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- Herausgeber: John Wiley & Sons
- Kategorie: Wissenschaft und neue Technologien
- Sprache: Englisch
This book covers various aspects of antibody mediated drug delivery systems - theoretical aspects, processing, viral and non-viral vectors, and fields where these systems find and /or are being evaluated for applications as therapeutics and diagnostic treatment. Chapters discuss actual applications of techniques used for formulation and characterization. Applications areas include cancer, pulmonary, ocular diseases; brain drug delivery; and vaccine delivery. The contributing authors represent over 10 different countries, covering recent developments happening around the globe.
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Seitenzahl: 1043
Veröffentlichungsjahr: 2012
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Table of Contents
Title Page
Copyright
Contributors
Preface
Chapter 1: Antibody-Mediated Drug Delivery Systems: General Review and Applications
1.1 Historical Perspective
1.2 Antibodies
1.3 Antibody Mediation
1.4 Antibody-Mediated Drug Delivery Systems
1.5 Applications
1.6 Recent Trends
1.7 Future Trends
References
Chapter 2: Immunoliposomes for Cardiovascular Targeting
2.1 Introduction
2.2 Immunoliposome Targeting to Pathological Regions of the Vessel Wall
2.3 Liposome internalization by Endothelial Cells
2.4 Targeting of Atherosclerotic lesions for Tomographic Imaging
2.5 Antibody-mediated liposomes for diagnosis of Thrombosis
2.6 Thrombolytic therapy with immunoliposomes
2.7 Targeted Sealing of cell membrane lesions: Preservation of cell Viability
2.8 Accumulation of liposomes and immunoliposomes in the ischemic heart
2.9 Immunoliposomes as a drug and gene delivery vehicle to the infarcted heart
References
Chapter 3: Antibody-Mediated Drug Delivery Systems for Breast Cancer Therapeutics
3.1 Introduction
3.2 Breast Cancer
3.3 Drug Delivery Systems
3.4 Monoclonal Antibodies
3.5 Human Epidermal Growth Factor Receptor 2
3.6 Antibody-Mediated Drug Delivery System
3.7 Targets for the Treatment of Breast Cancer
3.8 Breast Cancer Therapies
3.9 The Future of Breast Cancer Therapeutics
3.10 Other Treatment Strategies
3.11 Nanotechnology
3.12 Conclusions
References
Chapter 4: Development of immunonconjugates for in vivo delivery: Cancer diagnosis, imaging, and therapy
4.1 Introduction
4.2 Immunoconjugates
4.3 Immunoconjugates in cancer therapy
4.4 Immunoconjugates for imaging
4.5 Immunoconjugates in diagnostic applications
4.6 Immunoconjugates' promising future and challenges
4.7 Summary
References
Chapter 5: Mathematical models of anti-TNF therapies and their correlation with Tuberculosis
5.1 Introduction
5.2 Tuberculosis, TNF, and anti-TNF drugs
5.3 Theoretical Models to Study TB Infection
5.4 Present and future work
References
Chapter 6: Targeted Nanoparticles in Radiotherapy
6.1 Introduction
6.2 Nanoparticles
6.3 Radiotherapy
6.4 Nanoparticles in Radiotherapy
6.5 Current and Future Developments with Nanotechnology in Radiotherapy
6.6 Conclusions
References
Chapter 7: Electrically-enhanced delivery of drugs and conjugates for cancer treatment
7.1 Introduction
7.2 Electroporation mechanisms to permeabilize the drugs and DNAs in cells
7.3 Electroporation-aided drug delivery for preclinical studies
7.4 EP applications for human patient studies
7.5 Future perspectives
7.6 Summary
References
Chapter 8: Characterization of Monoclonal Antibody variants and glycosylation
8.1 Characterization of monoclonal antibody heterogeneity by HPLC analysis
8.2 Analysis of Monoclonal Antibody Glycosylation
References
Chapter 9: Antibody-mediated drug delivery system for lymphatic targeting treatment
9.1 Introduction
9.2 Lymphatic disorders and their normal treatment
9.3 Antibody-mediated drug delivery systems for lymphatic targeting treatment
9.4 Conclusions and future perspectives
References
Chapter 10: Methods for Nanoparticle Conjugation to Monoclonal Antibodies
10.1 Introduction
10.2 Current Nanoparticle Systems used for Conjugation with mABs
10.3 Conjugation Methods
10.4 Conclusions
References
Chapter 11: Single-Use Systems in Animal Cell–based Bioproduction
11.1 Introduction
11.2 Component Offerings
11.3 Characteristics of Single-Use Systems and Their Applications
References
Chapter 12: Immunoliposomes for specific drug delivery
12.1 Introduction: advances in liposome formulation
12.2 Design of immunoliposomes for site-specific drug delivery
12.3 Cellular-specific targeting of immunoliposomes
12.4 Cellular-specific internalization of immunoliposomes
12.5 Immunoliposomes in diagnosis and therapy
12.6 Clinical use of immunoliposomes
12.7 Conclusions and perspectives
