According to a study published in the Journal of Allergy and Clinical Immunology and as first reported by CNN, the winter weather heralds the beginning of cold and flu season, where nearly everyone you know has a case of the sniffles. It appears to hit with the first winter breeze, like a flurry of cold and flu viruses.
As per the study, scientists have found a molecular explanation for why more people get respiratory illnesses during the winter. Cold air dampens the immunological response in the nose.
Dr. Zara Patel, an otolaryngologist and head and neck surgeon at Stanford University School of Medicine, commented, “This is the first time we have a biologic, molecular explanation for one piece of our innate immune response that appears to be lowered by cooler temperatures.”
The study also mentions that a decrease of 9 degrees Fahrenheit (5 degrees Celsius) kills around half of the billions of cells in the nostrils that fight viruses and bacteria. “Cold air is associated with higher viral infection because you’ve effectively lost half your immunity merely by changing the temperature,” explains Dr. Benjamin Bleier, director of otolaryngology at Massachusetts Eye and Ear and associate professor at Harvard Medical School in Boston.
Even though human tissue is being used in the lab to explore this immune response, Patel underlined in an email that the study is not being conducted inside a natural person’s nose.
A virus or bacterium in the respiratory system is frequently introduced into the body through the nose. Researchers discovered that the front of the nose senses an intruder before the rear of the nose is aware of the threat. Extracellular vesicles (EVs), which are cell-like entities that may operate independently, are quickly produced by nose-lining cells.
Despite their inability to increase like normal cells, Bleier compares EVs to “small copies of cells” sent out to kill viruses. When someone inhales a virus, the virus binds to the EVs rather than the cells because the EVs behave as decoys. The study discovered that in response to a nasal assault, the formation of extracellular vesicles rose by 160%.
The billions of extracellular vesicles in the nasal passages were far more effective in preventing viral transmission than the initial cells because they had much more receptors on their surface. “Imagine receptors as little arms extending out, trying to grip onto them,” Bleier said of the immune system’s reaction to inhaled virus particles. We also discovered that the cysts are incredibly sticky because their surfaces contain up to twenty times the number of receptors as typical.
MicroRNA is a naturally produced viral killer found in human cells that aids the body’s defense against infectious microorganisms. However, researchers discovered that EVs in the nose had 13 times the number of microRNA sequences as normal cells.
