Patricia A. D'Amore, Ph.D., M.B.A., F.A.R.V.O.
- Patricia A. D'Amore, Ph.D., M.B.A., F.A.R.V.O.
of Basic and Translational Research
Mass. Eye and Ear
Director of Research
Ankeny Scholar of Retinal Molecular Biology
Schepens Eye Research Institute
Charles L. Schepens Professor of Ophthalmology,
Professor of Pathology
Co-Director, HMS Ophthalmology AMD Center of Excellence
Vice-Chair of Basic Research, Department of Ophthalmology
Harvard Medical School
Dr. Patricia D’Amore grew up in Everett, Massachusetts and received a B.A. in 1973 from Regis College in Weston, MA. She then obtained a Ph.D. in Biology from Boston University in 1977, followed by a postdoctoral fellowship in Biological Chemistry and Ophthalmology at Johns Hopkins Medical School. In 1980, she joined the staff at Johns Hopkins as Assistant Professor of Ophthalmology. In 1981, she moved to the Folkman Lab at Children’s Hospital in Boston as an Assistant Professor of Pathology and today still remains a Research Associate in Surgery there. In 1987, Dr. D’Amore obtained an MBA from Northeastern University.
In addition to her scientific achievements, Dr. D’Amore has long been committed to her role as mentor and teacher. Since 1993, she has been a Member of the Biological and Biomedical Sciences Program, serving as Chair of the Admissions Committee, Chair of the Curriculum Committee, and Member of the Steering Committee. Also at Harvard Medical School she is an active member of the Minority Recruitment Committee, Joint Committee on the Status of Women, Faculty Committee on Student Research, Summer Honors Undergraduate Research Program (SHURP), Henry K. Beecher Prize in Medical Ethics Committee, Selection Committee for the Eleanor and Miles Shore Fellowship Program for Scholars in Medicine, and the Faculty Diversity Committee. Harvard Medical School awarded Dr. D'Amore the A. Clifford Barger Excellence in Mentoring Award in 2006, andthe Everett Mendelsohn Excellence in Mentoring Award in 2012.
Each year since 1994, Dr. D’Amore has been a Lecturer at the Marine Biology Laboratory in Woods Hole, Massachusetts where she teaches Research Update in Neuroscience for Neurosurgeons. In October, she will begin a term as a permanent member of the Biology and Diseases of the Posterior Eye Study Section.
In 1998, Dr. D’Amore became a Professor of Ophthalmology & Pathology at Harvard Medical School, and a Senior Scientist at the Schepens Eye Research Institute. In 1999, she was awarded the Jules and Doris Stein Research to Prevent Blindness Professorship. In 2000, she became the Co-chair of the Angiogenesis, Invasion & Metastasis Program at the Dana Farber/Harvard Cancer Center, and, in 2003, she became Chair. She also became the Associate Director of the Leder Human Biology & Translational Medical Program at Harvard Medical School in 2003. In 2004, Dr. D’Amore was elected to The Academy at Harvard Medical School. She is the founder of the Boston Angiogenesis Meeting, which will celebrate its 15th annual meeting this year. In 2005, she was the recipient of The Excellence Award at the Schepens Eye Research Institute and the Senior Scholar Award from the Research to Prevent Blindness. In 2012, Dr. D'Amore received 2012 Rous-Whipple Award from the American Society of Investigative Pathology and the Endre A. Balazs Prize from the International Society for Eye Research in 2014.
In May, 2014, the Association for Research in Vision and Ophthalmology (ARVO) announced that Dr. D'Amore would receive their highest award, The Proctor Medal. This prestigious award honors outstanding research in the basic or clinical sciences as applied to ophthalmology. This was the first ophthalmology-related award to honor non-clinicians in the field. Dr. D'Amore will presents the Proctor Award Lecture at the 2015 ARVO Annual Meeting and receives the Proctor Medal in a special ceremony.
Dr. D’Amore is currently Director of the Howe Laboratoy at Mass. Eye and Ear, as well as the Director of Research, Senior Scientist and the Ankeny Scholar of Retinal Molecular Biology at Schepens. Her research focuses on understanding the mechanism of vascular growth and development. She is particularly interested in the role of polypeptide growth factors such as VEGF and TGF-ß and in investigating the contribution of cell-cell interactions in the cells of the vasculature. She has over 211 publications to her credit, some of which have appeared in journals such as Nature Medicine, Journal of Clinical Investigation, Development, and Journal of Cell Biology.
