scholarly journals Immunogenicity and Neutralizing Activity Comparison of SARS-CoV-2 Spike Full-Length and Subunit Domain Proteins in Young Adult and Old-Aged Mice

Vaccines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 316
Author(s):  
Ki-Hye Kim ◽  
Noopur Bhatnagar ◽  
Subbiah Jeeva ◽  
Judy Oh ◽  
Bo Ryoung Park ◽  
...  
Keyword(s):  
Young Adult ◽  
Receptor Binding ◽  
Vaccine Dose ◽  
The Elderly ◽  
Full Length ◽  
High Dose ◽  
Igg Antibodies ◽  
Neutralizing Activity ◽  
Aged Mice ◽  
Adjuvant Effects

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to be expanding the pandemic disease across the globe. Although SARS-CoV-2 vaccines were rapidly developed and approved for emergency use of vaccination in humans, supply and production difficulties are slowing down the global vaccination program. The efficacy of many different versions of vaccine candidates and adjuvant effects remain unknown, particularly in the elderly. In this study, we compared the immunogenic properties of SARS-CoV-2 full-length spike (S) ectodomain in young adult and aged mice, S1 with receptor binding domain, and S2 with fusion domain. Full-length S was more immunogenic and effective in inducing IgG antibodies after low dose vaccination, compared to the S1 subunit. Old-aged mice induced SARS-CoV-2 spike-specific IgG antibodies with neutralizing activity after high dose S vaccination. With an increased vaccine dose, S1 was highly effective in inducing neutralizing and receptor-binding inhibiting antibodies, although both S1 and S2 subunit domain vaccines were similarly immunogenic. Adjuvant effects were significant for effective induction of IgG1 and IgG2a isotypes, neutralizing and receptor-binding inhibiting antibodies, and antibody-secreting B cell and interferon-γ secreting T cell immune responses. Results of this study provide information in designing SARS-CoV-2 spike vaccine antigens and effective vaccination in the elderly.

scholarly journals Enhancing the Protective Immune Response against Botulism

2013 ◽  
Vol 81 (7) ◽  
pp. 2638-2644 ◽  
Author(s):  
Amanda Przedpelski ◽  
William H. Tepp ◽  
Abby R. Kroken ◽  
Zhuji Fu ◽  
Jung-Ja P. Kim ◽  
...  
Keyword(s):  
Immune Response ◽  
Receptor Binding ◽  
Low Dose ◽  
Binding Capacity ◽  
Vaccine Dose ◽  
Binding Pocket ◽  
Protective Immune Response ◽  
High Dose ◽  
Control And Prevention ◽  
Dose Vaccine

ABSTRACTThe need for a vaccine against botulism has increased since the discontinuation of the pentavalent (ABCDE) botulinum toxoid vaccine by the Centers for Disease Control and Prevention. The botulinum toxins (BoNTs) are the primary virulence factors and vaccine components against botulism. BoNTs comprise three domains which are involved in catalysis (LC), translocation (HCT), and host receptor binding (HCR). Recombinant HCR subunits have been used to develop the next generation of BoNT vaccines. Using structural studies and the known entry properties of BoNT/A, an HCR subunit vaccine against BoNT/A that contained the point mutation W1266A within the ganglioside binding pocket was designed. HCR/A(W1266A) did not enter primary neurons, and the crystal structure of HCR/A(W1266A) was virtually identical to that of wild-type HCR/A. Using a mouse model, experiments were performed using a high-dose vaccine and a low-dose vaccine. At a high vaccine dose, HCR/A and HCR/A(W1266A) elicited a protective immune response to BoNT/A challenge. At the low-dose vaccination, HCR/A(W1266A) was a more protective vaccine than HCR/A. α-HCR IgG titers correlated with protection from BoNT challenge, although titers to block HCR/A entry were greater in serum in HCR/A-vaccinated mice than in HCR/A(W1266A)-vaccinated mice. This study shows that removal of receptor binding capacity enhances potency of the subunit HCR vaccine. Vaccines that lack receptor binding capacity have the added property of limited off-target toxicity.

scholarly journals Safety of High-Dose Dabigatran in Elderly and Younger Patients with a Low Bleeding Risk: A Prospective Observational Study

Cardiology ◽  
2021 ◽  
pp. 1-5
Author(s):  
Aharon Erez ◽  
Gregory Golovchiner ◽  
Robert Klempfner ◽  
Ehud Kadmon ◽  
Gustavo Ruben Goldenberg ◽  
...  
Keyword(s):  
Observational Study ◽  
Elderly Patients ◽  
Prospective Observational Study ◽  
Bleeding Risk ◽  
The Elderly ◽  
High Dose ◽  
World Population ◽  
Younger Patients ◽  
End Point

