ABSTRACT
Cell penetrating peptides (CPPs) offer the exciting potential of effectively delivering macromolecules to the cytoplasm of a cell that are otherwise impermeable to the plasma membrane. Although the use of these peptides has so far been well tolerated in clinical trials, it is important to remember that some of these CPPs were originally derived from pathogenic material. We therefore sought to determine if three of the most widely studied CPPs; HIV-TAT, Antennapedia and Transportan, initiated an immune response in epithelial cells. Using conditions where these peptides efficiently delivered a rhodamine tagged BSA cargo to the interior of epithelial cells, we failed to observe an effect on cell viability as determined by MTT assay (P>0.05). Further, CPP-mediated delivery of this protein cargo failed to activate NFκB, which would be indicative of toll-like receptor signalling. Finally, no significant increase in the release of the inflammatory cytokines interleukin (IL)-8 and IL-6 was detected in epithelial cells exposed to CPP complexes for 72 h (P>0.05). Together, these results indicate that these commonly used CPPs are passive carriers that do not initiate epithelial cell-associated 'danger signals' during the process of cytoplasmic delivery of a model protein cargo.
Subject(s)
Alveolar Epithelial Cells/immunology , Cell-Penetrating Peptides/adverse effects , Drug Delivery Systems/adverse effects , Enterocytes/immunology , Immunity, Innate , Keratinocytes/immunology , Alveolar Epithelial Cells/cytology , Alveolar Epithelial Cells/metabolism , Antennapedia Homeodomain Protein/adverse effects , Antennapedia Homeodomain Protein/chemistry , Biological Transport , Cell Line , Cell Survival , Cytokines/metabolism , Drosophila Proteins/adverse effects , Drosophila Proteins/chemistry , Drug Compounding , Enterocytes/cytology , Enterocytes/metabolism , Fluorescent Dyes/chemistry , Fluorescent Dyes/metabolism , Galanin/adverse effects , Galanin/chemistry , Humans , Keratinocytes/cytology , Keratinocytes/metabolism , Oligopeptides/adverse effects , Peptide Fragments/adverse effects , Recombinant Fusion Proteins/adverse effects , Recombinant Fusion Proteins/chemistry , Rhodamines/chemistry , Rhodamines/metabolism , Wasp Venoms/adverse effects , Wasp Venoms/chemistry , tat Gene Products, Human Immunodeficiency Virus/adverse effects , tat Gene Products, Human Immunodeficiency Virus/chemistryABSTRACT
Immediately after undergoing coronary bypass grafting using the left internal thoracic artery, a 59-year-old man developed left leg ischemia. Right-to-left femoral artery crossover bypass was performed and the ischemia resolved. A 72-year-old man developed left calf pain 12 days after a similar procedure; peripheral angiography revealed stenosis of the abdominal aorta and distal peripheral arteries, which did not require intervention.
