A Protease-Dependent Mechanism for Initiating T-Dependent B Cell Responses to Large Particulate Antigens

作者：Catron Drew M; Pape Kathryn A; Fife Brian T; van Rooijen Nico; Jenkins Marc K^*

来源：The Journal of Immunology, 2010, 184(7): 3609-3617.

DOI：10.4049/jimmunol.1000077

Ab production is critical for antimicrobial immunity, and the initial step in this process is the binding of Ag to the BCR. It has been shown that small soluble proteins can directly access the lymph node follicles to reach naive B cells, but virus particles must be translocated into follicles via subcapsular sinus macrophages. In this article, we explore how large particulate Ags generate humoral immune responses. Ag-specific follicular B cells rapidly acquired Ag, presented peptide:MHC class H ligands, and produced T-dependent Ab responses following s.c. injection of 1-mu m, Ag-linked microspheres, despite the microspheres being confined to the subcapsular sinus. The mechanism of Ag acquisition did not require dendritic cells, subcapsular sinus macrophages, or B cell movement to the subcapsular sinus. Rather, B cell Ag acquisition was protease-dependent, suggesting that some protein Ags are cleaved from the surface of particles to directly initiate humoral immune responses. The Journal of Immunology, 2010,184: 3609-3617.

• 出版日期2010-4-1