Program Director, Senior Staff Pathologist
Phone: (870) 543-7404
Dr. Malhi earned a Bachelor of Veterinary Medicine and a Master of Veterinary Medicine degree from the Punjab Agricultural University, India. After a stint in veterinary practice, he obtained a faculty position at the Punjab Agricultural University, India, where he taught undergraduate veterinary students and conducted research for the next five years.
Dr. Malhi immigrated to Canada in 2002 and was accepted into the PhD program in the Department of Veterinary Biomedical Sciences, University of Saskatchewan, Canada. During the PhD program, he investigated mechanisms of reproductive aging in cattle, as a model to elucidate age-associated infertility in women. During this period, he also obtained his veterinary license by successfully completing the North-American veterinary licensing examinations for foreign veterinary graduates.
After completing graduate studies, Dr. Malhi joined the Canadian Food Inspection Agency as a Veterinarian. Later, he was accepted into the residency program in veterinary anatomic pathology at the Kansas State University. Upon completion of the residency program, Dr. Malhi set for and successfully completed the certification examination of the American College of Veterinary Pathologists in the year 2012.
Dr. Malhi returned to Canada and worked as a Veterinary Diagnostic Pathologist in a high-throughput state diagnostic laboratory for few years before accepting a Toxicologic Pathologist position with Citoxlab, a Charles River Company. While at Citoxlab, he served as a study pathologist for a variety of general toxicologic, reproductive and radiation studies in a variety of rodent and non-rodent species.
In 2019, Dr. Malhi was recruited by Toxicologic Pathology Associates, Inc. (TPA) and is currently serving with the TPA team as the Program Director and Senior Staff Pathologist in support of the research community at the Food and Drug Administration’s (FDA’s) National Center for Toxicological Research (NCTR). Dr. Malhi is also an Adjunct Professor in the Department of Veterinary Pathology at the University of Saskatchewan, Canada.
Senior Staff Pathologist
Phone: (870) 543-7265
Dr. Hanks is a veterinary pathologist who has maintained great interest in the pursuits of research since the early days of her career. She has dedicated her career to the forwarding of safe application of pharmaceuticals and new technologies for medical practice and scientific advancement. Her expertise has been developed over a range of companion animal diagnostics, NIH and DHS-funded infectious disease research, and toxicological investigation involving numerous rodent and non-rodent animal models of disease.
Dr. Hanks earned her veterinary and master’s degrees from Mississippi State University in 2006, with a focus on Department of Homeland Security-funded research in vesicular stomatitis virus, toxicology, and parasitic animal disease in marine mammals. She went on to complete a residency in veterinary pathology at the University of Missouri – Columbia, with board certification as a Diplomate of the American College of Veterinary Pathologists in 2011. After completing post-doctoral research funded by a National Institutes of Health K08 grant for a rodent model of Lyme disease arthritis and vaccination in 2012, she founded an independent consulting business, MicroCorps Pathology Services. Her primary contracts included Sinclair Research Center, a contract research group (Columbia, MO), and IDEXX BioAnalytics, an international provider of veterinary laboratory clinical diagnostics and services (Westbrook, ME). As a consultant, Dr. Hanks participated in a wide variety of preclinical and clinical animal models of pharmacologic research, including gross and histological responsibilities, with a focus on drug discovery, device, wound healing, toxicology, and safety studies in both Good Laboratory Practices (GLP) and non-GLP settings.
Dr. Hanks was pleased to join the TPA team as a Senior Staff Pathologist in 2021 and endeavors to work closely with study directors to develop new models of disease and facilitate development of the Food and Drug Administration's (FDA) knowledge base for biological, chemical, and pharmaceutical safety for veterinary and human use at the National Center for Toxicological Research (NCTR) in Jefferson, Arkansas.
Dr. Hanks is a member of the American College of Veterinary Pathologists, Society of Toxicologic Pathology, and Davis-Thompson Foundation.
Senior Staff Pathologist
Phone: (870) 543-7077
Dr. Witt earned his D.V.M. degree from Texas A&M University where he became a U.S. Air Force - sponsored veterinary student during his final year of veterinary college. Upon graduation Dr. Witt was assigned to Biodynamics Branch of the United States Air Force School of Aerospace Medicine (USAFSAM) where he was active in acceleration research. Following his three-year tour Dr. Witt was selected by the Air Force for graduate training in veterinary pathology which was completed in 1983 by earning his Ph.D. degree at Texas A&M University.
