Rat thoracic duct lymphocytes: types that participate in inflammation.

Newly formed small lymphocytes with a short life-span in the blood are the only cells from thoracic duct lymph which accumulate in acutely inflamed tissue. This conclusion is drawn from studies in which rats with induced peritonieal exudates were injected intravenously with radioactively labeled thoracic duct cells. Radioactivity, originally vested in newly formed donor small lymphocytes, was found later in a small number of similar exudate cells. Small lymphocytes generated 10 days or more before the thoracic ducts were cannulated failed to localize in peritoneal exudates, although the cells moved in large numbers from the blood in to lymph nodes.