ABSTRACT
The coronavirus SARS-CoV-2 has a severe impact on global public health, and the emerging variants threaten the efficacy of the circulating vaccines. Here, we report that a single vaccination with a non-replicating chimpanzee adenovirus-based vaccine against the SARS-CoV-2 Delta variant (JS1-delta) elicits potent humoral, cellular and mucosal immunity in mice. Additionally, a single intranasal administration of JS1-delta provides effective protection against the Delta (B.1.617.2) variant challenge in mice. This study indicates that chimpanzee adenovirus type 3 (ChAd3) derived vector represents a promising platform for antiviral vaccine development against respiratory infections and JS1-delta is worth further investigation in human clinical trials. HighlightsO_LIA new chimpanzee adenoviral vaccine against the SARS-CoV-2 Delta variant was developed. C_LIO_LIThe vaccine elicited potent humoral, cellular and mucosal immunity in mice. C_LIO_LIThe vaccine protected mice from the Delta variant challenge. C_LI
ABSTRACT
Objective To study the relationship of HPV pseudo-neutralizing titers detected by two different reporter genes: Zoanthus sp. green fluorescent protein (ZsGreen) and secreted alkaline phosphatase (SEAP) , and the relationship between HPV the pseudovirus-neutralizing antibody titer and the antibody titer determined by ELISA method. Methods The plasmids with expression cassettes of the HPV capsid protein L1 and L2 genes after codon optimization and the plasmid with reporter gene (ZsGreen or SEAP) were co-transfected into 293FT cells. The cell lysate supernatants were collected after 48 h culture, then the pseudovirus was purified through POROS column chromatography from the supernatants. After the titer of pseudovirus bulk were measured, HPV-16 and HPV-18 pseudovirus-neutralization assays were carried out for determining the titer of sera collected from immunized mice with HPV candidate vaccine and Gardasil HPV vaccine. Results In statistical analysis, the two reporter gene systems for the detection of the pseudovirus neutralizing antibody titer are highly relevant to each other (Spearman coefficient; r = 0. 760). And their neutralizing antibody titers bear a high degree of correlation with the antibody titer (Spearman coefficient: r= 0.577 and r =0. 741). Conclusion ZsGreen and SEAP pseudovirus neutralizing antibody titers are highly relevant to each other. The neutralizing antibody and the antibody titer are also relevant. These results reveal some mechanism of HPV vaccines to prevent the virus from invading the host cells, and are absolutely useful in the protection efficiency evaluation of the HPV-16 and HPV-18 candidate vaccines.
