Nonviral Vectors for Gene Therapy (eBook)

Lipid- and Polymer-based Gene Transfer

Leaf Huang, Dexi Liu, Ernst Wagner (Herausgeber)

eBook Download: PDF | EPUB

2014 | 1. Auflage
428 Seiten
Elsevier Science (Verlag)
978-0-12-800367-1 (ISBN)

The field of genetics is rapidly evolving, and new medical breakthroughs are occurring as a result of advances in our knowledge of genetics. Advances in Genetics continually publishes important reviews of the broadest interest to geneticists and their colleagues in affiliated disciplines.

Includes methods for testing with ethical, legal, and social implications
Critically analyzes future directions
Written and edited by recognized leaders in the field

The field of genetics is rapidly evolving, and new medical breakthroughs are occurring as a result of advances in our knowledge of genetics. Advances in Genetics continually publishes important reviews of the broadest interest to geneticists and their colleagues in affiliated disciplines. Includes methods for testing with ethical, legal, and social implications Critically analyzes future directions Written and edited by recognized leaders in the field

Front Cover 1
Advances in
4
Copyright 5
DEDICATION 6
CONTENTS 8
CONTRIBUTORS 12
Chapter 1 - Nonviral Vectors: We Have Come a Long Way 16
1. INTRODUCTION 17
2. CHEMICAL METHODS 17
3. PHYSICAL METHODS 23
4. PERSPECTIVES 26
ACKNOWLEDGMENTS 26
REFERENCES 26
Chapter 2 - Lipid Nanoparticles for Gene Delivery 28
1. INTRODUCTION 29
2. RATIONAL DESIGNS TO OVERCOME EXTRACELLULAR AND INTRACELLULAR BARRIERS 30
3. CURRENT LIPIDIC VECTORS FOR GENE DELIVERY 33
4. GENE THERAPY APPLICATIONS 39
5. PHARMACOKINETICS, BIODISTRIBUTION AND TOXICITY OF LNPS 41
6. CLINICAL TRIALS 43
7. CONCLUSIONS 45
ACKNOWLEDGMENTS 45
REFERENCES 45
Chapter 3 - Nanotechnology for In vivo Targeted siRNA Delivery 52
1. RNA POTENTLY MODIFIES GENE EXPRESSION 53
2. TARGETING STRATEGIES 55
3. TARGETING THE LIVER 61
4. TARGETING PRIMARY TUMORS AND METASTASIS 71
5. ENDOTHELIAL CELL TARGETING 75
6. FUTURE PERSPECTIVES 77
REFERENCES 79
Chapter 4 - Lipid Nanoparticles for Short Interfering RNA Delivery 86
1. INTRODUCTION 87
2. CHALLENGES AND STRATEGIES FOR DELIVERY OF SIRNA 88
3. LIPID-BASED DELIVERY SYSTEMS 93
4. LNP-SIRNA FORMULATIONS IN CLINICAL TRIALS 110
5. FUTURE PROSPECTS 112
REFERENCES 117
Chapter 5 - Composite Nanoparticles for Gene Delivery 126
1. NANOMEDICINE AND GENE THERAPY 127
2. COMPOSITE NANOPARTICLES 128
3. FABRICATION METHODS OF COMPOSITE NANOPARTICLES 128
4. COMPOSITE NANOPARTICLES FOR TARGETED GENE DELIVERY 134
5. CONCLUSION 146
ACKNOWLEDGMENTS 146
