Abstract
Human adenoviruses type 4 (HAdV4) and 7 (HAdV7) are two major respiratory pathogens and sporadically cause outbreaks of acute respiratory diseases. The neutralizing antibody (nAb) response to these two adenoviruses in civilian populations, which is important for dissecting previous circulations and predicting potential outbreaks, remains largely unknown. In this study, we generated replication-competent HAdV4 and HAdV7 reporter viruses expressing secreted-alkaline-phosphatase (SEAP), and established neutralization assays to investigate the seroprevalence of pre-existing nAb in healthy volunteers from Hunan Province, southern China. The seropositivity rates are 58.4 and 63.8% for anti-HAdV4 nAb and anti-HAdV7 nAb, respectively. High nAb titers (> 1000) were frequently detected in HAdV4-seropositive individuals, whereas most HAdV7-seropositive volunteers had moderate nAb titers (201–1000). The seropositivity rates of anti-HAdV4 nAb and anti-HAdV7 nAb increase with age, with individuals younger than 20 exhibiting the lowest seropositivity rates. Both seropositivity rates and nAb titers are comparable between different sex groups. Notably, HAdV4-seropositive individuals tend to be HAdV7-seropositive and vice versa. Because HAdV4 antisera showed no neutralizing activity to HAdV7 whereas HAdV7 antisera cannot neutralize HAdV4, a subgroup of individuals might be susceptible to infection by HAdV4 and HAdV7 and thus generate nAb to both of them. These results revealed the continuous circulation of HAdV4 and HAdV7 and the lack of protective immunity in more than 35% of people, which emphasized the surveillance of these two HAdVs and the development of prophylactic vaccines.
Highlights
Human adenoviruses (HAdVs) are non-enveloped, double-stranded DNA viruses belonging to Adenoviridae
We investigated the seroprevalence of anti-Human adenoviruses type 4 (HAdV4) neutralizing antibody (nAb) and antiHAdV7 nAb in a civilian cohort from Hunan Province, southern China
SEAP expression in cells infected with HAdV4-SEAP was only suppressed by HAdV4 antisera but not significantly influenced by HAdV7 antisera, whereas SEAP expression in HAdV7-SEAP infected cells was only inhibited by HAdV7 antisera but not HAdV4 antisera
Summary
Human adenoviruses (HAdVs) are non-enveloped, double-stranded DNA viruses belonging to Adenoviridae. HAdVs are common pathogens responsible for a variety of diseases, Seroprevalence of HAdV4 and HAdV7 including acute respiratory disease (ARD), conjunctivitis, gastroenteritis, urinary infection and meningoencephalitis (Ghebremedhin, 2014; Radke and Cook, 2018). HAdV infection in immuno-competent healthy adults is usually asymptomatic (Berciaud et al, 2012). In particular populations such as immuno-compromised individuals, infants, and children, HAdV infections may lead to severe and even fatal diseases (Ghebremedhin, 2014; Radke and Cook, 2018). Outbreaks of HAdV infection are frequently reported in crowded populations such as school students and military recruits (Ghebremedhin, 2014)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
