Immune Response to Vaccine Depends on Age by Angela Mohan on July 22, 2021 at 7:55 AM Elders found to have fewer antibodies against the novel coronavirus, as per the new study by research team from the Oregon Health & Science University. Antibodies are blood proteins that are made by the immune system to protect against infection. They are known to be key players in protection against SARS-CoV-2 infection. The study published in the Journal of the American Medical Association. "Our older populations are potentially more susceptible to the variants even if they are vaccinated," said senior author Fikadu Tafesse, Ph.D., assistant professor of molecular microbiology and immunology in the OHSU School of Medicine.