title: Dynamic imaging reveals promiscuous crosspresentation of blood-borne antigens to naive CD8+ T cells in the bone marrow.
abstract: The bone marrow (BM) hosts memory lymphocytes and supports secondary immune responses against blood-borne antigens, but it is unsettled whether primary responses occur there and which cells present the antigen. We used 2-photon microscopy in the BM of live mice to study these questions. Naïve CD8(+) T cells crawled rapidly at steady state but arrested immediately upon sensing antigenic peptides. Following infusion of soluble protein, various cell types were imaged ingesting the antigen, while antigen-specific T cells decelerated, clustered, upregulated CD69, and were observed dividing in situ to yield effector cells. Unlike in the spleen, T-cell responses persisted when BM-resident dendritic cells (DCs) were ablated but failed when all phagocytic cells were depleted. Potential antigen-presenting cells included monocytes and macrophages but not B cells. Collectively, our results suggest that the BM supports crosspresentation of blood-borne antigens similar to the spleen; uniquely, alongside DCs, other myeloid cells participate in crosspresentation.
authors: Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel.
authors: Idan
authors: I
authors: Milo
authors: Anita
authors: A
authors: Sapoznikov
authors: Vyacheslav
authors: V
authors: Kalchenko
authors: Orna
authors: O
authors: Tal
authors: Rita
authors: R
authors: Krauthgamer
authors: Nico
authors: N
authors: van Rooijen
authors: Diana
authors: D
authors: Dudziak
authors: Steffen
authors: S
authors: Jung
authors: Guy
authors: G
authors: Shakhar
mesh_terms: D000818:Animals; D017951:Antigen Presentation / Q000276:immunology*; D000938:Antigen-Presenting Cells / Q000276:immunology; D000941:Antigens / Q000097:blood / Q000276:immunology*; D015703:Antigens, CD / Q000378:metabolism; D000945:Antigens, Differentiation, T-Lymphocyte / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology; D001853:Bone Marrow / Q000276:immunology*; D001854:Bone Marrow Cells / Q000276:immunology / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D049109:Cell Proliferation; D045142:Cross-Priming / Q000276:immunology*; D003713:Dendritic Cells / Q000276:immunology; D007156:Immunologic Memory; D037181:Lectins, C-Type / Q000378:metabolism; D008213:Lymphocyte Activation; D008264:Macrophages / Q000276:immunology; D051379:Mice; D008822:Mice, Transgenic; D009000:Monocytes / Q000276:immunology; D000099192:CD69 Antigens
chemical_list: D000941:Antigens; D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D037181:Lectins, C-Type; D000099192:CD69 Antigens