Hooked on Research
words by Eve Jacobs / photograph by Andrew Hanenberg
avid B. Seifer’s curiosity knows few bounds. In fact, his persistent exploration of the unknowns surrounding human
fertility and infertility has led him to a finding that those in the know say may become the best family planning tool available. Intrigued? Well, so are the many women now pushing child-bearing to age 35 and older, when pregnancy can seem to be an illusive dream.
Passion defines Seifer’s approach to his life’s work and exuberance for its day-to-day challenges underlies everything he does. It surfaces in a restless energy that belies his many years of dedicated single-mindedness to a challenge that appeared to be unyielding.
“Hooked” on research during his undergraduate years at Tufts, when he spent several summers in labs at Tufts and Harvard Medical School, and “reeled in” during his independent study program at the University of Illinois Medical School, when he spent close to a year at The Children’s Hospital of Philadelphia doing clinical research, Seifer found in the collaborative-rich laboratory environment an answer to a personal quest. The collegiality among fellow investigators — who share a joy in working to solve seemingly unsolvable scientific puzzles independently and collaboratively — appealed to him. “No one person has enough expertise to solve complex scientific problems alone,” he comments.
During year two of his surgery residency — on what seemed like a very long rotation in neurosurgery — at the University of Southern California, he realized that working with patients who could not communicate was not his thing. Being a man of action, he switched during his second year of surgery to an Ob/Gyn residency at Stanford, a field he saw as offering opportunities for collaborative relationships with both patients and fellow researchers.
It was at Yale, during his fellowship training in reproductive endocrinology and infertility, that serendipity gave him a head-start on what has become his life’s work. It has provided him the opportunity to blend an unremitting focus on his research goal with more than 20 years of dedication to hands-on patient care.
"Sometimes research is making connections between things that do not seem particularly related,” he says. “Making these connections between what may appear random gives you insight into why things work the way they do. It makes you feel good — that there’s a purpose to this, a reason why certain processes and strategies are successfully conserved across different species over hundreds and thousands of years.”
These connections are what truly intrigue this physician-scientist — how similar processes go on in the brain and the ovary, for instance. “The more you appreciate science, the more you appreciate nature and the natural order of the world,” he says. “There is a purpose to most designs.”
His desire to make those connections and a determination to expand upon the limitations of current medical therapies have been Seifer’s inspirations. “You hit a wall and can’t initially solve the problem,” he explains, “and it motivates you to approach the problem differently, to think differently, to reassess your basic assumptions and sometimes to design new tools.”
In 1990, the then Yale fellow attended a lecture in which the presentation addressed the role of antimullerian hormone (AMH) in the rat follicle. A light bulb went on in the young doctor’s brain and he approached the lecturer: “Maybe this protein that has a role in a rat egg is important in human ovarian physiology as well,” he ventured. That question was the springboard for the investigation and ultimate discovery of AMH in human follicular fluid and the beginning of a meaningful research collaboration that continues to this day.
Seifer calls himself lucky to have come across doctors working in the field of infertility in the early days of IVF (in vitro fertilization).Witnessing such an amazing leap in medical technology captured his imagination. He came to understand that IVF would be an emerging field of medicine that could combine clinical care with cutting edge technology for healthy women wanting to have families. His chosen field of reproductive endocrinology, he says, is full of positives, in particular helping to take part in a process that can transform patients’ lives and significantly impact upon their futures.
He has set himself to tackle what he sees as one of the most critical issues in the field of reproduction. “Ovarian aging occurs at a much quicker pace than the rest of the body,” he says. Starting out looking at reproductive aging in rats, he quickly moved on to studying follicular fluid and granulosa cells that were being discarded — at that time — when physicians did egg retrievals. “I thought to myself,” he remembers, “the cells are there for a reason.” In other words, it begged to be looked at seriously.
“As women get older,” he ruminated, “what’s different about the egg beyond the DNA hardware? It must be influenced by signals — in the form of proteins. Some ovaries act younger than their chronological age, others act older.” He spent the next 15 years looking at these protein signals and their significance, how they reflected what was going on in the follicle and influenced what was going on in the rest of the ovary and the egg.
His more refined question became: “How do we get a sense for what a woman’s egg supply is in real time without using invasive methods?” Again — AMH appeared to be pivotal, since Seifer and colleagues discovered that AMH is directly tied to egg production. In fact, it is the earliest biomarker of ovarian aging. The hormone is produced by early stage ovarian follicles, declines with age and its levels can be measured with a simple blood test.
Since 2002, there have been many clinical studies of AMH, which have demonstrated its value as a predictive tool. “Other fertility tests confirm that menopause has happened,” explains Seifer. “But AMH appears to anticipate menopause by several years,” — giving women a window of opportunity for having children.
