Speakers: Toufan Parman (Sangamo Therapeutics); Jamie DeWitt (East Carolina University); E. Sidney Hunter (US EPA); Aileen Keating (Iowa State University); Thomas B. Knudsen (U.S. EPA); Marc Luetjens (Labcorp); Paul Bushdid (Labcorp Greenfield); Ann Baker (Labcorp Madison); Donald G. Stump (Charles River Laboratories); Alan Hoberman (Charles River Laboratories); Adrian Tomkinson (Gilead Sciences)
Organizers: Doris Zane (Gilead) and Toufan Parman (Sangamo)
Date: 2021-11-03- 11/04/2021
Time: 8:30-12:30 Pacific Time
Registration fee: (USD):
Location: Online via Zoom
Major Sponsor:
Vendor show vendors registered to date:
Registration: http://www.PBSS.org
Registration deadline:2021-10-29  (it will close sooner if the seating cap is reached)

About the Topic

In this PBSS Reproductive Toxicology 2-Day Workshop, we will be covering a broad range of topics including the reproductive immune system, early reproductive development, alternative reproductive models (in vitro models), male and female fertility assessment, reproductive and developmental toxicology testing, and bone formation. We have dynamic presenters representing Academia, EPA, Industry and Contract Research Organization.

Early Embryonic Development & Methodology

November 3, 2021 - 8:35 AM-1:35 PM Pacific Time

8:35 AM-8:45 AM       Introductions/Welcome (Shichang Miao, PhD, PBSS President)

8:45 AM-9:00 AM       Background/Overview on Reproductive Toxicology (Toufan Parman, PhD, DABT, Sr. Director, Nonclinical Safety Evaluations, Sangamo Therapeutics)

9:00 AM-10:00 AM          Tools for detecting alterations to the developing immune system (Jamie DeWitt, PhD, DABT, Professor, Department of Pharmacology and Toxicology, East Carolina University)

10:00 AM-11:00 AM        From Fertilization to Neural Tube and Somite formation (E. Sidney Hunter, III, PhD, Acting Director, Biomolecular and Computational Toxicology Division, US EPA: Embryology)

11:00 AM-11:15 AM   Break

11:15 AM-12:15 PM   In vitro models to decipher ovotoxic modes of action (Aileen Keating, PhD, Professor, Department of Animal Sciences, Iowa State University)

12:15 PM-1:05 PM      Translatability of Cell-Based and In Silico Models of Developmental Toxicity (Thomas B. Knudsen, PhD, Developmental System Biologist, Computational Toxicology and Bioinformatics Branch, U.S. EPA)

1:05 PM-1:35 PM        Panel Discussion/Conclusions

 
Regulatory Trends & Case Studies

November 4, 2021 - 8:30 AM-1:00 PM Pacific Time 

8:30 AM-8:45 AM       Recap/Highlights of Day 1 (Doris Zane, PhD, DABT, Executive Director, Nonclinical Safety and Pathobiology, Gilead Sciences)

8:45 AM-9:45 AM       Consequences of ICH Guidelines on DART and JAS Toxicity Studies in Primates (Marc Luetjens, PhD, Senior Study Director, Global NHP DART in Muenster, Labcorp); Q&A: Paul Bushdid, Executive Director of DART, Labcorp Greenfield; Ann Baker, Study Director & NHP DART Specialist, Labcorp Madison

9:45 AM-10:45 AM     Male and Female Fertility Assessment (Donald G. Stump, PhD, DABT, Principal Director of Toxicology, Charles River Laboratories)

10:45 AM-11:00 AM   Break

11:00 AM-11:50 AM   Cell and Gene Therapy Products-What should we do? (Alan Hoberman, PhD, DABT, Fellow ATS, Charles River Laboratories: Reproductive and Developmental Toxicology Testing)

11:50 AM-12:30 PM      Endochondral Ossification in Developing Long Bones of F1 Offspring Following Administration of Andecaliximab to F0 Dams During Gestation and Lactation (Adrian Tomkinson, PhD, Gilead Sciences)

12:30 PM-1:00 PM        Panel Discussion/Conclusions

 

November 3, 2021 Speakers

 

Jamie DeWitt, PhD, DABT

Professor, Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC.