<b><i>Introduction:</i></b> In patients with atrial fibrillation (AF) at risk for stroke, dabigatran 150 mg twice a day (DE150) is superior to warfarin for stroke prevention. However, there is paucity of data with respect to bleeding risk at this dose in elderly patients (≥75 years). We aimed to evaluate the safety of DE150 in comparison to warfarin in a real-world population with AF and low bleeding risk (HAS-BLED score ≤2). <b><i>Methods:</i></b> In this prospective observational study, 754 consecutive patients with AF and HAS-BLED score ≤2 were included. We compared outcome of elderly patients (age ≥75 tears) to younger patients (age &#x3c;75 years). The primary end point was the combined incidence of all-cause mortality, stroke, systemic emboli, and major bleeding event during a mean follow-up of 1 year. <b><i>Results:</i></b> There were 230 (30%) elderly patients, 151 patients were treated with warfarin, and 79 were treated with DE150. Fifty-two patients experienced the primary endpoint during the 1-year follow-up. Among the elderly, at 1-year of follow-up, the cumulative event rate of the combined endpoint in the DE150 and warfarin was 8.9 and 15.9% respectively (<i>p</i> = 0.14). After adjustment for age and gender, patients who were treated with DE150 had a nonsignificant difference in the risk for the combined end point as patients treated with warfarin both among the elderly and among the younger population (HR 0.58, 95% C.I = 0.25–1.39 and HR = 1.12, 95% C.I 0.62–2.00, respectively [<i>p</i> for age-group-by-treatment interaction = 0.83). <b><i>Conclusions:</i></b> Our results suggest that Dabigatran 150 mg twice a day can be safely used among elderly AF patients with low bleeding risk.

scholarly journals Development of SARS-CoV-2 Specific IgG and Virus-Neutralizing Antibodies after Infection with Variants of Concern or Vaccination

Vaccines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 700
Author(s):  
Franziska Neumann ◽  
Ruben Rose ◽  
Janine Römpke ◽  
Olaf Grobe ◽  
Thomas Lorentz ◽  
...  
Keyword(s):  
Immune Response ◽  
Receptor Binding ◽  
Neutralizing Antibodies ◽  
Neutralization Test ◽  
Vaccine Dose ◽  
High Avidity ◽  
Receptor Binding Domain ◽  
Robust Immune Response ◽  
Specific Igg ◽  
Nucleoprotein N

The humoral immunity after SARS-CoV-2 infection or vaccination was examined. Convalescent sera after infection with variants of concern (VOCs: B.1.1.7, n = 10; B.1.351, n = 1) and sera from 100 vaccinees (Pfizer/BioNTech, BNT162b2, n = 33; Moderna, mRNA-1273, n = 11; AstraZeneca, ChAdOx1 nCoV-19/AZD1222, n = 56) were tested for the presence of immunoglobulin G (IgG) directed against the viral spike (S)-protein, its receptor-binding domain (RBD), the nucleoprotein (N) and for virus-neutralizing antibodies (VNA). For the latter, surrogate assays (sVNT) and a Vero-cell based neutralization test (cVNT) were used. Maturity of IgG was determined by measuring the avidity in an immunoblot (IB). Past VOC infection resulted in a broad reactivity of anti-S IgG (100%), anti-RBD IgG (100%), and anti-N IgG (91%), while latter were absent in 99% of vaccinees. Starting approximately two weeks after the first vaccine dose, anti-S IgG (75–100%) and particularly anti-RBD IgG (98–100%) were detectable. After the second dose, their titers increased and were higher than in the convalescents. The sVNT showed evidence of VNA in 91% of convalescents and in 80–100%/100% after first/second vaccine dose, respectively. After the second dose, an increase in VNA titer and IgGs of high avidity were demonstrated by cVNT and IB, respectively. Re-vaccination contributes to a more robust immune response.

scholarly journals STABILITY OF DNA IN PURKINJE CELL NUCLEI OF THE MOUSE

1974 ◽  
Vol 63 (2) ◽  
pp. 665-674 ◽  
Author(s):  
V. Mareš ◽  
B. Schultze ◽  
W. Maurer
Keyword(s):  
Young Adult ◽  
Purkinje Cell ◽  
Nuclear Dna ◽  
Brain Regions ◽  
Nuclear Volume ◽  
High Dose ◽  
Prenatal Period ◽  
Cell Nuclei ◽  
Grain Number ◽  
Adult Mice

