Lipid Membrane-Based Antigen Presentation to B Cells Using a Fully Synthetic Ex Vivo Germinal Center Model.
Adv Nanobiomed Res
; 2(7)2022 Jul.
Article
en En
| MEDLINE
| ID: mdl-35937779
ABSTRACT
High-affinity antigen-specific B cells are generated within specialized structures, germinal centers (GCs), inside lymphoid organs. In GCs, follicular dendritic cells (FDCs) present antigens on their membrane surface to cognate B cells, inducing rapid proliferation and differentiation of the B cells toward antibody-secreting cells. The FDC's fluid membrane surface allows B cells to "pull" the antigens into clusters and internalize them, a process that frequently involves tearing off and internalizing FDC membrane fragments. To study this process ex vivo, liposomal membranes are used as the antigen-presenting FDC-like fluid lipid surface to activate B cells. In a fully synthetic in vitro GC model (sGC), which uses the microbead-based presentation of the CD40 Ligand and a cytokine cocktail to mimic T follicular helper cell signals to B cells, liposomes presenting a model antigen mimic effectively engage B cell receptors (BCRs) and induce greater BCR clustering compared to soluble antigens, resulting in rapid antigen internalization and proliferation of the B cells. B cells showed GC-like reactions and undergo efficient IgG1 class-switching. Taken together, the results suggest that fluid membrane-bound antigen induces a strong GC response and provides a novel synthetic in vitro system for studying GC biology in health and diseases, and for expanding therapeutic B cells ex vivo.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Adv Nanobiomed Res
Año:
2022
Tipo del documento:
Article
País de afiliación:
Estados Unidos