REFERENCES 146
Chapter 6 - Multifunctional Enveloped Nanodevices (MENDs) 154
1. INTRODUCTION 155
2. R8-MEND 157
3. KALA-MEND 169
4. MITO-PORTER 174
5. YSK-MEND 187
6. SS-CLEAVABLE PROTON-ACTIVATED LIPID-LIKE MATERIAL (SSPALM) 199
7. PERSPECTIVES 206
ACKNOWLEDGMENTS 207
REFERENCES 207
Chapter 7 - Lipid-Coated Calcium Phosphate Nanoparticles for Nonviral Gene Therapy 220
1. RECENT PROGRESS OF NONVIRAL GENE THERAPY AND IN VITRO/IN VIVO DELIVERY SYSTEMS 221
2. LCP NANOPARTICLES AS A MULTIFUNCTIONAL PLATFORM FOR GENE DELIVERY 225
3. POTENTIAL THERAPEUTIC APPLICATIONS OF LCP: CANCER, CHRONIC LIVER DISEASE, AND GENE THERAPY 234
4. LCP NANOPARTICLES: CONCLUSIONS 238
REFERENCES 238
Chapter 8 - Polymers for Nucleic Acid Transfer—An Overview 246
1. FIVE DECADES IN POLYPLEXES: CHALLENGES AND BREAKTHROUGHS 247
2. OPTIMIZING THE CORE: BIODEGRADABLE AND BIOCOMPATIBLE POLYMERS 250
3. OPTIMIZING THE SHELL: BIOINSPIRED SMART POLYPLEXES 256
4. NEXT STEPS: MULTIFUNCTIONAL AND SEQUENCE-DEFINED POLYMERS 260
5. PERSPECTIVES 264
REFERENCES 264
Chapter 9 - Recent Developments in Nucleic Acid Delivery with Polyethylenimines 278
1. INTRODUCTION 279
2. MECHANISM OF PEI-MEDIATED DNA TRANSFECTION 280
3. PROTON SPONGE: MYTH OR REALITY? 283
4. PEI FOR GENE DELIVERY 288
5. PEI DERIVATIVES FOR THE DELIVERY OF EXON SKIPPING OLIGONUCLEOTIDES 292
6. PEIS FOR SIRNA DELIVERY 293
7. CONCLUSION 297
REFERENCES 297
Chapter 10 - Bioresponsive Polymer-Based Nucleic Acid Carriers 304
1. INTRODUCTION 305
2. POLYMER SELF-ASSEMBLIES FOR NUCLEIC ACID DELIVERY 307
3. REDUCTIVE ENVIRONMENT-RESPONSIVE NUCLEIC ACID DELIVERY 311
4. ACIDIC PH-RESPONSIVE NUCLEIC ACID DELIVERY 317
5. OTHER STIMULI-RESPONSIVE NUCLEIC ACID DELIVERY 325
6. CONCLUSION AND FUTURE PERSPECTIVES 329
REFERENCES 329
Chapter 11 - Chitosan-Based Nanoparticles for Mucosal Delivery of RNAi Therapeutics 340
1. INTRODUCTION 341
2. RNA INTERFERENCE 342
3. THE MUCOSAL BARRIER 345
4. MUCOADHESIVE BIOMATERIALS 348
5. CHITOSAN 350
6. CHITOSAN/SIRNA NANOPARTICLES 351
7. CHITOSAN/SIRNA NANOPARTICLES FOR DELIVERY ACROSS MUCOSAL BARRIERS 355
8. CONSIDERATIONS AND FUTURE PERSPECTIVES 357
REFERENCES 360
Chapter 12 - Polycation-Mediated Integrated Cell Death Processes 368
1. INTRODUCTION: CELL DEATH DEFINITIONS, GUIDELINES, AND PROCESSES 369
2. LYSOSOMAL-RELATED CELL DEATH 382
3. ER-RELATED CELL DEATH 388
4. MITOCHONDRION-RELATED CELL DEATH ON POLYCATION TREATMENT 391
5. CELL DEATH-ASSAY DESIGN, CONSIDERATIONS, AND INTERPRETATIONS 395
6. SAFER DESIGN OF POLYCATIONIC SYSTEMS 399
7. CONCLUSIONS 402
REFERENCES 402
INDEX 414
COLOR PLATES 424

