tetano
Editor, Senior Moderator
Microbiol Immunol
. 2022 May 24.
doi: 10.1111/1348-0421.13011. Online ahead of print.
Prevalence of Saliva Immunoglobulin A Antibodies Reactive with Severe Acute Respiratory Syndrome Coronavirus 2 among Japanese People Unexposed to the Virus
Keiichi Tsukinoki[SUP] 1 [/SUP], Tetsuro Yamamoto[SUP] 2 [/SUP], Jiro Saito[SUP] 3 [/SUP], Wakako Sakaguchi[SUP] 1 [/SUP], Keiichiro Iguchi[SUP] 4 [/SUP], Yoshinori Inoue[SUP] 5 [/SUP], Shigeru Ishii[SUP] 6 [/SUP], Chikatoshi Sato[SUP] 7 [/SUP], Mina Yokoyama[SUP] 5 [/SUP], Yuki Shiraishi[SUP] 2 [/SUP], Noriaki Kato[SUP] 2 [/SUP], Hiroyasu Shimada[SUP] 2 [/SUP], Akio Makabe[SUP] 8 [/SUP], Akihiro Saito[SUP] 8 [/SUP], Masanori Tanji[SUP] 2 [/SUP], Isao Nagaoka[SUP] 9 [/SUP], Juri Saruta[SUP] 10 [/SUP], Tetsutaro Yamaguchi[SUP] 4 [/SUP], Shigenari Kimoto[SUP] 5 [/SUP], Hideyo Yamaguchi[SUP] 2 11 [/SUP]
Affiliations
Abstract
While the COVID-19 pandemic caused by SARS-CoV-2 has posed a threat to public health as the number of cases and COVID-19-related deaths are increasing worldwide, the incidence of the virus infection are extremely low in Japan compared with many other countries. To explain this uncommon phenomenon, we investigated the prevalence of naturally occurring ("natural") antibodies, focusing on those of the secretory immunoglobulin A (sIgA) form, reactive with SARS-CoV-2 among Japanese people. One hundred and 80 healthy Japanese volunteers of a wide range of age who had been considered to be unexposed to SARS-CoV-2 participated in this study. Saliva samples and blood samples were collected from all of the 180 participants and 95 adults (aged ≥20 years) of them, respectively. The determination of saliva immunoglobulin A (IgA) antibodies, mostly comprising sIgA antibodies,, as well as serum IgA and immunoglobulin G (IgG) antibodies, reactive with the receptor binding domain of the SARS-CoV-2 spike-1 subunit proteins was conducted using an enzyme-linked immunosorbent assay. The major findings were that 52.78% (95%confidence interval [CI], 45.21 - 60.25%) of overall individuals who had not been exposed to SARS-CoV-2 were positive for saliva IgA antibodies with a wide range of levels between 0.002 and 3.272ng/mL, and that there may be a negative trend in positivity for the antibodies according to age. As we had expected, a frequent occurrence of assumble "natural" sIgA antibodies reactive with SARS-CoV-2 among the studied Japanese participant population was observed. This article is protected by copyright. All rights reserved.
Keywords: COVID-19; Japanese people; SARS-CoV-2; saliva IgA; secretory IgA; seroprevalence.
. 2022 May 24.
doi: 10.1111/1348-0421.13011. Online ahead of print.
Prevalence of Saliva Immunoglobulin A Antibodies Reactive with Severe Acute Respiratory Syndrome Coronavirus 2 among Japanese People Unexposed to the Virus
Keiichi Tsukinoki[SUP] 1 [/SUP], Tetsuro Yamamoto[SUP] 2 [/SUP], Jiro Saito[SUP] 3 [/SUP], Wakako Sakaguchi[SUP] 1 [/SUP], Keiichiro Iguchi[SUP] 4 [/SUP], Yoshinori Inoue[SUP] 5 [/SUP], Shigeru Ishii[SUP] 6 [/SUP], Chikatoshi Sato[SUP] 7 [/SUP], Mina Yokoyama[SUP] 5 [/SUP], Yuki Shiraishi[SUP] 2 [/SUP], Noriaki Kato[SUP] 2 [/SUP], Hiroyasu Shimada[SUP] 2 [/SUP], Akio Makabe[SUP] 8 [/SUP], Akihiro Saito[SUP] 8 [/SUP], Masanori Tanji[SUP] 2 [/SUP], Isao Nagaoka[SUP] 9 [/SUP], Juri Saruta[SUP] 10 [/SUP], Tetsutaro Yamaguchi[SUP] 4 [/SUP], Shigenari Kimoto[SUP] 5 [/SUP], Hideyo Yamaguchi[SUP] 2 11 [/SUP]
Affiliations
- PMID: 35607844
- DOI: 10.1111/1348-0421.13011
Abstract
While the COVID-19 pandemic caused by SARS-CoV-2 has posed a threat to public health as the number of cases and COVID-19-related deaths are increasing worldwide, the incidence of the virus infection are extremely low in Japan compared with many other countries. To explain this uncommon phenomenon, we investigated the prevalence of naturally occurring ("natural") antibodies, focusing on those of the secretory immunoglobulin A (sIgA) form, reactive with SARS-CoV-2 among Japanese people. One hundred and 80 healthy Japanese volunteers of a wide range of age who had been considered to be unexposed to SARS-CoV-2 participated in this study. Saliva samples and blood samples were collected from all of the 180 participants and 95 adults (aged ≥20 years) of them, respectively. The determination of saliva immunoglobulin A (IgA) antibodies, mostly comprising sIgA antibodies,, as well as serum IgA and immunoglobulin G (IgG) antibodies, reactive with the receptor binding domain of the SARS-CoV-2 spike-1 subunit proteins was conducted using an enzyme-linked immunosorbent assay. The major findings were that 52.78% (95%confidence interval [CI], 45.21 - 60.25%) of overall individuals who had not been exposed to SARS-CoV-2 were positive for saliva IgA antibodies with a wide range of levels between 0.002 and 3.272ng/mL, and that there may be a negative trend in positivity for the antibodies according to age. As we had expected, a frequent occurrence of assumble "natural" sIgA antibodies reactive with SARS-CoV-2 among the studied Japanese participant population was observed. This article is protected by copyright. All rights reserved.
Keywords: COVID-19; Japanese people; SARS-CoV-2; saliva IgA; secretory IgA; seroprevalence.