Lymph nodes

These are circular or oval-shaped formations ranging from 1 to 25 mm in diameter. They belong to the secondary (peripheral) lymphoid organs. There are three different structural parts of a lymph node: cortical – where B lymphocytes accumulate, paracortical – the area of T lymphocytes, and medullary – with many macrophages and few lymphocytes. Lymph node functions: central organ for lymphocyte recirculation; filter for foreign particles, molecules, tissue remnants (lymph can only enter the blood after passing through lymph nodes); site of active immune response: active site of antibody synthesis; site of formation of T effector lymphocyte clones; site of memory cell formation.

Source | Glossary of Most Commonly Used Biomedical Terms and Concepts | Lithuanian University of Health Sciences | Academician Professor Antanas Praškevičius, Professor Laima Ivanovienė