Chapter One

Nonviral Vectors

We Have Come a Long Way

Tyler Goodwin and Leaf Huang1 Division of Molecular Pharmaceutics and Center for Nanotechnology in Drug Delivery, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
1 Corresponding author: E-mail: leafh@email.unc.edu

Abstract

Gene therapy, once thought to be the future of medicine, has reached the beginning stages of exponential growth. Many types of diseases are now being studied and treated in clinical trials through various gene delivery vectors. It appears that the future is here, and gene therapy is just beginning to revolutionize the way patients are treated. However, as promising as these ongoing treatments and clinical trials are, there are many more barriers and challenges that need to be addressed and understood in order to continue this positive growth. Our knowledge of these challenging factors such as gene uptake and expression should be expanded in order to improve existing delivery systems. This chapter will provide a brief overview on recent advances in the field of nonviral vectors for gene therapy as well as point out some novel vectors that have assisted in the extraordinary growth of nonviral gene therapy as we know it today.

Keywords

Cationic lipids; Cationic polymers; Electroporation; Genetic material; Hydrodynamic injection

1. Introduction

The past several decades have shown immense growth in the knowledge of the ability to create and improve nonviral vectors for the delivery of genetic material. This genetic material has great promise as a therapeutic agent against numerous aliments including genetic disorders, chronic and acute diseases, and cancer. Within this field of nonviral vectors, we have produced promising physical methods and chemical vectors for gene delivery consisting of electroporation techniques, cationic lipids, cationic polymers, hybrid lipid polymers, as well as many others. An increased understanding of the field has catalyzed efficiency to new levels in which delivery of plasmid DNA or oligonucleotide into cells can be well characterized and has yielded promising results in preclinical and clinical trials. These vectors have shown to be a promising alternative to viral vectors due to their safety, adaptability, and efficiency in large-scale production. Nonviral vectors have demonstrated their potential to be the next delivery systems of genetic material. They have been shown to exhibit cell specificity through addition of targeting ligands, minimal immune toxicities through addition of inflammatory suppressor molecules, as well as sufficient genetic material release into the cytoplasm of the cell through endosomal destabilization via proton sponge effect or other mechanisms. However, even with these strides, the field of nonviral gene therapy has many areas that need to be addressed, particularly in gene release, nuclear uptake, and expression, which are lagging behind viral vector capabilities. With each vector comes advantages and disadvantages, which will be addressed throughout Part I and Part II of this book.

2. Chemical Methods

The chemical methods which deliver genetic material via a vector consisting of cationic lipids (lipoplex), cationic polymers (polyplex), or lipid-polymer hybrids (lipopolyplex) have shown promise. These vectors are being used as a systemic approach to delivering genetic material. Therefore, many challenges need to be addressed in order to improve and generate ideal nonviral vectors. These vectors must overcome barriers which consist of extracellular stability, specific cell targeting, internalization, endosomal escape, nucleotide release, nuclear envelope entry, and genome integration (Figure 1.1) (Hu, Haynes, Wang, Liu, & Huang, 2013). These first few barriers mentioned seem to have been accomplished to a reasonable level. Multiple vectors have become efficient at achieving long circulation half-life with stable carrier molecules and the addition of hydrophilic moieties such as polyethylene glycol (PEG). The improved cell specificity and internalization with the conjugation of targeting ligands, as well as endosomal escape through the proton sponge effect, have also been achieved with moderate success. By overcoming these initial barriers and being able to deliver genetic material into the cytoplasm of the diseased cell, numerous oligonucleotides, mainly siRNA, are reaching new levels in clinical trials. However, in order to truly reach clinical efficiency in DNA delivery, we must improve intracellular nucleotide release, nuclear entry, and genome integration.

Figure 1.1 Proposed mechanism for intracellular delivery of DNA by lipid calcium phosphate (LCP).

Stepwise scheme for nonviral acid-sensitive vector (LCP), in which (a) the vector is internalized through receptor-mediated endocytosis, (b) PEG is shed from the vector, (c,d) vector and endosome further destabilized as endosome’s pH decreases and releases the DNA–peptide complex into the cytoplasm. The DNA–peptide complex enters the nucleus through the nuclear pore, where it dissociates and releases free DNA, which is transcribed to mRNA, migrates to the cytoplasm to be translated, and results in desired protein synthesis (Hu et al., 2013). Original figure was prepared by Bethany DiPrete. (See the color plate.)

2.1. Cationic Lipid-Based Nanoparticles (Lipoplex)

Cationic lipid-based gene delivery (lipofection) was first published by Felgner’s group in the late 1980s (Felgner et al., 1987). It has become the most studied and popular of all nonviral gene delivery methods and is discussed further in part I, chapters 2, 3, 4, and 7. The basis for using cationic lipids as a delivery system for negatively charged DNA is that the positively charged hydrophilic head group can condense with the DNA while the hydrophobic tail can form micellar or bilayer structures around the DNA. This complexation of lipids around the DNA has been termed a lipoplex and yields DNA protection against nucleases. There are numerous lipid structures that have been tested in order to find optimal lipids to form a lipoplex structure with DNA. The head groups can vary from primary, secondary, and tertiary amines, or quaternary ammonium salts as well as phosphorus, guanidino, arsenic, imidazole, and pyridinium groups. The hydrophobic tails consist of aliphatic chains which can be unsaturated or saturated and are connected to the hydrophilic head by a linker usually consisting of an ester, ether, carbamate, or amide. Cholesterol, as well as other steroids, is usually included in the formulation of these lipoplexes in order to increase the stability and flexibility of these vectors and have been shown to improve transfection in vivo. All of these components are critical in formulating promising nonviral gene delivery vectors. Varying these components can drastically change the transfection efficiency as well as improve uptake into the cell and release from the endosome. The electrostatic interaction between the negatively charged cellular membrane and the positively charged lipid head groups is vital in achieving higher levels of cellular uptake. The lipid fusion mechanism in which the positively charged vectors fuse with the cellular membrane ultimately resulting in cellular uptake of genetic material is promoted by vectors with increased flexibility as well as neutral or helper lipids (colipids) that can assist in this fusion with the cellular membrane (Li & Szoka, 2007). The fusogenic properties which facilitate cellular uptake are also valuable in the endosomal escape of lipoplexes through membrane destabilization followed by DNA release from the vector into the cytoplasm of the cell. Although the simple early lipoplexes have the capability to deliver genetic material to cells, they have drawbacks which include low transfection, an inability to target specific cells, short half-life, and toxicity due to the positively charged lipids used. Many more details and examples of cationic lipid vectors are discussed in part I, chapters 2, 3, 4, and 7.

