Aim: To investigate the uptake of cyclosporine A loaded colloidal drug carriers by mouse peritoneal macrophage (MPM) in vitro.
Methods: The [3H]cyclosporine A loaded colloidal particles: polylactic acid nanospheres, polylactic acid nanocapsules, and microemulsions were prepared. The [3H]cyclosporine A loaded colloidal particles were incubated with MPM for 30 min at 37 degrees C, then the cells were separated from the colloidal particles and the radioactivity was measured by a liquid scintillation counter.
Results: In comparison to the cyclosporine A solution, the binding to polylactic acid nanospheres produced a 20-fold increase in the uptake of cyclosporine A by MPM in 30 min incubation, whereas some obvious decrease in the uptake of cyclosporine A by MPM was observed in the binding of cyclosporine A with polylactic acid nanocapsules or microemulsions. The surfactant coating and plasma protein adsorption were found to have marked effects on the uptake of cyclosporine A loaded nanospheres by MPM.
Conclusion: Our present study indicated that colloidal drug carriers might affect the targeting of cyclosporine A to mononuclear phagocyte system.