B cell antigens: A key to optimizing CAR-T cell therapy.

B-cells are vital immune cells that differentiate into plasma cells to produce antibodies targeting specific antigens. They also act as Antigen Presenting Cells, displaying processed antigens on Major Histocompatibility Complex class-II molecules to activate helper T-cells. This process triggers immune response and memory development. B-cells have surface antigens crucial for their function, which are often overexpressed in B cell cancers, making them targets for therapies like Chimeric Antigen Receptor (CAR) T-cell therapy. However, the choice of antigen is crucial. Tumor associated antigens are common but can cause off-target effects, while tumor specific antigens are more specific but less common. Furthermore, the precise epitope on the antigen recognized by the CAR-T cells significantly influences activation, which can also depend on the epitope's distance from the B-cell membrane. To facilitate the identification of extracellular regions of tumor antigens for CAR interactions, this review models tumor antigen structures embedded in the lipid bilayer, analyzing their roles and functions. Specifically, the characterization of B-cell surface antigens, encompassing their structural features and their potential as targets for CAR-T therapy are discussed. Each antigen is meticulously examined to gain insights into their specific roles within B cell biology and their potential as therapeutic targets. In conclusion, this review highlights the importance of understanding B cell antigens for the development of effective CAR-T cell therapies. The insights into antigen structures and functions presented here can guide the selection of optimal targets and the design of CAR-T cells to combat B cell malignancies effectively.