Title: Tools for detecting alterations to the developing immune system

Development of the immune system is a complex process that involves not only interactions among developing cells and tissues with internal factors such as gestational, lactational, and pre- and post-pubertal events, but with external factors such maternal exposures. When interactions with these factors are disturbed, developmental immunotoxicity (DIT) can result. DIT is defined as adverse effects on the immune system resulting from exposure to environmental risk factors prior to adulthood. Common tools for investigating DIT include observational measures (i.e., immunophenotype and lymphoid organ histopathology) and functional assessments (i.e., antigen-specific antibody responses, delayed-type hypersensitivity, host resistance, cell cytotoxicity and proliferation). Assessment of effects of exogenous agents on developing organisms is highly dependent on the developmental stage of exposure as well as the developmental stage of the immune system when it is evaluated. The use of DIT tools may thus vary given whether exposure occurs during gestation, lactation, or the juvenile period or across several developmental periods. It is therefore critical that DIT assessments are conducted with different developmental stages of exposure/assessment in mind as well as relative advantages and disadvantages of the tools themselves.

 

Sid Hunter II, Ph.D.

Chief of the Advanced Experimental Toxicology Models Branch, Biomolecular and Computational Toxicology Division, Center for Computational Toxicology in the Office of Research and Development in the U.S. Environmental Protection Agency (EPA)

TITLE: Embryology: From Fertilization to Neural Tube and Somite formation.

Embryogenesis progresses from the fusion of the egg and sperm through many critical processes to establish the embryo proper. This lecture will describe and discuss those processes. Fusion of the sperm and egg establishes the one cell zygote. Continued cellular division, initiation of zygotic gene expression and cellular specification occurs during the pre-implantation period with the formation of the blastocyst. The process of implantation occurs with the attachment, penetration, and implantation of the blastocyst into uterine tissues. The blastocyst has two distinct cell types, trophoblasts and the inner cell mass. Trophoblast cells form placental anlagen. Differentiation of the inner cell mass ultimately forms the three “germ cell” lineages and layers in the embryo. The three germ cell layers, ectoderm, mesoderm and endoderm, contribute to establishing the body plan and distinct cell types and structures. This period of gestation is call organogenesis. The neuroectoderm, derived from ectoderm, begins as a sheet of cells that close into a tube giving rise to the neural tube and ultimately, brain and spinal cord. Somites are specialization of the mesoderm that establish block-like structures throughout the body of the embryo and form vertebrae and other segmented structures. Other organ systems, such as the cardiovascular system, are being established during this window of development. With the closure of the neural tube and establishment of somites, the embryo has established its characteristic body plan and awaits further development and histogenesis of tissues and organs. This abstract does not necessarily reflect U.S. EPA policy.

 

Aileen F. Keating, Ph.D.

Associate Professor, Department of Animal Science, Iowa State University

Title: In vitro models to decipher ovotoxic modes of action

Exposure to female reproductive toxicants can have several effects, including but not limited to, reduction of the ovarian follicular reserve, alterations to follicle growth, germline and somatic cell DNA damage, endocrine disruption, anovulation, pregnancy loss and lactational impacts. Several in vitro methods have been developed to assess direct ovarian effects of toxicants including whole ovary ex vivo culture, spontaneously immortalized and/or primary granulosa cells, whole follicle culture, 3-dimensional follicle culture, and ovary-on-a-chip. The application of these methods and the benefits and drawbacks of each will be discussed and related to toxicological application. 

 

Thomas B. Knudsen, Ph.D.

