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1.
Int J Mol Sci ; 23(21)2022 Oct 30.
Article in English | MEDLINE | ID: covidwho-2090212

ABSTRACT

Mutations in surface proteins enable emerging variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to escape a substantial fraction of neutralizing antibodies and may thus weaken vaccine-driven immunity. To compare available vaccines and justify revaccination, rapid evaluation of antibody (Ab) responses to currently circulating SARS-CoV-2 variants of interest (VOI) and concern (VOC) is needed. Here, we developed a multiplex protein microarray-based system for rapid profiling of anti-SARS-CoV-2 Ab levels in human sera. The microarray system was validated using sera samples from SARS-CoV-2-free donors and those diagnosed with COVID-19 based on PCR and enzyme immunoassays. Microarray-based profiling of vaccinated donors revealed a substantial difference in anti-VOC Ab levels elicited by the replication-deficient adenovirus vector-base (Sputnik V) and whole-virion (CoviVac Russia COVID-19) vaccines. Whole-virion vaccine-induced Abs showed minor but statistically significant cross-reactivity with the human blood coagulation factor 1 (fibrinogen) and thrombin. However, their effects on blood clotting were negligible, according to thrombin time tests, providing evidence against the concept of pronounced cross-reactivity-related side effects of the vaccine. Importantly, all samples were collected in the pre-Omicron period but showed noticeable responses to the receptor-binding domain (RBD) of the Omicron spike protein. Thus, using the new express Ab-profiling system, we confirmed the inter-variant cross-reactivity of the anti-SARS-CoV-2 Abs and demonstrated the relative potency of the vaccines against new VOCs.


Subject(s)
Antibody Formation , COVID-19 Vaccines , Humans , Antibodies, Neutralizing , Antibodies, Viral , Antibody Formation/genetics , COVID-19/prevention & control , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/genetics , Vaccination , Viral Vaccines/genetics , Viral Vaccines/pharmacology , COVID-19 Vaccines/genetics , COVID-19 Vaccines/pharmacology , Microarray Analysis
2.
ESMO Open ; 7(5): 100574, 2022 10.
Article in English | MEDLINE | ID: covidwho-2036006

ABSTRACT

BACKGROUND: The role and the durability of the immunogenicity of the third dose of vaccine against COVID-19 variants of concern in cancer patients have to be elucidated. PATIENTS AND METHODS: We have prospectively evaluated the immunogenicity of the third dose of the SARS-CoV-2 BNT162b2 messenger RNA vaccine in triggering both humoral and cell-mediated immune response in patients with solid tumors undergoing active treatment 6 months after the booster. Neutralizing antibody (NT Ab) titers and total anti-spike immunoglobulin G concentrations were measured in serum. Heparinized whole blood samples were used for the SARS-CoV-2 interferon-γ release assay (IGRA). RESULTS: Six months after the third dose only two patients (2.4%) showed negative spike-specific immunoglobulin G antibody levels (<33.8 BAU/ml). The median level of SARS-CoV-2 NT Abs decreased and only 39/83 (47%) subjects showed maximum levels of NT Abs. T-cellular positive response was observed in 38/61 (62.3%) patients; the highest median level of response was observed 21 days after the third dose (354 mIU/ml, interquartile range 83.3-846.3 mIU/ml). The lowest median level of NT Ab response was observed against the Omicron variant (1 : 10, interquartile range 1 : 10-1 : 40) with a significant reduced rate of responder subjects with respect to the wild-type strain (77.5% versus 95%; P = 0.0022) and Delta variant (77.5% versus 93.7%; P = 0.0053). During the follow-up period, seven patients (8%) had a confirmed post-vaccination infection, but none of them required hospitalization or oxygen therapy. CONCLUSIONS: Our work highlights a significant humoral and cellular immune response among patients with solid tumors 6 months after the third BNT162b2 vaccine dose, although a reduction in neutralizing activity against Omicron was observed.


Subject(s)
COVID-19 , Neoplasms , Viral Vaccines , Humans , COVID-19 Vaccines/pharmacology , BNT162 Vaccine , Longitudinal Studies , Antibodies, Viral , Viral Vaccines/genetics , SARS-CoV-2 , COVID-19/prevention & control , Antibodies, Neutralizing , Immunoglobulin G , Immunity, Cellular , Neoplasms/drug therapy , Oxygen
3.
PLoS One ; 17(3): e0264994, 2022.
Article in English | MEDLINE | ID: covidwho-1938426

