450 Developing Methods for High-Resolution Characterization of Plasma Cells

Abstract

OBJECTIVES/GOALS: Antibodies play an important role in the pathogenesis of a wide range of diseases, including cancer, autoimmune diseases, and infections. There are currently no reliable methods to isolate and study specific plasma cell subpopulations as antibody production sources. We aim to develop methods to study plasma cells in high resolution. METHODS/STUDY POPULATION: We will use molecular cloning to engineer fusion proteins that would bind plasma cell proteins to study these cells based on their surface features. The first phase of our study consists of assessing the efficacy of this plasma cell isolation method in established cell lines (e.g., RPMI 8226) and also antibody-secreting cell lines that we are establishing as a part of this study. In the second phase of the study, we will assess the efficacy of this method by studying antigen-specific plasma cell populations in the bone marrow aspiration samples of 20 healthy volunteers using various assays, including ELISPOT, flow cytometry, and fluorescent microscopy. RESULTS/ANTICIPATED RESULTS: We have designed the constructs and have completed the cloning. The final plasmids have been verified using various restriction enzymes and Sanger sequencing. Following the transfection of Freestyle HEK 293F cells and isolation of respective proteins, we expect to be able to utilize these engineered proteins to differentiate various antibody-secreting plasma cells. We will use cell lines for proof-of-concept experiments and will subsequently move this method to human bone marrow samples. We expect to be able to visualize multiple specific antibody-secreting plasma cell populations using fluorescent microscopy and utilize this method to isolate them by cell sorting via flow cytometry. DISCUSSION/SIGNIFICANCE: We expect to be able to use this method to target specific plasma cell clones in the advancement of precision medicine regarding the treatment of plasma cell disorders (e.g., multiple myeloma) and also expand its use in other areas, such as antibody discovery and the assessment of the humoral immune responses in infectious diseases.