Chloroquine and amphipathic peptide helices show synergistic transfection in vitro

• Published in: Gene therapy Vol. 5; no. 3; pp. 409 - 414
• Main Authors: WOLFERT, M. A, SEYMOUR, L. W
• Format: Journal Article
• Language: English
• Published: Basingstoke Nature Publishing Group 01-03-1998
• Subjects: Animals; Biological and medical sciences; Biotechnology; Chloroquine; Chloroquine - pharmacology; Cytoplasm; Deoxyribonucleic acid; DNA; Dose-Response Relationship, Drug; Drug Synergism; Fundamental and applied biological sciences. Psychology; Gene Expression; Gene therapy; Genes, Reporter; Health. Pharmaceutical industry; Hemagglutinins; Humans; Hydrogen-Ion Concentration; Industrial applications and implications. Economical aspects; Influenza; Lysine; Microinjection; Microinjections; Nuclease; Oocytes; Peptide Fragments - pharmacology; Peptides; Polylysine - genetics; Transfection; Transfection - drug effects; Xenopus; Human; Cell line; Transfection; Peptides; Chloroquine; DNA; Molecular complex; Lysine polymer; In vitro; Synergism; Vector; Genetic transfer
• ISSN: 0969-7128; 1476-5462
• DOI: 10.1038/sj.gt.3300606

A pH-responsive peptide fragment modelled on the influenza virus haemagglutinin (INF7-SGSC) can promote the transfectional activity of poly(L)-lysine (pLL)/DNA complexes against 293 cells. Chloroquine also promotes transfection, but the combination of INF7-SGSC and chloroquine gives an increased, synergistic, transfectional activity. This was unexpected since the supposed modes of action of these two agents are expected to be incompatible. Microinjection of pLL/DNA complexes into the cytoplasm of Xenopus oocytes produced greater gene expression than microinjection of free DNA, possibly reflecting nuclear-homing or protection from degradation by cytoplasmic nucleases. However, pretreatment of complexes with INF7-SGSC (but not chloroquine) before cytoplasmic microinjection promoted gene expression still further. When pLL/DNA complexes were injected directly into the nucleus, INF7-SGSC again increased gene expression. The mechanism of post-endosomal action of INF7-SGSC is unknown, but could reflect its polyanionic nature, possibly enhancing intranuclear dissociation of the complexes. Whatever the mechanism, it appears that INF7-SGSC mediates two effects-one probably endosomal and the second post-endosomal, the latter showing a synergistic transfection interaction with chloroquine.