ABSTRACT

COVID-19 severely impacted world health and, as a consequence of the measures implemented to stop the spread of the virus, also irreversibly damaged the world economy. Research shows that receiving the COVID-19 vaccine is the most successful measure to combat the virus and could also address its indirect consequences. However, vaccine hesitancy is growing worldwide and the WHO names this hesitancy as one of the top ten threats to global health. This study investigates the trend in positive attitudes towards vaccines across ten countries since a positive attitude is important. Furthermore, we investigate those variables related to having a positive attitude, as these factors could potentially increase the uptake of vaccines. We derive our text corpus from vaccine-related tweets, harvested in real-time from Twitter. Using Natural Language Processing (NLP), we derive the sentiment and emotions contained in the tweets to construct daily time-series data. We analyse a panel dataset spanning both the Northern and Southern hemispheres from 1 February 2021 to 31 July 2021. To determine the relationship between several variables and the positive sentiment (attitude) towards vaccines, we run various models, including POLS, Panel Fixed Effects and Instrumental Variables estimations. Our results show that more information about vaccines' safety and the expected side effects are needed to increase positive attitudes towards vaccines. Additionally, government procurement and the vaccine rollout should improve. Accessibility to the vaccine should be a priority, and a collective effort should be made to increase positive messaging about the vaccine, especially on social media. The results of this study contribute to the understanding of the emotional challenges associated with vaccine uptake and inform policymakers, health workers, and stakeholders who communicate to the public during infectious disease outbreaks. Additionally, the global fight against COVID-19 might be lost if the attitude towards vaccines is not improved.


Subject(s)
COVID-19/psychology , Vaccination/psychology , Attitude , COVID-19 Vaccines/pharmacology , Emotions , Global Health , Humans , Models, Theoretical , Natural Language Processing , Optimism , SARS-CoV-2/pathogenicity , Social Media , Vaccination/statistics & numerical data , Vaccination/trends , /trends , Vaccines
5.
Br J Haematol ; 198(4): 668-679, 2022 08.
Article in English | MEDLINE | ID: covidwho-1874397

ABSTRACT

Allogeneic haematopoietic stem cell transplant (HSCT) recipients remain at high risk of adverse outcomes from coronavirus disease 2019 (COVID-19) and emerging variants. The optimal prophylactic vaccine strategy for this cohort is not defined. T cell-mediated immunity is a critical component of graft-versus-tumour effect and in determining vaccine immunogenicity. Using validated anti-spike (S) immunoglobulin G (IgG) and S-specific interferon-gamma enzyme-linked immunospot (IFNγ-ELIspot) assays we analysed response to a two-dose vaccination schedule (either BNT162b2 or ChAdOx1) in 33 HSCT recipients at ≤2 years from transplant, alongside vaccine-matched healthy controls (HCs). After two vaccines, infection-naïve HSCT recipients had a significantly lower rate of seroconversion compared to infection-naïve HCs (25/32 HSCT vs. 39/39 HCs no responders) and had lower S-specific T-cell responses. The HSCT recipients who received BNT162b2 had a higher rate of seroconversion compared to ChAdOx1 (89% vs. 74%) and significantly higher anti-S IgG titres (p = 0.022). S-specific T-cell responses were seen after one vaccine in HCs and HSCT recipients. However, two vaccines enhanced S-specific T-cell responses in HCs but not in the majority of HSCT recipients. These data demonstrate limited immunogenicity of two-dose vaccination strategies in HSCT recipients, bolstering evidence of the need for additional boosters and/or alternative prophylactic measures in this group.


Subject(s)
COVID-19 Vaccines , COVID-19 , Hematopoietic Stem Cell Transplantation , Age Factors , Antibodies, Viral/immunology , BNT162 Vaccine/immunology , BNT162 Vaccine/therapeutic use , Bone Marrow Transplantation/adverse effects , COVID-19/prevention & control , COVID-19/virology , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , COVID-19 Vaccines/pharmacology , COVID-19 Vaccines/therapeutic use , ChAdOx1 nCoV-19/immunology , ChAdOx1 nCoV-19/therapeutic use , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Immunity, Cellular/drug effects , Immunity, Cellular/immunology , Immunity, Humoral/drug effects , Immunity, Humoral/immunology , Immunoglobulin G/blood , Immunoglobulin G/immunology , Seroconversion , Transplantation, Homologous/adverse effects , Vaccination/adverse effects
6.
Int J Mol Sci ; 23(9)2022 Apr 28.
Article in English | MEDLINE | ID: covidwho-1820291

