Pre-clinical testing of two serologically distinct chimpanzee-origin adenovirus vectors expressing spike of SARS-CoV-2
This article has been Reviewed by the following groups
Listed in
- Evaluated articles (ScreenIT)
Abstract
Two serologically distinct chimpanzee-origin, replication-defective adenovirus (AdC) vectors expressing the spike (S) protein of an early severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) isolate were generated and tested for induction of antibodies in young and aged mice. Both vectors induced S protein-specific antibodies including neutralizing antibodies. Levels of antibodies increased after a boost. The effectiveness of the boost depended on vector dose and timing between the two immunizations. Using two heterologous AdC vectors was more effective than vaccinating with the same vector repeatedly. Antibodies partially crossreacted between different S protein variants. Cross-reactivity increased after booster immunization with vectors carrying the same S gene, expression of two different S proteins by the AdC vectors used for the prime and the boost did not selectively increase responses against the variants.
Article activity feed
-
SciScore for 10.1101/2022.02.23.481620: (What is this?)
Please note, not all rigor criteria are appropriate for all manuscripts.
Table 1: Rigor
Ethics not detected. Sex as a biological variable Mice and mouse procedures: Female C57Bl/6 mice (6–8 weeks of age) were purchased from the Jackson Laboratories (Bar Harbor, ME). Randomization not detected. Blinding not detected. Power Analysis not detected. Cell Line Authentication not detected. Table 2: Resources
Antibodies Sentences Resources Expression of ACE-2: Cells diluted to 1 × 106 per microtiter plate well were incubated for 45 min at room temperature with a 1 in 100 dilution of a mouse IgG2a antibody to human/hamster ACE-2 (clone 171606 R&D Systems, Minneapolis, MN) mouse IgG2asuggested: (Millipore Cat# 171606-100UG, RRID:AB_10690063)In parallel the membrane was probed with a mouse monoclonal IgG … SciScore for 10.1101/2022.02.23.481620: (What is this?)
Please note, not all rigor criteria are appropriate for all manuscripts.
Table 1: Rigor
Ethics not detected. Sex as a biological variable Mice and mouse procedures: Female C57Bl/6 mice (6–8 weeks of age) were purchased from the Jackson Laboratories (Bar Harbor, ME). Randomization not detected. Blinding not detected. Power Analysis not detected. Cell Line Authentication not detected. Table 2: Resources
Antibodies Sentences Resources Expression of ACE-2: Cells diluted to 1 × 106 per microtiter plate well were incubated for 45 min at room temperature with a 1 in 100 dilution of a mouse IgG2a antibody to human/hamster ACE-2 (clone 171606 R&D Systems, Minneapolis, MN) mouse IgG2asuggested: (Millipore Cat# 171606-100UG, RRID:AB_10690063)In parallel the membrane was probed with a mouse monoclonal IgG antibody to ß-actin (Sc-47778, Santa Cruz Biotechnology, Dallas, TX) as a loading control for 1 hr at room temperature. ß-actinsuggested: (RayBiotech Cat# 168-10656, RRID:AB_2885189)Sc-47778suggested: NoneThe loading control antibody was probed with HRP-conjugated goat anti-mouse secondary IgG (SAB3701047, Sigma, St. Louis, MO) for 1 hr at room temperature. anti-mouse secondary IgGsuggested: NoneAn alkaline-phosphate-conjugated goat anti-mouse IgG antibody (Sigma-Aldrich, St Louis, MO) diluted to 1:1500 in 3%BAS-PBS was added at 60 μl/well for 1 hr at room temperature. An alkaline-phosphate-conjugated goat anti-mouse IgG antibodysuggested: Noneanti-mouse IgGsuggested: NoneACE binding inhibition assay: Sera were tested for inhibition of ACE binding to the RBD of S by the Anti-SARS-CoV-2 Neutralizing Antibody Titer Serologic Assay Kit from Acro Biosystems (Newark, DE) following the manufacturer’s instructions. Anti-SARS-CoV-2suggested: NoneA positive standard with a known concentration provided by the kit was used to extrapolated anti-S antibody concentrations in μg in the mouse sera. anti-Ssuggested: NoneExperimental Models: Cell Lines Sentences Resources Cell lines: HEK 293 cells and VeroE6 cells were grown in Dulbecco’s Modified Eagles medium (DMEM) supplemented with 10% fetal bovine serum (FBS) and antibiotics in a 5% CO2 incubator. HEK 293suggested: NoneVeroE6suggested: JCRB Cat# JCRB1819, RRID:CVCL_YQ49)66 BHK-21/WI-2 cells were plated into a 6 well plate, the next day cells were first transfected with 1 μg/well of the paT7 plasmids using polyethyleneimine (PEI) (Polysciences, Inc. Warrington, PA); 2 hours later, the cells were treated with a predetermined optimal amount of ΔG-GFP (G*ΔG-GFP) rVSV. BHK-21/WI-2suggested: RRID:CVCL_HB78)Experimental Models: Organisms/Strains Sentences Resources Mice and mouse procedures: Female C57Bl/6 mice (6–8 weeks of age) were purchased from the Jackson Laboratories (Bar Harbor, ME). C57Bl/6suggested: NoneRecombinant DNA Sentences Resources 66 BHK-21/WI-2 cells were plated into a 6 well plate, the next day cells were first transfected with 1 μg/well of the paT7 plasmids using polyethyleneimine (PEI) (Polysciences, Inc. Warrington, PA); 2 hours later, the cells were treated with a predetermined optimal amount of ΔG-GFP (G*ΔG-GFP) rVSV. paT7suggested: NoneVNA assay with VSV-S: VSV-S vectors was initially titrated on BHK-21/WI-2 cells. VSV-Ssuggested: NoneResults 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: We detected the following sentences addressing limitations in the study:VNAs to the vaccine vectors will likely pose limitations to repeated booster immunization using the same Ad vector by not only reducing, but also, as we reported previously, modifying transgene product-specific immune responses.56 To avoid interference by Ad vector-specific VNAs, we developed a vaccine regimen composed of two serologically distinct E1-deleted AdC vectors. We selected AdC vectors as pre-existing VNAs to these chimpanzee viruses are rare in humans and individuals who have VNAs in general have low titers.44 We developed two serologically distinct AdC vectors to prevent blunting of booster immunizations by VNAs induced by the AdC vector used for priming. The two AdC vectors express the S protein of an isolate from Sweden, which is identical to that of the original Wuhan virus. We did not codon-optimize the S sequence, nor did we incorporate the K986P and V987P stabilizing mutations into the S2 sequence which both were used for the S gene expressed by the RNA vaccines,57 mutations of the S1/S2 furin cleavage site which, in addition to the stabilizing mutations, were incorporated into the S gene carried by the J&J COVID-19 vaccine,58 or AstraZeneca’s engineered leader sequence.59 Phase III trial results of the different Ad vector vaccines fail to indicate that any of these modifications have a major impact on vaccine efficacy. In our study, as expected, the magnitude of S protein-specific antibody responses after a single immunization increased with higher vaccine ...
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.
Results from scite Reference Check: We found no unreliable references.
-