Scientists at the Michigan State University have linked a common food preservative with a changed immune response that is likely to interfere with the flu vaccine.
A study on mice, presented at an experimental biology meeting in 2019 in Orlando, Florida, April 7 at 9 am, offers a new potential factor in the effectiveness of the vaccine.
Tert-butylhydroquinone, or tBHQ, can be found in several food products, including cooking oils, frozen meat (especially fish) and processed foods such as chips and crackers. Products do not necessarily have to be included in the list of ingredients.
"If you get a vaccine, but part of your immune system does not learn to recognize and fight against cells infected with a virus, it can cause a smaller vaccine," said Robert Freeborn, a fourth-year doctoral student. conducted a study with Cheryl Rockwell, an associate professor of pharmacology and toxicology. "We found that when tBHQ was introduced into the diet, it affected certain cells that are important for the proper immune response to the flu."
Using various strains of influenza, including H1N1 and H3N2, Freeborn and Rockwell focused on CD4 and CD8 T cells and incorporated tBHQ in mice food in an amount comparable to human consumption.
"CD4 T stations are like movie directors who tell everyone else what to do," said Freeborn. "CD8 T cells are actors that make up what the director wants."
Researchers have studied several response factors, including whether T-cells emerged, were able to do a real job, and eventually identify and remember the attack virus.
"Overall, we saw a reduced number of CD8 T cells in the lungs and a decrease in the number of CD4 and CD8 T cells that could identify the influenza virus in mice exposed to tBHQ," Freeborn said. "These mice also had widespread inflammation and mucus production in the lungs."
TBHQ also slowed down initial T cell activation, reducing their ability to fight infections faster. This allowed the virus to break into the mice until the cells were fully activated.
The second phase of the study showed that the additive prevented the ability of the immune system to remember how to respond to a flu virus, especially when another form was introduced at some other time. This resulted in longer recovery and additional weight loss in mice.
"It's important for the body to recognize the virus and remember how to effectively fight it," said Freeborn. "It's the whole purpose of the vaccine, to trigger this memory and to create immunity. TBHQ seems to disturb this process."
The research was funded by the National Institute of Health.
Source: University of Michigan State