ABSTRACT

During the sustained COVID-19 pandemic, global mass vaccination to achieve herd immunity can prevent further viral spread and mutation. A protein subunit vaccine that is safe, effective, stable, has few storage restrictions, and involves a liable manufacturing process would be advantageous to distribute around the world. Here, we designed and produced a recombinant spike (S)-Trimer that is maintained in a prefusion state and exhibits a high ACE2 binding affinity. Rodents received different doses of S-Trimer (0.5, 5, or 20 µg) antigen formulated with aluminum hydroxide (Alum) or an emulsion-type adjuvant (SWE), or no adjuvant. After two vaccinations, the antibody response, T-cell responses, and number of follicular helper T-cells (Tfh) or germinal center (GC) B cells were assessed in mice; the protective efficacy was evaluated on a Syrian hamster infection model. The mouse studies demonstrated that adjuvating the S-Trimer with SWE induced a potent humoral immune response and Th1-biased cellular immune responses (in low dose) that were superior to those induced by Alum. In the Syrian hamster studies, when S-Trimer was adjuvanted with SWE, higher levels of neutralizing antibodies were induced against live SARS-CoV-2 from the original lineage and against the emergence of variants (Beta or Delta) with a slightly decreased potency. In addition, the SWE adjuvant demonstrated a dose-sparing effect; thus, a lower dose of S-Trimer as an antigen (0.5 µg) can induce comparable antisera and provide complete protection from viral infection. These data support the utility of SWE as an adjuvant to enhance the immunogenicity of the S-Trimer vaccine, which is feasible for further clinical testing.


Subject(s)
COVID-19 Vaccines , COVID-19 , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Th1 Cells , Adjuvants, Immunologic/pharmacology , Adjuvants, Pharmaceutic , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines/pharmacology , Cricetinae , Emulsions , Humans , Mice , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/immunology , Th1 Cells/immunology
7.
Med (N Y) ; 3(5): 309-324.e6, 2022 05 13.
Article in English | MEDLINE | ID: covidwho-1796324

ABSTRACT

BACKGROUND: Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 2019, viral variants with greater transmissibility or immune-evasion properties have arisen, which could jeopardize recently deployed vaccine- and antibody-based countermeasures. METHODS: Here, we evaluated in mice and hamsters the efficacy of a pre-clinical version of the Moderna mRNA vaccine (mRNA-1273) and the Johnson & Johnson recombinant adenoviral-vectored vaccine (Ad26.COV2.S) against the B.1.621 (Mu) variant of SARS-CoV-2, which contains spike mutations T95I, Y144S, Y145N, R346K, E484K, N501Y, D614G, P681H, and D950N. FINDINGS: Immunization of 129S2 and K18-human ACE2 transgenic mice with the mRNA-1273 vaccine protected against weight loss, lung infection, and lung pathology after challenge with the B.1.621 or WA1/2020 N501Y/D614G SARS-CoV-2 strain. Similarly, immunization of 129S2 mice and Syrian hamsters with a high dose of Ad26.COV2.S reduced lung infection after B.1.621 virus challenge. CONCLUSIONS: Thus, immunity induced by the mRNA-1273 or Ad26.COV2.S vaccine can protect against the B.1.621 variant of SARS-CoV-2 in multiple animal models. FUNDING: This study was supported by the NIH (R01 AI157155 and U01 AI151810), NIAID Centers of Excellence for Influenza Research and Response [CEIRR] contracts 75N93021C00014 and 75N93021C00016, and the Collaborative Influenza Vaccine Innovation Centers [CIVIC] contract 75N93019C00051. It was also supported, in part, by the National Institutes of Allergy and Infectious Diseases Center for Research on Influenza Pathogenesis (HHSN272201400008C) and the Japan Program for Infectious Diseases Research and Infrastructure (JP21wm0125002) from the Japan Agency for Medical Research and Development (AMED).


Subject(s)
2019-nCoV Vaccine mRNA-1273 , COVID-19 , Influenza, Human , mRNA Vaccines , 2019-nCoV Vaccine mRNA-1273/immunology , 2019-nCoV Vaccine mRNA-1273/pharmacology , Ad26COVS1 , Animals , Antibodies, Neutralizing , COVID-19/immunology , COVID-19/prevention & control , COVID-19/virology , COVID-19 Vaccines/immunology , COVID-19 Vaccines/pharmacology , Cricetinae , Humans , Mice , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , mRNA Vaccines/immunology , mRNA Vaccines/pharmacology
8.
PLoS One ; 17(2): e0263155, 2022.
Article in English | MEDLINE | ID: covidwho-1793533

ABSTRACT

With limited availability of vaccines, an efficient use of the limited supply of vaccines in order to achieve herd immunity will be an important tool to combat the wide-spread prevalence of COVID-19. Here, we compare a selection of strategies for vaccine distribution, including a novel targeted vaccination approach (EHR) that provides a noticeable increase in vaccine impact on disease spread compared to age-prioritized and random selection vaccination schemes. Using high-fidelity individual-based computer simulations with Oslo, Norway as an example, we find that for a community reproductive number in a setting where the base pre-vaccination reproduction number R = 2.1 without population immunity, the EHR method reaches herd immunity at 48% of the population vaccinated with 90% efficiency, whereas the common age-prioritized approach needs 89%, and a population-wide random selection approach requires 61%. We find that age-based strategies have a substantially weaker impact on epidemic spread and struggle to achieve herd immunity under the majority of conditions. Furthermore, the vaccination of minors is essential to achieving herd immunity, even for ideal vaccines providing 100% protection.


