NTU Developing COVID-19 Nasal Spray Vaccine Against Delta Variant 台大鼻噴新冠疫苗 初步實驗可抗Delta

A COVID-19 nasal spray vaccine is currently being developed by the National Taiwan University Hospital. with human testing likely to take place in 2022.
 


Over 77 percent of people in Taiwan have been vaccinated with at least one dose of COVID-19 vaccine up-to-date, but there is still about 20 percent that has not received any shots. The National Taiwan University Hospital (NTUH) is currently in the works of developing a COVID-19 nasal spray vaccine to encourage people who are not yet vaccinated. The intranasal spray's protection comes from nanoparticles that carry bits of harmless, virus-mimicking DNA that trigger a generation of IgG antibodies. In addition to boosting immunity, the molecules generated by the spray act as a physical blockade against viral infection, including the Delta strain, by limiting the amount of virus that can settle into the nasal passages and travel into the lungs, potentially reducing transmission to others. So far, the aerosolized vaccine has been delivered only in the snouts of mice, but it's shown promise in protecting against a pseudovirus that closely resembles the COVID-19 virus.

Huang Li-min, Superintendent, National Taiwan University Children's Hospital: “It's a nasal spray. The convenience is the attraction, because first of all, you don't have to get stabbed by a needle, and second, it produces IgA (immunoglobulin A), which in theory helps to reduce transmission to others.”

Neutralizing antibody levels are highly predictive of immune protection from COVID-19 infections, but antibody tests using live viruses need to be conducted in a biosafety level-3 laboratory. To make the process easier, the NTUH instead utilizes the latest ELISA antibody detection test for COVID-19 and designs the test based on the receptor-binding domain of the Delta variant and the human enzyme ACE2.

Huang Li-min, Superintendent, National Taiwan University Children's Hospital: “We could probably do fewer tests in the level-3 laboratory in the future and just retrieve blood samples and conduct an ELISA test. ELISA tests can be done in normal laboratories. It's fast and convenient; hundreds and thousands of tests can be conducted each day.”

Taiwan's research team says that most vaccines available on the market now are based on the original Wuhan strain. To prevent breakthrough infections, many countries are now in the process of developing new generations of vaccines. The NTUH is also active in the talks with Taiwan's biotechnology companies to develop and produce the COVID-19 nasal spray vaccine. Human testing will likely take place during the first half of 2022. 

 

 

 

國內新冠疫苗第一劑涵蓋率超過七成七,不過仍有兩成多民眾連一劑都沒打;為了提高疫苗接種意願,台大醫院利用新的黏膜佐劑技術,研究開發新的鼻噴式新冠疫苗,除了產生IgG抗體外,也會產生可以覆蓋到上呼吸道的IgA抗體,可有效對抗Delta病毒,減少突破性感染,在老鼠實驗、初步獲得驗證可行。

台大兒童醫院院長黃立民表示:「這是噴鼻的,所以當然本身是有一些吸引力,因為第一個,你不用打針,第二個它會產生IgA免疫球蛋白,所以理論上,它可以比較減少病毒的傳播。」

此外,體內中和抗體濃度代表對抗新冠肺炎的能力,但測中和抗體必須進第三級實驗室,利用活病毒做實驗才能檢驗,過程十分繁瑣;不過台大研究團隊根據Delta病毒株RBD及人類ACE2,設計出可測量、目前流行的Delta變異株中和抗體的ELISA套組,讓中和抗體得以快速檢測。

台大兒童醫院院長黃立民解釋:「將來,我們說不定就可以,不必每一次都進第三級實驗室,就可以抽個血做ELISA就可以了。這個在一般的實驗室做,很快又很方便,一天可以幾百個、幾千個檢體。」

研究團隊強調,目前全球上市的疫苗都是針對原始武漢病毒株,但隨著變異株陸續出現,各國都在積極研發新疫苗,希望減少突破性感染。台大這項新的研究發現,正尋找國內生技業者合作,期待明年上半年有機會進入人體試驗。

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