As a veterinary pathologist, Dr. Witt was assigned to the Veterinary Pathology Branch, Veterinary Sciences Division, USAFSAM, where he served as Director of the Clinical Pathology Laboratory and as a staff pathologist. In 1987, Dr. Witt applied for and received an inter service transfer from the U.S. Air Force to the U.S. Public Health Service with assignment to the National Center for Toxicological Research (NCTR) in Jefferson, Arkansas.
After arriving at the NCTR, Dr. Witt was named Director, Division of Veterinary Services where he was a member of NCTR’s management team consisting of top level management, administrative and scientific officers responsible for the research program at the Center. He was responsible for continued AAALAC accreditation of NCTR’s animal care and use program. Dr. Witt also served as Project Officer for the Pathology Services Contract, interacting with the contractor’s management personnel to prioritize projects thereby ensuring that the user’s needs and timelines were fulfilled in a satisfactory manner and to ensure that the technical aspects of the contract were fulfilled by the contractor as part of NCTR's contract-specific planning and the overall annual NCTR budget process.
Dr. Witt was recruited away from the NCTR in 2004 for the position of Director, Animal Resources Center (ARC), the University of Texas Medical Branch (UTMB) located in Galveston, Texas. As Director, Dr. Witt managed or directed all activities of and supervised, or oversaw the supervision of, all personnel tasked with providing and maintaining quality laboratory animals in support of the UTMB Research Community. Dr. Witt provided advice, technical direction, developed SOPs and oversaw the ARC’s Good Laboratory Practices (GLP) activities in support of the UTMB Research Community.
Dr. Witt returned to NCTR in November 2006 as TPA’s General Manager and as a Senior Staff Pathologist. Dr. Witt became TPA's President in 2008 and also served as Program Director from 2008 until 2019. Dr. Witt will continue to serve as a senior staff pathologist for TPA at NCTR.
Senior Staff Pathologist
Phone: (919) 482-3422
For the past 18 years, Dr. Olson has been an essential member of the pathology team at the NCTR, quickly gaining respect from his contractor and NCTR client colleagues. Dr. Olson has made vital contributions to PAI since joining as a pathologist/program manager in February of 1985. He earned his Ph.D. in Veterinary Pathology from Iowa State University and his M.S. and D.V.M. from Michigan State University. Prior to earning his Ph.D., he managed a successful private veterinary practice.
From 1985–2001, Dr. Olson supported EPA-sponsored environmental research programs. He served as a Managing Scientist, Principal Pathologist, Project Manager and Program Manager on 10 separate EPA contracts with a combined value of more than $35 million.
Dr. Olson joined the PAI/NCTR staff in January 2001 as a senior staff pathologist. He is responsible for applied research in the toxicologic pathology of drugs and food-borne chemicals, especially histopathological analysis of tissues from subchronic and chronic rodent carcinogenicity bioassays. He has participated as the study pathologist on the following bioassays: Genistein: Evaluation of Reproductive Effects over Multiple Generations and the Chronic Effect of Exposure during Various Stages of Life, Ethinyl Estradiol: Evaluation of Reproductive Effects over Multiple Generations and the Chronic Effect of Exposure during Various Stages of Life, Phototoxicity of Retinyl Palmitate, Genistein in the Rat Mammary Gland Model, HIV Drug Combination, Tattoo Pigment Phototoxicity, Caloric Restriction in the F-344 Rat, Oral Aloe Vera, Acrylamide, Glycidamide, Usnic Acid, Usnea Barbata, Usnea Lichen, BPA, Triclosan, Furan, Melamine, Nanosilver and Oxybenzone, Glucosamine, Chondroitin, Brominated Vegetable Oil, Aspirin, Lumbrokinase, and Nattokinase.
Dr. Olson’s pathology and collaborative research efforts at the NCTR have been very well received by the NCTR’s investigative community. He has been a participant in numerous PWG’s and Technical Report reviews. His exceptionally strong toxicologic pathology experience as well as his understanding and appreciation for the efficiencies provided by technologic innovation are ideal for his position at the NCTR.
