Integrated single-cell (phospho-)protein and RNA detection uncovers phenotypic characteristics of human antibody secreting cells

Abstract

Antibody-secreting cells (ASCs) secrete IgM, IgA, or IgG antibodies and are key components of humoral immunity; however, little is known about unique characteristics of the Ig-classes due to limited availability of material and challenges to quantify many intracellular molecular modalities at a single-cell resolution. We combined a method to in vitro differentiate peripheral B-cells into ASCs with integrated multi-omic single-cell sequencing technologies to quantify subclass-specific hallmark surface markers, transcriptional profiles and signaling transduction pathway components. Our approach detected differential expression of plasmablast and plasma cell markers, homing receptors and IL-2, IL-6, JAK/STAT and mTOR signaling activity across Ig-subclasses. Taken together, our integrated multi-omics approach allowed high-resolution phenotypic characterization of single cells in a complex sample of in vitro differentiated human ASCs. Our strategy is expected to further our understanding of human ASCs in healthy and diseased samples and provide a valuable tool to identify novel biomarkers and potential drug targets.