References
Chapter 13: Gene Therapy Targeting Kidney Diseases: Routes and Vehicles
13.1 Introduction
13.2 Rationale for successful gene targeting
13.3 Site-specific gene delivery
13.4 Nuclear import of gene material
13.5 Targeting the Glomerulus
13.6 Targeting the Tubule
13.7 Targeting the interstitium
13.8 Targeting muscle
13.9 Conclusions
References
Chapter 14: Detection of Antibodies to Poly(ethylene glycol) Polymers using Double-Antigen-Bridging Immunogenicity ELISA
14.1 Introduction
14.2 Methods
14.3 Results
14.4 Discussion
References
Chapter 15: Antibodies in Nanomedicine and MicroImaging Methods
15.1 Introduction: Antibody molecules and nanoparticles
15.2 Antibody-based Nanoparticles in Microimaging
15.3 Troponin T: Newer Magnetic Immunoassay Method
15.4 Gold Nanoparticles as an Antigen Carrier and Adjuvant
15.5 Immunochemical Biosensors, Nanomedicine, and Disease
15.6 Future Directions and Conclusions
References
Chapter 16: Methods for polymeric nanoparticle conjugation to Monoclonal Antibodies
16.1 Introduction
16.2 Conjugation of mAb and Polyethylenimine Nanoparticles
16.3 Conjugation of mAb to Poly(Lactide-CO-Glycolide) Nanoparticles
16.4 Conjugation of mAb to Poly(Lactic Acid) and its Derivatives
16.5 Conjugation of mAb to Other Polymeric Nanoparticles
16.6 Summary
References
Chapter 17: Plant-derived antibodies for academic, industrial, and therapeutic applications
17.1 Historical perspective
17.2 Plant-based production of recombinant proteins
17.3 Expression in an entire plant versus a plant organ
17.4 ER targeting and secretion of recombinant proteins
17.5 Expression in seeds
17.6 Transient expression
17.7 Glycosylation
17.8 Recent examples of plant-derived antibodies effective in mammalian systems
17.9 Conclusions
References
Chapter 18: Monoclonal antibodies as biopharmaceuticals
18.1 Historical Perspective
18.2 Introduction
18.3 Structure and types of mAbs
18.4 Mechanism of Action
18.5 FDA-approved mAb biopharmaceuticals in current use
18.6 Future of monoclonal antibodies as biopharmaceuticals
References
Chapter 19: Pulmonary targeting of nanoparticles and monoclonal antibodies
19.1 Introduction
19.2 Attributes of mAbs as Therapeutics for Pulmonary Diseases
19.3 Antibody-conjugated nanoparticles for lung targeting
19.4 Monoclonal Antibodies in the Treatment of Asthma
19.5 Monoclonal antibodies in the treatment of COPD
19.6 Challenges in Pulmonary disease
19.7 Conclusions
References
Chapter 20: Antibody-mediated arthritis and new therapeutic avenues
20.1 Autoantibodies in Rheumatoid Arthritis
20.2 Role of Cartilage Antigen-Specific Antibodies in Inducing Arthritis
20.3 arthritis mediation through Antibodies recognizing citrullinated antigens
20.4 Regulation at the effector level
20.5 Cartilage Damage Independent of Inflammatory Mediators
20.6 Pathogenicity of GPI-Specific Antibodies
20.7 Therapeutic Cleavage of Arthritogenic Antibodies
20.8 arthritis attenuation though Removal of specific Sugars on IgG
References
Chapter 21: Immunonanoparticles for nuclear imaging and radiotherapy
21.1 Radioisotopes and radiopharmaceuticals
21.2 Radiolabeled Antibodies
21.3 Radiolabeled Nanoparticles
21.4 Future perspectives and conclusions
References
Chapter 22: Monoclonal Antibodies in the Treatment of Asthma
22.1 Introduction
22.2 IgE
22.3 TNFα
22.4 IL-5
22.5 IL-9
22.6 IL-4 and IL-13
22.7 Targeting the T-cell
22.8 Conclusions
References
Index
Color Plates
For further information visit: the book web page http://www.openmodelica.org, the Modelica Association web page http://www.modelica.org, the authors research page http://www.ida.liu.se/labs/pelab/modelica, or home page http://www.ida.liu.se/~petfr/, or email the author at [email protected]. Certain material from the Modelica Tutorial and the Modelica Language Specification available at http://www.modelica.org has been reproduced in this book with permission from the Modelica Association under the Modelica License 2 Copyright © 1998–2011, Modelica Association, see the license conditions (including the disclaimer of warranty) at http://www.modelica.org/modelica-legal-documents/ModelicaLicense2.html. Licensed by Modelica Association under the Modelica License 2.
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Copyright © 2011 by the Institute of Electrical and Electronics Engineers, Inc.
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Library of Congress Cataloging-in-Publication Data:
Antibody-mediated drug delivery systems : concepts, technology, and applications / edited by Yashwant Pathak, Simon Benita.
p. cm.
ISBN 978-0-470-61281-1 (cloth)
I. Pathak, Yashwant. II. Benita, Simon, 1947-
[DNLM: 1. Antibodies–therapeutic use. 2. Drug Delivery Systems.
