ANN ARBOR, Mich. (WOOD) — A new study led by researchers at the University of Michigan shows how genetics play a key role in how each person’s body reacts to booster shots.

The study was a partnership with the Australian National Health and Research Center and the American Foundation for AIDS Research. Unlike the original vaccine, boosters re-expose the immune system to a virus or some portion of it to boost the body’s natural immune response. Not every body reacts the same way. The booster doses increase the number of antibodies in a person’s system, but genetics dictate how well the immune receptors stick to those antibodies.

“Different people vary in the amount and type of antibodies they produce,” Kelly Arnold wrote in a 2021 study published in Cell Reports Medicine.

Arnold is an assistant professor of biomedical engineering at the University of Michigan and one of the leading researchers on the study.

“Depending on their genetics, they also have different protein sequences in their antibodies and immune cell receptors that cause them to bind differently,” Arnold said.

She says two people can have the same antibody count but have different immune responses and, theoretically, booster doses can be specifically designed to make them more effective for people depending on their genetic makeup.

That technology is not yet available, but it could be possible.

“Depending on your genetic background, we’ve found that vaccine boosting may be more or less effective in activating certain innate immune functions,” Arnold told the University of Michigan Health Lab. “And in some people, where boosting the concentrations of antibodies was ineffective, being able to change the affinity of antibodies could be the more successful route.”

Arnold and her research team have worked with their partners in Australia, Thailand and other places in the United States to create a computer model to determine how different genetic factors dictate immune responses.

Melissa Lemke, a Ph.D. candidate who led the 2021 study, says vaccine formulas developed for specific genetic traits is key in fighting viruses that mutate rapidly, like COVID-19, HIV or influenza.

“This means that in order to protect all people to the same degree from a variety of viral mutations, we need an array of possible solutions that can be matched to any given person’s health status, sex, age and genetic background,” Lemke told the University of Michigan Health Lab. “Computational tools like this one are going to be essential in speeding up the search for mechanisms that can be implemented to create effective vaccines for all.”