Due to the fast global spreading of the Severe Acute Respiratory Syndrome Coronavirus - 2 (SARS-CoV-2), prevention and treatment options are direly needed in order to control infection-related morbidity, mortality, and economic losses. Although drug and inactivated and attenuated virus vaccine development can require significant amounts of time and resources, DNA and RNA vaccines offer a quick, simple, and cheap treatment alternative, even when produced on a large scale. The spike protein, which has been shown as the most antigenic SARS-CoV-2 protein, has been widely selected as the target of choice for DNA/RNA vaccines. Vaccination campaigns have reported high vaccination rates and protection, but numerous unintended effects, ranging from muscle pain to death, have led to concerns about the safety of RNA/DNA vaccines. In parallel to these studies, several open reading frames (ORFs) have been found to be overlapping SARS-CoV-2 accessory genes, two of which, ORF2b and ORF-Sh, overlap the spike protein sequence. Thus, the presence of these, and potentially other ORFs on SARS-CoV-2 DNA/RNA vaccines, could lead to the translation of undesired proteins during vaccination. Herein, we discuss the translation of overlapping genes in connection with DNA/RNA vaccines. Two mRNA vaccine spike protein sequences, which have been made publicly-available, were compared to the wild-type sequence in order to uncover possible differences in putative overlapping ORFs. Notably, the Moderna mRNA-1273 vaccine sequence is predicted to contain no frameshifted ORFs on the positive sense strand, which highlights the utility of codon optimization in DNA/RNA vaccine design to remove undesired overlapping ORFs. Since little information is available on ORF2b or ORF-Sh, we use structural bioinformatics techniques to investigate the structure-function relationship of these proteins. The presence of putative ORFs on DNA/RNA vaccine candidates implies that overlapping genes may contribute to the translation of smaller peptides, potentially leading to unintended clinical outcomes, and that the protein-coding potential of DNA/RNA vaccines should be rigorously examined prior to administration.

Department of Biochemistry Sanger Building University of Cambridge Cambridge United Kingdom

Department of Biology and Ecology University of Ostrava Ostrava Czechia

Department of Physics University of Ostrava Ostrava Czechia

Zobrazit více v PubMed

Wu F, Zhao S, Yu B, Chen Y-M, Wang W, Song Z-G, et al. . A New Coronavirus Associated With Human Respiratory Disease in China. Nature (2020) 579:265–9. doi: 10.1038/s41586-020-2008-3 PubMed DOI PMC

Cevik M, Kuppalli K, Kindrachuk J, Peiris M. Virology, Transmission, and Pathogenesis of SARS-CoV-2. BMJ (2020) 371:m3862. doi: 10.1136/bmj.m3862 PubMed DOI

Cucinotta D, Vanelli M. WHO Declares COVID-19 a Pandemic. Acta BioMed (2020) 91:157–60. doi: 10.23750/abm.v91i1.9397 PubMed DOI PMC

Gorain B, Choudhury H, Molugulu N, Athawale RB, Kesharwani P. Fighting Strategies Against the Novel Coronavirus Pandemic: Impact on Global Economy. Front Public Heal (2020) 8:606129. doi: 10.3389/fpubh.2020.606129 PubMed DOI PMC

Pronker ES, Weenen TC, Commandeur H, Claassen EHJHM, Osterhaus ADME. Risk in Vaccine Research and Development Quantified. PloS One (2013) 8:e57755. doi: 10.1371/journal.pone.0057755 PubMed DOI PMC

Scannell JW, Blanckley A, Boldon H, Warrington B. Diagnosing the Decline in Pharmaceutical R&D Efficiency. Nat Rev Drug Discov (2012) 11:191–200. doi: 10.1038/nrd3681 PubMed DOI

Brisse M, Vrba SM, Kirk N, Liang Y, Ly H. Emerging Concepts and Technologies in Vaccine Development. Front Immunol (2020) 11:583077. doi: 10.3389/fimmu.2020.583077 PubMed DOI PMC

Nelson CW, Ardern Z, Goldberg TL, Meng C, Kuo C-H, Ludwig C, et al. . Dynamically Evolving Novel Overlapping Gene as a Factor in the SARS-CoV-2 Pandemic. Elife (2020) 9:e59633. doi: 10.7554/eLife.59633 PubMed DOI PMC