3. Drug Carriers. 4. Nanoparticles. QV 785]
615.37–dc23
2011037603
Contributors
Leonor Munoz Alcivar, Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, Florida
Simon Benita, The Institute for Drug Research of the School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
Nikolai Borisjuk, Biotechnology Foundation Laboratories, Thomas Jefferson University, Philadelphia, Pennsylvania
Manuela Calin, Institute of Macromolecular Chemistry “Petru Poni,” Iasi, Romania; Institute of Cellular Biology and Pathology “Nicolae Simionescu,” Bucharest, Romania
Luca Campana, Melanoma and Sarcoma Unit, Istituto Oncologico Veneto, Department of Oncological and Surgical Sciences, University of Padova, Padova, Italy
Weiyuan Chang, Department of Environmental and Occupational Health, School of Public Health, University of Louisville, Louisville, Kentucky; currently at Division of Preclinical Science, Center For Drug Evaluation, Taipei, Taiwan
Dave Chen, ANP Technologies, Inc., Newark, Delaware
Hong Ding, Department of Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, New York
Mohammad Fallahi-Sichani, Department of Chemical Engineering, College of Engineering, University of Michigan, Ann Arbor, Michigan
Oren Giladi, The Institute for Drug Research of the School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
William Hartner, The Center for Pharmaceutical Biotechnology and Nano medicine, Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts
Yoshitaka Isaka, Department of Geriatric Medicine and Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
Navdeep Kaur, Department of Pharmaceutics and Medicinal Chemistry, T.J.L School of Pharmacy and Health Sciences, University of the Pacific, Stockton, California
Denise E. Kirschner, Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan
Slavko Komarnytsky, Plants for Human Health Institute, FBNS, North Carolina State University, Kannapolis, North Carolina
Girish J. Kotwal, Kotwal Bioconsulting, LLC and InFlaMed, Inc., Louisville, Kentucky; currently at University of Medicine and Health Sciences, St. Kitts, WI
Uyen Minh Le, Department of Pharmaceutical Sciences, Sullivan University College of Pharmacy, Louisville, Kentucky
Tatyana Levchenko, The Center for Pharmaceutical Biotechnology and Nano medicine, Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts
Junling Li, University of Louisville School of Medicine, Louisville, Kentucky
Jennifer J. Linderman, Department of Chemical Engineering, College of Engineering, University of Michigan, Ann Arbor, Michigan
Yijuan Liu, ANP Technologies, Inc., Newark, Delaware
Simeone Marino, Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan
David Milunic, ANP Technologies, Inc., Newark, Delaware
Misty Muscarella, Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, Florida
Kutty Selva Nandakumar, Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
Arutselvan Natarajan, Molecular Imaging Program at Stanford, Department of Radiology, School of Medicine, Stanford University, Stanford, California
Chin K. Ng, University of Louisville School of Medicine, Louisville, Kentucky
Jing Pan, ANP Technologies, Inc., Newark, Delaware
Yashwant Pathak, Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, Florida
Chris Pohl, Thermo Fisher Scientific, Sunnyvale, California
Dujie Qin, ANP Technologies, Inc., Newark, Delaware
Hiromi Rakugi, Department of Geriatric Medicine and Nephrology, Osaka University Graduate School of Medicine, Osaka Japan
Srinivasa Rao, Thermo Fisher Scientific, Sunnyvale, California
Helen Reidler, ANP Technologies, Inc., Newark, Delaware
Jeff Rohrer, Thermo Fisher Scientific, Sunnyvale, California
Rakesh Sharma, Center of Nanomagnetics and Biotechnology, Florida State University, Tallahassee, Florida; currently at Amity Institute of Nanotechnology, Amity University, Noida, India
Karthikeyan Subramani, Department of Oral Implantology and Prosthodontics, Academic Centre for Dentistry Amsterdam, Research Institute MOVE, University of Amsterdam and VU, Amsterdam, The Netherlands
Raji Sundararajan, Electrical and Computer Engineering Technology, Purdue University, West Lafayette, Indiana
Yoshitsugu Takabatake, Department of Geriatric Medicine and Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
Vladimir P. Torchilin, The Center for Pharmaceutical Biotechnology and Nanomedicine, Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts
Hieu Tran, Department of Pharmaceutical Sciences, Sullivan University College of Pharmacy, Louisville, Kentucky
Yli Remo Vallejo, ANP Technologies, Inc., Newark, Delaware
Glenn J. Whelan, College of Pharmacy, University of South Florida, Tampa, Florida
William G. Whitford, Thermo Scientific Cell Culture and BioProcessing, Thermo Fisher Scientific, Logan, Utah
Fang Wu, Department of Pharmaceutical Sciences, The State University of New York at Buffalo, Buffalo, New York
Ray Yin, ANP Technologies, Inc., Newark, Delaware
Zhirong Zhang, Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, West China School of Pharmacy, Sichuan University, Chengdu, China
Ting Zheng, Thermo Fisher Scientific, Sunnyvale, California
Preface
In 1988 the first comprehensive book on antibody-mediated delivery systems was published. Although the field has developed rapidly and immensely since then, until now no attempt had been made to compile an inclusive and detailed review of the current status of antibody-medicated drug delivery systems. The aim of our book is to provide medical and scientific researchers and students working in this field with an up-to-date, practical, all-encompassing reference source on the concept, analytical development, antibody processing, and applications of antibody-mediated drug delivery systems. Leading scientists working in the field contributed to this effort with chapters on their specific expertise.