Developmental Systems Biologist, Computational Toxicology and Bioinformatics Branch, Biomolecular and Computational Toxicology Division, Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency

TITLE: Translatability of Cell-Based and In Silico Models of Developmental Toxicity

High-throughput in vitro assays offer a promising alternative to pregnant animal studies for assessing developmental toxicity of chemicals. Varying cells used in high-throughput screening assays have unique properties of self-renewal, pluripotency, and self-organization which help them to be excellent models of the developing embryo, particularly during early stages when the basic body plan is ‘decoded’ from the genomic blueprint. Many studies have shown positive predictive value of these cell lines for detecting developmental toxicity potential; however, translatability to pregnancy and development will require integrative computational models that recapitulate the full complementation of developmental pathways, maternal-placental toxicokinetics, and toxicodynamics of an exposed embryo. Research under EPA’s Virtual Tissues Models is investigating the translatability of diverse cell-based platforms and computer models to evaluate effects of thousands of chemicals. A challenge for science and technology is to gain a holistic understanding of the applicability domain and blind spots of cell platforms, as well as outcomes against which a positive in vitro call may be qualified. Advanced computer models and engineered microsystems will enable ‘recoding’ of cell-based data into the genomic blueprint of early development. This abstract does not necessarily reflect U.S. EPA policy. 

 

November 4, 2021 Speakers

 

Dr. C. Marc Luetjens, Ph.D. 

Senior Study Director, Labcorp

Title: Consequences of ICH guidelines on DART and JAS toxicity studies in primates 

Covance Preclinical Services GmbH Münster, Germany 

Over the last 25 years, the preclinical toxicity test based on the ICH guidelines has developed significantly. New and revised international guidelines have been published during this time. These innovations and changes fundamentally define the toxicity testing. With the dynamic development of new pharmaceutical groups, in particular biopharmaceuticals, the specialization of the test substances has increasingly concentrated on target markers that only occur in human patients. More and more of these substances do not have suitable binding sites in the classical animal models, which are used for pharmacological-toxicological investigations. Often, only the primates have target markers that are still similar enough to humans to be used as relevant animal species for the legally prescribed tests. Four ICH directives in particular are groundbreaking for the preclinical safety assessment of developing and reproductive medicinal products (DART) and paediatric use (JAS): [S5(R2) (1994&2005)] and [S5(R3) (2020)] for reproduction and fertility, [S6(R3) (1997&2011)] for reproduction and [S11 (2020)] for paediatric use. These guidelines provide the legal framework for the use of relevant animal models, in particular primates, in preclinical toxicity testing. In summary, it is shown here which primate species may and should be used in which biopharmaceuticals, or other new substance groups. As a result, we want to present our accumulated experience with primates from DART and JAS studies according to the above guidelines.

 

Donald G. Stump, Ph.D., D.A.B.T., A.T.S.

Principal Director of Toxicology, Midwest Region, Charles River Laboratories

Title: Nonclinical Fertility Assessment of Pharmaceuticals

Since FDA first published regulatory guidelines for reproductive studies for safety assessment of drugs for human use, fertility studies of pharmaceuticals in rodents have been routinely conducted.  These designs were focused on small molecules.  With the development of biologics, vaccines, and cell and gene therapy products, fertility testing has had to evolve.  This presentation will review fertility study designs employed for small molecules, vaccines, and biologics.  In addition, considerations for fertility assessment of cell and gene therapy products will be discussed.

 

Alan Hoberman, Ph.D.

Executive Director, Global Developmental, Reproductive and Juvenile Toxicology

Title: Reproductive and Developmental Toxicology Testing:  Cell and Gene Therapy Products – what should we do? 

With the moving of cell and gene therapy products to the clinic, the issues of safety to both the patient and subsequent generations produced by the patient needs to be addressed in both the theoretical and practical.  The basic safety question for subsequent generations is “Are the products of these therapies transmitted to the next generation through changes or editing of gametes or are only somatic cells affected.  For cellular products there has been little concern as most of these cells do not survive and cannot be passed to subsequent generations.  Gene therapies that do not involve changes in DNA should also be of minimal concern, However, gene therapies that involve editing in vivo and do have the theoretical potential to edit germ cells as well as somatic cells.  This presentation will review the current thinking and present some practical approaches for non-clinical safety testing for evaluation of germline transmission and/or editing of gametes.   

