Dendritic cells in lymph nodes

Reddy ST, Rehor A, Schmoekel HG (2006) In vivo targeting of dendritic cells in lymph nodes with polypropylene sulfide) nanoparticles. J Control Release 112 26-34... 

A natural mutation in mice, the pit mutation, has helped to elucidate the role of CCR7 and its ligands. Mice homozygous for the mutation show impaired homing of T-cells to the lymph nodes and spleen (241). These mice also show a decreased number of interdigitating dendritic cells in lymph nodes. Recently, the pit mutation has been associated with a deletion that results in the lack of MIP-3 and reduced expression of SLC (242). The phenotype of pit mice reflects the role of CCR7 in dendritic and T-cell recruitment. 

Mempel TR, Henrickson SE, von Andrian UH (2004) T-cell priming by dendritic cells in lymph nodes occurs in three distinct phases. Nature 427 154-159... 

The relevance of the A3 receptor over the other adenosine subtypes in immature human dendritic cells is attested to by different studies demonstrating a role for this receptor in the increase of intracellular calcium, actin polymerization and chemot-axis (Panther et al. 2001 Fossetta et al. 2003) (Fig. 12.5). However a loss of the A3 and an increase of the A2A receptor has been reported during maturation of dendritic cells. This switch has been interpreted as a protective effect of adenosine in the context of tissue injury as A2A activation plays an inhibitory role on dendritic cells migration. In this way adenosine could counterbalance inflammatory stimuli by delaying the arrival of mature dendritic cells to lymph nodes, thereby impairing the... 

Common in dendritic cells of lymph nodes mainly with CAMS.2... 

Jang MH, Sougawa N, Tanaka T, et al. CCR7 is critically important for migration of dendritic cells in intestinal lamina propria to mesenteric lymph nodes. J Immunol 2006 176(2) 803-810. 

El-Ghorr, A. A. and Norval, M., A monoclonal antibody to cis-urocanic acid prevents the UV-induced changes in Langerhans cells and DTH responses in mice, although not preventing dendritic cell accumulation in lymph nodes draining the site of irradiation and contact hypersensitivity responses, J. Invest. Dermatol. 105, 264-268, 1995. 

A readily distinguished subtype, organized into the primary follicles of B-ceU zones focused around follicular dendritic cells in the white pulp of the spleen and the cortical areas of peripheral lymph nodes. 

Sertl, K., Takemura, T., Tschachler, E., Ferrans, V.J., Kaliner, M.A. and Shevach, E.M. (1987). Dendritic cells in cutaneous, lymph node and pulmonary lesions of sarcoidosis. Scand. J. Immunol. 25, 461-467. 

When performing cytokeratin immunostaining of SLNs, one should use a cocktail such as AE1/AE3 CAM5.2 is less desirable because of the manner in which it stains dendritic cells in the lymph node. Micrometastatic cells occur in small clusters less than 2 mm in diameter within the lymph node or subcapsular sinus, and they need to be distinguished from the dendritic appearance of the interstitial reticulum cells of the lymph node, which are also keratin positive. o Studies witfi larger numbers of patients are needed to discern if the site of lymph node micrometastasis (peripheral sinus versus parenchyma of lymph node) is clinically significant. 

It has been reported to stimulate humoral and cellular immune responses in combination with several subunit antigens. It has also been proven safe, and does not cause any major adverse reactions. In clinical trials it has already been used with influenza, HSV or HIV antigens, and has been marketed as part of an enhanced influenza vaccine for the elderly. MF59 does not form a depot at the injection site, but targets macrophages and dendritic cells at the site of injection and in lymph nodes. 

Katakai, T., Hara, T., Lee, J. H., Gonda, H., Sugai, M., and Shimizu, A. (2004) A novel reticular stromal structure in lymph node cortex an immune-platform for interactions among dendritic cells, T cells and B cells. Int. Immunol. 16, 1133-1142. 

Once in the lymph node, dendritic cells may be involved in the regulation of lymphocyte traffic by secreting chemokines that can attract T lymphocytes. For example, DK-CKl is produced by dendritic cells in the T-lymphocyte-rich areas of lymph nodes and is chemotactic for naive T lymphocytes (73). IL-16 is also secreted by dendritic cells and chemotactic for T lymphocytes. Interestingly, the reverse is also true, lL-16 is secreted by T lymphocytes and chemotactic for dendritic cells suggesting a complex mechanism of crosstalk between the two cell types (74). 

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