Monoclonal Antibody Targeting the HA191/199 Region of H1N1 Influenza Virus Mediates the Damage of Neural Cells

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Chun-Yan Guo^1,2,a*, Qing Feng^1,2, Li-Ting Yan^1,2, Xin Xie³, Dao-Yan Liang^1,2, Yan Li^1,2, Yang-Meng Feng^1,2, Li-Jun Sun^1,2,b*, and Jun Hu^1,2,c*

¹Central Laboratory of Shaanxi Provincial People’s Hospital, Xi’an, Shaanxi 710068, China

²Shaanxi Province Research Center of Cell Immunological Engineering and Technology, Xi’an, Shaanxi 710068, China

³Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi’an, Shaanxi 710069, China

^* To whom correspondence should be addressed.

Received June 29, 2021; Revised September 30, 2021; Accepted September 30, 2021

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Vaccination is the most effective mean of preventing influenza virus infections. However, vaccination-induced adverse reactions of the nervous system, the causes of which are unknown, lead to concerns on the safety of influenza A vaccine. In this study, we used flow cytometry, cell ELISA, and immunofluorescence to find that H1-84 monoclonal antibody (mAb) against the191/199 region of the H1N1 influenza virus hemagglutinin (HA) protein binds to neural cells and mediates cell damage. Using molecular simulation software, such as PyMOL and PDB viewer, we demonstrated that the HA191/199 region maintains the overall structure of the HA head. Since the HA191/199 region cannot be removed from the HA structure, it has to be altered via introducing point mutations by site-directed mutagenesis. This will provide an innovative theoretical support for the subsequent modification the influenza A vaccine for increasing its safety.

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KEY WORDS: influenza A virus, HA191/199 region, monoclonal antibodies (mAbs), neuronal cell damage

DOI: 10.1134/S0006297921110109

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