Neurons of the mouse were labeled with [3H]thymidine during their prenatal period of proliferation. The 3H activity of the Purkinje cell nuclei was then studied autoradiographically 8, 25, 55, and 90 days after birth. The measured grain number per nucleus decreased by about 14% between the 8th and 25th postnatal days and then remained constant up to 90 days. There was no significant decrease of the 3H activity of the Purkinje cell nuclei after correction of the measured grain number per nucleus for increasing nuclear volume of the growing Purkinje cells and for the influence of [3H]ß self-absorption in the material of the sections. Injection of a high dose of [3H]thymidine into young adult mice did not result in 3H labeling of either Purkinje or other neurons in other brain regions. The results agree with the concept of metabolic stability of nuclear DNA. "Metabolic" DNA could not be observed in these experiments.

Toxicity of high-dose flurazepam in the elderly

1977 ◽  
Vol 21 (3) ◽  
pp. 355-361 ◽  
Author(s):  
David J. Greenblatt ◽  
Marcia D. Allen ◽  
Richard I. Shader
Keyword(s):  
The Elderly ◽  
High Dose

E-clonal antibodies: selection of full-length IgG antibodies using bacterial periplasmic display

2008 ◽  
Vol 3 (11) ◽  
pp. 1766-1777 ◽  
Author(s):  
Yariv Mazor ◽  
Thomas Van Blarcom ◽  
Brent L Iverson ◽  
George Georgiou
Keyword(s):  
Full Length ◽  
Igg Antibodies ◽  
Selection Of

scholarly journals 480 Preliminary evaluation of a novel coronavirus vaccine (CORVax) using electroporation of plasmid DNA encoding a stabilized prefusion SARS-CoV-2 spike protein alone or with transfection of plasmid IL-12

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A514-A514
Author(s):  
Shawn Jensen ◽  
Christopher Twitty ◽  
Christopher Paustian ◽  
Madelein Laws ◽  
Glenna McDonnell ◽  
...  
Keyword(s):  
Immune Responses ◽  
Receptor Binding ◽  
Binding Domain ◽  
Tumor Rejection ◽  
Spike Protein ◽  
Preliminary Evaluation ◽  
List Type ◽  
Receptor Binding Domain ◽  
Igg Antibodies ◽  
Viral Neutralization

BackgroundSARS-CoV-2 (CoV2) has precipitated a global pandemic and the effectiveness of standard vaccine strategies to induce potent and persistent immunity to CoV2 is in question, particularly for the elderly. This problem is not dissimilar to what we have struggled with in our quest to induce immunity to cancer antigens, where vaccine-induced anti-cancer immune responses can be weak. Here, we describe a novel vaccine approach which leverages electroporation (EP) of a plasmid encoding a prefusion stabilized CoV2 spike protein (CORVax). As IL-12 has been shown to augment the efficacy of immunotherapy in aged mice,1 we have initiated studies to evaluate if plasmid IL-12 (TAVO™) can similarly augment anti-CoV2 immune responses in young mice and have planned studies in aged animals.MethodsA prefusion stabilized CoV2 spike plasmid expression vector was constructed, a master cell bank generated and clinical-grade plasmid manufactured. C57BL/6 and BALB/c were vaccinated via intramuscular (IM) and/or intradermal (ID) injection followed immediately by EP of plasmids encoding the CoV2 spike protein with or without plasmid-encoded murine IL-12 on days 1 and 14 or 21. Mice were followed for >120 days to assess safety. Splenocytes and serum were harvested at different time points to interrogate virus-specific cellular responses as well anti-spike IgG1/IgG2 antibody titers. A surrogate viral neutralization test (sVNT) assessed serum blockade of soluble hACE2R binding to immobilized CoV2 spike.ResultsPreliminary data shows that EP of CORVax alone or combined with IL-12 was safe. EP of CORVax was able to elicit anti-Spike IgG antibodies (IC50 = 1/2112), as well as IgG antibodies targeting the receptor binding domain of the Spike protein (IC50 = 1/965) approximately 40 days after the booster vaccination. In 2 of 2 experiments, CORVax combined with IL-12 significantly (P<0.0001) increased the sVNT titers at 2 months, but this benefit was lost by 3 months.ConclusionsEarly preclinical data shows that EP of CORVax can induce IgG responses to CoV2 Spike and the receptor binding domain (RBD) as well as apparent viral neutralizing activity. The addition of IL-12, at least transiently, increased sVNT titer. We plan to investigate alternate vaccine boosting strategies while extending these studies into aged animals and initiate a clinical trial in the near future.ReferencesRuby CE, Weinberg AD. OX40-Enhanced tumor rejection and effector T cell differentiation decreases with age. J Immunol2009;182:1481–9. https://doi.org/10.4049/jimmunol.182.3.1481.