Subject(s)
COVID-19 Vaccines/supply & distribution , COVID-19/prevention & control , COVID-19/genetics , COVID-19/immunology , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/pharmacology , Epidemics , Humans , Immunity, Herd/immunology , Models, Theoretical , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Vaccination , Vaccines
9.
PLoS One ; 17(2): e0263351, 2022.
Article in English | MEDLINE | ID: covidwho-1793531

ABSTRACT

Pandemics, such as the current SARS-CoV-2 pandemic, represents a health threat to humans worldwide. During times of heightened health risks, the public's perceptions, and acceptance of evidence-based preventive measures, such as vaccines, is of high relevance. Moreover, people might seek other preventive remedies to protect themselves from getting infected (e.g., herbal remedies, nutritional supplements). A recent study on consumers' preference for naturalness showed that people put more weight on perceived naturalness of a preventive remedy compared to a curative one. This result was attributed to the increased focus on perceived effectiveness as opposed to perceived risk. This raises the question whether the current pandemic would shift people's perceptions from prevention to curing and thus, exhibit a preference for synthetic remedies because they are seen as more effective. The present online experiment (conducted in April 2021) investigated people's perceptions of vaccines and remedies within the context of the current SARS-CoV-2 pandemic. A 2x2 between-subject design with type of remedy (natural vs. synthetic) and salience of SARS-CoV-2 pandemic (high vs. low) was conducted in Switzerland in spring 2021 (N = 452). The data did not provide evidence of a curative mindset for preventive remedies, as the participants exhibited a clear preference for the natural remedy compared to the synthetic remedy. Our study stresses the importance of understanding people's mindsets on how to protect themselves from infection with a virus during an ongoing pandemic to tackle misinformation and vaccine hesitancy.


Subject(s)
COVID-19/psychology , Patient Acceptance of Health Care/psychology , /psychology , Adult , Aged , COVID-19/prevention & control , COVID-19 Vaccines/pharmacology , Communication , Consumer Behavior , Dissent and Disputes , Female , Humans , Information Dissemination , Male , Middle Aged , Pandemics/prevention & control , Patient Acceptance of Health Care/statistics & numerical data , SARS-CoV-2/pathogenicity , Switzerland , Vaccination , Vaccines
10.
PLoS One ; 17(3): e0263671, 2022.
Article in English | MEDLINE | ID: covidwho-1742001

ABSTRACT

Novel therapeutic strategies are needed to control the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) pandemic. Here, we present a protocol to anchor the SARS-CoV-2 spike (S-)protein in the cytoplasmic membranes of erythrocyte liposomes. A surfactant was used to stabilize the S-protein's structure in the aqueous environment before insertion and to facilitate reconstitution of the S-proteins in the erythrocyte membranes. The insertion process was studied using coarse grained Molecular Dynamics (MD) simulations. Liposome formation and S-protein anchoring was studied by dynamic light scattering (DLS), ELV-protein co-sedimentation assays, fluorescent microcopy and cryo-TEM. The Erythro-VLPs (erythrocyte based virus like particles) have a well defined size of ∼200 nm and an average protein density on the outer membrane of up to ∼300 proteins/µm2. The correct insertion and functional conformation of the S-proteins was verified by dose-dependent binding to ACE-2 (angiotensin converting enzyme 2) in biolayer interferometry (BLI) assays. Seroconversion was observed in a pilot mouse trial after 14 days when administered intravenously, based on enzyme-linked immunosorbent assays (ELISA). This red blood cell based platform can open novel possibilities for therapeutics for the coronavirus disease (COVID-19) including variants, and other viruses in the future.


Subject(s)
COVID-19 Vaccines , COVID-19 , Erythrocyte Membrane , Molecular Dynamics Simulation , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus , Vaccines, Virus-Like Particle , Animals , COVID-19/immunology , COVID-19/prevention & control , COVID-19 Vaccines/chemistry , COVID-19 Vaccines/immunology , COVID-19 Vaccines/pharmacology , Erythrocyte Membrane/chemistry , Erythrocyte Membrane/immunology , Female , Liposomes , Mice , Pilot Projects , Protein Domains , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/pharmacology , Vaccines, Virus-Like Particle/chemistry , Vaccines, Virus-Like Particle/immunology , Vaccines, Virus-Like Particle/pharmacology
11.
Inflamm Bowel Dis ; 27(10): 1703-1705, 2021 Oct 18.
Article in English | MEDLINE | ID: covidwho-1740876

ABSTRACT

The recent emergency use authorization of a third COVID-19 vaccine means that most patients with inflammatory bowel disease (IBD) will soon be eligible to be vaccinated. Gastroenterology clinicians should be prepared to address patients' concerns regarding safety and efficacy of vaccines. They should also strongly recommend that all their patients be vaccinated with a COVID-19 vaccine. Additionally, they should be prepared to educate patients about logistics that will result in successful vaccination completion. All these measures will be crucial to ensure high uptake among their patients with IBD.