Since 1975, when J. F. Köhler and César Milstein developed hybridoma technology to produce monoclonal antibodies (mAbs) efficiently, a number of therapeutic agents based on monoclonal antibodies have emerged for the treatment of various diseases. For their groundbreaking work, Köhler and Milstein won the Nobel Prize in Physiology or Medicine in 1984. Monoclonal antibodies (mAbs) were developed originally from mice as a tool for studying the immune system. The early applications of mAbs included grouping blood types, identifying viruses, purifying drugs, and testing for pregnancy, cancers, heart diseases, and blood clots. mAbs began to reveal their full potential in 1986 when Medical Research Council researcher Gregory Winter pioneered a technique to humanize mouse mAbs. This made them better suited for human medical use, as they were much less likely to elicit an inappropriate immune response in patients. Gregory's techniques have been licensed to more than 50 companies worldwide. Subsequently, Humira became the first fully human mAb drug, launched in 2002 as a treatment for rheumatoid arthritis.
Briefly, the mAb time line is as follows:
1975 Method devised to isolate and reproduce mAbs
1986 Techniques pioneered to humanize mouse mAbs
1990 Test tube production of highly specific human mAbs
1997 First chimeric mAb, Rituxan (rituximab), approved by the U.S. Food and Drug Administration (FDA)
1998 First humanized mAb, Herceptin (trastuzumab), approved by FDA
2002 First fully human mAb Humira (adalimumab), approved by FDA
2003 First fully human mAb, Humira, launched in the UK
2005 Humira sales reach more than $200 million
It was quite interesting to note that despite the enormous effort concentrated in producing fully human mAbs, it appears that a significant number of immune responses are related to the use of such fully human mAbs. Apparently, there are other parameters not yet fully identified that elicit at least some of these immune responses (some can be associated with the excipients used in the design of the formulation of these mAbs). Although today it is not conceivable from a marketing point of view to develop mAbs that are not fully human, the chimeric forms of antibodies that are currently on the market, such as Rituxan, still have their place and continue to expand. For example, annual sales of Rituxan increased continuously have reaching a peak of $5.7 billion in 2009. A total of 28 antibody-based therapeutics have been approved to date by the FDA for clinical applications, and numerous others are currently undergoing development. The market value of antibody-based therapeutics has already reached $40 billion and is expected to reach $68 billion by year 2015. It should be emphasized that of the 10 top-selling drugs today, six are therapeutic antibodies.
This book covers important therapeutic and diagnostic aspects of mAbs. Indeed, Chapter 2 deals with applications of immunoliposomes for cardiovascular targeting. mAbs are well known for their ability to bind to a wide variety of cell-surface proteins, including tumor cell–specific proteins. mAbs can be produced that are directed against virtually any molecule, and unlike polyclonal antisera, they are highly specific. This unique feature of mAbs has opened an important arena of cancer treatment, including immunotherapy, radioimmunotherapy, and pre-targeted therapy (Chapter 3). All these treatment modalities have been developed either with mAbs alone or as conjugates of radionuclides, drugs, and toxins (effector moiety), to seek out and destroy tumor cells selectively. Although many obstacles still have to be overcome, immunoconjugates (Chapter 4) have become a valuable arsenal in the treatment of human diseases, including cancer imaging and therapy in specific targeted drug delivery therapy. Thus, mAb-based immunoconjugates are unique targeting agents for cancer diagnosis, imaging, and therapy. In addition, engineered mAb fragments and nontraditional antibody-like scaffolds (e.g., fibronectin, affibodies) directed toward many novel protein markers are under development and will provide novel options to improve drug delivery. Furthermore, as the authors of Chapter 5, Chapter 9, Chapter 12, and Chapter 18 clearly point out, antibody-mediated drug delivery systems offer promise as carriers of drugs with targeting to specific sites by the binding of mAbs and antigens on malignant or other target cells. Antibody-based therapies using antibody-mediated drug delivery systems target tumor cells while potentially sparing normal cells. Such targeted therapy approaches are employed to reduce the nonspecific toxicity of cytotoxic chemotherapy and to improve the efficacy of treatment. Some antibody-drug conjugates, such as SGN-35 and CMC-544, have demonstrated promising results in clinical trials for the treatment of Hodgkin and non-Hodgkin lymphomas. Most polymer and liposome antibody conjugates are in the preclinical stages, and further clinical studies need to be carried out to confirm the observations from in vitro cell culture experiments and in vivo animal tumor models. The concept of targeted drug delivery using immunoliposomes (liposomes bearing on their surface covalently coupled antibodies) is an appealing therapeutic strategy because of advantages such as the ability to target specific and restricted locations in the body, to deliver effective concentration of drugs to the diseased sites, and to reduce the drug concentrations at nontarget sites, resulting in fewer side effects.
In addition, the potential of renal gene therapy, which offers new strategies to treat kidney diseases, is reviewed in Chapter 13. Several experimental techniques have been developed and employed using nonviral and viral vectors. Gene transfer consists of carrying a therapeutic gene to the surface of target cells, introducing it into cells, and recruiting it into the nucleus. The development of a gene transfer method is developed to enhance the second step. In addition to the choice of delivery vehicle, the administration route and intrinsic pressure determine the site of transduction.
