Effect of macrophage activation on niosome encapsulated bleomycin in tumor bearing mice

Anticancer therapy can be made more effective by targeting the delivery of anticancer drugs to the tumor site more quantitatively. In this direction attempts have been made to activate and exploit macrophages in delivering niosomal and thermosensitive niosomal bleomycin more quantitatively to tumor site using niosome encapsulated immunomodulators muramyl dipeptide and tuftsin. Niosomal bleomycin and thermosensitive niosomal bleomycin were prepared by lipid layer hydration method. The antitumor efficacy was assessed using two tumor models viz. Sarcoma-180 and Ehrlich ascites using Balb/C mice. Tumor distribution profiles of bleomycin before and after macrophage activation were studied in tumor bearing mice. The mean survival time of Ehrlich ascites infected mice increased significantly after macrophage activation. Accumulation of higher bleomycin levels after macrophage activation exerted increased antitumor effect. The present study suggested that a more quantitative delivery of bleomycin encapsulated in niosomes, to the tumor site is possible after macrophage activation.