Abstract 65: Restoration of Growth Differentiation Factor 11 Protects Against Stroke in Mice

Stroke ◽  
2016 ◽  
Vol 47 (suppl_1) ◽  
Author(s):  
Anjali Chauhan ◽  
Jacob Hudobenko ◽  
Anthony Patrizz ◽  
Louise D McCullough
Keyword(s):  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
The Elderly ◽  
Vehicle Group ◽  
Peripheral Tissues ◽  
Delayed Treatment ◽  
Aged Mice ◽  
Infarct Area ◽  
Age Related

Introduction: GDF 11 is a member of the transforming growth factor β superfamily. Loss of GDF11 occurs with aging and declining levels correlate with several detrimental age-associated phenotypes in both peripheral tissues and brain. Restoration of GDF11 enhances neurogenesis and cognitive function in aged mice. Brain expression of GDF11 has not been investigated after stroke. Stroke differentially affects the elderly. In this work we examined the role of GDF11 in aging, stroke and its potential utility as a neuroprotective agent. Methods: Male C57/BL6NCrl young (2-3 months) and aged (19-21) mice were used. Brain GDF11 expression was evaluated in young and aged mice by western blot. Focal ischemia was induced with a transient middle cerebral artery occlusion (MCAO). Mice were randomly assigned into two groups and were subjected to 90 min MCAO. Group 1 received vehicle (phosphate buffered saline) and group 2 was administered rGDF11 (100 ug/kg., ip) at the onset of ischemia. In additional experiments, the efficacy of delayed treatment (3 h after ischemia) with rGDF11 was tested. These mice were subjected to a 60 min MCAO. Mice were euthanized after 24 hours and 7 days respectively and brains were harvested to estimate infarct area. Results: A significant decrease in brain GDF11 levels was observed in aged mice as compared to young (p<0.05). Additionally, a significant decline in brain GDF11 expression was observed after stroke at 24 hours vs. sham groups (p<0.05). A significant decrease in cortical and hemispheric infarct area was observed in the rGDF11 group (cortical 48.73±1.05; hemisphere 49.68±3.58) as compared to vehicle group (60.54±4.88; 61.35±6.03), when GDF was administered at the time of ischemia. Delayed treatment with rGDF11 also reduced infarct at 7 days. Conclusions: Brain GDF11 levels decline with age and after stroke. Supplementation with rGDF11 ameliorates stroke induced injury in young mice at 24h and 7 days. These finding suggest potential role of GDF11 in age and stroke. Restoration of age-related loss of GDF may be a viable therapy for stroke.

scholarly journals Declining Levels of Neutralizing Antibodies Against SARS-CoV-2 in Convalescent COVID-19 Patients One Year Post Symptom Onset

2021 ◽  
Vol 12 ◽  
Author(s):  
Tiandan Xiang ◽  
Boyun Liang ◽  
Yaohui Fang ◽  
Sihong Lu ◽  
Sumeng Li ◽  
...  
Keyword(s):  
Symptom Onset ◽  
Neutralizing Antibodies ◽  
Natural Infection ◽  
Protein S ◽  
Igg Antibodies ◽  
Neutralizing Activity ◽  
Specific Igg ◽  
One Year ◽  
Kinetics Of

Major advances have been made in understanding the dynamics of humoral immunity briefly after the acute coronavirus disease 2019 (COVID-19). However, knowledge concerning long-term kinetics of antibody responses in convalescent patients is limited. During a one-year period post symptom onset, we longitudinally collected 162 samples from 76 patients and quantified IgM and IgG antibodies recognizing the nucleocapsid (N) protein or the receptor binding domain (RBD) of the spike protein (S). After one year, approximately 90% of recovered patients still had detectable SARS-CoV-2-specific IgG antibodies recognizing N and RBD-S. Intriguingly, neutralizing activity was only detectable in ~43% of patients. When neutralization tests against the E484K-mutated variant of concern (VOC) B.1.351 (initially identified in South Africa) were performed among patients who neutralize the original virus, the capacity to neutralize was even further diminished to 22.6% of donors. Despite declining N- and S-specific IgG titers, a considerable fraction of recovered patients had detectable neutralizing activity one year after infection. However, neutralizing capacities, in particular against an E484K-mutated VOC were only detectable in a minority of patients one year after symptomatic COVID-19. Our findings shed light on the kinetics of long-term immune responses after natural SARS-CoV-2 infection and argue for vaccinations of individuals who experienced a natural infection to protect against emerging VOC.

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