Antibody targeting of nanoparticles to tumor-specific receptors: immunoliposomes.

Immunoliposomes generated by coupling of antibodies to the liposomal surface allow for an active tissue targeting, e.g., through binding to tumor cell-specific receptors. Instead of whole antibodies, single-chain Fv fragments (scFv), which represent the smallest part of an antibody containing the entire antigen-binding site, find increasing usage as targeting moiety. Here we provide protocols for the preparation of type II scFv immunoliposomes by the conventional coupling method as well as the post-insertion method. Furthermore protocols to analyze binding of these immunoliposomes to antigen-expressing cells as well as internalization through receptor-mediated endocytosis are included.