In Chapter 4, Chapter 6, Chapter 15, and Chapter 18, the diagnostic applications of mAbs are covered. Poly(ethylene glycol) (PEG) polymers attached to biotherapeutic molecules enhance the in vivo delivery and stability of these high-molecular-weight drugs. However, these polymers may, by themselves, be immunogenic and elicit antibodies that can reduce the efficacy of the drug and contribute to potential patient morbidity. A double-antigen-bridging ELISA immunogenicity assay for the detection of specific antidrug antibodies to PEG polymers of various sizes has now been developed.
The authors of Chapter 6, Chapter 10, and Chapter 15 emphasize the contribution of nanotechnology to the expansion of mAbs. With the emergence of nanotechnology, antibody-coated magnetic nanoparticles, portable magnetic immunoassays, nanoparticle-based antigen–nanometal conjugates, and several biomarker bioapplications are in the developmental stages to achieve microimaging at microscale, point-of-care detection devices, nano-drug delivery systems, and nanorobots, respectively.
Plant-derived antibodies offer a wide range of applications in biomedical research and metabolic engineering, and as clinical diagnostic or therapeutic agents, as proposed in Chapter 17. Even though numerous breakthroughs have been achieved in the use of plants as hosts for the production of recombinant proteins, manufacturing complex immunoglobulins is not a simple procedure with an assured favorable outcome. One of the major problems is the low yield of the recombinant antibodies in plants. Careful selection of the host species, codon optimization, engineering of genetic elements capable of stabilizing and enhancing levels of the recombinant transcript, development of novel harvesting and purifying strategies, and use of various cell compartments are but a few potential avenues that may help increase the yield of the final product.The increasing number of plant antibody–based products entering clinical trials and the market indicates an exponential growth of activities in this field. This technology is just beginning to mature, and considerable evolution may be expected in the next few decades.
Additional applications for mAb modifications which have made a huge impact in biopharmaceuticals are reviewed in Chapter 18. The simple concept of fusing antibody-producing B cells from the spleen with myeloma cells followed by isolating clones secreting monospecific antibodies for which Köhler and Milstein received a Nobel prize translated into a lifesaving treatment that specifically targets tumor cells or proinflammatory cytokines with minimal collateral damage. mAbs are heterodimeric protein molecules with an antigen-binding region that can target receptors on cancer cells and a conserved or constant region that can bind to complement components and recruit the destructive force of the immune system to target and eliminate tumor cells. Using recombinant DNA technology, the conserved parts of the mAbs can be humanized to prevent rapid clearance of antibody molecules. Several mAbs have made it to the top 12 biotech drugs list, and the application of mAbs has yet to be fully explored. The prohibitive cost of these mAbs has raised questions about their widespread use to prolong life, and questions have been raised as to whether the final 2% of life deserves to incur 98% of the lifelong medical expenses.
Many different strategies have been discussed for application of antibodies in the treatment of asthma using allergen-specific T cells and their cytokines, IgE levels and IgE inhibitors, and TNFα therapies. Nevertheless, the continued interest of academics, clinicians, and the pharmaceutical industry will help keep mAbs central to the efforts of the biotech industry. Each chapter of the book deals with the concepts, technology, and applications of mAb systems.
The editors would like to thank all the authors for their perceptive and excellent contributions. We believe that readers will benefit from the wealth of information provided in each chapter, as it will add to their scientific education as well as assist in the conceptual development of the topic. We also express our sincere appreciation to Jonathan T. Rose and Amanda Amanullah of John Wiley for their kind help and guidance throughout the entire project as well as to the Wiley staff members who helped in completing this endeavor and bringing the book to market. We thank Eleonor M. Dodard for help in word processing and formatting the text.
Yashwant Pathak
Simon Benita
Chapter 1
Antibody-Mediated Drug Delivery Systems: General Review and Applications
Navdeep Kaur
Department of Pharmaceutics and Medicinal Chemistry, T.J.L School of Pharmacy and Health Sciences, University of the Pacific, Stockton, California
Karthikeyan Subramani
Department of Oral Implantology and Prosthodontics, Academic Centre for Dentistry Amsterdam, Research Institute MOVE, University of Amsterdam and VU, Amsterdam, The Netherlands
Yashwant Pathak
Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, Florida
1.1 Historical Perspective
The term antibody was first used by Paul Ehrlich in year 1891 in his article “Experimental Studies on Immunity.” In 1890, Emil Von Behring and Shibasaburo Kitasato established the basis for serum therapy: that serum taken from animals treated with nonlethal doses of diphtheria and tetanus can be used for the treatment of diphtheria and tetanus. They followed this discovery with the theory of humoral immunity, which prompted Paul Ehrlich to propose side chain theory, which describes the interaction between antibodies and antigens. Later, in the 1920s and the 1930s, it was shown by Michael Heidelberger and Oswald Avery that antibodies are made of protein, and the biochemical aspect of antigen–antibody interactions was explained by John Marrack. In the following years, the structure of antibodies was characterized by a number of scientists independently [1].
In 1975, Köhler and Milstein successfully produced antibodies in vitro using “hybridoma technology.” This discovery allowed the production and use of antibodies on a large scale for diagnostic and therapeutic purposes. The first antibody, OKT3, was approved by the U.S. Food and Drug Administration (FDA) in 1986 for use in patients to prevent transplant rejections [2]. Since then, numerous technologies have been developed to decrease the immunogenicity of mouse antibodies by generating partial or fully human antibodies. A total of 28 therapeutic antibodies approved by the FDA are currently available in the U.S. market. It is the fastest-growing market, and its revenue is expected to increase to $62.7 billion in 2015, according to DatamonitorPlc, a London-based health information firm [3].
