scholarly journals SARS-CoV-2 Vaccines Elicit Durable Immune Responses in Infant Rhesus Macaques

2021 ◽  
Author(s):  
Carolina Garrido ◽  
Alan D. Curtis ◽  
Maria Dennis ◽  
Sachi H. Pathak ◽  
Hongmei Gao ◽  
...  
Keyword(s):  
Immune Responses ◽  
Protective Immunity ◽  
Rhesus Macaques ◽  
Herd Immunity ◽  
Cellular Responses ◽  
Infectious Dose ◽  
Vaccine Candidates ◽  
Cell Responses ◽  
High Magnitude ◽  
Infant Rhesus

AbstractEarly life SARS-CoV-2 vaccination has the potential to provide lifelong protection and achieve herd immunity. To evaluate SARS-CoV-2 infant vaccination, we immunized two groups of 8 infant rhesus macaques (RMs) at weeks 0 and 4 with stabilized prefusion SARS-CoV-2 S-2P spike (S) protein, either encoded by mRNA encapsulated in lipid nanoparticles (mRNA-LNP) or mixed with 3M-052-SE, a TLR7/8 agonist in a squalene emulsion (Protein+3M-052-SE). Neither vaccine induced adverse effects. High magnitude S-binding IgG and neutralizing infectious dose 50 (ID50) >103 were elicited by both vaccines. S-specific T cell responses were dominated by IL-17, IFN-γ, or TNF-α. Antibody and cellular responses were stable through week 22. The S-2P mRNA-LNP and Protein-3M-052-SE vaccines are promising pediatric SARS-CoV-2 vaccine candidates to achieve durable protective immunity.One-Sentence SummarySARS-CoV-2 vaccines are well-tolerated and highly immunogenic in infant rhesus macaques

scholarly journals Assessment of immunogenicity and protective efficacy of ZyCoV-D DNA vaccine candidates in Rhesus macaques against SARS-CoV-2 infection

2021 ◽  
Author(s):  
Pragya D Yadav ◽  
Sanjay Kumar ◽  
Kshitij Agarwal ◽  
Mukul Jain ◽  
Dilip R Patil ◽  
...  
Keyword(s):  
Vaccine Candidate ◽  
Protective Efficacy ◽  
Rhesus Macaques ◽  
Herd Immunity ◽  
Lavage Fluid ◽  
Injection System ◽  
Protective Measure ◽  
Vaccine Candidates ◽  
Virus Challenge ◽  
Syringe Needle

AbstractVaccines remain the key protective measure to achieve herd immunity to control the disease burden and stop COVID-19 pandemic. We have developed and assessed the immunogenicity and protective efficacy of two formulations (1mg and 2mg) of ZyCoV-D (a plasmid DNA based vaccine candidates) administered through Needle Free Injection System (NFIS) and syringe-needle (intradermal) in rhesus macaques with three dose vaccine regimens. The vaccine candidate 2mg dose administered using Needle Free Injection System (NFIS) elicited a significant immune response with development of SARS-CoV-2 S1 spike region specific IgG and neutralizing antibody (NAb) titers during the immunization phase and significant enhancement in the levels after the virus challenge. In 2 mg NFIS group the IgG and NAb titers were maintained and showed gradual rise during the immunization period (15 weeks) and till 2 weeks after the virus challenge. It also conferred better protection to macaques evident by the viral clearance from nasal swab, throat swab and bronchoalveolar lavage fluid specimens in comparison with macaques from other immunized groups. In contrast, the animals from placebo group developed high levels of viremia and lung disease following the virus challenge. Besides this, the vaccine candidate also induced increase lymphocyte proliferation and cytokines response (IL-6, IL-5).The administration of the vaccine candidate with NFIS generated a better immunogenicity response in comparison to syringe-needle (intradermal route). The study demonstrated immunogenicity and protective efficacy of the vaccine candidate, ZyCoV-D in rhesus macaques.

scholarly journals Inhibition of protective immunity against Staphylococcus aureus infection by MHC-restricted immunodominance is overcome by vaccination

2020 ◽  
Vol 6 (14) ◽  
pp. eaaw7713 ◽  
Author(s):  
Youhui Si ◽  
Fan Zhao ◽  
Pavani Beesetty ◽  
Daniela Weiskopf ◽  
Zhaotao Li ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
T Cell ◽  
Immune Responses ◽  
Protective Immunity ◽  
T Cell Responses ◽  
Individual Variability ◽  
Host Genetics ◽  
Cell Responses ◽  
Histocompatibility Complex ◽  
Mhc Tetramers