Subject(s)
COVID-19 Vaccines/pharmacology , COVID-19 , Gastroenterologists , Inflammatory Bowel Diseases , Vaccination , COVID-19/epidemiology , COVID-19/prevention & control , Humans , Inflammatory Bowel Diseases/epidemiology , Inflammatory Bowel Diseases/immunology , Inflammatory Bowel Diseases/psychology , Patient Participation/methods , Patient Participation/psychology , Physician's Role , Preventive Health Services , Risk Assessment , SARS-CoV-2 , Vaccination/methods , Vaccination/psychology , Vaccination Coverage/methods
12.
Korean J Intern Med ; 37(2): 455-459, 2022 03.
Article in English | MEDLINE | ID: covidwho-1737117

ABSTRACT

BACKGROUND/AIMS: Data comparing the antibody responses of different coronavirus disease 2019 (COVID-19) vaccine platforms according to dose with natural severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection-induced antibody responses are limited. METHODS: Blood samples from adult patients with mild and severe COVID-19 and healthcare workers who received ChAdOx1 nCoV-19 vaccine (2nd dose at 12-week intervals) and BNT162b2 vaccine (2nd dose at 3-week intervals) were collected and compared by immunoglobulin G immune responses to SARS-CoV-2 specific spike protein using an in-house-developed enzyme-linked immunosorbent assay. RESULTS: A total of 53 patients, including 12 and 41 with mild and severe COVID-19, respectively, were analyzed. In addition, a total of 73 healthcare workers, including 37 who received ChAdOx1 nCoV-19 and 36 who received BNT162b2, were enrolled. Antibody responses after the first and second doses of the ChAdOx1 nCoV-19 vaccine or the first dose of the BNT162b2 vaccine were similar to those in convalescent patients with mild COVID-19, but lower than those in convalescent patients with severe COVID-19, respectively. However, after the second dose of the BNT162b2 vaccine, the antibody response was comparable to that in convalescent patients with severe COVID-19. CONCLUSION: Our data suggest that the second dose of mRNA vaccination may be more beneficial in terms of long-term immunity and prevention of SARS-CoV-2 variant infection than a single dose of COVID-19 vaccination or homologous second challenge ChAdOx1 nCoV-19.


Subject(s)
Antibody Formation , COVID-19 , SARS-CoV-2 , Adult , Antibody Formation/drug effects , /pharmacology , COVID-19/immunology , COVID-19/prevention & control , COVID-19 Vaccines/immunology , COVID-19 Vaccines/pharmacology , COVID-19 Vaccines/therapeutic use , /pharmacology , Humans
13.
Chem Commun (Camb) ; 58(24): 3925-3928, 2022 Mar 22.
Article in English | MEDLINE | ID: covidwho-1730326

ABSTRACT

Adjuvants are important components in vaccines to increase the immunogenicity of proteins and induce optimal immunity. In this study, we designed a novel ternary adjuvant system Alum + c-GAMP + poly(I:C) with STING agonist 3,3'-c-GAMP (c-GAMP) and TLR3 agonist poly(I:C) co-adsorbed on the conventional adjuvant aluminum gel (Alum), and further constructed an S1 protein vaccine. Two doses of vaccination with the ternary adjuvant vaccine were sufficient to induce a balanced Th1/Th2 immune response and robust humoral and cellular immunity. Additionally, the ternary adjuvant group had effective neutralizing activity against live virus SARS-CoV-2 and pseudovirus of all variants of concern (alpha, beta, gamma, delta and omicron). These results indicate that the ternary adjuvants have a significant synergistic effect and can rapidly trigger potent immune responses; the combination of the ternary adjuvant system with S1 protein is a promising COVID-19 vaccine candidate.


Subject(s)
COVID-19 , SARS-CoV-2 , Adjuvants, Immunologic/pharmacology , Alum Compounds , Aluminum , Animals , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines/pharmacology , Humans , Immunity, Cellular , Mice , Mice, Inbred BALB C , Poly I
14.
Signal Transduct Target Ther ; 7(1): 69, 2022 03 03.
Article in English | MEDLINE | ID: covidwho-1721495

