Potent neutralization antibodies induced by a recombinant trimeric Spike protein vaccine candidate containing PIKA adjuvant for COVID-19
This article has been Reviewed by the following groups
Discuss this preprint
Start a discussion What are Sciety discussions?Listed in
- Evaluated articles (ScreenIT)
Abstract
Neutralizing antibodies are critical to prevent corona virus infection. The structures of immunogens to elicit most potent neutralization antibodies are still under investigation. Here we tested the immunogenicity of the trimeric, full length Spike protein with 2 proline mutations to preserve its prefusion conformation. Recombinant trimeric Spike protein expressed by CHO cells was used with polyI:C (PIKA) adjuvant to immunize mice by 0-7-14 day schedule. The results showed that Spike-specific antibody was induced at day 21 with titer of more than 50,000 in average as measured by direct binding to Spike protein. The titer of neutralization reached more than 1000 in average when tested by a pseudo-virus system, using monoclonal antibodies (40592-MM57 and 40591-MM43) with neutralizing IC50 at 1 μg/ml as standards. Protein/peptide array showed that the antibodies induced by trimeric S protein vaccine bind similarly to natural infection with the receptor binding domain (RBD) as major immunodominant region. No linear epitopes were found in RBD, although several linear epitopes were found in C-terminal domain right after RBD, and heptad repeat regions. Our study supports the efficacy of recombinant trimeric Spike protein vaccine candidate for COVID-19, with excellent safety and readiness for storage and distribution in developing countries.
Article activity feed
-
SciScore for 10.1101/2021.02.17.431647: (What is this?)
Please note, not all rigor criteria are appropriate for all manuscripts.
Table 1: Rigor
Institutional Review Board Statement IRB: Vaccination in mice: Animal experiments were approved by the institutional board of Tongji University School of Medicine. Randomization not detected. Blinding not detected. Power Analysis not detected. Sex as a biological variable not detected. Cell Line Authentication not detected. Table 2: Resources
Antibodies Sentences Resources The arrays were washed with PBST and bound antibodies were detected by incubating with Cy3-conjugated goat anti-mouse IgG (Jackson ImmunoResearch, PA, USA), which were diluted for 1: 1,000 in PBST. anti-mouse IgGsuggested: NoneExperimental Models: Cell Lines Sentences Resources The plasmid was transfected to 293T cells and the recombinant S protein … SciScore for 10.1101/2021.02.17.431647: (What is this?)
Please note, not all rigor criteria are appropriate for all manuscripts.
Table 1: Rigor
Institutional Review Board Statement IRB: Vaccination in mice: Animal experiments were approved by the institutional board of Tongji University School of Medicine. Randomization not detected. Blinding not detected. Power Analysis not detected. Sex as a biological variable not detected. Cell Line Authentication not detected. Table 2: Resources
Antibodies Sentences Resources The arrays were washed with PBST and bound antibodies were detected by incubating with Cy3-conjugated goat anti-mouse IgG (Jackson ImmunoResearch, PA, USA), which were diluted for 1: 1,000 in PBST. anti-mouse IgGsuggested: NoneExperimental Models: Cell Lines Sentences Resources The plasmid was transfected to 293T cells and the recombinant S protein trimers were purified by Ni-NTA (nickel-nitrilotriacetic acid) chromatography (QIAGEN, Germany), followed by size exclusion to further purify the trimers. 293Tsuggested: NCBI_Iran Cat# C498, RRID:CVCL_0063)The plasmids of 9μg pHAGE-luciferase-GFP、 psPAX2 and Zhou-COVID-19-Spike were co-transfected into HEK293T cells by using 1 μg/mL polyetherimide (Polysciences, Warrington, PA) in DMEM medium containing 10% FCS. HEK293Tsuggested: NoneThe mixtures of pseudo-viruses and antibodies were added to 293T/ACE2 cells. 293T/ACE2suggested: RRID:CVCL_YZ65)Experimental Models: Organisms/Strains Sentences Resources C57BL/6 mice at 6 to 8 weeks old were immunized by intramuscular injection of PIKA-S-trimer vaccine or PIKA-S-monomer vaccine. C57BL/6suggested: NoneSoftware and Algorithms Sentences Resources The absorbance was measured at 450 nm and the antibody titer was calculated with GraphPad Prism 7.0 (San Diego, CA). GraphPad Prismsuggested: (GraphPad Prism, RRID:SCR_002798)The 50% neutralization dose was calculated using GraphPad Prism 7.0 (San Diego, CA). GraphPadsuggested: (GraphPad Prism, RRID:SCR_002798)Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).
Results from LimitationRecognizer: An explicit section about the limitations of the techniques employed in this study was not found. We encourage authors to address study limitations.Results from TrialIdentifier: No clinical trial numbers were referenced.
Results from Barzooka: We did not find any issues relating to the usage of bar graphs.
Results from JetFighter: We did not find any issues relating to colormaps.
Results from rtransparent:- Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
- Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
- No protocol registration statement was detected.
-
