Source:
INTERNATIONAL JOURNAL OF PHARMACEUTICS, Volume 107, Number 2, p.149-157 (1994)
Abstract:
Liposomal encapsulation of the cytotoxic drugs doxorubicin or
mitoxantrone was achieved with a lipid combination of 10:1:10
DPPC/DPPG/cholesterol. Both drugs were observed, by confocal
fluorescence microscopy, to be almost entirely associated with the
liposome bilayers. A method is described for loading of macrophages
intraperitoneally with liposome encapsulated doxorubicin or
mitoxantrone and the subsequent isolation of viable macrophages (83.5
+/- 6.6\%) using a separative technique based on Ficoll and Percoll.
Confocal microscopy also revealed that the intact liposomes were
internalised in macrophages and that liposomal drug was located in
phagosomes. By comparison the free drug was located, in the case of
both mitoxantrone and doxorubicin, around the periphery of the nucleus.
No intracellular leakage of mitoxantrone from the liposomes after
internalisation by the murine peritoneal macrophages was observed
whilst some leakage was apparent for doxorubicin.
