The importance of splenectomy for the adoptive immunotherapy of cancer

Adoptive immunotherapy (AIT) of cancer using lymphocytes cultured in vitro in interleukin-2 (LAK cells) has gained much attention due to the high level of broad antitumor activity both in vitro and in vivo. A major hypothesis has suggested that if unfractionated lymphoid cells grown in IL-2 can mediate significant anti-tumor effects then purified LAK effector cells should yield even higher activity. Furthermore, devising new techniques to achieve optimal expansion of the purified LAK effector cells would further improve this form of immunotherapy. In this report we present data on a new method for purifying and expanding LAK effector cells obtained from the peripheral blood and spleen. The results indicate that as a source of LAK cells, the spleen is superior both quantitatively ani qualitatively when compared to peripheral blood and should be seriously considered as the source of cells for AIT of cancer.