 

Adrian Tomkinson, Ph.D.

Senior Director, Nonclinical Safety and Pathobiology, Gilead Sciences

Title: Endochondral Ossification in Developing Long Bones of F1 Offspring Following Administration of Andecaliximab to F0 Dams During Gestation and Lactation

 Matrix metalloproteinase 9 (MMP9) has been shown to be related to trabecular bone architecture. In a pre/post-natal development study, F0 dams were administered an anti-MMP9 antibody andecaliximab (andeca) every 3 days IV at 10, 30 or 100 mg/kg/dose or vehicle GD 6 through LD 20. Skeletal bone radiographs, bone length, bone densitometry (pQCT), and histopathology of selected bones were assessed in F1 offspring on Days 21, 49, and 105 pp. Andeca F0 serum and milk conc. increased with increasing dose (milk 10- 20% of serum conc.).  F1 serum exposure increased with dose, and F1:F0 serum ratios ranged from 2 % at 10 mg/kg/dose to 60 % at 100 mg/kg/dose on LD 11, and were < 1% by LD 21. F1 survival, clinical condition, body weight and behavioral and reproductive function were unaffected. At 100 mg/kg/dose, animals presented persistent slight (£ 9%) decreases in femur length.  At Day 21 pp, these findings were associated with widespread changes in long bone physis, including increased thickness, metaphysis enlargement and/or increased radiographic bone correlating microscopically with physeal hypertrophy and increased trabecular metaphyseal bone, which were consistent with mild increases in metaphysis bone mineral content and density.  Radiographic and microscopic changes observed at Day 21 pp in long bone epiphysis and metaphysis were fully resolved by Day 49 pp. Bone densitometry changes at Day 49 pp consisted of increased total area at the femur distal metaphysis, associated with increased bone mass persisting to Day 105 pp and radiographic enlargement of the femur distal metaphysis. Additional findings at Day 105 pp included a few bent radii (varus), and radiographic bone loss in the proximal humerus occasionally associated with a luxation and/or osteophytes and/or enlargement of the proximal epiphysis. These results indicate F1 andeca exposure when administered to F0 dams during gestation and lactation and support the pharmacologic role of MMP9 in endochondral ossification of developing long bones.

About the Speakers

Jamie DeWitt, PhD, DABT

Professor, Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC.

Dr. Jamie DeWitt is Professor in the Department of Pharmacology and Toxicology of the Brody School of Medicine at East Carolina University in Greenville, North Carolina. She has B.S. degrees in Environmental Science and Biology from Michigan State University and Ph.D. degrees in Environmental Science and Neural Science from Indiana University-Bloomington. She completed postdoctoral training in ecotoxicology at Indiana University-Bloomington and in immunotoxicology at the U.S. Environmental Protection Agency in partnership with the University of North Carolina at Chapel Hill and joined ECU in 2008. Her laboratory’s research program explores relationships between biological organisms and their responses after exposure to environmental contaminants with a specific focus on the immune system and its interactions with the nervous system during development and adulthood. A particular focus of the research program is on emerging aquatic contaminants, especially per- and polyflouroalkyl substances (PFAS). She is active in the Society of Toxicology and the Society of Environmental Toxicology and Chemistry, serves as an Associate Editor for Toxicology and Applied Pharmacology and on the editorial boards of several other toxicological journals, and currently is funded to study the immunotoxicity and developmental immunotoxicity of PFAS as well as the microglial response in Gulf War Illness.

 

Sid Hunter II, Ph.D.