ABSTRACT

Emerging SARS-CoV-2 variants and the gradually decreasing neutralizing antibodies over time post vaccination have led to an increase in incidents of breakthrough infection across the world. To investigate the potential protective effect of the recombinant protein subunit COVID-19 vaccine targeting receptor-binding domain (RBD) (PS-RBD) and whole inactivated virus particle vaccine (IV) against the variant strains, in this study, rhesus macaques were immunized with PS-RBD or IV vaccine, followed by a Beta variant (B.1.351) challenge. Although neutralizing activity against the Beta variant was reduced compared with that against the prototype, the decreased viral load in both upper and lower respiratory tracts, milder pathological changes, and downregulated inflammatory cytokine levels in lung tissues after challenge demonstrated that PS-RBD and IV still provided effective protection against the Beta variant in the macaque model. Furthermore, PS-RBD-induced macaque sera possessed general binding and neutralizing activity to Alpha, Beta, Delta, and Omicron variants in our study, though the neutralizing antibody (NAb) titers declined by varying degrees, demonstrating potential protection of PS-RBD against current circulating variants of concern (VOCs). Interestingly, although the IV vaccine-induced extremely low neutralizing antibody titers against the Beta variant, it still showed reduction for viral load and significantly alleviated pathological change. Other correlates of vaccine-induced protection (CoP) like antibody-dependent cellular cytotoxicity (ADCC) and immune memory were both confirmed to be existing in IV vaccinated group and possibly be involved in the protective mechanism.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines , COVID-19 , Immunogenicity, Vaccine , SARS-CoV-2/immunology , Animals , COVID-19/immunology , COVID-19/prevention & control , COVID-19 Vaccines/immunology , COVID-19 Vaccines/pharmacology , Humans , Macaca mulatta , Vaccines, Inactivated/immunology , Vaccines, Inactivated/pharmacology , Vaccines, Synthetic/immunology , Vaccines, Synthetic/pharmacology
15.
J Am Soc Nephrol ; 32(9): 2147-2152, 2021 09.
Article in English | MEDLINE | ID: covidwho-1708655

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with a high rate of mortality in patients with ESKD, and vaccination is hoped to prevent infection. METHODS: Between January 18 and February 24, 2021, 225 kidney transplant recipients (KTRs) and 45 patients on hemodialysis (HDPs) received two injections of mRNA BNT162b2 vaccine. The postvaccinal humoral and cellular response was explored in the first 45 KTRs and ten HDPs. RESULTS: After the second dose, eight HDPs (88.9%) and eight KTRs (17.8%) developed antispike SARS-CoV-2 antibodies (P<0.001). Median titers of antibodies in responders were 1052 AU/ml (IQR, 515-2689) in HDPs and 671 AU/ml (IQR, 172-1523) in KTRs (P=0.40). Nine HDPs (100%) and 26 KTRs (57.8%) showed a specific T cell response (P=0.06) after the second injection. In responders, median numbers of spike-reactive T cells were 305 SFCs per 106 CD3+ T cells (IQR, 95-947) in HDPs and 212 SFCs per 106 CD3+ T cells (IQR, 61-330) in KTRs (P=0.40). In KTRs, the immune response to BNT162b2 seemed influenced by the immunosuppressive regimen, particularly tacrolimus or belatacept. CONCLUSION: Immunization with BNT162b2 seems more efficient in HDPs, indicating that vaccination should be highly recommended in these patients awaiting a transplant. However, the current vaccinal strategy for KTRs may not provide effective protection against COVID-19 and will likely need to be improved.


Subject(s)
Antibodies, Viral/biosynthesis , COVID-19 Vaccines/pharmacology , COVID-19/immunology , Kidney Transplantation , Renal Dialysis , SARS-CoV-2/immunology , T-Lymphocytes/immunology , Aged , COVID-19/complications , COVID-19/prevention & control , COVID-19 Vaccines/administration & dosage , Cohort Studies , Female , Humans , Immunocompromised Host , Immunosuppressive Agents/adverse effects , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/immunology , Kidney Failure, Chronic/therapy , Kidney Transplantation/adverse effects , Male , Middle Aged , Pandemics , RNA, Messenger/genetics , Retrospective Studies , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Transplant Recipients
16.
Int J Mol Sci ; 23(4)2022 Feb 16.
Article in English | MEDLINE | ID: covidwho-1708485

ABSTRACT

Despite the fact that a range of vaccines against COVID-19 have already been created and are used for mass vaccination, the development of effective, safe, technological, and affordable vaccines continues. We have designed a vaccine that combines the recombinant protein and DNA vaccine approaches in a self-assembled particle. The receptor-binding domain (RBD) of the spike protein of SARS-CoV-2 was conjugated to polyglucin:spermidine and mixed with DNA vaccine (pVAXrbd), which led to the formation of particles of combined coronavirus vaccine (CCV-RBD) that contain the DNA vaccine inside and RBD protein on the surface. CCV-RBD particles were characterized with gel filtration, electron microscopy, and biolayer interferometry. To investigate the immunogenicity of the combined vaccine and its components, mice were immunized with the DNA vaccine pVAXrbd or RBD protein as well as CCV-RBD particles. The highest antigen-specific IgG and neutralizing activity were induced by CCV-RBD, and the level of antibodies induced by DNA or RBD alone was significantly lower. The cellular immune response was detected only in the case of DNA or CCV-RBD vaccination. These results demonstrate that a combination of DNA vaccine and RBD protein in one construct synergistically increases the humoral response to RBD protein in mice.