Recurrent Staphylococcus aureus infections are common, despite robust immune responses. S. aureus infection elicited protective antibody and T cell responses in mice that expressed the Major Histocompatibility Complex (MHC) of the H-2d haplotype, but not H-2b, demonstrating that host genetics drives individual variability. Vaccination with a-toxin or leukotoxin E (LukE) elicited similar antibody and T cell responses in mice expressing H-2d or H-2b, but vaccine-elicited responses were inhibited by concomitant infection in H-2d–expressing mice. These findings suggested that competitive binding of microbial peptides to host MHC proteins determines the specificity of the immunodominant response, which was confirmed using LukE-derived peptide-MHC tetramers. A vaccine that elicited T cell and antibody responses protected mice that expressed H-2d or H-2b, demonstrating that vaccination can overcome MHC-restricted immunodominance. Together, these results define how host genetics determine whether immunity elicted by S. aureus is protective and provide a mechanistic roadmap for future vaccine design.

scholarly journals A specific role for TLR1 in protective TH17 immunity during mucosal infection

2012 ◽  
Vol 209 (8) ◽  
pp. 1437-1444 ◽  
Author(s):  
R. William DePaolo ◽  
Karishma Kamdar ◽  
Samira Khakpour ◽  
Yui Sugiura ◽  
Wenxia Wang ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
Protective Immunity ◽  
Systemic Infection ◽  
T Cell Responses ◽  
Oral Infection ◽  
Immune Functions ◽  
Oral Infections ◽  
Cell Responses ◽  
Th1 Immune Responses

The balance between regulatory and inflammatory immune responses is critical to maintain intestinal homeostasis. Furthermore, the nature of the inflammatory response needs to be tailored to the tissue to provide proper protective immunity while preserving host integrity. TLR2 (Toll-like receptor 2) is a unique TLR in that it has been shown to promote regulatory and inflammatory T cell responses. Using Yersinia enterocolitica, we show that oral infection promotes TH17 immunity, whereas systemic infection promotes TH1 immunity. Furthermore, induction of TH17 immunity during oral infection is dependent on TLR1 and results from the combinatorial effect of TLR2/TLR1-induced IL-6 and IL-23 and the presence of TGF-β in the intestinal environment. Interestingly, TLR2/TLR1 was not involved in TH1 immune responses during systemic infection, whereas the TLR2/TLR6 receptor complex induced IL-10+ regulatory T cell responses during both systemic and oral infections. Our results reveal that the route of infection is central in determining which pathways provide protective immunity. Furthermore, they also demonstrate that TLR2 has dual immune functions in the gut and identify TLR1 as a critical innate receptor for protective intestinal TH17 immunity.

scholarly journals T-Cell Immune Response Assessment as a Complement to Serology and Intranasal Protection Assays in Determining the Protective Immunity Induced by Acellular Pertussis Vaccines in Mice

2003 ◽  
Vol 10 (4) ◽  
pp. 637-642 ◽  
Author(s):  
C. M. Ausiello ◽  
R. Lande ◽  
P. Stefanelli ◽  
C. Fazio ◽  
G. Fedele ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cell ◽  
Immune Responses ◽  
Pertussis Toxin ◽  
Protective Immunity ◽  
T Cell Responses ◽  
Additional Tool ◽  
Cell Responses ◽  
T Cell Immune Responses ◽  
Ifn Γ

ABSTRACT The relative value of antibodies and/or T-cell immune responses to Bordetella pertussis antigens in the immunity induced by acellular pertussis (aP) vaccines is still an open issue, probably due to the incomplete knowledge on the mechanisms of protective immunity to pertussis. The relevance of T-cell immune responses in protection from pertussis has been demonstrated in murine and human models of infection; thus, in this study, the ability of different vaccine preparations of three component (pertussis toxin, filamentous hemagglutinin, and pertactin) aP vaccines to induce T-cell responses was investigated in mice. All vaccine preparations examined passed the immunogenicity control test, based on antibody titer assessment, according to European Pharmacopoeia standards, and protected mice from B. pertussis intranasal challenge, but not all preparations were able to prime T cells to pertussis toxin, the specific B. pertussis antigen. In particular, one vaccine preparation was unable to induce proliferation and gamma interferon (IFN-γ) production while the other two gave borderline results. The evaluation of T-cell responses to pertussis toxin antigen may provide information on the protective immunity induced by aP vaccines in animal models. Considering the critical role of the axis interleukin-12-IFN-γ for protection from pertussis, our results suggest that testing the induction of a key protective cytokine such as IFN-γ could be an additional tool for the evaluation of the immune response induced by aP vaccines.

