Experimental immunotherapy of mice with transplanted MC-rhabdomyosarcoma resistant to doxorubicin.

Aim: To compare the sensitivity of doxorubicin (DOX) sensitive and DOX-resistant MC-rhabdomyosarcoma (MC-RMS) cells to the action of lymphokine-activated cells (LAC).

Results: In vitro investigations showed that LAC received from the fraction of adherent lymphocytes possess the highest activity against DOX-resistant tumor cells, and LAC from lymphocytes of total pool--against DOX-resistant tumor cells pretreated with DOX at a low dose. Adoptive immunotherapy of MC-RMS in vivo showed the highest efficacy in the cases of LAC intratumoral injection and the one combined with intraperitoneal administration of DOX at a low dose (increase of survival time by 14% and 25%, respectively).

Conclusion: Adoptive in vivo therapy of DOX-resistant Mh-RMS is effective if LAC or their combination with DOX at a low dose are administered.