1.2 Antibodies
Antibodies (also known as immunoglobulins) are proteinacious in nature and are produced in response to an invasion of foreign substances in the body called antigens.
1.2.1 Structure of Antibodies
Antibodies are heavy ( ∼ 150 kDa), Y-shaped glycoproteins composed of four polypeptide chains: two long heavy or H chains and two short light or L chains. The end of light and heavy chains together constitutes a variable region (also known as antigen-binding site) consisting of 110 to 130 amino acids. The amino acid sequence in the variable region gives antibody its specificity for binding to a variety of antigens.
1.2.2 Types of Antibodies
There are five major types of antibodies, each having a specific role in the immune response:
1.2.3 Antibody Development
Over a period of time, numerous methods have been devised for the production of antibodies, the first being the hybridoma method proposed by Köhler and Milstein. This method involves immunization of mice with a mixture of antigens followed by fusion of their spleen cells with immortalized myeloma cells. These cells are then cloned and screened for production of the desired antibodies. Certain limitations associated with the method involve specificity issues, as the antibodies are derived from murine cells and thus resemble a rodent immune system and also because these antibodies are recognized as allogenic proteins in human patients, which leads to human antimouse antibody response.
Another method, the Epstein–Barr virus method, involves immortalization of human cells by the Epstein–Barr virus. The disadvantage of this method is its nonspecificity in terms of immortalizing antigen-specific B cells among a pool of peripheral blood lymphocytes.
To humanize murine antibodies further, chemical and molecular methods were devised, such as replacement of the Fc portion of murine antibodies by that of human antibodies to yield chimeric monoclonal antibodies. Also, immortalization of genes corresponding to specific antibodies, and grafting of DNA fragments determining the binding specificity of the antibody into the framework of human immunoglobulin genes, leads to the production of humanized antibodies.
The phage display method is an efficient method for the production of high-affinity antibodies. It involves ligation of a DNA library derived from B cells onto a surface protein gene of a bacteriophage. Further, phages expressing the required specificities are isolated, enriched, and used to infect Escherichia coli for the production of monoclonal antibody construct [8].
1.3 Antibody Mediation
Antibody-mediated immunity is also called humoral immunity or humoral immune response. Lymphocytes (white blood cells) are divided into two types: B lymphocytes or B cells (which secrete antibodies and are involved in humoral immunity) and T lymphocytes or T cells (which are involved in cell-mediated immunity). Both types of cells originate from the bone marrow; they become B or T cells depending on their point of maturation. T cells develop in the thymus gland; B cells develop in the bone marrow. Antibodies are produced in the body by B lymphocytes or B cells. B cells develop in the bone marrow and travel from bone marrow to the spleen. Once in the spleen, the B cells undergo a maturation process during which the genes responsible for generating antibody recombine several times. This process renders the cells highly specific for a single antigenic sequence. During maturation, each B cell undergoes selection mechanisms which ensure that it is not only specific for one antigen, but also that it does not recognize self-antigen. During this process, any B cells that recognize self-antigen either die or their activity is permanently suppressed. When a B cell has gone through the entire recombination process, it becomes fully mature. Once fully matured, the cell is at a stage where it will activate only when it recognizes a particular amino acid sequence during the course of a pathogenic infection. Mature B cells circulate throughout the body, via the bloodstream and lymphatic system, until they come into contact with the specific antigen that they recognize. When there is an infection, the invading pathogen produces antigen. Resting or naive B cells get activated when the antigen binds to its membrane, and this results in the production of numerous antibodies that bind specifically to that antigen. B cells can be activated in a T-cell-dependent or T-cell-independent manner.
1.4 Antibody-Mediated Drug Delivery Systems
Figure 1.1 Schematic representation of an antibody–drug conjugate.
Table 1.1 Antibody–Drug Conjugates Under Development
1.5 Applications
1.6 Recent Trends
1.7 Future Trends
Future trends in antibody-based therapeutics point at the development of novel synthetic entities resembling antibodies. Researchers at the University of Shizuoka (Japan), Stanford University, and the University of California–Irvine have developed plastic antibodies. These synthetic antibodies are made up of nanoparticles that bind to antigens like natural antibodies and perform similar actions [48]. Researchers at Arizona State University synthesized synthetic antibodies termed synbodies by linking the amino acid sequences or peptides by means of a linker. The synbodies are more stable than naturally produced antibodies and will make a good tool for diagnostics [49].
Another arena where development is expected is innovation in antibody engineering for higher therapeutic efficacy and cost-effective manufacturing processes. Identification of new targets and pathways of diseases for the development of antibody therapeutics with novel models of action. In the coming years antibody-based therapeutics is expected to emerge as a strong sector within the pharmaceutical industry, driving the market [50].
