Scientists recently developed a nasal spray to protect against multiple respiratory illnesses, including seasonal influenza and COVID-19, and tested it on mice for three months. They call this promising invention a “universal respiratory vaccine,” but it doesn’t stimulate the immune system like traditional vaccines.

you may like

seek universal protection

The push for a universal vaccine accelerated after the COVID-19 pandemic, which exposed how vulnerable the world is to new respiratory pathogens and how quickly existing vaccines become obsolete in the face of mutations. Since then, researchers have focused on developing vaccines that last longer and protect against more variants, which could reduce the need to frequently update vaccine formulations.

A universal vaccine is under development

For example, in the case of influenza, researchers are targeting the hemagglutinin protein that protrudes from the surface of the virus, but they are focusing on the stalk rather than the head because the stalk mutates more slowly. The National Institutes of Health’s (NIH) FluMos-v2, which targets hemagglutinin in six influenza strains, recently completed early-stage human clinical trials and generated a promising immune response.

What to read next

Meanwhile, some scientists are working on developing a pancoronavirus vaccine to protect against current and future coronaviruses, while others are researching AI-designed vaccines. They build these using computational tools to identify regions of viral proteins that mutate very slowly and appear in many viruses.これらの取り組みはどちらもまだ初期の実験段階にあります。

evoke natural immunity

“these [lung]

The concept is based on research into the Bacillus Calmette-Guérin (BCG) vaccine to prevent tuberculosis. In 2023, Pulendran et al. found that T cells clustered in the lungs of mice given BCG. There, they released a signal that kept innate immune cells in the lungs activated for months, protecting the mice from both COVID-19 and influenza.

この新しい点鼻スプレーは、同様の免疫保護を引き起こします。 It combines two adjuvants, substances that trigger an immune response, to activate T cells and attract them to the lungs. These T cells send chemical signals that mimic natural infection cues, activating the lung’s natural cells and keeping them on high alert.病原体が肺に侵入すると、自然免疫細胞が感染の芽を摘み取る準備を整えます。

The vaccine also helped mice prevent bacterial infections caused by Acinetobacter baumannii and Staphylococcus aureus weeks to months after administration. For example, levels of Staphylococcus aureus in the kidneys were about 200 times lower in vaccinated mice than in unvaccinated mice.

このワクチンは、イエダニによって引き起こされるアレルギー反応の重症度も軽減しました。 The vaccine implants long-lived T cells in the lungs, altering the lung environment and suppressing the immune pathways behind allergies, the researchers reported. As a result, when vaccinated mice encountered dust mites, their immune systems did not recruit cells that cause inflammation or produce mucus as they would otherwise. T 細胞を除去すると、この保護は失われます。

“This concept establishes a stronger and faster immune posture in the respiratory tract,” Mena Lora, who was not involved in the study, said of the nasal spray.結果はまだ初期段階だが、この研究は重要な概念実証を提供すると彼は付け加えた。

Because this study tested only a small number of pathogens, the vaccine provides broad protection, but it is too early to declare it a universal respiratory vaccine. And in the long term, translating these findings to humans will be complicated.

Purendran agreed, adding that stimulating the immune system in this way comes with potential risks, including causing excessive inflammation. 「私たちの動物実験では、病的な炎症は観察されませんでしたが、人間の研究ではこれらの問題を注意深く検討する必要があります」と同氏は警告した。

The research team is currently preparing for early-stage trials in humans.承認の可能性までの正確なスケジュールは依然として不透明です。

“If a vaccine like this is successful, it could reduce hospitalizations and make ICUs easier.” [intensive care unit] It burdens and protects people during seasonal epidemics and future pandemics,” Mena Lora said.

The World Health Organization estimates that if next-generation or universal influenza vaccines are widely used between 2025 and 2050, they could prevent up to 18 billion cases of influenza worldwide and save millions of lives. However, these ambitious goals remain on hold as a universal influenza vaccine is not yet available on the market.