title: Conduits mediate transport of low-molecular-weight antigen to lymph node follicles.
abstract: To track drainage of lymph-borne small and large antigens (Ags) into the peripheral lymph nodes and subsequent encounter by B cells and follicular dendritic cells, we used the approach of multiphoton intravital microscopy. We find a system of conduits that extend into the follicles and mediate delivery of small antigens to cognate B cells and follicular dendritic cells. The follicular conduits provide an efficient and rapid mechanism for delivery of small antigens and chemokines such as CXCL13 to B cells that directly contact the conduits. By contrast, large antigens were bound by subcapsular sinus macrophages and subsequently transferred to follicular B cells as previously reported. In summary, the findings identify a unique pathway for the channeling of small lymph-borne antigens and chemoattractants from the subcapsular sinus directly to the B cell follicles. This pathway could be used for enhancing delivery of vaccines or small molecules for improvement of humoral immunity.
authors.affiliation: Departments of Pediatrics and Pathology, Immune Disease Institute, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Ramon
authors.initials: R
authors.lastname: Roozendaal
authors.forename: Thorsten R
authors.initials: TR
authors.lastname: Mempel
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Pitcher
authors.forename: Santiago F
authors.initials: SF
authors.lastname: Gonzalez
authors.forename: Admar
authors.initials: A
authors.lastname: Verschoor
authors.forename: Reina E
authors.initials: RE
authors.lastname: Mebius
authors.forename: Ulrich H
authors.initials: UH
authors.lastname: von Andrian
authors.forename: Michael C
authors.initials: MC
authors.lastname: Carroll
mesh_terms: D000818:Animals; D017951:Antigen Presentation / Q000276:immunology; D000941:Antigens / Q000276:immunology* / Q000378:metabolism*; D001402:B-Lymphocytes / Q000276:immunology; D001692:Biological Transport / Q000276:immunology; D054382:Chemokine CXCL13 / Q000276:immunology; D008198:Lymph Nodes / Q000276:immunology* / Q000378:metabolism* / Q000648:ultrastructure; D051379:Mice; D008810:Mice, Inbred C57BL; D008854:Microscopy, Electron; D008970:Molecular Weight; D013601:T-Lymphocytes / Q000276:immunology; D013997:Time Factors
chemical_list: D000941:Antigens; D054382:Chemokine CXCL13