Ph.D., 1977, Boston University
M.B.A., 1987, Northeastern University
2011, Program on Negotiation, Harvard Law School, Cambridge, MA
North American Vascular Biology Organization
"At the heart of vascular biology"
- Patricia A. D'Amore, Ph.D., M.B.A., F.A.R.V.O.
Conventional anti-cancer treatment has generally utilized chemotherapy. This type of treatment uses relatively non-specific agents that target growing cells. In contrast, the anti-angiogenic therapies should target only the growing blood vessels and therefore should have many fewer side effects.
Dr. Patricia D’Amore received her Ph.D. in Biology from Boston University in 1977. She was a postdoctoral fellow in Biological Chemistry and Ophthalmology at Johns Hopkins Medical School, and then became an Assistant Professor of Ophthalmology.
In 1981, she moved to the Children’s Hospital in Boston as Assistant Professor and is currently a Research Associate in Surgery. In 1998, she became Professor of Ophthalmology and Pathology at Harvard Medical School and a Senior Scientist at the Schepens Eye Research Institute. She is currently the Director of Research at the Institute and the Ankeny Scholar of Retinal Molecular Biology. Her research focuses on vascular growth and development, with an emphasis on blood-vessel growth in the retina. She believes that in order to decipher how disease processes occur you must first have a thorough understanding of the normal processes. Work conducted in her laboratory, and in collaboration with investigators at Mass Eye and Ear, formed the basis for the current use of anti-angiogenic therapies for diabetic retinopathy.
You study the vasculature. Can you describe it?
The vasculature can be compared to a plumbing system with the heart as the major pump and the blood vessels as the pipes that supply all parts of the body. The architecture of blood vessels is like a tree, with the central trunk called the aorta, and the very smallest branches called capillaries. It is at the level of the capillary that oxygen and nutrients diffuse out of the blood to nourish the tissues.
The term angiogenesis is in the news a lot. What does angiogenesis mean?
Angiogenesis comes from the terms “angio”, meaning blood, and “genesis” meaning birth. So angiogenesis is the growth of new blood vessels, specifically the smallest blood vessels (capillaries).
Why is there so much interest in angiogenesis?
Angiogenesis has become a topic of interest because of its central role in tumor growth. All tissues, including tumors, require a vascular supply to deliver oxygen and nutrients, and to remove CO2 and toxins. In the early 1970’s, Judah Folkman at Children’s Hospital in Boston hypothesized that tumor growth could be prevented by blocking the growth of blood vessels into tumors. More importantly, most blood vessels in the adult are not growing so it should be possible to develop therapies that target only the blood vessels growing into the tumors. With this, the idea of anti-angiogenic therapy was begun.
On the other hand, there are diseases that are characterized by insufficient blood flow. Coronary artery disease, in which the vessels that nourish the heart are blocked, is a very common example. In this case, the goal would be to stimulate the growth of new blood vessels that could circumvent the blocked arteries. Therapies aimed at growing new blood vessels are called pro-angiogenic.
How does anti-angiogenic therapy differ from the standard tumor treatments?
Conventional anti-cancer treatment has generally utilized chemotherapy. This type of treatment uses relatively non-specific agents that target growing cells. Though tumors cells would most certainly be killed by this treatment, it also destroys other dividing cells such as hair follicles (which is why patients lose their hair), the cells that line the stomach (which is the cause of the nausea), and the blood-forming cells of the bone marrow (which is why people can become anemic, or have reduced numbers of white cells). In contrast, the anti-angiogenic therapies should target only the growing blood vessels and therefore should have many fewer side effects.
Another very important difference between conventional chemotherapy and anti-angiogenic therapy is that patients often develop “resistance” to specific chemotherapies. Resistance develops when a subset of tumor cells acquires the ability to continue to grow in the presence of the chemotherapeutic agent. When this happens the tumor stops responding to the therapy and continues to grow; that is, the tumor becomes “resistant”. Different chemotherapies can be used but eventually the tumor develops a resistance to each one and the physician runs out of treatment options. This resistance is avoided by targeting the blood vessels instead of the tumor cells.
So what does angiogenesis have to do with eye disease?
