Gene Delivery by Cationic Liposome–DNA Complexes Containing Transferrin or Serum Albumin

This chapter discusses various methods and techniques used to prepare protein-associated lipoplexes and to evaluate their biological activity and mechanisms of interaction with cells. These approaches may constitute important tools for the development and application of protein-associated or peptide-associated lipoplexes, especially those designed for targeting purposes. The development of new approaches to improve the features of lipoplexes aiming at generating viable alternatives to viral vectors is crucial for gene therapy applications. To achieve such a goal, attempts have been made to confer viral attributes to lipoplexes—namely, through the association of certain proteins or peptides. These strategies are designed taking into consideration the various biological barriers faced by the complexes on their in vivo administration, which need to be overcome for gene expression to occur. Some important considerations are whether these improvements result in a system that, although exhibiting a satisfactory ability to mediate transfection, lead to such a complexity that could endanger its versatility and large-scale production or could limit extended/repeated in vivo use as a result of immunogenicity.