Senior Staff Pathologist
Phone: (870) 543-7689
Dr. Davis earned his D.V.M. from Auburn University. After seven years of successful private practice, Dr. Davis joined the U.S. Army Veterinary Corps and from 1983-1988 was assigned to Ft. Bragg, North Carolina and Naval Station, Guam as a Veterinary Officer prior to becoming eligible for a residency training program.
From 1988-1991, Dr. Davis was a veterinary pathology resident at the Armed Forces Institute of Pathology. Dr. Davis successfully completed the certifying examination of the American College of Veterinary Pathologists (ACVP) and became a Diplomate, American College of Veterinary Pathologists (DACVP).
From 1991-1996, Dr. Davis was assigned to the Pathology Division of the U.S. Army Medical Research Institute of Infectious Diseases where he served as Chief of the Department of Immunohistochemistry and later as Chief of the Experimental Pathology Branch. As Chief of Immunohistochemistry, he directed a laboratory that developed new immunocytochemical assays for cell markers, infectious disease agents and toxins and provided routine immunohistochemistry support to numerous research protocols.
From 1996-1998, Dr. Davis was assigned to the Medical Research and Materiel Command where he served as the Program Director for the Medical Biological Defense Research Program.
From 1998-1999, Dr. Davis was assigned as Commander of the 248th Medical Detachment where he served a successful battalion-level command tour. The rapidly deployable medical unit had six veterinary teams assigned to five Department of Defense installations.
From 1999-2003, Dr. Davis was assigned back to the U.S. Army Medical Research Institute of Infectious Diseases where he served as Chief of the Pathology Division and later as the Deputy Commander of the Institute.
From 2003-2009, following his retirement from military service, Dr. Davis served as a Senior Staff Pathologist and Project Manager and later as a Division Director for Pathology Associates at Charles River Laboratories, Redfield, Arkansas.
Dr. Davis joined the TPA/NCTR staff as a senior staff pathologist in July 2009 and served as Director of Laboratory Operations from 2013 to 2019.
Methods Development Manager, IHC and Molecular Pathology Laboratory
Phone: (870) 543-7294
Dr. Muskhelishvili graduated from Tbilisi State University, Republic of Georgia, in 1973. He earned his Ph.D. degree in histology and embryology from N.K. Koltsov Institute of Developmental Biology, Moscow, Russia in 1979, and his Doctor of Science degree in cancer research from R.E. Kavetsky Institute of Oncology Problems, Kiev, Ukraine, in 1991.
Professionally, Dr. Muskhelishvili has 45+ years of experience conducting research on human medical and physiologic questions using animal models. From 1973 to 1985, he worked at the Institute of Pharmacochemistry of Georgian Academy of Sciences as a research scientist. In 1985 he joined the Laboratory of Pathology at Georgian Cancer Research Center as a senior research scientist. From 1988 to 1993, he directed the Cytological Laboratory at the Center. From October 1993 to December 1996, he worked in the NCTR’s Division of Nutritional Toxicology as a visiting scientist; projects included “The immunotoxicity and carcinogenicity of silicone breast implants” and “Project of calorie restriction”.
Dr. Muskhelishvili joined the TPA staff as an immunohistochemist in January 1997. Since September 2003, he has managed the newly organized molecular pathology laboratory. His primary role is to assist NCTR investigators by applying methods of immunohistochemistry and molecular pathology to identify, locate and quantify target molecules of interest in cells and tissues. He also adapts available methods to new applications and development of novel methods. Since joining TPA, he developed more than 180 immunohistochemistry protocols, introduced to the laboratory apoptosis assays—TUNEL and ISOL—and several in situ hybridization protocols. All these techniques are in use at TPA, serving NCTR investigators.
Research Associate, IHC and Molecular Pathology Laboratory
Phone: (870) 543-7026
Dr. Elkins earned her M.S. degree from Arkansas State University (ASU) in 2012 working on production of a protein subunit vaccine against flu. She continued her education at ASU where she earned her Ph.D. degree in molecular biosciences in 2019 researching the production of a therapeutic protein for mitigating disease in aquaculture catfish. She continued work at ASU in a post-doctoral teaching position in the Department of Biology where she also researched the enhanced delivery of fish therapeutics.
