Puff of Protection: China’s Major Leap in Inhalable Vaccine Technology

Researchers at the Chinese Academy of Sciences developed an innovative inhalable, single-dose vaccine using a “nano-micro composite” structure. This vaccine effectively blocks respiratory infections and is suitable for areas with limited refrigeration, representing a major advancement in vaccine technology.

Researchers from the Institute of Process Engineering (IPE) of the Chinese Academy of Sciences have proposed a new “nano-micro composite” delivery concept for vaccines. Based on this idea, they have developed a single-dose, dry-powder, inhalable vaccine platform using nano-micro composite multilevel structures, which has been successfully prepared in the laboratory, and the vaccine has been shown to be effective in blocking respiratory viral infection and transmission in animal models. This platform holds great promise for combating future emerging and epidemic infectious diseases.

This study was published today (December 13) in the journal Nature.

Challenges in Current Vaccine Approaches

In recent years, researchers have made significant progress in developing vaccines for infectious respiratory diseases. However, most of these vaccines are administered through intramuscular injection, which primarily induces a humoral immune response and relies on blood antibodies to neutralize the virusA virus is a tiny infectious agent that is not considered a living organism. It consists of genetic material, either DNA or RNA, that is surrounded by a protein coat called a capsid. Some viruses also have an outer envelope made up of lipids that surrounds the capsid. Viruses can infect a wide range of organisms, including humans, animals, plants, and even bacteria. They rely on host cells to replicate and multiply, hijacking the cell's machinery to make copies of themselves. This process can cause damage to the host cell and lead to various diseases, ranging from mild to severe. Common viral infections include the flu, colds, HIV, and COVID-19. Vaccines and antiviral medications can help prevent and treat viral infections.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]” tabindex=”0″ role=”link”>virus. Unfortunately, this approach fails to trigger a mucosal immune response and establish a robust immune barrier in the respiratory tract.

Moreover, adjuvants commonly used in current vaccines, e.g., aluminum adjuvants, are unable to induce cellular immune responses and are ineffective in combating rapid viral mutations. Additionally, the current liquid form of vaccines necessitates strict low-temperature storage conditions, and the two- or three-dose vaccination schedule also impacts the overall vaccination rate.

Construction and mechanism of single-dose, dry-powder inhalation vaccine. Credit: Guanghui Ma’s Group

Cross-disciplinary Collaboration Yields New Vaccine Platform

To address these problems, interdisciplinary integration and innovative research concepts are needed to develop safer and more efficient vaccines for respiratory infections.

Taking this approach, Prof. Wei Wei and Prof. MA Guanghui, from the State Key Laboratory of Biochemical Engineering at IPE, in cross-disciplinary collaboration with Prof. Hengliang Wang and Prof. Li Zhu, from the State Key Laboratory of Pathogen and Biosecurity, have developed a new vaccine platform to tackle these challenges.

This platform combines biodegradable microspheres with protein nanoparticles. The surface of these nanoparticles can simultaneously display multiple antigens, thus inducing a broad-spectrum immune response and expanding the range of vaccine protection. It also allows for the quick and convenient development of other respiratory virus vaccines due to the flexibility of antigen presentation.

Moreover, the platform’s unique nano-micro composite structure enables an efficient immune response in the lungs by facilitating high-performance delivery. Once the antigen-nanoparticles are released, they can be efficiently taken up by antigen-presenting cells.

Additionally, this dry powder vaccine significantly reduces storage and transportation costs, making it suitable for areas with limited refrigeration facilities, thus improving immunization rates.

Long-Lasting Immunity and Potential for Clinical Translation

Furthermore, the sustained release of antigens in the vaccine induces long-lasting humoral, cellular, and mucosal immunity with just a single inhalation. In later cooperation with Prof. HE Zhanlong of the Institute of Medical Biology of the Chinese Academy of Medical SciencesThe Academy of Medical Sciences is an organization that was established in the UK in 1998. It is one of the four UK National Academies, the others being the British Academy, the Royal Academy of Engineering, and the Royal Society.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]” tabindex=”0″ role=”link”>Academy of Medical Sciences, the researchers developed a model of airborne protection, close contact protection, and airborne transmission blocking, which described the benefits of inhaled vaccine for preventing the virus infection and transmission.

“The components of this nano-micro system used natural proteins and approved polymer materials, and the effectiveness and safety of the vaccine have been systematically studied in non-human primates, indicating its great potential for clinical translation,” said Prof. Wei Wei.

Reference: “Inhaled SARS-CoV-2Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the official name of the virus strain that causes coronavirus disease (COVID-19). Previous to this name being adopted, it was commonly referred to as the 2019 novel coronavirus (2019-nCoV), the Wuhan coronavirus, or the Wuhan virus.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]” tabindex=”0″ role=”link”>SARS-CoV-2 vaccine for single-dose dry powder aerosol immunization” by Tong Ye, Zhouguang Jiao, Xin Li, Zhanlong He, Yanyan Li, Fengmei Yang, Xin Zhao, Youchun Wang, Weijin Huang, Meng Qin, Yingmei Feng, Yefeng Qiu, Wenhui Yang, Lingfei Hu, Yaling Hu, Yu Zhai, Erqiang Wang, Di Yu, Shuang Wang, Hua Yue, Yishu Wang, Hengliang Wang, Li Zhu, Guanghui Ma and Wei Wei, 13 December 2023, Nature.
DOI: 10.1038/s41586-023-06809-8