'Universal vaccine' protects mice against multiple pathogens

"Imagine if a nasal spray could make you immune not only to the viruses that cause COVID-19 and influenza, but to all respiratory diseases. In a paper published in Science today, researchers describe a vaccine that has done just that. When given to mice, the vaccine protected them for at least three months against multiple disease-causing viruses and bacteria - including the SARS-CoV-2 virus that causes COVID-19 - and even quelling responses to respiratory allergens."

"Bali Pulendran, an immunologist at Stanford University in Palo Alto, California, and his group previously studied the Bacillus Calmette-Guérin (BCG) vaccine, which provides temporary protection against numerous diseases and works by activating the innate immune system and keeping it active. This evolutionarily ancient system has a much broader reactivity than does the adaptive immune system - which is the one conventional vaccines utilize by teaching antibody-making B cells and T cells to recognize proteins found on specific pathogens."

"In the latest study, Pulendran's team developed a universal vaccine that targets the innate immune system, with three components. The first two are drugs that stimulate specific receptor proteins that can activate innate immune cells, such as macrophages that reside in the lungs. The third component stimulates a population of T cells, which are part of the adaptive immune system. Their task is to keep sending signals to the innate immune system to maintain its active state."

Researchers created a nasal vaccine that protected mice for at least three months against multiple respiratory viruses and bacteria, including SARS-CoV-2, and reduced respiratory-allergen responses. The vaccine targets the innate immune system and combines three components: two drugs that stimulate specific receptor proteins to activate innate immune cells such as lung macrophages, and a third component that activates T cells to continually signal and sustain innate activation. The formulation includes an immunogenic protein from chicken eggs. The innate immune system has broader reactivity than the adaptive system and can induce epithelial cells to resist infection. If safely effective in humans, the vaccine could be administered seasonally to provide broad first-line defense against respiratory infections and future pandemics.

Read at Nature