A genetic “crystal ball” can predict whether the flu vaccine will work well for certain people.
Nine genes are tied to a strong immune response to the flu vaccine in people 35 and under, a new study finds. If these genes are highly active before vaccination, a person will respond to the flu shot by making lots of antibodies. This is true no matter what flu variety, or strain, is in the vaccine. The response can help a person avoid getting the flu.
Getting a flu shot is the best way to stay healthy during flu season. The U.S. Centers for Disease Control and Prevention estimates that flu vaccines prevented 5.1 million illnesses in the 2015‒2016 season. “The problem is, we don’t know what makes a successful vaccination,” says Purvesh Khatri. He’s an immunologist at Stanford University School of Medicine in California. “The immune system is very personal,” he says.
Khatri and colleagues wondered if a person’s immune system needs to be in a certain state to respond well to the flu vaccine. So the researchers looked at blood samples from 175 people around the United States. They had different genetic backgrounds. They also had gotten the flu shot in different seasons. The scientists searched the blood samples for a common genetic signal. They found nine genes that were especially active in people 35 or under and whose blood showed a strong immune response to the flu vaccine.
After identifying these genes, the team used another 82 blood samples to double-check that the genes predicted a good response to the flu vaccine. Using a variety of samples makes it more likely that this crystal ball will work for many different people in the real world, Khatri says. The researchers reported their findings online August 25 in Science Immunology.
The nine genes make proteins that have various jobs. They do things like telling other proteins where to go and giving structure to cells. Earlier research has tied some of these genes to the immune system. Khatri thinks the new study will lead to more research into how these genes encourage a good vaccine response. And figuring out how to boost the genes may help people who don’t respond strongly to flu vaccines, he says.
The research team looked for a similar set of genes in people aged 60 and over. In older people, the flu is more likely to lead to serious complications, such as a lung disease known as pneumonia. But the scientists couldn’t find a set of genes in this group that predicted flu-vaccine responses.
Even so, the study is “a step in the right direction,” says Elias Haddad. He’s an immunologist at Drexel University College of Medicine in Philadelphia, Pa. He was not part of the new research. Maybe a simple test before a vaccination could help predict who will respond well to the flu shot, he says.
As for finding a genetic crystal ball for older adults, “there’s still hope that we’ll be able to,” says Raphael Gottardo. He’s a computational biologist at the Fred Hutchinson Cancer Research Center in Seattle, Wash. He worked on the new study. Older people have a wider range of responses to the flu vaccine than do younger people, he says. That means it may take a larger group of samples to find a genetic pattern.
It will also take more research to learn whether the nine genes predict a strong response for all vaccines, or just the flu shot, Haddad says. “There is a long way to go here.”
biology The study of living things. The scientists who study them are known as biologists.
cancer Any of more than 100 different diseases, each characterized by the rapid, uncontrolled growth of abnormal cells. The development and growth of cancers, also known as malignancies, can lead to tumors, pain and death.
cell The smallest structural and functional unit of an organism. Typically too small to see with the unaided eye, it consists of a watery fluid surrounded by a membrane or wall. Depending on their size, animals are made of anywhere from thousands to trillions of cells. Most organisms, such as yeasts, molds, bacteria and some algae, are composed of only one cell.
Centers for Disease Control and Prevention, or CDC An agency of the U.S. Department of Health and Human Services, CDC is charged with protecting public health and safety by working to control and prevent disease, injury and disabilities. It does this by investigating disease outbreaks, tracking exposures by Americans to infections and toxic chemicals, and regularly surveying diet and other habits among a representative cross-section of all Americans.
colleague Someone who works with another; a co-worker or team member.
crystal (adj. crystalline) A solid consisting of a symmetrical, ordered, three-dimensional arrangement of atoms or molecules. It’s the organized structure taken by most minerals. Apatite, for example, forms six-sided crystals. The mineral crystals that make up rock are usually too small to be seen with the unaided eye.
gene (adj. genetic) A segment of DNA that codes, or holds instructions, for a cell’s production of a protein. Offspring inherit genes from their parents. Genes influence how an organism looks and behaves.
genetic Having to do with chromosomes, DNA and the genes contained within DNA. The field of science dealing with these biological instructions is known as genetics. People who work in this field are geneticists.
immune (adj.) Having to do with the immunity. (v.) Able to ward off a particular infection. Alternatively, this term can be used to mean an organism shows no impacts from exposure to a particular poison or process. More generally, the term may signal that something cannot be hurt by a particular drug, disease or chemical.
immune system The collection of cells and their responses that help the body fight off infections and deal with foreign substances that may provoke allergies.
immunology The field of biomedicine that deals with the immune system. A doctor or scientist who works in that field is known as an immunologist.
influenza (also known as flu) A highly contagious viral infection of the respiratory passages causing fever and severe aching. It often occurs as an epidemic.
online (n.) On the internet. (adj.) A term for what can be found or accessed on the internet.
pneumonia A lung disease in which infection by a virus or bacterium causes inflammation and tissue damage. Sometimes the lungs fill with fluid or mucus. Symptoms include fever, chills, cough and trouble breathing.
protein A compound made from one or more long chains of amino acids. Proteins are an essential part of all living organisms. They form the basis of living cells, muscle and tissues; they also do the work inside of cells. Among the better-known, stand-alone proteins are the hemoglobin (in blood) and the antibodies (also in blood) that attempt to fight infections. Medicines frequently work by latching onto proteins.
strain (in biology) Organisms that belong to the same species that share some small but definable characteristics. For example, biologists breed certain strains of mice that may have a particular susceptibility to disease. Certain bacteria or viruses may develop one or more mutations that turn them into a strain that is immune to the ordinarily lethal effect of one or more drugs.
vaccine (v. vaccinate) A biological mixture that resembles a disease-causing agent. It is given to help the body create immunity to a particular disease. The injections used to administer most vaccines are known as vaccinations.
Journal: HIPC-CHI Signatures Project Team and HIPC-I Consortium. Multicohort analysis reveals baseline transcriptional predictors of influenza vaccination responses. Science Immunology. Published online August 25, 2017. doi:10.1126/sciimmunol.aal4656.