New blood-vessel growth is a complication of a number of common eye diseases, including very common pathologies such as diabetic retinopathy and the wet form of macular degeneration. In both of these cases, new blood vessels grow in places where they normally do not grow. Furthermore, these new blood vessels are very leaky and as a result fluid can accumulate and disrupt vision.
Do tumor angiogenesis and eye angiogenesis have anything in common?
In fact, they have quite a bit in common. Perhaps not surprisingly, nature is very economical and uses the same molecules and mechanisms in many settings. A protein called vascular endothelial growth factor (VEGF) has been shown to be involved in both tumor angiogenesis and the angiogenesis associated with diabetic retinopathy and macular degeneration.
Are there any anti-angiogenic therapies available now?
The first anti-angiogenic therapy for cancer, called Avastin (made by Genentech), was approved for the treatment of colorectal cancer (in combination with chemotherapy) by the FDA more than two year ago. This drug is an antibody that can bind to VEGF and thereby block its action. The clinical trials that preceded its approval showed that, when used in combination with chemotherapy, it led to a four-month increase in survival when compared to chemotherapy alone. Since that time a number of trials have been conducted to assess its effectiveness against other kinds of cancer.
Encouraged by the promising results against cancer, and knowing that VEGF had been shown to play a role in angiogenesis in the eye, ophthalmologists began to treat their patients with wet macular degeneration with Avastin -- first intravenously and later by injection into the eye. Preliminary results to date have been extremely exciting; not only has the disease progression been halted but oftentimes there has been vision improvement. Genentech is currently testing a form of the anti-VEGF antibody designed specifically for ocular use, called Lucentis.
You mentioned pro-angiogenesis. Is there any on-going work to develop pro-angiogenic therapies?
Investigators are developing methods to deliver the angiogenic factor VEGF to tissues that need new blood vessels. This is being done for heart disease as well as for conditions where patients have insufficient blood flow to their legs (also called peripheral vascular disease).
- Patricia A. D'Amore, Ph.D., M.B.A., F.A.R.V.O.
Gopalan Gnanaguru, Ph.D.
Cindy Park-Windhol, Ph.D.
Wen Allen Tseng, Ph.D.
Jinling Yang, PhD
Formally Supervised Trainees
1994 Ako Bradford, Summer Honors Undergraduate Research Program
2002 Thalia Segal, Cornell University, Summer Intern
2003-2005 Alissa Cohen, Wellesley College, Summer Intern
2005 Kabir Matharu, Cornell University, Summer Intern
2004 Tomoki Kurihara, Williams College Medical Student, Osaka University School of Medicine
1986-1992 Kim Saunders, Ph.D., Program in Cell and Develop. Biology, Harvard Medical School, transferred to New Zealand
1989-1993 Sandra Dethlefsen, Ph.D., Department of Biology, Boston University, Scientist, Genzyme Corp., Cambridge, MA
1990-1994 Po-Tsan Ku, Ph.D., Program in Cell and Develop. Biology, Harvard Medical School, Sr., Product Mgr., Stratagene, La Jolla, CA
1991-1995 David Shima, Ph.D., Program in Biol. and Biomedical Sciences, Harvard Medical School, Prof., University College London
1994-2000 Claudia Garcia, Ph.D., Program in Biol. and Biomedical Sciences, Harvard Medical School, Research Associate, Washington University, St. Louis, MO
1994-2000 Eric Ng, Ph.D., Program in Biol. and Biomedical Sciences, Harvard Medical School, Lecturer, University College London