To address the short circulation and toxicity issues with cationic lipid vectors, PEG has been introduced to the surface of these vectors in order to shield the positive charge and reduce opsonization from the reticuloendothelial system. The addition of PEG increased circulation time, allowing more time for these vectors to transfect cells (Harvie, Wong, & Bally, 2000); however, the surface PEG prevents an interaction between the cationic lipoplexes and anionic cell membrane, reducing the overall transfection efficiency. Therefore, in order to increase cellular uptake of these PEGylated lipoplexes, several strategies have been devised. The conjugation of cell-specific targeting ligands to the distal end of PEG, as well as the addition of PEG-lipid conjugates with shorter alkylated chains that can shed off the vector while in circulation over time, have shown promise. The incorporation of chemically sensitive bonds has also improved the shedding of PEG once inside an acidic or reducing environment such as the endosome or cytoplasm (Li & Szoka, 2007).

Prolonged circulation time and decreased toxicity due to surface modification makes targeted gene delivery to cells located in the interstitial regions possible. Improvements in these nonviral cationic lipid vectors have proved to be promising in gene transfer, especially in the field of siRNA delivery. In addition to its...

Erscheint lt. Verlag	19.11.2014
Sprache	englisch
Themenwelt	Studium ► 2. Studienabschnitt (Klinik) ► Humangenetik
	Naturwissenschaften ► Biologie ► Genetik / Molekularbiologie
	Naturwissenschaften ► Biologie ► Zellbiologie
	Technik
ISBN-10	0-12-800367-7 / 0128003677
ISBN-13	978-0-12-800367-1 / 9780128003671

Haben Sie eine Frage zum Produkt?

PDF (Adobe DRM)
Größe: 29,9 MB

Kopierschutz: Adobe-DRM
Adobe-DRM ist ein Kopierschutz, der das eBook vor Mißbrauch schützen soll. Dabei wird das eBook bereits beim Download auf Ihre persönliche Adobe-ID autorisiert. Lesen können Sie das eBook dann nur auf den Geräten, welche ebenfalls auf Ihre Adobe-ID registriert sind.
Details zum Adobe-DRM

Dateiformat: PDF (Portable Document Format)
Mit einem festen Seitenlayout eignet sich die PDF besonders für Fachbücher mit Spalten, Tabellen und Abbildungen. Eine PDF kann auf fast allen Geräten angezeigt werden, ist aber für kleine Displays (Smartphone, eReader) nur eingeschränkt geeignet.

Systemvoraussetzungen:
PC/Mac: Mit einem PC oder Mac können Sie dieses eBook lesen. Sie benötigen eine Adobe-ID und die Software Adobe Digital Editions (kostenlos). Von der Benutzung der OverDrive Media Console raten wir Ihnen ab. Erfahrungsgemäß treten hier gehäuft Probleme mit dem Adobe DRM auf.
eReader: Dieses eBook kann mit (fast) allen eBook-Readern gelesen werden. Mit dem amazon-Kindle ist es aber nicht kompatibel.
Smartphone/Tablet: Egal ob Apple oder Android, dieses eBook können Sie lesen. Sie benötigen eine Adobe-ID sowie eine kostenlose App.
Geräteliste und zusätzliche Hinweise

Buying eBooks from abroad
For tax law reasons we can sell eBooks just within Germany and Switzerland. Regrettably we cannot fulfill eBook-orders from other countries.

EPUB (Adobe DRM)
Größe: 12,0 MB

Dateiformat: EPUB (Electronic Publication)
EPUB ist ein offener Standard für eBooks und eignet sich besonders zur Darstellung von Belletristik und Sachbüchern. Der Fließtext wird dynamisch an die Display- und Schriftgröße angepasst. Auch für mobile Lesegeräte ist EPUB daher gut geeignet.

Buying eBooks from abroad
For tax law reasons we can sell eBooks just within Germany and Switzerland. Regrettably we cannot fulfill eBook-orders from other countries.

Print-Ausgabe

Buch | Hardcover

147,15 €