Finkel Y, Mizrahi O, Nachshon A, Weingarten-Gabbay S, Morgenstern D, Yahalom-Ronen Y, et al. . The Coding Capacity of SARS-CoV-2. Nature (2021) 589:125–30. doi: 10.1038/s41586-020-2739-1 PubMed DOI

Davidson AD, Williamson MK, Lewis S, Shoemark D, Carroll MW, Heesom KJ, et al. . Characterisation of the Transcriptome and Proteome of SARS-CoV-2 Reveals a Cell Passage Induced in-Frame Deletion of the Furin-Like Cleavage Site From the Spike Glycoprotein. Genome Med (2020) 12:68. doi: 10.1186/s13073-020-00763-0 PubMed DOI PMC

Lan J, Ge J, Yu J, Shan S, Zhou H, Fan S, et al. . Structure of the SARS-CoV-2 Spike Receptor-Binding Domain Bound to the ACE2 Receptor. Nature (2020) 581:215–20. doi: 10.1038/s41586-020-2180-5 PubMed DOI

Dandan L, Jinming L, Suzanne KC. Immunologic Testing for SARS-CoV-2 Infection From the Antigen Perspective. J Clin Microbiol (2021) 59:e02160-20. doi: 10.1128/JCM.02160-20 PubMed DOI PMC

Grant OC, Montgomery D, Ito K, Woods RJ. Analysis of the SARS-CoV-2 Spike Protein Glycan Shield Reveals Implications for Immune Recognition. Sci Rep (2020) 10:14991. doi: 10.1038/s41598-020-71748-7 PubMed DOI PMC

Watanabe Y, Allen JD, Wrapp D, McLellan JS, Crispin M. Site-Specific Glycan Analysis of the SARS-CoV-2 Spike. Science (2020) 369:330–3. doi: 10.1126/science.abb9983 PubMed DOI PMC

Samrat SK, Tharappel AM, Li Z, Li H. Prospect of SARS-CoV-2 Spike Protein: Potential Role in Vaccine and Therapeutic Development. Virus Res (2020) 288:198141. doi: 10.1016/j.virusres.2020.198141 PubMed DOI PMC

Wang J, Peng Y, Xu H, Cui Z. Williams RO 3rd. The COVID-19 Vaccine Race: Challenges and Opportunities in Vaccine Formulation. AAPS PharmSciTech (2020) 21:225. doi: 10.1208/s12249-020-01744-7 PubMed DOI PMC

Peletta A, Prompetchara E, Tharakhet K, Kaewpang P, Buranapraditkun S, Techawiwattanaboon T, et al. . DNA Vaccine Administered by Cationic Lipoplexes or by In Vivo Electroporation Induces Comparable Antibody Responses Against SARS-CoV-2 in Mice. Vaccines (2021) 9:874. doi: 10.3390/vaccines9080874 PubMed DOI PMC

Rijkers GT, Weterings N, Obregon-Henao A, Lepolder M, Dutt TS, van Overveld FJ, et al. . Antigen Presentation of mRNA-Based and Virus-Vectored SARS-CoV-2 Vaccines. Vaccines (2021) 9:848. doi: 10.3390/vaccines9080848 PubMed DOI PMC

Heinz FX, Stiasny K. Distinguishing Features of Current COVID-19 Vaccines: Knowns and Unknowns of Antigen Presentation and Modes of Action. NPJ Vaccines (2021) 6:104. doi: 10.1038/s41541-021-00369-6 PubMed DOI PMC

Park JW, Lagniton PNP, Liu Y, Xu R-H. mRNA Vaccines for COVID-19: What, Why and How. Int J Biol Sci (2021) 17:1446–60. doi: 10.7150/ijbs.59233 PubMed DOI PMC

Chung H, He S, Nasreen S, Sundaram ME, Buchan SA, Wilson SE, et al. . Effectiveness of BNT162b2 and mRNA-1273 Covid-19 Vaccines Against Symptomatic SARS-CoV-2 Infection and Severe Covid-19 Outcomes in Ontario, Canada: Test Negative Design Study. BMJ (2021) 374:n1943. doi: 10.1136/bmj.n1943 PubMed DOI PMC

Pritchard E, Matthews PC, Stoesser N, Eyre DW, Gethings O, Vihta K-D, et al. . Impact of Vaccination on New SARS-CoV-2 Infections in the United Kingdom. Nat Med (2021) 27:1370–8. doi: 10.1038/s41591-021-01410-w PubMed DOI PMC