Subject(s)
COVID-19 Vaccines/chemistry , COVID-19 Vaccines/pharmacology , Immunity, Humoral/drug effects , Spike Glycoprotein, Coronavirus/chemistry , Animals , Binding Sites , COVID-19 Vaccines/immunology , Chlorocebus aethiops , Dextrans/chemistry , Female , HEK293 Cells , Humans , Mice, Inbred BALB C , Protein Domains , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Spermidine/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Vaccines, DNA/genetics , Vaccines, DNA/immunology , Vaccines, DNA/pharmacology , Vero Cells
17.
Nat Hum Behav ; 6(2): 193-206, 2022 02.
Article in English | MEDLINE | ID: covidwho-1704182

ABSTRACT

The greatest hope for a return to normalcy following the COVID-19 pandemic is worldwide vaccination. Yet, a relaxation of social distancing that allows increased transmissibility, coupled with selection pressure due to vaccination, will probably lead to the emergence of vaccine resistance. We analyse the evolutionary dynamics of COVID-19 in the presence of dynamic contact reduction and in response to vaccination. We use infection and vaccination data from six different countries. We show that under slow vaccination, resistance is very likely to appear even if social distancing is maintained. Under fast vaccination, the emergence of mutants can be prevented if social distancing is maintained during vaccination. We analyse multiple human factors that affect the evolutionary potential of the virus, including the extent of dynamic social distancing, vaccination campaigns, vaccine design, boosters and vaccine hesitancy. We provide guidelines for policies that aim to minimize the probability of emergence of vaccine-resistant variants.


Subject(s)
COVID-19 Vaccines , Drug Resistance, Viral , Immunogenicity, Vaccine , Mass Vaccination , Physical Distancing , SARS-CoV-2 , COVID-19 , COVID-19 Vaccines/immunology , COVID-19 Vaccines/pharmacology , Communicable Disease Control/organization & administration , Drug Resistance, Viral/drug effects , Drug Resistance, Viral/immunology , Humans , Mass Vaccination/methods , Mass Vaccination/statistics & numerical data , Policy Making , Probability , SARS-CoV-2/drug effects , SARS-CoV-2/physiology , Stochastic Processes
18.
PLoS Med ; 19(2): e1003916, 2022 02.
Article in English | MEDLINE | ID: covidwho-1703635

ABSTRACT

BACKGROUND: In 2020, the SARS-CoV-2 (COVID-19) pandemic and lockdown control measures threatened to disrupt routine childhood immunisation programmes with early reports suggesting uptake would fall. In response, public health bodies in Scotland and England collected national data for childhood immunisations on a weekly or monthly basis to allow for rapid analysis of trends. The aim of this study was to use these data to assess the impact of different phases of the pandemic on infant and preschool immunisation uptake rates. METHODS AND FINDINGS: We conducted an observational study using routinely collected data for the year prior to the pandemic (2019) and immediately before (22 January to March 2020), during (23 March to 26 July), and after (27 July to 4 October) the first UK "lockdown". Data were obtained for Scotland from the Public Health Scotland "COVID19 wider impacts on the health care system" dashboard and for England from ImmForm. Five vaccinations delivered at different ages were evaluated; 3 doses of "6-in-1" diphtheria, tetanus, pertussis, polio, Haemophilus influenzae type b, and hepatitis B vaccine (DTaP/IPV/Hib/HepB) and 2 doses of measles, mumps, and rubella (MMR) vaccine. This represented 439,754 invitations to be vaccinated in Scotland and 4.1 million for England. Uptake during the 2020 periods was compared to the previous year (2019) using binary logistic regression analysis. For Scotland, uptake within 4 weeks of a child becoming eligible by age was analysed along with geographical region and indices of deprivation. For Scotland and England, we assessed whether immunisations were up-to-date at approximately 6 months (all doses 6-in-1) and 16 to 18 months (first MMR) of age. We found that uptake within 4 weeks of eligibility in Scotland for all the 5 vaccines was higher during lockdown than in 2019. Differences ranged from 1.3% for first dose 6-in-1 vaccine (95.3 versus 94%, odds ratio [OR] compared to 2019 1.28, 95% confidence intervals [CIs] 1.18 to 1.39) to 14.3% for second MMR dose (66.1 versus 51.8%, OR compared to 2019 1.8, 95% CI 1.74 to 1.87). Significant increases in uptake were seen across all deprivation levels. In England, fewer children due to receive their immunisations during the lockdown period were up to date at 6 months (6-in-1) or 18 months (first dose MMR). The fall in percentage uptake ranged from 0.5% for first 6-in-1 (95.8 versus 96.3%, OR compared to 2019 0.89, 95% CI 0.86- to 0.91) to 2.1% for third 6-in-1 (86.6 versus 88.7%, OR compared to 2019 0.82, 95% CI 0.81 to 0.83). The use of routinely collected data used in this study was a limiting factor as detailed information on potential confounding factors were not available and we were unable to eliminate the possibility of seasonal trends in immunisation uptake. CONCLUSIONS: In this study, we observed that the national lockdown in Scotland was associated with an increase in timely childhood immunisation uptake; however, in England, uptake fell slightly. Reasons for the improved uptake in Scotland may include active measures taken to promote immunisation at local and national levels during this period and should be explored further. Promoting immunisation uptake and addressing potential vaccine hesitancy is particularly important given the ongoing pandemic and COVID-19 vaccination campaigns.