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Chapter 2
Immunoliposomes for Cardiovascular Targeting
Tatyana Levchenko, William Hartner, and Vladimir P. Torchilin
The Center for Pharmaceutical Biotechnology and Nanomedicine, Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts
2.1 Introduction
As for any other organ of interest, the targeting of pharmaceuticals to the heart has two main objectives: diagnostic imaging of cardiac pathologies and delivery of therapeutics to affected areas. The most important cardiac pathologies include coronary thrombosis and atherosclerosis, myocardial infarction, and myocarditis of various etiologies. An important problem to consider in using liposomes as drug carriers (a common problem with all microparticulate carriers) is the inability of liposomes to extravasate and to reach target sites in nonvascular tissues. However, despite their limitation as drug carriers, liposomes and immunoliposomes should remain highly effective for intravascular targeting, such as to cells and noncellular components within the circulatory system (blood components, endothelial cells, and subendothelial structures). Furthermore, targeting of extravascular sites after vascular disruption, such as in acute myocardial infarction, should provide a highly efficient method for the delivery of therapeutic drugs to the compromised myocardium.
“Convenient” target antigens were identified in the pathological areas of the cardiovascular system, such as collagen and other proteins in the subendothelial layer and cytoskeletal myosin in damaged myocardial cells. The availability of highly effective monoclonal antibodies against these antigens has made it possible to prepare a variety of immunoliposomes for intravascular targeting. Here we discuss the results obtained with these liposomes in vitro, ex vivo, and in vivo.
2.2 Immunoliposome Targeting to Pathological Regions of the Vessel Wall
At present, it is commonly accepted that the initial stage of many vessel injuries, including atherosclerosis and thrombosis (coronary, among them), is a disruption of the integrity of the vessel wall's endothelial cover, leading to subendothelial denudation, which then serves as a strong stimulator of platelet activation and adhesion [1]. Naturally, it is tempting to think of early detection of such disruptions of the endothelium, and direct therapeutic action at these sites, to promote endothelial growth or to prevent platelet adhesion to the exposed collagen.
To prove the possibility of using targeted immunoliposomes as specific drug carriers to these areas, conjugates were obtained between liposomes and antibodies against the extracellular matrix antigens collagen, laminin, and fibronectin [2, 3]. Chazov et al. [2] grew human umbilical endothelial cells on fibrillar type I collagen in multiwell tissue culture plates to form an experimental model with partial reconstitution of the luminal surface of “normal” and “injured” vessel walls. The surface was imitated by confluent (normal vessel wall) or preconfluent (injured vessel wall) endothelial cell cultures grown on collagen. Specific recognition of collagen gaps in preconfluent culture was achieved with 14C-labeled liposome conjugates with antibody to type I collagen or with fibronectin, a protein capable of forming firm and specific complexes with collagen. Liposomes (100 nm) were prepared by sonication and subsequent sizing from a mixture of lecithin, cholesterol, and phosphatidyl ethanolamine in a 6 : 2: 2 molar ratio. Antibodies were coupled to liposomes via glutaraldehyde. The data obtained clearly demonstrated that anticollagen or fibronectin liposomes specifically recognize and bind collagen gaps between endothelial cells in preconfluent endothelial cell cultures grown on fibrillar collagen.
Similar results were obtained in other experiments involving the use of liposome conjugates with antibodies against laminin and fibronectin [4]. In this series of experiments [14C]cholesterol oleate or [3H]cholesterol liposomes were prepared from pure lecithin using the detergent dialysis method. For the incorporation into liposomes, corresponding antibodies were modified with palmitic acid residues [5] and incorporated into liposomes during detergent dialysis. Using [125I] immunoglobulins, it was established that the method used permits binding of a single 100-nm liposome with 30 to 40 protein molecules that are randomly distributed between the inner and outer sides of the monolayer of the liposomal membrane. The preservation of the specificity of antibodies upon their coupling to liposomes was demonstrated by measuring their binding to surfaces coated with laminin, fibronectin, or albumin. The incubation of antibody–liposome conjugates with substrate-coated matrices demonstrated that antibodies on liposomes (1) preserve their affinity, (2) maintain their specificity, and (3) are able to target liposomes to an appropriate antigen. The dissociation constant for liposome–antibody conjugate binding to the target was estimated to be in the range 1 to 10 × 10−9 M liposomes, which corresponds well to binding constants observed in the reaction of antigens with free antibody molecules.
Since immunomorphological studies of specimens prepared from human carotid arteries with anticollagen type I antibodies revealed large amounts of type I collagen in the subendothelium of lipid fibrous plaques, type I collagen exposed to the blood after plaque rupture can serve as a potential target for liposomal drug delivery. Smirnov et al. [6] conjugated [14C]cholesterol oleate–containing liposomes with bovine or human anticollagen type I antibodies, or perfused human plasma fibronectin in situ through segments of bovine, rabbit, or human arteries, where type I collagen exposure of the perfusate was achieved by partial denudation of the perfused vessel.
In all cases, perfusion with plain [14C] liposomes or with immobilized nonspecific rabbit IgG resulted in approximately equal association of liposomes with control and denuded areas in the arteries tested. However, fibronectin- or anticollagen antibody-targeted liposomes provided much higher association with the denuded area. Thus, liposomes can be targeted effectively to distinct areas of the pathological vessel luminal surface.
2.3 Liposome internalization by Endothelial Cells
In many cases, to generate the desired pharmacological effect, an appropriate drug must be delivered inside cells. This problem is of particular importance for cells with low phagocytic activity, such as endothelial cells, which are in direct contact with the blood and possess the unique property of exchanging macromolecular substances with underlying tissues. Hence, the targeting of biologically active substances to endothelial cells could result in a number of biological effects.
