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The immune system fights disease

Each year flu season affects millions of Americans. With our immune systems at the center of the fight, protection comes from both past infection and vaccination.

Learn more about the flu season Learn more about the flu season

The immune system aids in recovery

A Harvard study suggests that exercise may be a natural way to boost the body’s immune responses to reduce inflammation.

Learn more about exercise and the immune system Learn more about exercise and the immune system

The immune system intersects with other systems

Research in the field of chronic itch have shown the importance and the complexity of the interactions between the immune system and the nervous system.

Learn more about why we itch Learn more about why we itch

We know that if you don’t get enough sleep, there’s changes in your immune function. Your immune function is how you fight diseases.”

Elizabeth Klerman

Professor of neurology, Harvard Medical School

Learn more about the relationship between sleep and the immune system

Investigating immune overreactions

Researchers identified a protein that can turn the immune system against the body’s own tissues, driving inflammation and tissue damage in a range of autoimmune and chronic inflammatory conditions. In other research, scientists discovered that vagus nerve cells that sense heat, irritation, and tissue damage also help prevent harmful immune overreactions, which could help prevent immune-driven damage in flu and other viral infections.

Studying innate immunity

Ranging from physical barriers like the skin to antimicrobial molecules produced by cells, the innate immune system is the body’s first line of defense. Scientists have identified proteins in the innate immune system that may be at the root of some neurodegenerative conditions, including ALS. Researchers are also studying how the innate immune system responds to RNA viruses, which cause diseases like COVID-19, influenza, and West Nile.

Exploring pathogen detection

Viruses, bacteria, and even certain kinds of cancers can rapidly mutate to try to escape our immune systems. Scientists are combining theoretical physics and evolutionary biology to learn how to better help our immune systems fight disease. Researchers are also working to understand what molecular patterns immune cells recognize, to learn when the immune system launches a response, leading to new ways to boost immune reactions.

Understanding immune cells

T cells are essential to the immune system, distinguishing between the body’s own tissues and harmful invaders. Research revealed how the body creates miniature versions of organs for T cells to “preview.” Scientists have also engineered an effective and fast way to create brain-specific immune cells to help model neurological disorders, and learned that one type of immune cell may be key to repairing damage to the lungs’ mucosal lining.

Explore the pioneering work Click to Play Video

Unleashing the immune system to fight cancer

Married for 47 years, and scientific collaborators for about as long, Arlene Sharpe and Gordon Freeman have dedicated their careers to unraveling the mysteries of the immune system and fulfilling the long-elusive promise of cancer immunotherapy.

Learn more about this research

Supercharging cancer treatments

Harvard researchers are expanding the current cancer immunotherapy treatments by identifying tricks that cancer cells use to hinder the ability of immune cells, exploring ways to make cancer cells contribute to their own elimination, and “tagging” T cells with immune-enhancing molecules to better fight solid tumors.

Adapting as cancer adapts

Harvard scientists are approaching the issue of cancer mutation in a number of ways, from creating novel ways to examine the gene history of cancer cells that are resistant to therapeutic drugs, to finding new ways to treat mutant strains of cancer.

Keeping cancer from coming back

Across Harvard, researchers are looking into the possibilities of personalized cancer vaccines for patients with kidney cancer at high risk of recurrence, stage 4 metastatic melanoma, and lymphoma, colon cancer, lung cancer, and neuroblastoma.

We’re trying to understand the difference between protective and failed immunity to TB.”

Sarah Fortune

Professor of immunology and infectious diseases, Harvard T.H. Chan School of Public Health

Learn more about her research on how the immune system controls tuberculosis

Antibiotic resistance

Bacteria that cause infections are developing resistance to commonly used antibiotics, creating a growing public health threat. Research is underway to develop effective treatments before bacteria outpace our current drugs.

Learn more about antibiotic resistance Learn more about antibiotic resistance

Bacterial infections

Because bacteria can attach to implants and form infections that are hard to treat, researchers developed biomaterial-based vaccines that train the immune system to recognize and attack these bacteria more effectively.

Learn more about the development Learn more about the development

Molecular differences

Researchers found that small molecular differences on the surface of gut bacteria help the immune system stay balanced and prevent harmful inflammation in the colon, which could have implications for diseases like Crohn’s and colitis.

Learn more about bacteria in the gut Learn more about bacteria in the gut

I want to understand how microbes affect our immunity and help protect us.”

Smita Gopinath

Assistant professor of immunology and infectious diseases, Harvard T.H. Chan School of Public Health

Learn more about her research on vaginal mucosa

Vaccinations are vital during measles outbreaks

Yonatan Grad, professor of immunology and infectious diseases at Harvard Chan School, explains that measles is extremely contagious, so those in proximity to the outbreaks should make sure that they have been vaccinated.

Vaccinations are vital during measles outbreaks

Finding new approaches to treat Long COVID

Finding new approaches to treat Long COVID

Utilizing a powerful preventative treatment against the AIDS virus

Utilizing a powerful preventative treatment against the AIDS virus

Exploring a unique approach for targeting all flu strains

Exploring a unique approach for targeting all flu strains

Decreasing cervical cancer screening frequency through HPV vaccination

Decreasing cervical cancer screening frequency through HPV vaccination

Strengthening efforts in pandemic preparedness and vaccine research

Strengthening efforts in pandemic preparedness and vaccine research

Understanding why pandemics keep going

Understanding why pandemics keep going

• Cancer
• HIV/AIDS
• Microorganisms