scholarly journals Differential CD4+ versus CD8+ T-Cell Responses Elicited by Different Poxvirus-Based Human Immunodeficiency Virus Type 1 Vaccine Candidates Provide Comparable Efficacies in Primates

2008 ◽  
Vol 82 (6) ◽  
pp. 2975-2988 ◽  
Author(s):  
Petra Mooij ◽  
Sunita S. Balla-Jhagjhoorsingh ◽  
Gerrit Koopman ◽  
Niels Beenhakker ◽  
Patricia van Haaften ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cell ◽  
Immune Responses ◽  
Vaccinia Virus ◽  
T Cell Responses ◽  
Vaccine Candidates ◽  
Cell Responses ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Poxvirus vectors have proven to be highly effective for boosting immune responses in diverse vaccine settings. Recent reports reveal marked differences in the gene expression of human dendritic cells infected with two leading poxvirus-based human immunodeficiency virus (HIV) vaccine candidates, New York vaccinia virus (NYVAC) and modified vaccinia virus Ankara (MVA). To understand how complex genomic changes in these two vaccine vectors translate into antigen-specific systemic immune responses, we undertook a head-to-head vaccine immunogenicity and efficacy study in the pathogenic HIV type 1 (HIV-1) model of AIDS in Indian rhesus macaques. Differences in the immune responses in outbred animals were not distinguished by enzyme-linked immunospot assays, but differences were distinguished by multiparameter fluorescence-activated cell sorter analysis, revealing a difference between the number of animals with both CD4+ and CD8+ T-cell responses to vaccine inserts (MVA) and those that elicit a dominant CD4+ T-cell response (NYVAC). Remarkably, vector-induced differences in CD4+/CD8+ T-cell immune responses persisted for more than a year after challenge and even accompanied antigenic modulation throughout the control of chronic infection. Importantly, strong preexposure HIV-1/simian immunodeficiency virus-specific CD4+ T-cell responses did not prove deleterious with respect to accelerated disease progression. In contrast, in this setting, animals with strong vaccine-induced polyfunctional CD4+ T-cell responses showed efficacies similar to those with stronger CD8+ T-cell responses.

scholarly journals Intranasal Vaccination with the Recombinant Listeria monocytogenes ΔactA prfA*Mutant Elicits Robust Systemic and Pulmonary Cellular Responses and Secretory Mucosal IgA

2011 ◽  
Vol 18 (4) ◽  
pp. 640-646 ◽  
Author(s):  
Jin Qiu ◽  
Lin Yan ◽  
Jianbo Chen ◽  
Crystal Y. Chen ◽  
Ling Shen ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Immune Responses ◽  
Cellular Response ◽  
Cellular Responses ◽  
Broth Culture ◽  
Intravenous Route ◽  
Content Type ◽  
Vaccine Candidates ◽  
Ifn Γ ◽  
Subcutaneous Immunization

ABSTRACTWe previously showed that recombinant (r)Listeria monocytogenescarrying ΔactAand a selectedprfA*mutation (r-ListeriaΔactA prfA*) secreted >100-fold more immunogen in broth culture than wild-type r-Listeriaor r-ListeriaΔactAand elicited much greater cellular and humoral immune responses than r-ListeriaΔactAafter intravenous vaccination of mice. Here, we conducted comparative studies evaluating vaccine-elicited immune responses in systemic and mucosal sites after intranasal, intravenous, intraperitoneal, or subcutaneous immunization of mice with r-ListeriaΔactA prfA*vaccine candidates. Intranasal vaccination of mice with r-ListeriaΔactA prfA* vaccine candidates elicited a robust gamma interferon-positive (IFN-γ+) cellular response in systemic sites, although intravenous or intraperitoneal immunization was more efficient. Surprisingly, intranasal vaccination elicited an appreciable pulmonary IFN-γ+cellular response that was nonstatistically higher than the magnitude induced by the intravenous route but was significantly greater than that elicited by subcutaneous immunization. Furthermore, although intranasal r-ListeriaΔactA prfA*delivery induced poor systemic IgG responses, intranasal vaccination elicited appreciable secretory immunogen-specific IgA titers that were similar to or higher in mucosal fluid than those induced by subcutaneous and intravenous immunizations. Thus, intranasal vaccination with r-ListeriaΔactA prfA*appears to be a useful approach for eliciting robust systemic and pulmonary cellular responses and measurable secretory mucosal IgA titers.

