The immune system inside the nose works better when it's warm. Otherwise, it is easier for viruses and bacteria to infect a person, researchers from the University of Massachusetts found. The findings are published in the Journal of Allergy and Clinical Immunology.
Scientists had previously discovered that extracellular vesicles - vesicles that can help the body fight off infectious agents - are secreted inside the nose. It is the vesicles, like a swarm of bees, that attack and destroy bacteria.
In the new work, the researchers experimented with nasal mucosa that was taken from volunteers during the removal of nasal polyps. They also used a substance that mimicked a viral infection to trigger an immune response.
The specialists divided the mucosal cell samples into two groups and cultured them in the lab, exposing one set of samples to plus temperature and the other to minus temperature. In heat, the immune system successfully coped with viruses, but at lower temperatures, the tissue released fewer "bubbles", which reduced cell protection.
In the future, scientists plan to continue studying the nasal immune response to various pathogens.