Lymphocyte subsets show marked differences in their distribution between blood and the afferent and efferent lymph of peripheral lymph nodes.

TLDR

Endothelial cells in different vascular beds express varying numbers of migration‑related ligands, making the vascular endothelium a key regulator of nonrandom lymphocyte subset migration. The study examined the distribution of lymphocyte subset surface phenotypes in blood, afferent lymph, and efferent lymph of a peripheral lymph node. Surface phenotypes of lymphocytes were determined using markers CD1, CD4, CD5, CD8, SBU‑T19, MHC class I, MHC class II, and sIg to assess their distribution across blood, afferent, and efferent lymph. Marked differences in lymphocyte subset percentages across compartments indicate that subsets exit blood with differing efficiencies, and lymph nodes extract subsets at rates distinct from subcutaneous vascular endothelium.

Abstract

The surface phenotypes (CD1, CD4, CD5, CD8, SBU-T19, MHC class I, MHC class II, and sIg) of cells in blood, lymph nodes, and lymph were determined to examine simultaneously the distribution of lymphocyte subsets circulating in blood, afferent lymph, and efferent lymph of a peripheral lymph node. Marked differences in the percentage of certain lymphocyte subsets were apparent within the compartments examined, suggesting that lymphocyte subsets leave the blood with differing efficiencies. Lymphocyte subsets also appeared to be extracted from the blood at different rates by lymph node as opposed to subcutaneous vascular endothelium. Endothelial cells in different vascular beds may express different numbers of molecules complementary to a set of migration-related cell surface molecules specific for each lymphocyte subset. Accordingly, the vascular endothelium would be the key factor in regulating nonrandom cell migration.