scholarly journals Differential Immunogenicity of BNT162b2 or ChAdOx1 Vaccines After Extended-Interval Homologous Dual Vaccination in Older People

2021 ◽  
Author(s):  
Helen Parry ◽  
Rachel Bruton ◽  
Christine Stephens ◽  
Kevin Brown ◽  
Gayatri Amirthalingam ◽  
...  
Keyword(s):  
Immune Responses ◽  
Older People ◽  
Natural Infection ◽  
Cellular Responses ◽  
Antibody Responses ◽  
Vaccine Responses ◽  
Cell Responses ◽  
Boost Vaccine ◽  
The Uk ◽  
Cellular Immune

Abstract BackgroundSeveral SARS-CoV-2 vaccines have shown clinical efficacy against Covid-19 infection but there remains uncertainty about the immune responses elicited by different regimens. This is a particularly important question for older people who are at increased clinical risk following infection and in whom immune senescence may limit vaccine responses. The BNT162b2 mRNA and ChAdOx1 adenovirus vaccines were the first two vaccines deployed in the UK programme using an 8-12 week ‘extended interval’.ObjectivesWe undertook analysis of the spike-specific antibody and cellular immune response in 131 participants aged 80+ years after the second dose of ‘extended interval’ dual vaccination with either BNT162b2 mRNA (n=54) or ChAdOx1 (n=77) adenovirus vaccine. Blood samples were taken 2-3 weeks after second vaccine and were paired with samples taken at 5-weeks after first vaccine which have been reported previously. Antibody responses were measured using the Elecsys® electrochemiluminescence immunoassay assay and cellular responses were assessed by IFN-g ELISpot. ResultsAntibody responses against spike protein became detectable in all donors following dual vaccination with either vaccine. 4 donors had evidence of previous natural infection which is known to boost vaccine responses. Within the 53 infection-naïve donors the median antibody titre was 4030 U/ml (IQR 1892-8530) following BNT162b2 dual vaccination and 1405 (IQR 469.5- 2543) in the 74 patients after the ChAdOx1 vaccine (p=<0.0001). Spike-specific T cell responses were observed in 30% and 49% of mRNA and ChAdOx1 recipients respectively and median responses were 1.4-times higher in ChAdOx1 vaccinees at 14 vs 20 spots/million respectively (p=0.022).ConclusionDual vaccination with BNT162b2 or ChAdOx1 induces strong humoral immunity in older people following an extended interval protocol. Antibody responses are 2.9-times higher following the mRNA regimen whilst cellular responses are 1.7-times higher with the adenovirus-based vaccine. Differential patterns of immunogenicity are therefore elicited from the two vaccine platforms. It will be of interest to assess the relative stability of immune responses after these homologous vaccine regimens in order to assess the potential need for vaccine boosting. Furthermore, these findings indicate that heterologous vaccine platforms may offer the opportunity to further optimize vaccine responses.

scholarly journals Robust immune responses after one dose of BNT162b2 mRNA vaccine dose in SARS-CoV-2 experienced individuals

2021 ◽  
Author(s):  
Marie I. Samanovic ◽  
Amber R. Cornelius ◽  
Sophie L. Gray-Gaillard ◽  
Joseph Richard Allen ◽  
Trishala Karmacharya ◽  
...  
Keyword(s):  
Immune Responses ◽  
Protective Efficacy ◽  
Vaccine Dose ◽  
Prior History ◽  
Vaccine Candidates ◽  
Antibody Secreting Cell ◽  
Cell Responses ◽  
Efficacy Trials ◽  
History Of ◽  
Humoral Responses

