Migration Pattern of Splenic Lymphocytes after Local Labelling of the Pig Spleen with 3H-Cytidine

Abstract

In normal young pigs splenic lymphocytes were selectively labelled by injecting tritiated cytidine into a splenic artery. 10 h later several lymphoid and non‐lymphoid organs were investigated for spleen‐derived lymphocytes by autoradiography. The relative and absolute organ distribution of the labelled cells was determined. Labelled lymphocytes appeared rapidly in the peripheral blood reaching a mean labelling index of 4.8 %. More splenic lymphocytes were found in thymus dependent areas than in thymus independent areas of lymphoid organs. Nearly 40 % of all emigrated lymphocytes homed to lymph nodes and only about 1 % in the thymus. A surprisingly high number of splenic lymphocytes were located in the bone marrow and the lung.