Highly sensitive single-molecule counting technology for cytokeratin 18 detection in non-alcoholic fatty liver disease using novel antibodies.

[Display omitted] • We used a highly sensitive single-molecule detection system using novel antibodies for cytokeratin 18 detection. • The assay achieves a 1 pg/ml limit of quantification. • Our system holds promise for early diagnosis and dynamic monitoring of NAFLD. Non-alcoholic fatty liver disease (NAFLD) affects approximately 25 % of the global population, presenting a significant threat to human health and imposing a substantial economic burden on society. Cytokeratin 18 (CK18) has emerged as a promising non-invasive biomarker for early detection of NAFLD. However, current diagnostic methods face challenges in accurately identifying NAFLD in its early stages. To address this issue, our study aimed to generate new CK18 antibodies and utilize a highly sensitive single-molecule immunodetection system customized for NAFLD. We embarked on a process involving the production of novel CK18 monoclonal antibodies, which were subsequently engineered into recombinant forms. In comparison to commercial antibodies, our antibodies exhibited superior affinity. Grounded in the SMCxPRO platform, our assay underwent rigorous assessment, adhering to well-defined biomarker assay criteria. The assay demonstrated specificity to CK18 and achieved a lower limit of quantification of 1 pg/ml. Importantly, elevated serum CK18 levels were observed among NAFLD patients compared to healthy individuals. The single-molecule detection system, utilizing our novel antibodies, holds significant promise for the early-stage diagnosis, dynamic disease monitoring, and prognostic evaluation of NAFLD patients. [ABSTRACT FROM AUTHOR]