1994-2000 Lawrence Beck, M.D., Ph.D., Program in Biol. and Biomedical Sciences, Harvard Medical School, Instructor in Medicine, BU School of Medicine
1998-2003 Anne Goodwin, Ph.D., Program in Biol. and Biomedical Sciences, Harvard Medical School, Asst. Prof., North Adams State College, MA
1999-2005 Robyn Loureiro, Ph.D., Curriculum in Genetics and Molecular Biology,, University of North Carolina, In transition
2004-2007 Wendy Chao, Ph.D., Program in Biol. and Biomedical Sciences, Administrative Manager, Ophthalmology Research, Massachusetts Eye and Ear Infirmary, Boston, MA
2003-2007 Arindel Maharaj, M.D., Ph.D., Resident in Ophthalmology, Baylor Cullen Eye Institute, Houston, Texas
2007- 11 Knatokie Ford, Ph.D., Program in Biol. and Biomedical Sciences, HMS;AAAS Science and Technology Fellowship, Washington, D.C. (2012)
2009-12 Mandrita Bagchi (Datta), Ph.D., Program in Biol. and Biomedical Sciences, Harvard Medical School
2009- Wen Allen Tseng, Program in Biol. & Biomedical Sciences, HMS
1986-1988 Susan Connolly, Harvard Medical School, 1989, M.D. Magna cum laude, "Characterization of Vascular Development in Mouse Retina,” UCSF
1987-1988 Keith Paige, Harvard Medical School, 1989 M.D., Cum laude, Recipient of Harold Lamport Biomedical Best Paper Reporting, Original Research in Biomedical Sciences, "Retinoids as a Differentiating Agent in Endothelial Cells,” Plastic Surgeon, Virginia, Mason Medical Center, Seattle, WA
1987-1988 Gaylen Grayson, Harvard Medical School, 1988, Ophthalmology Fellow, University of Southern California
1992-1995 George Sakoulas, M.D., Harvard Medical School, 1995, Cum laude, "The Role of bFGF in Duodenal Ulceration: A New Mediator in an Old Disease,” Infect. Disease Specialist, Crystal Run Healthcare, Middletown, NY
1983-1989 Alicia Orlidge, Ph.D., Health care, Recipient of NIH-NRS Postdoctoral Fellowship 1984-1987, Self-employed, The Netherlands
1985-1988 Susan Braunhut, Ph.D., Recipient of NIH-NRS Postdoctoral Fellowship 1984-1986, Prof. of Biological Science & Biochemistry, UMass, Lowell
1986-1990 Deborah Damon, Ph.D., Recipient of NIH-NRS Postdoctoral Fellowship 1987-1989, Assoc., Prof. Pharmacology, University of Vermont
1989- 1994 Sandra Kostyk, M.D., Ph.D., Recipient of Physician Scientist Award 1991-1994, Asst. Prof., Neurology, Ohio State University, Columbus, OH
1990- 1993 Amlan RayChaudhury, Ph.D., Instructor in Pharmacology, Rush, Medical School, Chicago, IL
1991- 1995 Anne Gougos, Ph.D., Recipient of Research Fellowship, Heart and Stroke Foundation of Canada, Writer, Toronto, Canada
1991-1995 Andrea Dodge, Ph.D., Recipient of NIH-NRS Postdoctoral Fellowship 1991-1994, Instructor, North Shore Community College, MA
1994-1997 Karen Hirschi, Ph.D., Recipient of NIH-NRS Postdoctoral Fellowship 1994-1997, Professor of Pediatrics, Baylor College of Medicine, Houston, Texas
1994-1997 Cyndy Grosskreutz, M.D., Ph.D., Recipient of NIH Physician Scientist Award 1994-1999, Director of Research, Novartis, Cambridge, MA
1995-1996 Cecile Duplaa, Ph.D., Recipient of Fulbright Fellowship, Asst. Prof., INSERM, Bordeaux, France
1995-1996 Jianming Dong, MD, Ph.D., Neurology Resident, University of Washington, St. Louis, MO
1995-2000 Mary Elizabeth Hartnett, M.D., Professor of Ophthalmology, UNC
1996-2000 Qihong Xu, Ph.D., Scientist, Serono Laboratories, Norwell, MA
1996-1999 Rubai Ding, Ph.D., Staff Scientist, Berlex Labs, Richmond, CA
1998-2003 Diane Darland, Ph.D., Recipient of NIH-NRSA Postdoctoral Fellowship 1998-2001, Asst. Professor, University of North Dakota
2000-2002 Eric Ng, Ph.D., Lecturer, University College London
2001-2003 Markus Ramsauer, Ph.D., Research, Pharma, Basel, Switzerland
2001-2002 Alexandra Lappas, Ph.D., Ophthalmology, University of Aachen, Germany
