Lymphocyte kinetics during depletion by thoracic duct drainage in calves

Previous studies have demonstrated prolonged survival of renal allografts in calves following lymphocyte depletion by thoracic duct drainage after 14 days, but not after 7 days. In an analysis of factors responsible for this time difference, serum and lymph γ- globulins and lymphocytes were assayed. The γ-globulin levels and lymphocyte numbers were somewhat lower on day 14 than on day 7 postcannulation. In contrast, the size of lymph lymphocytes was increased noticeably, with the emergence of large pale lymphocytes concomitant with marked increments of both deoxyribonucleic acid and ribonucleic acid synthesis rates. These “qualitative” changes of lymphoid morphology and function may be indicators for the optimal length of thoracic duct drainage in preparation for renal allotransplantation.