In an Oct. 12 briefing on Capitol Hill, U.S. congressional staff learned more about the growing scientific consensus that many autoimmune diseases likely result from interactions between genetic and environmental factors. The Friends of NIEHS organized the meeting, along with the American Autoimmune Related Diseases Association, the American Thoracic Society, and the Endocrine Society.
U.S. Senator Richard Burr from North Carolina, where NIEHS is located, was the honorary host. Attendees included staff from his office and the offices of senators and representatives from 10 other states, as well as groups such as the Society for the Psychological Study of Social Issues, Research!America, and the National Center for Health Research.
Growing evidence for role of environment
“There are over 80 different acquired disorders that fall into the category of autoimmunity and more than 24 million Americans are affected, according to the NIH [National Institutes of Health] Autoimmune Disease Coordinating Committee,” said NIEHS Deputy Director Rick Woychik, Ph.D., who presented an overview.
“There is a growing body of literature that says the environment is probably playing a major role in the development of autoimmune disease,” said NIEHS lead researcher Frederick Miller, M.D., Ph.D., who leads the NIEHS Environmental Autoimmunity Group. He said researchers suspect a link with exposures for several reasons.
- The frequency of autoimmune disease is increasing faster than the speed at which genes evolve and change, pointing to a nongenetic factor.
- Sometimes only one identical twin is affected with autoimmune disease.
- Environmental factors lead to autoimmunity in laboratory studies.
- Epidemiological studies also link environmental exposures and autoimmune diseases.
PFAS, cadmium highlighted
The other presenters were Dori Germolec, Ph.D., from the National Toxicology Program (NTP), which is based at NIEHS, and NIEHS grantee John Barnett, Ph.D., from West Virginia University.
Germolec discussed a class of persistent chemicals known as per- and polyfluoroalkyl substances (PFAS), stating that there is a consistent pattern of findings on the immune effects of these compounds. PFAS are widely used in stain-resistant fabric coatings, firefighting foams, lubricants, and food packaging.
“Epidemiological studies have found increased asthma in children, reduced antibody response to vaccines, and increased incidence of ulcerative colitis,” she said, referring to the specific PFAS compounds known as PFOA and PFOS.
Barnett studies effects of exposure to cadmium, a naturally occurring element that is used in batteries, metal alloys, solar cells, and in plastics and pottery. Exposures also occur from tobacco smoke and certain grains.
His lab is one of the few in the world looking at how exposure to heavy metals in the womb predisposes offspring to autoimmune diseases. “Prenatal cadmium exposure reduces normal levels of immune regulatory cells, which causes an abnormal increase in antibody production, potentially leading to autoimmune disease,” Barnett told the audience.
Discussion adds to understanding
Questions for the panelists related to community concerns, such as ambient exposures versus occupational exposures, and specific diseases. Interagency collaboration and NIEHS Strategic Plan priorities for research funding were also of interest.
Panelists suggested that future research target genetic risk factors, mechanisms behind effects, and subgrouping of autoimmune diseases for studying how they relate to risk factors.
At NTP, studies to clarify relevant exposure levels and mechanisms by which PFAS influence autoimmunity will be launched in 2018, building on the 2016 NTP monograph on PFOA and PFOS immunotoxicity.
The Friends of NIEHS sponsors and organizes one to two congressional briefings each year to facilitate the exchange of information between scientists and congressional staff, and build appreciation for environmental health. Friends co-chair Joe Laakso, Ph.D., from the Endocrine Society, was the lead organizer of this meeting.
(Jed Bullock is the NIEHS legislative liaison.)