ABSTRACT
The interaction of liposomes with the cellular arm of nonspecific (innate) immunity, i.e., with macrophages of the reticuloendothelial system (RES), has been widely recognized and intensely studied since the birth of liposome science. The humoral innate response to liposomes, manifested by activation of the complement (C) system, has also been early recognized and widely studied, but this effect got much less attention than the interaction of liposomes with phagocytes. Factors hindering progress in this area include the requirement for in vivo measurement of physiological and laboratory end points that are irrelevant from a liposome standpoint (e.g., hemodynamic analysis and C cleavage product assays), the perceived complexity
of C reactions, and unpopularity of focusing on adverse effects vis-a`-vis clinical benefits.