Wibmer CK, Ayres F, Hermanus T. SARS-CoV-2 501Y.V2 Escapes Neutralization By South African COVID-19 Donor Plasma. Nat Med (2021) 27:622–5. PubMed

Hosseini SA, Zahedipour F, Mirzaei H, Kazemi Oskuee R. Potential SARS-CoV-2 Vaccines: Concept, Progress, and Challenges. Int Immunopharmacol (2021) 97:107622. doi: 10.1016/j.intimp.2021.107622 PubMed DOI PMC

FDA Approves First COVID-19 Vaccine (2021). Available at: https://www.fda.gov/news-events/press-announcements/fda-approves-first-covid-19-vaccine (Accessed September 17, 2021).

Chakraborty S, Mallajosyula V, Tato CM, Tan GS, Wang TT. SARS-CoV-2 Vaccines in Advanced Clinical Trials: Where Do We Stand? Adv Drug Deliv Rev (2021) 172:314–38. doi: 10.1016/j.addr.2021.01.014 PubMed DOI PMC

Menni C, Klaser K, May A, Polidori L, Capdevila J, Louca P, et al. . Vaccine Side-Effects and SARS-CoV-2 Infection After Vaccination in Users of the COVID Symptom Study App in the UK: A Prospective Observational Study. Lancet Infect Dis (2021) 21:939–49. doi: 10.1016/S1473-3099(21)00224-3 PubMed DOI PMC

Lv G, Yuan J, Xiong X, Li M. Mortality Rate and Characteristics of Deaths Following COVID-19 Vaccination. Front Med (2021) 8:670370. doi: 10.3389/fmed.2021.670370 PubMed DOI PMC

Karayeva E, Kim HW, Bandy U, Clyne A, Marak TP. Monitoring Vaccine Adverse Event Reporting System (VAERS) Reports Related to COVID-19 Vaccination Efforts in Rhode Island. R I Med J (2013) (2021) 104:64–6. PubMed

Deb A, Abdelmalek J, Iwuji K, Nugent K. Acute Myocardial Injury Following COVID-19 Vaccination: A Case Report and Review of Current Evidence From Vaccine Adverse Events Reporting System Database. J Prim Care Commun Health (2021) 12:21501327211029230. doi: 10.1177/21501327211029230 PubMed DOI PMC

Sharifian-Dorche M, Bahmanyar M, Sharifian-Dorche A, Mohammadi P, Nomovi M, Mowla A. Vaccine-Induced Immune Thrombotic Thrombocytopenia and Cerebral Venous Sinus Thrombosis Post COVID-19 Vaccination; a Systematic Review. J Neurol Sci (2021) 428:117607. doi: 10.1016/j.jns.2021.117607 PubMed DOI PMC

Martinez-Marmol R, Giordano-Santini R, Kaulich E, Cho A-N, Riyadh MA, Robinson E, et al. . The SARS-CoV-2 Spike (S) and the Orthoreovirus P15 Cause Neuronal and Glial Fusion. bioRxiv (2021), 2021.09.01.458544. doi: 10.1101/2021.09.01.458544 DOI

Buzhdygan TP, DeOre BJ, Baldwin-Leclair A, Bullock TA, McGary HM, Khan JA, et al. . The SARS-CoV-2 Spike Protein Alters Barrier Function in 2D Static and 3D Microfluidic In-Vitro Models of the Human Blood–Brain Barrier. Neurobiol Dis (2020) 146:105131. doi: 10.1016/j.nbd.2020.105131 PubMed DOI PMC

Olajide OA, Iwuanyanwu VU, Adegbola OD, Al-Hindawi AA. SARS-CoV-2 Spike Glycoprotein S1 Induces Neuroinflammation in BV-2 Microglia. bioRxiv (2021), 2020.12.29.424619. doi: 10.1101/2020.12.29.424619 PubMed DOI PMC

Keith M, Tapas P, Vijayamahantesh, Ranjit R, Tom G. SARS-CoV-2 Spike Protein Induces Paracrine Senescence and Leukocyte Adhesion in Endothelial Cells. J Virol (2021) 95:e00794-21. doi: 10.1128/JVI.00794-21 PubMed DOI PMC

Orr MW, Mao Y, Storz G, Qian S-B. Alternative ORFs and Small ORFs: Shedding Light on the Dark Proteome. Nucleic Acids Res (2020) 48:1029–42. doi: 10.1093/nar/gkz734 PubMed DOI PMC

