The conduit system transports soluble antigens from the afferent lymph to resident dendritic cells in the T cell area of the lymph node.
Resident dendritic cells (DC) within the T cell area of the lymph node take up soluble antigens that enter via the afferent lymphatics before antigen carrying DC arrive from the periphery. The reticular network within the lymph node is a conduit system forming the infrastructure for the fast delivery of soluble substances from the afferent lymph to the lumen of high endothelial venules (HEVs). Using high-resolution light microscopy and 3D reconstruction, we show here that these conduits are unique basement membrane-like structures ensheathed by fibroblastic reticular cells with occasional resident DC embedded within this cell layer. Conduit-associated DC are capable of taking up and processing soluble antigens transported within the conduits, whereas immigrated mature DC occur remote from the reticular fibers. The conduit system is, therefore, not a closed compartment that shuttles substances through the lymph node but represents the morphological equivalent to the filtering function of the lymph node.
Sixt
Michael
M
Department for Experimental Pathology, Lund University, 22185 Lund, Sweden. sixt@biochem.mpg.de
Kanazawa
Nobuo
N
Selg
Manuel
M
Samson
Thomas
T
Roos
Gunnel
G
Reinhardt
Dieter P
DP
Pabst
Reinhard
R
Lutz
Manfred B
MB
Sorokin
Lydia
L
D000818:Animals; D017951:Antigen Presentation; D001692:Biological Transport; D015415:Biomarkers; D039481:CD11b Antigen / Q000378:metabolism; D039521:CD11c Antigen / Q000378:metabolism; D002448:Cell Adhesion; D003713:Dendritic Cells / Q000378:metabolism* / Q000502:physiology; D005455:Fluorescent Antibody Technique; D007279:Injections, Subcutaneous; D007797:Laminin / Q000378:metabolism; D008198:Lymph Nodes / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018715:Microscopy, Video; D008970:Molecular Weight; D012155:Reticulin / Q000378:metabolism / Q000502:physiology; D013601:T-Lymphocytes / Q000166:cytology* / Q000502:physiology
D015415:Biomarkers; D039481:CD11b Antigen; D039521:CD11c Antigen; D007797:Laminin; D012155:Reticulin