HEVs, lymphatics and homeostatic immune cell trafficking in lymph nodes

Abstract

In search of foreign antigens, lymphocytes recirculate from the blood, through lymph nodes, into lymphatics and back to the blood. Dendritic cells also migrate to lymph nodes for optimal interaction with lymphocytes. This continuous trafficking of immune cells into and out of lymph nodes is essential for immune surveillance of foreign invaders. In this article, we review our current understanding of the functions of high endothelial venules (HEVs), stroma and lymphatics in the entry, positioning and exit of immune cells in lymph nodes during homeostasis, and we highlight the unexpected role of dendritic cells in the control of lymphocyte homing through HEVs.

Fibroblastic reticular cells of the lymph node are required for retention of resting but not activated CD8 + T cells

“…FRCs have been considered to contribute to LN function by promoting the accumulation of naïve T cells and facilitating contacts between T cells and antigen-bearing DCs (1,30). However, the role of FRCs with respect to the functions and trafficking of activated T cells has not been assessed in vivo because it has not been possible to alter experimentally these cells or their products after the onset of an infection.…”

Follicular dendritic cell disruption as a novel mechanism of virus-induced immunosuppression

“…3A). Between 4 and 48 hpi, most of the BTV-infected cells were confined inside the LN sinuses, which are delimited by a basal membrane identified with a specific staining for perlecan (13) (Fig. 3B and Table S1).…”

Immunomodulatory Roles of Lymphatic Vessels in Cancer Progression

“…Vascular and microcirculatory physiologists have traditionally focused on the fluid and solute transport functions of the lymphatic system and its relation to blood capillaries and the interstitial space (13), as well as the regulation of pump function by the collecting lymphatic vessels (14). Tumor biologists have pieced together the molecular regulators of lymphangiogenesis by tumor cells and inflammatory leukocytes in the tumor microenvironment (1, 2), whereas immunologists have traditionally considered mostly the anatomic aspects of the lymphatic system, whereby lymphatic vessels serve to transport leukocytes and antigens to the lymph node, where cell-cell interactions regulate adaptive immune responses (15,16). Only within the last few years has each of these growing research areas begun to overlap at their boundaries, and at these interfaces entirely new functions of lymphatic vessels have begun to emerge, as the complex, multifaceted roles are now coming to light.…”