The migratory properties of indium-111 oxine labelled lymphocytes in patients with chronic lymphocytic leukaemia.

These studies describe the application of a new method for following the migration of autologous lymphocytes in normal subjects and patients with chronic lymphocytic leukaemia (CLL). There is evidence that Indium 111 oxine is a reliable radioactive cell label for in vivo studies of lymphocyte traffic in man. In normal subjects, where 60-70% of the lymphocytes labelled are T cells, the results are different from those of previous workers. The lymphocytes leave the blood initially but later return to it. It is believed that this is due to the reappearance of cells which at first entered the spleen. It is suggested that the difference between these data and those of Hersey (1971) is due to the failure of lymphocytes in the latter studies to return to the blood after primary migration. In CLL no such reappearance in the blood is seen and the lymphocytes do not leave the spleen in significant numbers over 48 h. This suggests that CLL B cells either do not recirculate through spleen or that their transit time is greater than 48 h. Bone marrow localization in CLL patients is greater than in the normal subjects, suggesting that either a larger proportion of the neoplastic B lymphocytes enter this compartment or their transit time through it is longer than the transit time of a normal T cell predominant population. Localization in normal-sized lymph nodes in patients with CLL is less than that in the lymph nodes of normal subjects. This may possibly be explained by the greater propensity of T lymphocytes to enter lymph nodes than B lymphocytes, or by the altered migratory properties of CLL B lymphocytes as compared with normal B cells.