title: Evaluation of strategies for the intracellular delivery of proteins.
abstract: OBJECTIVE
  The intracellular delivery of functionally active protein represents an important emerging strategy for laboratory investigation and therapeutic applications. Although a number of promising approaches for protein delivery have been developed, thus far there has been no attempt to compare the merits of the various deliver technologies. This issue is addressed in the current study.
  
  
  METHODS
  In this study we utilize a sensitive luciferase reporter gene assay to provide unambiguous and quantitative evaluation of several strategies for the intracellular delivery of a biologically active protein comprised of the Gal4 DNA binding domain and the VP16 transactivating domain.
  
  
  RESULTS
  Both a cationic lipid supramolecular complex and a poly meric complex were able to effectively deliver the chimeric transcription factor to cultured cells. In addition, protein chimeras containing the Tat cell penetrating peptide, but not those containing the VP22 peptide, were somewhat effective in delivery.
  
  
  CONCLUSIONS
  Both supramolecular protein-carrier complexes and protein chimeras with certain cell penetrating peptides can support intracellular delivery of proteins. In the cell culture setting the supramolecular complexes are more effective, but their large size may present problems for in vivo applications.
authors.affiliation: Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, 27599-7365, USA.
authors.forename: Dongjiu
authors.initials: D
authors.lastname: Ye
authors.forename: Dong
authors.initials: D
authors.lastname: Xu
authors.forename: Alex U
authors.initials: AU
authors.lastname: Singer
authors.forename: R L
authors.initials: RL
authors.lastname: Juliano
mesh_terms: D002460:Cell Line; D016503:Drug Delivery Systems / Q000379:methods*; D004353:Drug Evaluation, Preclinical / Q000379:methods; D006801:Humans; D007424:Intracellular Fluid / Q000187:drug effects*; D010957:Plasmids / Q000008:administration & dosage / Q000235:genetics; D011506:Proteins / Q000008:administration & dosage* / Q000235:genetics; D014162:Transfection / Q000379:methods
chemical_list: D011506:Proteins