B Lymphocytes as Antigen-Presenting Cells for CD4+ T Cell Priming In Vivo

摘要: The contribution of B lymphocytes as APCs for CD4+ T cell priming remains controversial, based on findings that cells cannot provide the requisite ligating and costimulatory signals naive to be activated. In current study, we have examined Ag-specific T:B collaboration under circumstances in which take up Ag through Ig receptors vivo. This results their activation an ability effectively stimulate both vitro aim this work was establish some key molecular interactions, well kinetics, between enable place. Our approach amplify starting pools populations vivo track directly events during initial collaborations. We show induction optimal levels a protein requires involvement cells. interaction prevents down-modulation B7 molecules usually observed absence appropriate Moreover, prevention is independent CD40:CD40 ligand contact. Finally, present data suggesting once interact, there rapid (1-2-h) down-regulation antigenic complexes surface lymphocytes, possibly prevent them from engaging other vicinity therefore focus interaction.