Chief of the Advanced Experimental Toxicology Models Branch, Biomolecular and Computational Toxicology Division, Center for Computational Toxicology in the Office of Research and Development in the U.S. Environmental Protection Agency (EPA)

Dr. Sid Hunter is Chief of the Advanced Experimental Toxicology Models Branch, Biomolecular and Computational Toxicology Division, Center for Computational Toxicology in the Office of Research and Development in the U.S. Environmental Protection Agency (EPA).  Dr. Hunter earned a B.S. in Chemistry, and M.S. in Toxicology. His Ph.D. is in Anatomy and Embryology from the University of North Carolina-Chapel Hill. He joined the Reproductive Toxicology Division at the US EPA in 1993 as a Research Toxicologist.  He presently holds an appointment of Faculty Affiliate at UNC-CH in the Toxicology Curriculum.

Dr. Hunter’s research interests and activities have focused on understanding the mechanisms responsible for chemically-induced developmental toxicity. He has used a variety of in vitro approaches, such as the whole embryo culture technique to study early craniofacial development, an adherent mouse embryonic stem cell culture model to evaluate the effects of ToxCast compounds and works to establish organotypic and microphysiological system culture models to evaluate chemical effects on developmentally critical targets. As part of the EPA’s Virtual Tissues Models research area, the Hunter lab contributes to the creation of predictive models of chemical effects on human development.

 

Aileen F. Keating, Ph.D.

Associate Professor, Department of Animal Science, Iowa State University

Dr. Keating is a Professor in the Department of Animal Science at Iowa State University. She received her doctorate in Biochemistry from the National University of Ireland, Galway in 2003 and was a postdoctoral fellow at the University of Alberta from 2004–2006, and the University of Arizona from 2006–2010. She is author or co-author of 85 peer-reviewed articles and nine book chapters. She serves on the board of directors for the Society for the Study of Reproduction and has served from 2016-2021 as the vice-president elect to past-president of the Society of Toxicology Reproductive and Developmental Toxicology Specialty Section. Her research investigates: 1) mechanisms by which ovotoxicants compromise ovarian function; 2) ovarian protective responses to ovotoxic xenobiotic exposures; and 3) ovarian biotransformation processes that contribute to ovotoxicity. Her ultimate aim is to minimize female reproductive dysfunction that is a consequence of ovotoxic chemical exposures. 

 

Thomas B. Knudsen, Ph.D.

Developmental Systems Biologist, Computational Toxicology and Bioinformatics Branch, Biomolecular and Computational Toxicology Division, Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency

Tom Knudsen is a Developmental Systems Biologist at the USEPA Center for Computational Toxicology and Exposure, where he leads research on computational models for predictive developmental toxicology. Prior to joining the EPA in 2007 he was Professor at the University of Louisville. His research on developmental processes and toxicities has resulted in over 160 publications and reviews focusing on mechanistic pathways. Dr. Knudsen served as a Past-President of the Society for Birth Defects Research and Prevention (formerly the Teratology Society) and Editor-in-Chief of Reproductive Toxicology (2003-19); he currently serves as Editor-in-Chief of ‘Toxicology’ and ‘Current Research in Toxicology’.

 

Dr. C. Marc Luetjens, Ph.D. 

Senior Study Director, Labcorp

 

 Dr. C.Marc Luetjens holds a PhD in biology and zoology with special expertise on early developmental. He specialized in male monkey physiology and comparative primate spermatogenesis at the primate center in Oregon USA and at the University of Muenster, Germany. His main topic as a Senior Study director includes general primate toxicology and development, reproductive and juvenile toxicology. He has been appointed as Global NHP DART Smart Matter Expert for Labcorp since 2020and looks after all NHP DART performed globally at Labcorp. As a member of a scientific society he actively has contributed to more than 80 publications including original contributions, book chapters and reviews, book editorship and acts as reviewer for scientific journals.

 

Donald G. Stump, Ph.D., D.A.B.T., A.T.S.