ABSTRACTThe use of COVID-19 vaccines will play a major role in helping to end the pandemic that has killed millions worldwide. COVID-19 vaccine candidates have resulted in robust humoral responses and protective efficacy in human trials, but efficacy trials excluded individuals with prior diagnosis of COVID-19. As a result, little is known about how immune responses induced by mRNA vaccine candidates differ in individuals who recovered from COVID-19. Here, we evaluated longitudinal immune responses to two-dose BNT162b2 mRNA vaccination in 13 adults who recovered from COVID-19, compared to 19 adults who did not have prior COVID-19 diagnosis. Consistent with prior studies of mRNA vaccines, we observed robust cytotoxic CD8 T cell responses in both cohorts. Furthermore, SARS-CoV-2-naive individuals had progressive increases in humoral and antigen-specific antibody-secreting cell (ASC) responses following each dose of vaccine, whereas SARS-CoV-2-experienced individuals demonstrated strong humoral and antigen-specific ASC responses to the first dose but muted responses to the second dose of the vaccine for the time points studied. Together, these data highlight the relevance of immunological history for understanding vaccine immune responses and may have significant implications for personalizing mRNA vaccination regimens used to prevent COVID-19.One Sentence SummaryPrior history of COVID-19 affects adaptive immune responses to mRNA vaccination.

scholarly journals SARS-CoV-2 infection induces germinal center responses with robust stimulation of CD4 T follicular helper cells in rhesus macaques

2020 ◽  
Author(s):  
Sonny R. Elizaldi ◽  
Yashavanth Shaan Lakshmanappa ◽  
Jamin W. Roh ◽  
Brian A. Schmidt ◽  
Timothy D. Carroll ◽  
...  
Keyword(s):  
Germinal Center ◽  
Protective Immunity ◽  
Viral Infections ◽  
Rhesus Macaques ◽  
Igg Antibodies ◽  
Cell Responses ◽  
Follicular Helper ◽  
Early Appearance ◽  
Iga Antibodies ◽  
Stimulation Of

ABSTRACTCD4 T follicular helper (Tfh) cells are important for the generation of long-lasting and specific humoral protection against viral infections. The degree to which SARS-CoV-2 infection generates Tfh cells and stimulates the germinal center response is an important question as we investigate vaccine options for the current pandemic. Here we report that, following infection with SARS-CoV-2, adult rhesus macaques exhibited transient accumulation of activated, proliferating Tfh cells in their peripheral blood on a transitory basis. The CD4 helper cell responses were skewed predominantly toward a Th1 response in blood, lung, and lymph nodes, reflective of the interferon-rich cytokine environment following infection. We also observed the generation of germinal center Tfh cells specific for the SARS-CoV-2 spike (S) and nucleocapsid (N) proteins, and a corresponding early appearance of antiviral serum IgG antibodies but delayed or absent IgA antibodies. Our data suggest that a vaccine promoting Th1-type Tfh responses that target the S protein may lead to protective immunity.

Vaccination of human subjects expands both specific and bystander memory T cells but antibody production remains vaccine specific

Blood ◽  
2006 ◽  
Vol 107 (7) ◽  
pp. 2806-2813 ◽  
Author(s):  
Gianfranco Di Genova ◽  
Joanna Roddick ◽  
Feargal McNicholl ◽  
Freda K. Stevenson
Keyword(s):  
Antibody Production ◽  
Protective Immunity ◽  
Cytokine Production ◽  
Human Subjects ◽  
Cellular Responses ◽  
T Helper ◽  
Purified Protein Derivative ◽  
Cell Responses ◽  
Common Antigens

AbstractHuman subjects maintain long-term immunologic memory against infective organisms but the mechanism is unclear. CD4+ T-helper memory (Thmem) cells are pivotal in controlling humoral and cellular responses, therefore their longevity and response to vaccination are critical for maintenance of protective immunity. To probe the dynamics of the Thmem-cell response to antigenic challenge, we investigated subjects following a booster injection with tetanus toxoid (TT). Expansion of TT-specific Thmem cells and cytokine production showed complex kinetics. Strikingly, parallel expansion and cytokine production occurred in pre-existing Thmem cells specific for 2 other common antigens: purified protein derivative of tuberculin and Candida albicans. Bystander expansion occurred in Thmem but not in Thnaive cells. Antibody production against TT peaked approximately 2 weeks after vaccination and gradually declined. However, pre-existing antibody against the other antigens did not change. It appears that although all Thmem cells are readily stimulated to expand, antibody responses are controlled by antigen availability. These findings relate to the maintenance of memory and have consequences for assessments of specific T-cell responses to vaccination.

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