2001-2007 Eric Finklestein, Ph.D., NRSA, 2004 – 1 F 32 CA105734, Research Associate, Syracuse Biomaterials Institute
2002-2009 Magali Saint-Geniez, Ph.D., Assistant Professor, Schepens Eye Research Institute
2003-2006 Scott Plotkin, M.D., Ph.D., Asst. Prof. in Neurology, MGH, Boston
2005-2006 Maruyama Kazuichi, M.D., Ph.D., Kyoto Prefectural Univ. of Medicine, Kyoto, Japan, Recipient of Gordon Research Conference Travel Award 2006
2006-2008 Brad Bryan, Ph.D., Asst. Professor, Texas Tech University
2006- 11 Tony Walshe, Ph.D., Recipient of Knights Templar Grant;Senior Scientist, Berg Biosystems, Natick, MA
2007-2009 Eiichi Sekiyama, M.D., Ph.D., Recipient of Bausch & Lomb Overseas Research Award; Clinician in Ophthalmology, Kyoto Prefectural University in Medicine
2007-2010 Nathaniel dela Paz, Ph.D., Research Scientist, La Jolla Bioengineering Institute, CA
2009-2011 Alisar Zahr, Ph.D., Recipient of MBED Fellowship, Sr. Scientist, Johnson & Johnson, Skillman, NJ
2009-2011 Sunita Patel-Hett, Ph.D., Scientist, Biogen, Cambridge, MA
2009-2010 Kati Kinnunen, Ph.D., Asst. Prof., University of Kuopio, Finland
2009-2012 Mandrita Bagchi (Datta), Ph.D., Associate Consultant, Decision Resources Consulting, Waltham, MA
2010- Joseph Arboleda, M.D., Ph.D.
2011- Jinling Yang, Ph.D.
2011- Leo Kim, M.D., Ph.D., K12 Recipient
1983-1984 Aubrey Galloway, M.D., Professor of Surgery, NYU
1985-1987 Robert W. Thompson, M.D., Professor of Surgery, University of Washington, St. Louis, MO
1987-1988 Hank Frissora, M.D., Surgeon, BIDMC, Boston
1994-1996 Stephanie Rohovsky, M.D., Harvard-Longwood Research Training Fellow, Surgeon, BIDMC, Boston
1997-2000 Louis Nguyen, M.D., Harvard-Longwood Research Training Fellow,, Asst. Professor of Surgery, Brigham & Womenʼs Hospital, Boston
Dissertation Advisory Committees:
1983-1987 Christine Kelley, Ph.D., Department of Biology, Boston University
1983-1987 John Doukas, Ph.D., Department of Biology, Boston University
1989-1991 Aileen Healy, Ph.D., Department of Anatomy and Cell Biology, Tufts Medical School
1989-1991 Elizabeth Neuman, Ph.D., Program in Cell and Developmental Biology, HMS
1991-1994 Thomas White, Ph.D., Program in Cell and Developmental Biology, HMS
1989-1995 Christa Merzdorf, Ph.D., Program in Cell and Developmental Biology, HMS
1994-1995 Hwai-Jong Cheng, Ph.D., Program in Biological and Biomedical Sciences, HMS
1993-1996 Joe Gabriels, Program in Biological and Biomedical Sciences, HMS
1994-1996 Mark Throop, Program in Biological and Biomedical Sciences, HMS
1994-1998 Laura Demolino, Department of Anatomy and Cell Biology, Tufts Medical School
1995-1998 Marilyn Fitzgerald, Program in Biological and Biomedical Sciences, HMS
1999-2001 Rani Dhavan, Program in Biological and Biomedical Sciences, HMS
2000-2005 Leslie Frieden, Ph.D., Program in Biological and Biomedical Sciences, HMS
2003-2009 Julia Sero, Ph.D., Program in Biological and Biomedical Sciences, HMS
2003-2008 Joseph Arboleda, Ph.D. (Chair), Program in Biological and Biomedical Sciences, HMS
2005-2007 Kush Pumar, M.D., Ph.D. (Chair), Program in Biological and Biomedical Sciences, HMS
2006-2009 Corrine Nielsen, Ph.D.
2007-2009 Scott Potenta, M.D., Ph.D.
2008-2010 Vida de Arce, PhD. Program in Biological Sciences in Dental Medicine
2011- Kelli Carroll, Ph.D. Program in Biological and Biomedical Sciences, HMS
2011-2013 Peter Yang, Ph.D.Program in Biological and Biomedical Sciences, HMS
2011- Cholsoon Jang, Ph.D. Program in Biological and Biomedical Sciences, HMS
2011- Teresa Peterson, Ph.D. Program in Biological and Biomedical Sciences, HMS
2013- Jamie Lahvic Program in Biological and Biomedical Sciences, HMS
- Patricia A. D'Amore, Ph.D., M.B.A., F.A.R.V.O.