“It’s useful in making clinical decisions about egg supply and a reasonable prediction of when menopause may occur,” he states. The discovery has been patented and licensed to Beckman Coulter, a major U.S. diagnostic company. Use of AMH to assess fertility has become widespread in Europe, Asia, and Australia, and is catching on in the U.S., where the tests are run by major clinical laboratories and used throughout this country.
Based on its growing popularity both here and abroad, Seifer proudly anticipates: “In combination or by itself, AMH will be one of the primary ways that physicians and patients will determine family planning.” An excellent example of how perseverance in pursuing the answers to a scientific puzzle — over many years — can yield a discovery that seriously impacts the lives and futures of generations to come.
For nearly two decades, I have dedicated my research to a combination of basic, translational and clinical science; and have focused primarily on the discovery of new granulosa cell proteins and the definition of their respective roles in the function of the normal and aging human preovulatory follicle. This research has led to a better understanding of the physiology of diminished ovarian reserve as well as to novel clinical applications which may contribute to improved success with reproductive treatments for millions of couples struggling with infertility.
My co-workers and I initially investigated components of the aging ovarian follicle. The overall goal of this work was to investigate age-dependent changes in the human granulosa cell. Our working hypothesis was that reproductive aging results in an ovarian follicle containing somatic cells (granulosa cells) and germ cells (oocytes) that are of compromised quantity (diminished ovarian reserve) and quality as compared to their respective components in younger women. We then described alterations in the life cycle and secretory processes of granulosa cells that reflect age-related changes in granulosa cell competence and are concomitant with diminished ovarian reserve and the decline in female fecundity. These changes involve alterations in granulosa steroidogenesis, growth factor production (including inhibin B and MIS/AMH), cell cycle expression, and apoptotic and gene expression changes.
This research led to two translational advances. The first was a better understanding of the aging granulosa cell and, in turn, the aging ovarian follicle responsible for diminished ovarian reserve. This fundamental information has allowed greater insight into cellular molecular events that precede the perimenopausal transition. The second advancement was the clinical use of granulosa cell proteins as serum markers of a woman’s ovarian reserve. Inhibin B — reported in 1997 — and mullerian-inhibiting substance (MIS; also known as antimullerian hormone or AMH) — reported in 2002 — are two granulosa cell proteins that we first described in serum as predictive of diminished ovarian reserve and reduced oocyte yield in women undergoing IVF. This second advancement was a natural extension of having studied human granulosa cells in a variety of different contexts and different model systems during our initial years of granulosa cell investigation.
These basic investigations led to the insight that granulosa cell products, when measured in serum, could be reflective of the direct status of a woman’s ovarian reserve and have important translational clinical use. Their measurement could be more informative than conventional serum FSH alone. This could potentially allow clinicians to better counsel couples regarding their likelihood of success of treatment and assist clinicians in their choice of what particular medications to choose for an optimal response.
For the last eight years, we have also been investigating a family of ovarian growth factors, known as neurotrophins, which we discovered to be present in the adult human preovulatory follicle. The family of neurotrophins include brain-derived neurotrophic factor (BDNF), neurotrophin-4/5 (NT-4/5), neurotrophin-3 (NT-3), and nerve growth factor (NGF). We have utilized both human and mouse models to investigate the neurotrophin site of secretion and potential function in promoting oocyte maturation as well as their basic roles in ovarian physiology. These studies indicate that neurotrophins, if not obligatory, may facilitate regulation of oocyte physiology, including oocyte development within the preovulatory follicle. Our basic research shows promise of leading to areas of translational applications in both in vitro maturation of immature oocytes and in pathophysiologic conditions such as polycystic ovarian disease. These findings may eventually lead to new opportunities for treatment of infertility and to improved methods of contraception.
Much of our work has been made possible through a combination of grants from private institutional foundations and NIH funding over almost 20 years. The products of this research (the use of serum MIS/AMH in assessing ovarian reserve and the use of ovarian neurotrophins to enhance maturation of immature oocytes in culture) have been recognized by the United States Patent Office as original and novel, resulting in four granted U.S. patents and eight pending world-wide patents for the academic institutions where this work was accomplished. More important is the amplification effect of this work upon investigators world–wide who have been interested in continuing investigation along these as well as other divergent lines of reproductive science research that have resulted from these novel discoveries.
This amplification effect has also been realized through teaching and working side by side with hundreds of medical students and residents over the past 20 years. Some of this effort has focused on developing an appreciation of how to critically think about medicine using research as a model for discovery and evaluation of mechanisms and treatments of disease. My involvement as a consultant and collaborator for the NIH funded Women’s Interagency HIV Study (WIHS), the largest ongoing multicenter prospective cohort study of HIV infection and related health conditions among HIV infected women in the U.S., has allowed for opportunities to study the impact of race and ethnicity upon female reproductive aging.