Calviello L, Hirsekorn A, Ohler U. Quantification of Translation Uncovers the Functions of the Alternative Transcriptome. Nat Struct Mol Biol (2020) 27:717–25. doi: 10.1038/s41594-020-0450-4 PubMed DOI

Huang J-Z, Chen M, Chen D, Gao X-C, Zhu S, Huang H, et al. . A Peptide Encoded by a Putative lncRNA HOXB-AS3 Suppresses Colon Cancer Growth. Mol Cell (2017) 68:171–84.e6. doi: 10.1016/j.molcel.2017.09.015 PubMed DOI

Anderson DM, Anderson KM, Chang C-L, Makarewich CA, Nelson BR, McAnally JR, et al. . A Micropeptide Encoded by a Putative Long Noncoding RNA Regulates Muscle Performance. Cell (2015) 160:595–606. doi: 10.1016/j.cell.2015.01.009 PubMed DOI PMC

Dinman JD. Mechanisms and Implications of Programmed Translational Frameshifting. WIREs RNA (2012) 3:661–73. doi: 10.1002/wrna.1126 PubMed DOI PMC

Bazykin GA, Kochetov AV. Alternative Translation Start Sites Are Conserved in Eukaryotic Genomes. Nucleic Acids Res (2011) 39:567–77. doi: 10.1093/nar/gkq806 PubMed DOI PMC

Yang Y, Wang Z. IRES-Mediated Cap-Independent Translation, a Path Leading to Hidden Proteome. J Mol Cell Biol (2019) 11:911–9. doi: 10.1093/jmcb/mjz091 PubMed DOI PMC

Chirico N, Vianelli A, Belshaw R. Why Genes Overlap in Viruses. Proc Biol Sci (2010) 277:3809–17. doi: 10.1098/rspb.2010.1052 PubMed DOI PMC

Pavesi A. Origin, Evolution and Stability of Overlapping Genes in Viruses: A Systematic Review. Genes (Basel) (2021) 12:809. doi: 10.3390/genes12060809 PubMed DOI PMC

Michel CJ, Mayer C, Poch O, Thompson JD. Characterization of Accessory Genes in Coronavirus Genomes. Virol J (2020) 17:131. doi: 10.1186/s12985-020-01402-1 PubMed DOI PMC

Weingarten-Gabbay S, Klaeger S, Sarkizova S, Pearlman LR, Chen DY, Gallagher KM, et al. . Profiling SARS-CoV-2 HLA-I Peptidome Reveals T Cell Epitopes From Out-of- Frame ORFs. Cell (2021) 184(15):3962–80. PubMed PMC

Pavesi A. Prediction of Two Novel Overlapping ORFs in the Genome of SARS-CoV-2. Virology (2021) 562:149–57. doi: 10.1016/j.virol.2021.07.011 PubMed DOI PMC

Jungreis I, Sealfon R, Kellis M. SARS-CoV-2 Gene Content and COVID-19 Mutation Impact by Comparing 44 Sarbecovirus Genomes. Nat Commun (2021) 12:2642. doi: 10.1038/s41467-021-22905-7 PubMed DOI PMC

Aoki A, Adachi H, Mori Y, Ito M, Sato K, Okuda K, et al. . A Rapid Screening Assay for L452R and T478K Spike Mutations in SARS-CoV-2 Delta Variant Using High-Resolution Melting Analysis. J Toxicol Sci (2021) 46:471–6. doi: 10.2131/jts.46.471 PubMed DOI

Gordon DE, Jang GM, Bouhaddou M, Xu J, Obernier K, White KM, et al. . A SARS-CoV-2 Protein Interaction Map Reveals Targets for Drug Repurposing. Nature (2020) 583:459–68. doi: 10.1038/s41586-020-2286-9 PubMed DOI PMC

Dominguez Andres A, Feng Y, Campos AR, Yin J, Yang C-C, James B, et al. . SARS-CoV-2 ORF9c Is a Membrane-Associated Protein That Suppresses Antiviral Responses in Cells. bioRxiv (2020), 2020.08.18.256776. doi: 10.1101/2020.08.18.256776 DOI

Alsulami AF, Thomas SE, Jamasb AR, Beaudoin CA, Moghul I, Bannerman B, et al. . SARS-CoV-2 3D Database: Understanding the Coronavirus Proteome and Evaluating Possible Drug Targets. Brief Bioinform (2021) 22:769–80. doi: 10.1093/bib/bbaa404 PubMed DOI PMC

