CD4+lymphocytes are extracted from blood by peripheral lymph nodes at different rates from other T cell subsets and B cells

The circulation of lymphocyte subsets through prescapular lymph nodes in sheep has been quantified using a panel of monoclonal antibodies against sheep lymphocyte surface antigens. Differences in the extraction of lymphocyte subsets from blood by the lymph node were found with CD4+ lymphocytes being extracted at a faster rate (1/2) than CD8+, SBU‐T19+, major histocompatibility complex class II+ and B cells (1/4 to 1/5). In order to accommodate existing data on organ‐specific cell migration, the possibility is raised that two distinct families of lymphocyte adhesion molecules, one subset specific and one tissue specific, expressed on vascular endothelium could act jointly to regulate the migration of recirculating lymphocytes.