Cell-cell Interactions in the Retinal Vasculature
The major goal of this project is to understand the mechanisms that regulate vessel assembly and stability.
Molecular Bases of the Eye Disease
The goal of this project is to train the next generation of scientists who will address the problems of eye disease by identifying new means of diagnosis, prevention and treatment.
Role of RPE-derived VEGF in Choroid Development & Stability
The goal of this study is to investigate the role of VEGF in choroidal vascular development and stability.
Notch-mediated Cell-cell Interactions in the Pathophysiology of Diabetic Retinopathy
On-going Research Projects/In-depth Analysis
Cell-cell Interactions in the Regulation of Capillary Growth and Stability
New vessels form de novo (vasculogenesis) or from pre-existing vessels (angiogenesis) in a process that involves the interaction between endothelial cells (EC) and pericytes/smooth muscle cells (SMC). One basic component of this interaction is the endothelial-induced recruitment, proliferation and subsequent differentiation of pericytes or SMC. We have previously demonstrated that transforming growth factor b (TGFb) induces the differentiation of C3H/10T1/2 (10T1/2) mesenchymal cells toward a SMC/pericyte lineage. We tested the hypothesis that TGFb not only induces SMC differentiation, but stabilizes capillary-like structures in a three-dimensional (3D) model of in vitro angiogenesis. 10T1/2 cells and EC in Matrigel™ were used to establish cocultures that formed cord structures that were reminiscent of new capillaries in vivo. Cord formation was initiated within 2-3 hr after plating and continued through 18 hr after plating. In longer cocultures the cord structures disassembled and formed aggregates. 10T1/2 cell expression of proteins associated with the SMC/pericyte lineage, such as smooth muscle actin (SMA) and NG2 proteoglycan, were upregulated in these 3D cocultures. Application of neutralizing reagents specific for TGFb blocked cord formation and inhibited expression of SMA and NG2 in the 10T1/2 cells. These results indicate that TGFb mediates 10T1/2 differentiation to SMC/pericytes in the 3D cocultures and that association with differentiated mural cells is required for formation of capillary-like structures in Matrigel™.
To further understand the mechanism through which pericytes might stabilize vessels, we tested the hypothesis that differentiation of mesenchymal cells to pericytes/SMC is accompanied by vascular endothelial growth factor (VEGF) expression, which mediates EC survival. Coculture of EC and 10T1/2 cells (multipotent mesenchymal cells), which led to 10T1/2 differentiation to a pericyte fate, accompanied the induction of VEGF expression. The increase in VEGF depended on contact between EC and 10T1/2 cells. The VEGF induction was due to the action of TGFb, as coculture of EC smad3-/- mouse embryo fibroblasts did not yield elevated VEGF. A majority of the VEGF in the cocultures was cell- and/or matrix-associated via heparan sulfate proteoglycans; treatment of the cells with high salt, protamine, heparin or suramin led to significant VEGF release. Inhibition of VEGF in the cocultures led to a 75% increase in EC apoptosis, relative to coculture controls, indicating a role for VEGF in EC survival. These observations indicate that differentiated pericytes produce VEGF, which acts in a juxtacrine/paracrine manner as a survival and/or stabilizing factor for EC in newly formed vessels.
The capillary-like tubes formed in Matrigel, as described above, form rapidly (within 6 hr) but the structures are short-lived (18-24 hr). During the past year we worked to develop a novel 3D coculture system that will produce capillary-like structures that are stable over extended time periods, which will allow us to test the stabilizing effect of pericytes on EC forming capillaries. For these studies, we induced apoptosis in 10T1/2 cells in co-culture and looked at the consequences on the remaining bovine retinal endothelial cell (BREC)-capillary-like structures (CLS). Since a control in which EC cells alone form CLS was necessary, we tested various matrices for the basis of the 3D gel and found that in Vitrogen (collagen I and III), BREC form CLS in the absence of 10T1/2 cells if appropriate growth factors are added. In the absence of added growth factors, EC underwent cell death. Addition of VEGF induced CLS. Addition of basic fibroblast growth factor (bFGF) along with VEGF resulted in the formation of a vascular network similar to that formed in BREC-10T1/2 cells co-cultures. Thus, VEGF seems to be the differentiation factor that induces capillary-formation, whereas bFGF acts mainly as a proliferation factor, to expand a complex network.
