Emory University researchers report laboratory data on how the updated 2023–24 COVID vaccine might protect against current and future variants. The small study of 24 participants, published in Science and Translational Medicine, tracked immune durability, breadth, and magnitude over a six-month period. Key measures included memory B cells, binding antibodies that flag pathogens, and neutralizing antibodies that can block virus replication.
The 2023–24 vaccine was monovalent and matched the then-dominant Omicron XBB.1.5, whereas prior vaccines were bivalent and contained two spike proteins. Tests showed the vaccine induced antibodies with a half-life of more than 500 days; at least 50% of antibodies remained detectable more than 16 months after vaccination. Participants also made cross-reactive antibodies that recognized both the ancestral WA1 strain and XBB.1.5. The team reported that immune imprinting likely contributed to a 2.8-fold increase in these cross-reactive antibodies.
The study also highlights broader concerns: SARS-CoV-2 has produced more than 12,700 coronavirus mutations, five strains and nearly 4,00 variants, and infection can affect mitochondrial function and harm organs such as the heart, kidneys, liver, and lymph nodes. The researchers list groups at higher risk of severe disease, including people with cancer, blood and autoimmune disorders, stroke, obesity and pre-existing heart, kidney, lung or liver conditions. Coauthors were from Emory, the NIH, Stanford, and the CDC, and funding came from the National Institutes of Health, the National Institute of Biomedical Imaging and Bioengineering, and Emory funds.
- Suthar said the monovalent vaccine broadened protection.
- Updated vaccination boosts cross-reactive antibodies.
- Researchers call for continued research and updated immunizations.
Difficult words
- durability — how long protection or effect continues
- memory B cells — a white blood cell that remembers pathogens
- binding antibodies — an antibody that attaches to a pathogen
- neutralizing antibodies — an antibody that blocks virus replication
- monovalent — a vaccine containing one version of antigen
- bivalent — a vaccine containing two different antigen types
- cross-reactive antibodies — an antibody that recognizes different virus strains
- immune imprinting — prior immune response shaping later responses
- half-life — time for a quantity to reduce by half
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- What are possible advantages and disadvantages of a monovalent vaccine matched to a current variant like XBB.1.5?
- How might immune imprinting affect the long-term effectiveness of updated vaccines?
- Which groups from the article should be prioritized for updated immunizations, and why?
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