US Patent 7534819 Compositions and methods for intracellular delivery of biotinylated cargo

The invention provides compositions for intracellular delivery of biotinylated cargo. The compositions comprise a complex formed between (a) a fusion protein comprising a protein transduction domain linked to streptavidin and (b) a biotinylated cargo for intracellular delivery. In some embodiments, the protein transduction domain comprises the protein transduction domain of the Human Immunodeficiency Virus type 1 (HIV-1) TAT protein. The complex may further comprise a biotinylated endosomal releasing polymer, such as a poly(propylacrylic acid) polymer. The invention also provides methods for obtaining intracellular delivery of biotinylated cargo and methods for obtaining cytoplasmic delivery of biotinylated cargo.