Generation of Monoclonal Autoantibodies From Myelin Oligodendrocyte Glycoprotein-Specific Human B Cells Using an Optofluidic-Based Platform.

OBJECTIVES: Monoclonal antibodies (mAbs) are powerful tools for elucidating disease mechanisms. Capturing heterogeneity of patient responses-including clonality, somatic mutations, isotypes, and pathogenic potential-requires building large libraries of mAbs using high-throughput approaches. However, current techniques for identifying and isolating patient-derived mAbs targeting conformational epitopes on membrane proteins remain labor-intensive and inefficient. To address this challenge, we evaluated a cell-based optofluidic antibody discovery pipeline to generate patient-derived mAbs against myelin oligodendrocyte glycoprotein (MOG), a transmembrane autoantigen targeted in MOG antibody-associated disease (MOGAD). METHODS: An optofluidic-based workflow incorporated mammalian display of human MOG (hMOG) in a live cell-based assay (CBA) format. B-cell receptor sequences from individual hMOG-binding B cells were cloned and expressed to generate mAbs from 3 patients. The hMOG binding specificity of these mAbs was validated in off-platform hMOG-CBAs. RESULTS: hMOG-specific antibody-secreting cells in one patient represented 0.02% of all single B cells screened. From these low-frequency populations, one patient-derived IgG mAb was successfully generated and validated. This IgG mAb, characterized by a high frequency of V-region somatic mutations (5%-12.2%), bound hMOG at concentrations as low as 1 ng/mL. DISCUSSION: This workflow enables rapid discovery of rare, patient-derived mAbs targeting conformational epitopes on membrane antigens, offering a scalable approach for dissecting autoantibody repertoires.