Subject(s)
COVID-19 Vaccines/pharmacology , COVID-19/epidemiology , COVID-19/prevention & control , Routinely Collected Health Data , SARS-CoV-2/drug effects , Child , Child, Preschool , Communicable Disease Control/methods , Female , Humans , Immunization Programs/statistics & numerical data , Infant , Male , SARS-CoV-2/pathogenicity , Vaccination/statistics & numerical data
19.
Clin Appl Thromb Hemost ; 28: 10760296211056648, 2022.
Article in English | MEDLINE | ID: covidwho-1685920

ABSTRACT

The progress in the development of various vaccine platforms against SARS-CoV-2 have been rather remarkable owing to advancement in molecular and biologic sciences. Most of the current vaccines and those in development focus on targeting the viral spike proteins by generating antibodies of varying spectrum. These vaccines represent a variety of platforms including whole virus vaccines, viral vector vaccines, nucleic acid vaccines representing RNA, DNA, and their hybrid forms.The therapeutic efficacy of these vaccines varies owing to their pharmacodynamic individualities. COVID-19 variants are capable of inducing different pathologic responses and some of which may be resistant to antibodies generated by current vaccines. The current clinical use of these vaccines has been through emergency use authorization until recently. Moreover, the efficacy and safety of these vaccines have been tested in substantial numbers of individuals but studies in special populations that better reflect the global population are pending results. These specialized populations include young children, immunocompromised patients, pregnant individuals, and other specialized groups. Combination approaches, molecularly modified vaccination approaches, and vaccines conferring longer periods of immunity are being currently being investigated, as well as pharmacovigilance studies.The continual transformation of SARS-CoV-2 and its variants are of concern along with the breakthrough infections. These considerations pose new challenges for the development of vaccination platforms. For this purpose, booster doses, combination vaccine approaches, and other modalities are being discussed. This review provides an updated account of currently available vaccines and those in advanced development with reference to their composition and mechanisms of action.A discussion on the use of vaccines in special populations including immunocompromised patients, pregnant women and other specialized populations are also included.


Subject(s)
COVID-19 Vaccines/pharmacology , COVID-19/prevention & control , SARS-CoV-2/immunology , /methods , Adolescent , COVID-19/immunology , COVID-19/virology , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/therapeutic use , Child , Female , Humans , Immunocompromised Host , Pregnancy , Pregnancy Complications, Infectious/immunology , Pregnancy Complications, Infectious/prevention & control , Pregnancy Complications, Infectious/virology
20.
JCI Insight ; 7(5)2022 03 08.
Article in English | MEDLINE | ID: covidwho-1662370

ABSTRACT

Benchmarks for protective immunity from infection or severe disease after SARS-CoV-2 vaccination are still being defined. Here, we characterized virus neutralizing and ELISA antibody levels, cellular immune responses, and viral variants in 4 separate groups: healthy controls (HCs) weeks (early) or months (late) following vaccination in comparison with symptomatic patients with SARS-CoV-2 after partial or full mRNA vaccination. During the period of the study, most symptomatic breakthrough infections were caused by the SARS-CoV-2 Alpha variant. Neutralizing antibody levels in the HCs were sustained over time against the vaccine parent virus but decreased against the Alpha variant, whereas IgG titers and T cell responses against the parent virus and Alpha variant declined over time. Both partially and fully vaccinated patients with symptomatic infections had lower virus neutralizing antibody levels against the parent virus than the HCs, similar IgG antibody titers, and similar virus-specific T cell responses measured by IFN-γ. Compared with HCs, neutralization activity against the Alpha variant was lower in the partially vaccinated infected patients and tended to be lower in the fully vaccinated infected patients. In this cohort of breakthrough infections, parent virus neutralization was the superior predictor of breakthrough infections with the Alpha variant of SARS-CoV-2.


Subject(s)
Adaptive Immunity , Antibodies, Viral/immunology , COVID-19 Vaccines/pharmacology , COVID-19/virology , SARS-CoV-2/immunology , Vaccination/methods , Vaccines, Synthetic/pharmacology , /pharmacology , Adult , Aged , COVID-19/epidemiology , COVID-19/prevention & control , Female , Follow-Up Studies , Humans , Male , Middle Aged , Pandemics , Population Surveillance , Retrospective Studies , United States/epidemiology , Young Adult
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