Fate of autogenous canine lymphocytes after injection into an afferent lymphatic of the popliteal lymph node.

Dog thoracic duct lymphocytes were labeled in vitro with (3)H-uridine and infused into an afferent lymphatic of the popliteal lymph node of the same dog. Ten minutes after infusion nearly all the injected radioactivity was recovered from the lymph node. An effect of infusion flow rate on the percentage of cells retained by the lymph node was observed (1/2) to 3(1/2) hours after infusion, and was probably mediated by the tendency of the node to become edematous after infusions at a rate exceeding 0.045 ml/min. Edematous nodes retained 83.7% of the cells, as compared to 47.5% for nonedematous nodes. As early as 30 minutes after infusion a small amount of (3)H-radioactivity was found in the spleen and thoracic duct lymph. The deep iliac and paraaortic nodes on the side of the infusion contained significant amounts of (3)H-radioactivity, while negligible amounts were detected in the contralateral popliteal node at any time. The intranodal localization of the (3)H-labeled cells was studied by radioautography. All labeled cells remained intrasinusoidal during the first 4 hours after infusion. At 9 and 21 hours some labeled cells were located in the extrasinusoidal parenchymal lymphoid tissue of the cortex and the medulla, but the majority still remained intrasinusoidal.