Related Experiment Video
Updated: May 20, 2026
Generation of Cationic Nanoliposomes for the Efficient Delivery of In Vitro Transcribed Messenger RNA
Published on: February 1, 2019
Cationic liposome-nucleic acid complexes: liquid crystal phases with applications in gene therapy
C R Safinya1, K K Ewert, Cecília Leal
1Materials Department, Physics Department, and Molecular, Cellular, & Developmental Biology Department, University of California, Santa Barbara, CA 93106, USA.
Abstract:
Cationic liposome (CL) carriers of nucleic acids are primarily studied because of their applications in gene delivery and gene silencing with CL-DNA and CL-siRNA (short-interfering RNA) complexes, respectively, and their implications to ongoing clinical gene therapy trials worldwide. A series of synchrotron-based small-angle-x-ray scattering studies, dating back to 1997, has revealed that CL-nucleic acid complexes spontaneously assemble into distinct novel liquid crystalline phases of matter. Significantly, transfection efficiency (TE; a measure of expression of an exogenous gene that is transferred into the cell by the lipid carrier) has been found to be dependent on the liquid crystalline structure of complexes, with lamellar complexes showing strong dependence on membrane charge density (σ(M)) and non-lamellar complexes exhibiting TE behavior independent ofσ(M). The review describes our current understanding of the structures of different liquid crystalline CL-nucleic acid complexes including the recently described gyroid cubic phase of CL-siRNA complexes used in gene silencing. It further makes apparent that the long-term goal of developing optimized liquid crystalline CL-nucleic acid complexes for successful medical applications requires a comprehensive understanding of the nature of the interactions of distinctly structured complexes with cell membranes and events leading to release of active nucleic acids within the cell cytoplasm.
Insights
Cationic liposomes complex with nucleic acids form unique liquid crystalline structures. These structures influence gene therapy efficiency, impacting how well genes are delivered and expressed in cells.
Area of Science:
- Biophysics
- Materials Science
- Nanotechnology
Background:
- Cationic liposomes (CL) are key carriers for nucleic acids in gene therapy.
- CL-DNA and CL-siRNA complexes are crucial for gene delivery and silencing.
- Understanding CL-nucleic acid complex structures is vital for clinical gene therapy.
Purpose of the Study:
- To review the structural characteristics of liquid crystalline cationic liposome-nucleic acid complexes.
- To correlate complex structure with transfection efficiency (TE).
- To highlight the importance of structure-cell membrane interactions for therapeutic applications.
Main Methods:
- Synchrotron-based small-angle X-ray scattering (SAXS) studies dating back to 1997.
- Analysis of liquid crystalline phases formed by CL-DNA and CL-siRNA complexes.
- Investigation of structure-dependent transfection efficiency.
Main Results:
- CL-nucleic acid complexes self-assemble into distinct liquid crystalline phases.
- Transfection efficiency depends on the liquid crystalline structure.
- Lamellar complexes show dependence on membrane charge density (σ(M)), while non-lamellar complexes are independent.
- Recently identified gyroid cubic phase in CL-siRNA complexes.
Conclusions:
- Liquid crystalline structure dictates the transfection efficiency of CL-nucleic acid complexes.
- Optimizing CL-nucleic acid complexes requires understanding their interactions with cell membranes.
- Further research into structure-dependent cellular uptake and nucleic acid release is needed for successful medical applications.