We next determined if CLS formed in BREC-10T1/2 cell co-cultures were more stable than CLS formed from solo-cultures of BREC, and if the 10T1/2 cells/pericytes could protect the EC from pro-apoptotic stimuli. TGFb1 had been shown to induce endothelial apoptosis; the addition of exogenous TGFb1 induced cell death in BREC in solo-culture but not in co-culture with 10T1/2 cells.
It seemed clear that the actions of TGFb depend on the context in which the factors act. TGFb1 was known to be produced and activated in co-cultures where we suspected it mediated aspects of vessel stabilization. On the other hand, we showed that addition of TGFb1 to BREC (in the absence of 10T1/2 cells-pericytes) induced EC apoptosis. Thus, it appears that for TGFb1 to be involved in the dynamic process of capillary-stabilization it has to be balanced by another factor(s). Current studies are aimed at elucidating what other factors, if any, are involved in vessel stabilization
VEGF is critical for normal development of the vascular system in mouse embryos. Murine VEGF exists as at least three homodimeric isoforms as a result of mRNA alternative splicing; they include VEGF120, VEGF164 and VEGF188. These three isoforms have different affinities for heparan sulfate as well as for the three known VEGF receptors: Flk-1, Flt-1, and neuropilin-1, suggesting that differential receptor binding and/or extracellular localization may allow the different VEGF isoforms to play distinct roles in vascular development. To address the possibility of distinct functions for the individual isoforms, we have generated lines of mice that each expressed single VEGF isoforms. Mice that expressed only VEGF120 had the most dramatic phenotype. Though they survived to term, they died immediately after birth, presumably due to pulmonary dysfunction. VEGF188 mice lived to term and survived through adulthood but had a variety of non-lethal vascular defects. We used these animals to study the role of various VEGF isoforms in tissue and organ development.
Retinal vascular development was studied in mice expressing VEGF120, VEGF164, or VEGF188. VEGF164/164 mice appeared normal and healthy, and had normal retinal angiogenesis. In contrast, VEGF 120/120 mice exhibited severe defects in outgrowth and patterning of retinal vessels. VEGF188/188 mice displayed normal outgrowth of retinal veins, but impaired retinal arterial development. Neuropilin-1, a receptor for VEGF164, was predominantly expressed in developing retinal arterioles.
As VEGF120/20 mice survived until after birth, they offered an attractive opportunity to study the role of VEGF during bone development. Analysis of cartilage vascularization of wild-type and VEGF120/120 mice identified two key differences. First, at embryonic day 14.5 there was a lack of blood vessels surrounding the cartilage, and second, at E15.5 there was a lack of vascular invasion into hypertrophic cartilage. At E13.5, strong VEGF expression was detected in the perichondrium and the surrounding tissues. This expression, in combination with the known VEGF expression in hypertrophic chondrocytes at E15.5, provided a new understanding of cartilage vascularization and defined a role for VEGF in the developmentally regulated patterning of skeletal vascularity. The sequence of appearance of cartilage differentiation markers identified a delay at E14.5 of cartilage maturation in VEGF120/120 mice, further suggesting a role for VEGF in maintaining the normal chondrocyte differentiation program. Finally, reduction in both endochondral and membranous bone formation in VEGF120/120 mice suggested a role for VEGF in osteoblast function. Enhanced bone formation in calvarial organ culture after treatment with VEGF demonstrated that VEGF has a stimulatory effect on osteoblastic activity during skeletal development. Thus, we have described a novel two-step model for VEGF controlled vascularization of skeletal elements and have provided evidence for a role of VEGF in osteoblastic regulation.
Lung development was also defective in VEGF120 mice. Lung vessel development was studied by scanning electron microscopy of Mercox casts of lung vasculature. Airway and air-blood barrier development was analyzed by light microscopy, transmission electron microscopy, immunohistochemistry and morphometry. In all VEGF120/120 fetuses and pups, lung vascular casts were smaller and less dense compared to those of 120/+ and wild type (wt) littermates. Although in all three genotypes the generation count of preacinar vessels was similar, the most peripheral vessels had thicker profiles and were more widely separated in 120/120 fetuses of all ages, compared to 120/+ and wt littermates. In addition, 120/120 animals had fewer air-blood barriers and a decreased air-parenchyma ratio compared to 120/+ and wt littermates. These data indicate that the absence of VEGF164 and 188 isoforms impaired lung microvascular development and delayed airspace maturation, and indicate an essential role for heparin-binding VEGF isoforms in normal lung development.