Principal Director of Toxicology, Midwest Region, Charles River Laboratories

Donald Stump is Principal Director of Toxicology, Midwest Region for Charles River Laboratories.  In this role he is responsible for the scientific conduct of the General Toxicology, Developmental and Reproductive Toxicology, Safety Pharmacology departments at the Ashland, Mattawan, Spencerville, Cleveland, and Skokie sites.  He offers toxicology consulting in the design of various development programs, while teaming up with business development colleagues to provide scientific representation. He serves as Study Director on DART and General Toxicology studies on a limited basis.

Dr. Stump received a Ph.D. in Biochemistry from Vanderbilt University and post-doctoral training at the National Institutes of Health.  Dr. Stump has published over 80 research articles and book chapters.  He has also made several presentations at regional and national meetings including meetings hosted by the American College of Toxicology, Society of Toxicology, Teratology Society, Korean Society of Nonclinical Study and the North American Congress of Clinical Toxicology.  He is currently an Associate Editor for the International Journal of Toxicology and is on the editorial board for both Birth Defects Research and Congenital Anomalies and has previously served on the editorial board of Reproductive Toxicology.  In addition, he has served on the NTP Board of Scientific Counselors and on the governing board of the American Board of Toxicology.  Dr. Stump is also a Fellow of the Academy of Toxicological Sciences.

 

Alan Hoberman, Ph.D.

Executive Director, Global Developmental, Reproductive and Juvenile Toxicology

Dr. Hoberman has been employed by Charles River Laboratories, Preclinical Services, Pennsylvania (formerly Argus Research Laboratories, Inc.) since 1981. He is a Diplomat of the American Board of Toxicology and a Fellow of the Academy of Toxicological Sciences, with over 85 publications and book chapters.  He is the co-editor of “Pediatric Non-Clinical Drug Testing, Principles, Requirements, and Practices” published in January 2012.

Dr. Hoberman has been a member of Birth Defects Research and Prevention since 1978 and is a Past President.  He is also a member of the European Teratology Society since 1982 and  councilor. He has been a member of the American College of Toxicology since 1979 and is currently the Vice President. He is a Past President of the Reproductive and Developmental Toxicity Specialty Section of the Society of Toxicology, the Middle Atlantic Reproductive and Teratology Association, and the Arkansas Biotechnology Organization.   

 

Adrian Tomkinson, Ph.D.

Senior Director, Nonclinical Safety and Pathobiology, Gilead Sciences

Dr. Adrian Tomkinson is a Senior Director in Nonclinical Safety and Pathobiology at Gilead Sciences, Inc. Adrian is an accomplished scientist with over 30 years of experience in academia, and preclinical drug development of both small molecule and biological therapeutics with start-up and large pharmaceutical companies, with particular expertise in inhalation drug delivery. He is highly skilled in leading development programs from discovery, through candidate selection, and into late-stage preclinical development. Following completion of a degree in pharmacology in 1987, and PhD in respiratory pharmacology in 1992, Adrian joined the Asthma Research Group at Rhone-Poulenc Rorer designing, developing novel in vivo models and in vitro assay systems to support small molecule drug development for several respiratory targets. Subsequently, he joined the lab of Dr Erwin Gelfand at National Jewish Medical Research Center, Denver CO in 1996, where research focused on the role of the T cell, Th2 cytokines and the impact of these on airways eosinophilic inflammation and airway hyperresponsiveness, before joining Bayer Healthcare, Berkeley CA in 2000. At Bayer, Adrian focused on the development of inhaled protein therapeutics for respiratory diseases. In 2004, Adrian was part of the successful spin out of the privately held company Aerovance from Bayer and was responsible for leading the pharmacology and inhalation toxicology programs to support the clinical development programs. In 2011, Adrian took up his current position at Gilead with responsibility for non-clinical safety and toxicology to support exploratory and development programs, both small molecule and biologics. Adrian is a committee member of the Association of Inhalation Toxicologists.