To prepare immunoliposomes and target the surface of human endothelial cells in culture, Trubetskaya et al. [7] used a monoclonal antibody, A25, against the human endothelial cell surface. Sonicated liposomes consisting mainly of dipalmitoyl phosphatidyl choline were used in these experiments. Antibodies were immobilized on the liposome surface via an avidin–biotin bridge. The internalization of [125I]immunoliposomes by human endothelial cells, followed by comparing total liposomal 125I radioactivity associated with cells, and cell surface–adsorbed liposomes was revealed using avidin–peroxidase. Initial immunoliposome binding to the cells at 4°C and subsequent endocytosis at 37°C resulted in the internalization of about 30% of the cell-associated liposomes and thus would permit intracellular delivery of pharmacologically active substances.
Endothelial cell adhesion molecules, expressed in response to inflammatory signals to then mediate recruitment of leukocytes to sites of inflammation, appear to be excellent targets for drug delivery systems. With the preparation and characterization of immunoliposomes directed against endothelial (E)-selectins, target sensitivity was demonstrated in a cell-containing in vitro model, where liposome binding to selectins under either static or simulated blood flow conditions was illustrated using fluorescence microscopy [8, 9]. Even under shear force conditions, liposomes accumulated selectively at selectin-containing cells. Furthermore, a need was demonstrated for poly(ethylene glycol) (PEG)–derived lipids to stabilize the liposomes sterically to prevent nonspecific liposome attachment to cells. E-selectin-directed immunoliposomes bound cumulatively to their target cells under the simulated shear force conditions of capillary blood flow for up to 18 h, and entrapped calceine was released into the cytoplasm [10].
It was also demonstrated that the pharmacokinetic behavior of immunoliposomes is strongly dependent on the antibody conjugation site on the liposome [11]. In naive rats, plain PEGylated liposomes displayed the longest blood circulation time, whereas the terminal-coupled immunoliposomes exhibited the fastest elimination. Liposomes containing the underivatized anchor molecules circulated nearly as long as did plain PEGylated liposomes, indicating that rapid elimination of the immunoliposomes can be attributed to the presence of antibodies. Various proteins of the extracellular matrix expressed on the surface of endothelial cells have been used as targets for the antibody-mediated delivery of the liposomes (see examples in Table 2.1).
Table 2.1 Immunoliposomes in Cardiovascular Targetinga
In related studies, the antibody against intercellular cell adhesion molecule 1 (ICAM-1), monoclonal antibody F10.2 was conjugated to liposomes to target to cells expressing the cell adhesion molecule ICAM-1. It was demonstrated that F10.2 immunoliposomes bind to human bronchial epithelial cells (BEAS-2B) and human umbilical vein endothelial cells (HUVECs) in a specific dose- and time-dependent manner [12].
As discovered recently, both the quantity of expressed adhesion molecules and the distribution of binding sites on the surface of endothelial cells play a role in the targeting process. Lipid rafts have received increasing attention as cellular membrane organelles contributing to the pathogenesis of several structural and functional processes, including cardiac hypertrophy and heart failure [13]. Sphingolipid- and cholesterol-rich microdomains of the plasma membrane present in cardiac myocytes are enriched in signaling molecules and ion-channel regulatory proteins. Clustering of cytokine-regulated cell-surface receptors, ICAM-1 and ELAM, on ECs and SMCs in lipid rafts may affect binding due to a nonhomogenous presentation of antibodies. It was shown that the localization of ICAM and E-selectin within lipid rafts was essential for binding of immunoliposomal vehicles labeled with antibodies against ICAM-1 and E-selectin [14]. These results suggest that antibody mobility and molar ratio play key roles in increasing receptor-mediated cell targeting.
2.4 Targeting of Atherosclerotic lesions for Tomographic Imaging
PEGylated paramagnetic and fluorescent immunoliposomes have been used to enable the parallel detection of the expression of molecular markers induced on endothelial cells using MRI and fluorescence microscopy. MRI is capable of three-dimensional noninvasive imaging of opaque tissues at nearly cellular resolution, while fluorescence microscopy can be used to investigate processes at the subcellular level. As a model for the expression of a molecular marker, HUVECs were treated with the proinflammatory cytokine tumor necrosis factor alpha (TNFα), to up-regulate the expression of the adhesion molecule E-selectin/CD62E [15]. E-selectin-expressing HUVECs were incubated with PEGylated paramagnetic fluorescently labeled liposomes carrying anti-E-selectin monoclonal antibody as a targeting ligand. Both MRI and fluorescence microscopy revealed the specific association of the liposomal MRI contrast agent with stimulated HUVECs. This study suggests that this newly developed system may serve as a useful diagnostic tool to investigate pathological processes in vivo with MRI.
Specific binding of the ICAM-1 conjugated liposomes to activated human coronary artery endothelial cells (HCAECs) were designed for early detection of atherosclerotic plaques by computed tomographic (CT) imaging [16]. Covalently attached anti-ICAM-1 monoclonal antibodies to PEGylated liposomes loaded with the contrast agent iohexol specifically bound to activated HCAECs in cell culture. Thus, iohexol-filled immunoliposomes have potential for use in CT angiography for noninvasive detection of atherosclerotic plaques, which are prone to rupture.
