tetano
Editor, Senior Moderator
Viruses
. 2020 Jul 20;12(7):E780.
doi: 10.3390/v12070780.
Comparative Analyses of the Antiviral Activities of IgG and IgA Antibodies to Influenza A Virus M2 Protein
Kosuke Okuya[SUP] 1 [/SUP], Nao Eguchi[SUP] 1 [/SUP], Rashid Manzoor[SUP] 1 [/SUP], Reiko Yoshida[SUP] 1 [/SUP], Shinji Saito[SUP] 2 [/SUP], Tadaki Suzuki[SUP] 3 [/SUP], Michihito Sasaki[SUP] 4 [/SUP], Takeshi Saito[SUP] 1 [/SUP], Yurie Kida[SUP] 1 [/SUP], Akina Mori-Kajihara[SUP] 1 [/SUP], Hiroko Miyamoto[SUP] 1 [/SUP], Osamu Ichii[SUP] 5 [/SUP], Masahiro Kajihara[SUP] 1 [/SUP], Hideaki Higashi[SUP] 6 7 [/SUP], Ayato Takada[SUP] 1 7 [/SUP]
Affiliations
Abstract
The influenza A virus (IAV) matrix-2 (M2) protein is an antigenically conserved viral envelope protein that plays an important role in virus budding together with another envelope protein, hemagglutinin (HA). An M2-specific mouse monoclonal IgG antibody, rM2ss23, which binds to the ectodomain of the M2 protein, has been shown to be a non-neutralizing antibody, but inhibits plaque formation of IAV strains. In this study, we generated chimeric rM2ss23 (ch-rM2ss23) IgG and IgA antibodies with the same variable region and compared their antiviral activities. Using gel chromatography, ch-rM2ss23 IgA were divided into three antibody subsets: monomeric IgA (m-IgA), dimeric IgA (d-IgA), and trimeric and tetrameric IgA (t/q-IgA). We found that t/q-IgA had a significantly higher capacity to reduce the plaque size of IAVs than IgG and m-IgA, most likely due to the decreased number of progeny virus particles produced from infected cells. Interestingly, HA-M2 colocalization was remarkably reduced on the infected cell surface in the presence of ch-rM2ss23 antibodies. These results indicate that anti-M2 polymeric IgA restricts IAV budding more efficiently than IgG and suggest a role of anti-M2 IgA in cross-protective immunity to IAVs.
Keywords: IgA; antibody; budding inhibition; cross-protective immunity; influenza A virus; matrix 2 protein.
. 2020 Jul 20;12(7):E780.
doi: 10.3390/v12070780.
Comparative Analyses of the Antiviral Activities of IgG and IgA Antibodies to Influenza A Virus M2 Protein
Kosuke Okuya[SUP] 1 [/SUP], Nao Eguchi[SUP] 1 [/SUP], Rashid Manzoor[SUP] 1 [/SUP], Reiko Yoshida[SUP] 1 [/SUP], Shinji Saito[SUP] 2 [/SUP], Tadaki Suzuki[SUP] 3 [/SUP], Michihito Sasaki[SUP] 4 [/SUP], Takeshi Saito[SUP] 1 [/SUP], Yurie Kida[SUP] 1 [/SUP], Akina Mori-Kajihara[SUP] 1 [/SUP], Hiroko Miyamoto[SUP] 1 [/SUP], Osamu Ichii[SUP] 5 [/SUP], Masahiro Kajihara[SUP] 1 [/SUP], Hideaki Higashi[SUP] 6 7 [/SUP], Ayato Takada[SUP] 1 7 [/SUP]
Affiliations
- PMID: 32698456
- DOI: 10.3390/v12070780
Abstract
The influenza A virus (IAV) matrix-2 (M2) protein is an antigenically conserved viral envelope protein that plays an important role in virus budding together with another envelope protein, hemagglutinin (HA). An M2-specific mouse monoclonal IgG antibody, rM2ss23, which binds to the ectodomain of the M2 protein, has been shown to be a non-neutralizing antibody, but inhibits plaque formation of IAV strains. In this study, we generated chimeric rM2ss23 (ch-rM2ss23) IgG and IgA antibodies with the same variable region and compared their antiviral activities. Using gel chromatography, ch-rM2ss23 IgA were divided into three antibody subsets: monomeric IgA (m-IgA), dimeric IgA (d-IgA), and trimeric and tetrameric IgA (t/q-IgA). We found that t/q-IgA had a significantly higher capacity to reduce the plaque size of IAVs than IgG and m-IgA, most likely due to the decreased number of progeny virus particles produced from infected cells. Interestingly, HA-M2 colocalization was remarkably reduced on the infected cell surface in the presence of ch-rM2ss23 antibodies. These results indicate that anti-M2 polymeric IgA restricts IAV budding more efficiently than IgG and suggest a role of anti-M2 IgA in cross-protective immunity to IAVs.
Keywords: IgA; antibody; budding inhibition; cross-protective immunity; influenza A virus; matrix 2 protein.