Beaudoin CA, Jamasb AR, Alsulami AF, Copoiu L, van Tonder AJ, Hala S, et al. . Predicted Structural Mimicry of Spike Receptor-Binding Motifs From Highly Pathogenic Human Coronaviruses. Comput Struct Biotechnol J (2021) 19:3938–53. doi: 10.1016/j.csbj.2021.06.041 PubMed DOI PMC

Šali A, Blundell TL. Comparative Protein Modelling by Satisfaction of Spatial Restraints. J Mol Biol (1993) 234:779–815. doi: 10.1006/jmbi.1993.1626 PubMed DOI

Wang S, Li W, Liu S, Xu J. RaptorX-Property: A Web Server for Protein Structure Property Prediction. Nucleic Acids Res (2016) 44:W430–5. doi: 10.1093/nar/gkw306 PubMed DOI PMC

Wang S, Ma J, Xu J. AUCpreD: Proteome-Level Protein Disorder Prediction by AUC-Maximized Deep Convolutional Neural Fields. Bioinformatics (2016) 32:i672–9. doi: 10.1093/bioinformatics/btw446 PubMed DOI PMC

Yang J, Anishchenko I, Park H, Peng Z, Ovchinnikov S, Baker D. Improved Protein Structure Prediction Using Predicted Interresidue Orientations. Proc Natl Acad Sci (2020) 117:1496–503. doi: 10.1073/pnas.1914677117 PubMed DOI PMC

Bartas M, Volná A, Beaudoin CA, Poulsen ET, Červeň J, Brázda V, et al. . Unheeded SARS-CoV-2 Proteins? A Deep Look Into Negative-Sense RNA. bioRxiv (2021), 2020.11.27.400788. doi: 10.1101/2020.11.27.400788 PubMed DOI PMC

Gabler F, Nam S-Z, Till S, Mirdita M, Steinegger M, Söding J, et al. . Protein Sequence Analysis Using the MPI Bioinformatics Toolkit. Curr Protoc Bioinforma (2020) 72:e108. doi: 10.1002/cpbi.108 PubMed DOI

Lu S, Wang J, Chitsaz F, Derbyshire MK, Geer RC, Gonzales NR, et al. . CDD/SPARCLE: The Conserved Domain Database in 2020. Nucleic Acids Res (2020) 48:D265–8. doi: 10.1093/nar/gkz991 PubMed DOI PMC

Krogh A, Larsson B, von Heijne G, Sonnhammer EL. Predicting Transmembrane Protein Topology With a Hidden Markov Model: Application to Complete Genomes. J Mol Biol (2001) 305:567–80. doi: 10.1006/jmbi.2000.4315 PubMed DOI

Ayoub R, Lee Y. Rupee: A Fast and Accurate Purely Geometric Protein Structure Search. PloS One (2019) 14:1–17. doi: 10.1371/journal.pone.0213712 PubMed DOI PMC

McClenaghan C, Hanson A, Lee S-J, Nichols CG. Coronavirus Proteins as Ion Channels: Current and Potential Research. Front Immunol (2020) 11:573339. doi: 10.3389/fimmu.2020.573339 PubMed DOI PMC

Cagliani R, Forni D, Clerici M, Sironi M. Coding Potential and Sequence Conservation of SARS-CoV-2 and Related Animal Viruses. Infect Genet Evol (2020) 83:104353. doi: 10.1016/j.meegid.2020.104353 PubMed DOI PMC

Peisach E, Pabo CO. Constraints for Zinc Finger Linker Design as Inferred From X-Ray Crystal Structure of Tandem Zif268–DNA Complexes. J Mol Biol (2003) 330:1–7. doi: 10.1016/S0022-2836(03)00572-2 PubMed DOI

Mauro VP, Chappell SA. A Critical Analysis of Codon Optimization in Human Therapeutics. Trends Mol Med (2014) 20:604–13. doi: 10.1016/j.molmed.2014.09.003 PubMed DOI PMC

Madeira F, Park YM, Lee J, Buso N, Gur T, Madhusoodanan N, et al. . The EMBL-EBI Search and Sequence Analysis Tools APIs in 2019. Nucleic Acids Res (2019) 47:W636–41. doi: 10.1093/nar/gkz268 PubMed DOI PMC

