title: Composites of malonic acid diamides and phospholipids--Impact of lipoplex stability on transfection efficiency.
abstract: The use of cationic lipids as gene delivery systems is a basic method in gene therapy. Through ongoing research, lipofection is currently the leader of non-viral vectors in clinical trials. However, in order to unleash the full potential of lipofection further intensive investigations are indispensable. In this study, various lipoplex formulations were compared regarding their ability to bind DNA. To obtain information about a possible premature release of DNA at the cell surface, heparin and chondroitin dependent lipoplex destabilization experiments were carried out. Complementary investigations in cell culture were performed to quantify DNA outside the cell. Additionally, DNase I stability was investigated. In this regard a multitude of methods, namely confocal laser scanning microscopy (CLSM), polymerase chain reaction (PCR), cell culture experiments, ethidium bromide assay, gel electrophoresis, Langmuir-isotherm experiments, infrared reflection absorption spectroscopy (IRRAS), Brewster angle microscopy (BAM), zeta-(ζ)-potential measurements, and dynamic light scattering (DLS), were applied. Although the complexation of DNA is a fundamental step, we show that the DNA release by biological agents (proteoglycans) and an unsuccessful cell attachment are major transfection limiting parameters.
authors.affiliation: Martin Luther University (MLU) Halle-Wittenberg, Institute of Pharmacy, Wolfgang-Langenbeck-Str. 4, 06120 Halle (Saale), Germany.
authors.forename: Christopher
authors.initials: C
authors.lastname: Janich
authors.affiliation: Martin Luther University (MLU) Halle-Wittenberg, Institute of Pharmacy, Wolfgang-Langenbeck-Str. 4, 06120 Halle (Saale), Germany; Philipps University Marburg, Department of Pharmaceutics and Biopharmacy, Ketzerbach 63, 35037 Marburg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Wölk
authors.affiliation: Martin Luther University (MLU) Halle-Wittenberg, Institute of Pharmacy, Wolfgang-Langenbeck-Str. 4, 06120 Halle (Saale), Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Erdmann
authors.affiliation: Martin Luther University (MLU) Halle-Wittenberg, Institute of Pharmacy, Wolfgang-Langenbeck-Str. 4, 06120 Halle (Saale), Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Groth
authors.affiliation: Max Planck Institute of Colloids and Interfaces, Science Park Potsdam-Golm, Am Mühlenberg 1, 14476 Potsdam, Germany.
authors.forename: Gerald
authors.initials: G
authors.lastname: Brezesinski
authors.affiliation: Martin Luther University (MLU) Halle-Wittenberg, Institute of Pharmacy, Wolfgang-Langenbeck-Str. 4, 06120 Halle (Saale), Germany.
authors.forename: Bodo
authors.initials: B
authors.lastname: Dobner
authors.affiliation: Martin Luther University (MLU) Halle-Wittenberg, Institute of Pharmacy, Wolfgang-Langenbeck-Str. 4, 06120 Halle (Saale), Germany. Electronic address: andreas.langner@pharmazie.uni-halle.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Langner
mesh_terms: D000818:Animals; D001665:Binding Sites; D002412:Cations; D002448:Cell Adhesion / Q000187:drug effects; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D003850:Deoxyribonuclease I / Q000378:metabolism; D003958:Diamide / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D018374:LLC-PK1 Cells; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D008314:Malonates / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D009690:Nucleic Acid Conformation; D010743:Phospholipids / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D013552:Swine; D014162:Transfection / Q000379:methods*; D002583:Uterine Cervical Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology
chemical_list: D002412:Cations; D008314:Malonates; D010743:Phospholipids; D003958:Diamide; D004247:DNA; D003850:Deoxyribonuclease I
keywords: Cationic lipids; Gene therapy; Lipofection; Lipoplexes; Phospholipids