This vaccine could stop the next pandemic | The Economist

TL;DR

Training the innate immune system with broad-spectrum vaccines could provide early pandemic protection before specific vaccines are developed.

Key Points

• 1.The immune system has two key components with different speeds. The innate immune system acts as a fast first defense, while the adaptive immune system (B and T cells) takes days to mount a specific response but creates memory for future encounters.
• 2.The innate immune system can be 'trained,' overturning decades of scientific consensus. Research over the past 15 years, pioneered by Mihai Netea at Radboud University in the Netherlands, showed the BCG tuberculosis vaccine reshapes innate immunity to protect against a broad range of diseases.
• 3.BCG vaccine causes epigenetic changes that keep innate immune cells on high alert. It 'bookmarks' parts of the genome in myeloid cells, keeping them activated longer and enhancing communication between the innate and adaptive immune systems.
• 4.Stanford researchers are attempting to engineer a targeted broad-spectrum vaccine based on BCG's mechanism. The approach aims to make innate immune cells hypervigilant in specific areas like the lungs, and in mouse studies it protected against viruses, bacteria, and even allergens — though human trials remain unproven.
• 5.Broad-spectrum vaccines would complement, not replace, specific vaccines. Scientists envision universal vaccines given alongside strain-specific ones; during COVID-19, a universal coronavirus vaccine could have saved millions of lives before targeted vaccines were ready, even if offering less precise protection.