Bourret J, Alizon S, Bravo IG. COUSIN (COdon Usage Similarity INdex): A Normalized Measure of Codon Usage Preferences. Genome Biol Evol (2019) 11:3523–8. doi: 10.1093/gbe/evz262 PubMed DOI PMC

Puigbò P, Bravo IG, Garcia-Vallve S. CAIcal: A Combined Set of Tools to Assess Codon Usage Adaptation. Biol Direct (2008) 3:38. doi: 10.1186/1745-6150-3-38 PubMed DOI PMC

Sharp PM, Li WH. The Codon Adaptation Index–a Measure of Directional Synonymous Codon Usage Bias, and its Potential Applications. Nucleic Acids Res (1987) 15:1281–95. doi: 10.1093/nar/15.3.1281 PubMed DOI PMC

Li Y, Yang X, Wang N, Wang H, Yin B, Yang X, et al. . GC Usage of SARS-CoV-2 Genes Might Adapt to the Environment of Human Lung Expressed Genes. Mol Genet Genomics (2020) 295:1537–46. doi: 10.1007/s00438-020-01719-0 PubMed DOI PMC

Dilucca M, Forcelloni S, Georgakilas AG, Giansanti A, Pavlopoulou A. Codon Usage and Phenotypic Divergences of SARS-CoV-2 Genes. Viruses (2020) 12:498. doi: 10.3390/v12050498 PubMed DOI PMC

Smith TRF, Patel A, Ramos S, Elwood D, Zhu X, Yan J, et al. . Immunogenicity of a DNA Vaccine Candidate for COVID-19. Nat Commun (2020) 11:2601. doi: 10.1038/s41467-020-16505-0 PubMed DOI PMC

Walsh EE, Frenck RW, Jr., Falsey AR, Kitchin N, Absalon J, Gurtman A, et al. . Safety and Immunogenicity of Two RNA-Based Covid-19 Vaccine Candidates. N Engl J Med (2020) 383:2439–50. doi: 10.1056/NEJMoa2027906 PubMed DOI PMC

Aebischer A, Wernike K, König P, Franzke K, Wichgers Schreur PJ, Kortekaas J, et al. . Development of a Modular Vaccine Platform for Multimeric Antigen Display Using an Orthobunyavirus Model. Vaccines (2021) 9:651. doi: 10.3390/vaccines9060651 PubMed DOI PMC

Denis J, Majeau N, Acosta-Ramirez E, Savard C, Bedard M-C, Simard S, et al. . Immunogenicity of Papaya Mosaic Virus-Like Particles Fused to a Hepatitis C Virus Epitope: Evidence for the Critical Function of Multimerization. Virology (2007) 363:59–68. doi: 10.1016/j.virol.2007.01.011 PubMed DOI

Sahin U, Oehm P, Derhovanessian E, Jabulowsky RA, Vormehr M, Gold M, et al. . An RNA Vaccine Drives Immunity in Checkpoint-Inhibitor-Treated Melanoma. Nature (2020) 585:107–12. doi: 10.1038/s41586-020-2537-9 PubMed DOI

Trovato M, Maurano F, D’Apice L, Costa V, Sartorius R, Cuccaro F, et al. . E2 Multimeric Scaffold for Vaccine Formulation: Immune Response by Intranasal Delivery and Transcriptome Profile of E2-Pulsed Dendritic Cells. BMC Microbiol (2016) 16:152. doi: 10.1186/s12866-016-0772-x PubMed DOI PMC

Yi C, Sun X, Ye J, Ding L, Liu M, Yang Z, et al. . Key Residues of the Receptor Binding Motif in the Spike Protein of SARS-CoV-2 That Interact With ACE2 and Neutralizing Antibodies. Cell Mol Immunol (2020) 17:621–30. doi: 10.1038/s41423-020-0458-z PubMed DOI PMC

Forni G, Mantovani A, Forni G, Mantovani A, Moretta L, Rappuoli R, et al. . COVID-19 Vaccines: Where We Stand and Challenges Ahead. Cell Death Differ (2021) 28:626–39. doi: 10.1038/s41418-020-00720-9 PubMed DOI PMC

Gonçalves E, Guillén Y, Lama JR, Sanchez J, Brander C, Paredes R, et al. . Host Transcriptome and Microbiota Signatures Prior to Immunization Profile Vaccine Humoral Responsiveness. Front Immunol (2021) 12:657162. doi: 10.3389/fimmu.2021.657162 PubMed DOI PMC