- Patricia A. D'Amore, Ph.D., M.B.A., F.A.R.V.O.
Click here for a PubMed list of abstracts formatted by BioMed Central
From 211 Peer-Reviewed Publications in print or other media, 66 reviews, chapters, monographs and editorials and 4 books.
Sekiyama E, Saint-Geniez M, Yoneda K, Hisatomi T, Nakao S, Walshe TE, Maruyama K, Hafezi-Moghadam A, Miller JW, Kinoshita S, and D’Amore PA. Heat treatment of retinal pigment epithelium induces production of elastic lamina components and anti-angiogenic activity. FASEB J. 2012 Feb: 26(2): 567-75. Epub 2011 Nov. 8. PMID: 22067481.
Panigrahy D, Edin ML, Lee CR, Huang S , Bielenberg DR, Butterfield CE, Barnés CM, Mammoto S, Mammoto T, Luria A, Benny O, Chaponis DM, Dudley AC, Vergilio J, Pietramaggiori G, Scherer-Pietramaggiori SS, Short SM, Seth M, Le HD, Kalish B, Puder M, Lih FB, Tomer KB, Ingber DE, Hammock BD, Falck JR, Manthati VL, Kaipainen A, D’Amore PA, Kieran MW, Zeldin DC. Epoxyeicosatrienoic acids control angiogenesis-dependent regeneration, cancer, and metastasis, J Clin Invest, 2012 Jan 3; 122(1):178-91 doi: 10 1172/JC158128. Epub 2011 Dec 19. PMCID: PMC3248288.
Ford K, Saint-Geniez M, Walshe T, Zahr A, D’Amore P. Expression and role of VEGF in the adult retinal pigment epithelium. Invest Opthalmol Vis Sci, 2011, 52:9478-9487. PMCID: PMC3250352.
Ford KM, D’Amore PA. Molecular regulation of vascular endothelial growth factor expression in the retinal pigment epithelium. Molecular Vision, 2012, 18:519-527. PMCID: PMC328425.
Paz NG, Walshe TE, Leach LL, Saint-Geniez M, D’Amore PA. Role of shear-stress-induced VEGF expression in endothelial cell survival. J Cell Sci, 2012,125: 831-843. PMCID: PMC3311927.
K. Maruyama, Toru Nakazawa, C. Cursiefen, Y. Maruyama, N. Van Rooijen, P. A. D’Amore and S. Kinoshita. The maintenance of lymphatic vessels in the cornea is dependent on the presence of macrophages. Invest Ophthalmol Vis Sci, 2012, 10.1167/iovs.11-8010. PMID: 22511631.
Ford KM, Saint-Geniez M, Walshe TE, D’Amore PA. Expression and role of VEGF-A in the ciliary body. Invest Ophthalmol Vis Sci, 2012, 53(12):7520-7. PMID: 23081980.
Jia D, Hasso S, Chan J, Filingeri D, D'Amore P, Rice L, Pampo C, Siemann D, Zurakowski D, Rodig S, and Moses M. Transcriptional repression of VEGF by ZNF24: mechanistic studies and vascular consequences in vivo, Blood, 2012, 10.1182/blood-2012-05-433045. PMCID: PMC3557646.
Tseng WA, Thein T, Kinnunen K, Lashkari K, Gregory MS, D’Amore PA, Ksander BR. NLRP3 inflammasome activation in retinal pigment epithelial cells by lysosomal destabilization: implications for age-related macular degeneration. Invest Ophthalmol Vis Sci. 2013; 54:110-120. PMCID: PMC3544415.
Bielenberg DR, D’Amore PA. All vessels are not created equal. AM J Pathol., 2013;(4):1087-91. PMID:23422091.
Bagchi M, Kim LA, Boucher J, Walshe TE, Kahn CR, and D’Amore PA. Vascular endothelial growth factor is important for brown adipose tissue development and maintenance. FASEB J, 2013. (8):3257-71. PMID: 23682123.
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