In 2021, Dr. Elkins accepted a post-doctoral fellowship at St. Jude Children’s Research Hospital working with endoplasmic reticulum chaperones and their role in preventing protein aggregation. Near the end of her fellowship Dr. Elkins was recruited by TPA and officially joined the TPA Team in 2022 as a Research Associate whose primary role is using molecular pathology to assist FDA/NCTR investigators by identifying, locating, and quantifying target molecules of interest in a variety of cells and tissues, adapting methods for new applications and development of novel methods and procedures. Dr. Elkins brings to the TPA Team over 10 years of training and experience in molecular biology protein biochemistry and cell biology.
Manager, Clinical Services
Phone: (870) 543-7379
Before coming to NCTR, Mr. Patton had more than 31 years of experience in both the technical and operational aspects of the clinical laboratory. Prior experience included serving as operational manager of laboratory services for a national laboratory in Arkansas. His duties included supervising 60 employees at seven locations.
Mr. Patton joined our NCTR team in 1996 and has functioned as the manager and/or supervisor of the clinical chemistry/hematology laboratory since then. He is certified as a medical laboratory technician with the American Society of Clinical Pathology and as a medical technologist with the Department of Health, Education and Welfare. He is also a national member of the Clinical Laboratory Management Association and the American Association of Clinical Chemistry. He is skilled in all aspects of clinical chemistry and hematology for multiple species and has an excellent understanding of GLPs and clinical quality assurance (QA) and quality control (QC) programs.
Since joining the staff at NCTR, Mr. Patton’s management skills have increased the efficiency and productivity of the laboratory. Mr. Patton has developed new methods to assist the PIs with their studies, working closely with the PIs at the NCTR.
Research Services Manager
Mr. Warbritton is a registered histotechnician with 50 years of experience in various aspects of histologic technique and special procedures. He has developed considerable expertise in immunohistochemical procedures and morphometric analysis, requests for which have increased considerably at the NCTR, and continued growth in these specialty areas is obvious. Given the great number of permutations possible in the factors affecting the methodology, Mr. Warbritton’s experience and leadership in immunohistochemistry (IHC) provide a major advantage to the NCTR. The image analysis system now overlaps with photography as a functional service area, and Mr. Warbritton is an acknowledged expert in both areas.
Mr. Warbritton’s expertise in digital pathology/image analysis has the potential to develop techniques and procedures that can quantify many current labor-intensive, time-consuming procedures such as measurement of microscopic structures in tissues. These procedures lend themselves to multiple applications in research collaborations and we see continued potential for TPA to enhance NCTR’s research capabilities in this area. Mr. Warbritton’s diligent application of his broad aptitudes during the past 46 years of service has endowed him with an impressive list of skills, abilities and accomplishments.
Phone: (870) 543-7035
Ms. Raiford is a 45+ year veteran of the NCTR and a highly respected member of our organization. She is an ASCP-certified histology technician. She has served in roles of increasing responsibility as a necropsy and histology technician, research technologist, NCTR-qualified pathologist assistant, and operations manager for the technical support area.
In the role of Program Manager, she coordinates all recruitment, new hires, terminations, and disciplinary actions. She works with the Program Director, laboratory managers, NCTR division directors and principle investigators to identify personnel requirements. She plans and develops protocol budget requirements within limits of the contract.
Ms. Raiford’s thorough grounding in the technical areas is essential in costing protocols. Her contacts with the NCTR scientific community during her former role as operations manager have earned the confidence and respect of all members of that group. Ms. Raiford’s experience and dedication, her personal standard of excellence, popular leadership, and her high regard from the NCTR, government, and other contractor personnel make her an invaluable team member. Her mastery of the many facets of her job, her positive commitment to the welfare of the employees, and her prodigious capacity for work make her a source of confidence and pride among the staff.
Ms. Raiford’s overall responsibility is to manage all administrative and technical aspects of the contract, marshalling the technical resources to deliver the materials and reports the pathologists require in their evaluations of the studies.
Phone: (870) 543-7402
Ms. Vilches is responsible for coordinating the full complement of administrative activities of the pathology contract. Her specific experience for the contract includes payroll and benefits; all budgetary functions, from proposal preparation to monthly billing; overseeing travel arrangements for professional and technical staff; overseeing monthly charges for labor; contract administration between TPA and the NCTR Federal COs; coordination of monthly, quarterly, semiannual and annual financial reports; IAG/NCTR cost recovery system; identifying and tracking cost on a monthly basis for all experiments supported by pathology; and deliverables (such as reports) as indicated in the contract. Ms. Vilches routinely interacts with the NCTR contracts staff, the NCTR planning staff, the NCTR/NTP liaison staff and the NCTR Federal Contract Offices to provide accurate information needed for tracking and billing of labor and materials and supplies.
