrations in MN patients, supporting personalized treatment strategies.
期刊介绍:
The Official Journal of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC)
Clinica Chimica Acta is a high-quality journal which publishes original Research Communications in the field of clinical chemistry and laboratory medicine, defined as the diagnostic application of chemistry, biochemistry, immunochemistry, biochemical aspects of hematology, toxicology, and molecular biology to the study of human disease in body fluids and cells.
The objective of the journal is to publish novel information leading to a better understanding of biological mechanisms of human diseases, their prevention, diagnosis, and patient management. Reports of an applied clinical character are also welcome. Papers concerned with normal metabolic processes or with constituents of normal cells or body fluids, such as reports of experimental or clinical studies in animals, are only considered when they are clearly and directly relevant to human disease. Evaluation of commercial products have a low priority for publication, unless they are novel or represent a technological breakthrough. Studies dealing with effects of drugs and natural products and studies dealing with the redox status in various diseases are not within the journal''s scope. Development and evaluation of novel analytical methodologies where applicable to diagnostic clinical chemistry and laboratory medicine, including point-of-care testing, and topics on laboratory management and informatics will also be considered. Studies focused on emerging diagnostic technologies and (big) data analysis procedures including digitalization, mobile Health, and artificial Intelligence applied to Laboratory Medicine are also of interest.