Effect of the physicochemical properties of initially injected liposomes on the clearance of subsequently injected PEGylated liposomes in mice.

Using mice as a model, we recently reported that the long-circulating properties of polyethylene glycol (PEG) (M.W. 2000)-modified liposomes (mPEG(2000)-liposomes) disappeared when they were intravenously injected at certain intervals [referred to as the "accelerated blood clearance (ABC) phenomenon"].

Accelerated clearance of a second injection of PEGylated liposomes in mice.

We recently reported that the firstly injected PEGylated liposomes dramatically affected the rate of blood clearance of secondly injected PEGylated liposomes in rats in a time interval of injection dependent manner [J. Control. Release (2003)].