Ms. Vilches’ invaluable experience, outgoing personality, industriousness and commitment to excellence are second to none. Her rapport with NCTRs contract administration personnel has been a strong positive factor in the harmonious working relationship we have enjoyed with that group over the past 35+ years.
Quality Assurance Manager
Phone: (870) 543-7716
As Quality Assurance Manager, Ms. Wiley provides the TPA team with quality assurance and GLP-compliance-related services that have been repeatedly applauded by our NCTR clients and representatives from other organizations. Ms. Wiley is skilled in quality assurance management with an understanding of compliance requirements for all aspects of toxicology studies.
With 45+ years of experience in biomedical services gained in the Pathology Division at the NCTR, Ms. Wiley has extensive experience in rodent toxicology, computerized pathology data systems and quality control practices with quality assurance oversight in a GLP laboratory. During her tenure with our NCTR team Ms. Wiley has held multiple positions in the Pathology laboratory including necropsy technician and histology technician (HT/ASCP certified). Other positions she has held include research technologist, pathologist assistant, Data Administrator and Quality Assurance Specialist leading into her current role of Quality Assurance Manager.
As Quality Assurance Manager for TPA, Ms. Wiley is responsible for planning, auditing and reporting Quality Assurance activities to ensure compliance with FDA and EPA regulations and OECD guidelines, standard operating procedures and TPA company policies. Ms. Wiley is charged with monitoring and verifying the accuracy and completeness of data produced and collected by TPA personnel and provides quality assurance oversight for all aspects of TPA services. With 30+ years of specialized experience in Quality Assurance, Ms. Wiley also provides GLP training to all TPA personnel as well as interpretation and guidance for all regulatory matters to the TPA team. In addition to providing these services to TPA, Ms. Wiley is an experienced trainer for the FDA Advanced Non-Clinical Bioresearch Monitoring Program and has conducted numerous training courses by invitation. She has also presented multiple training classes in GLP for the National Society of Histotechnology by invitation.
Phone: (239) 248-4592
Dr. Knutsen, TPA’s Chairman and CEO, is a veterinary toxicologic pathologist who has been establishing, operating and investing in contract research discovery and preclinical pathology companies for nearly four decades. In 1981, he founded Pathology Associates International (PAI), a company that over two decades grew into the largest contract toxicologic pathology specialty organization in the world prior to its sale to Charles River Laboratories in 2001. In 2004 when a unique FDA-sponsored small business contract research opportunity became available, Knutsen helped a number of his former colleagues at PAI establish TPA, an entity that for the past 14 years has provided high profile toxicologic pathology research services in support of FDA’s distinguished National Center for Toxicological Research (NCTR), Jefferson, Arkansas. In 2006, Knutsen founded Systems Pathology Company, a Seattle-based artificial intelligence digital pathology imaging company that closely collaborated with both TPA and the FDA/NCTR before Charles River Laboratories purchased the company in 2009. A graduate of Cornell College (BA, 1969) with graduate degrees from Iowa State University in veterinary medicine (DVM, 1975) and physiology (MS, 1975), Knutsen received his pathology residency training while an officer in the United States Army, serving for six years as a member of the research team at the Army’s infectious disease research center (USAMRIID) at Fort Detrick, Maryland.
Chief Financial Officer and Contracts Manager
Phone: (301) 471-0069
Bill has over 35 years of accounting, financial management and government contracting experience. After earning his bachelor’s degree from Frostburg State University in June of 1986 and passing the CPA exam in November 1986, he spent 8 years working for a public accounting firm where he specialized in government contract accounting, auditing and tax compliance. In 1994 Bill joined Pathology Associates where he worked for over 10 years serving as the Chief Financial Officer until the sale of the company in 2001. Thereafter, he continued to serve in numerous financial and general business management roles including General Manager of the Pathology Associates Division. Bill has been involved with Toxicologic Pathology Associates (TPA) since its inception, assisting with the formation of the company and establishing the accounting policies and procedures. In addition to directing the accounting and financial reporting compliance, he has overall responsibility for the financial and contract management of TPA.