scholarly journals Long-Term Humoral Immune Response against SARS-CoV-2 after Natural Infection and Subsequent Vaccination According to WHO International Binding Antibody Units (BAU/mL)

Viruses ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2336
Author(s):  
Natalia Ruetalo ◽  
Bertram Flehmig ◽  
Michael Schindler ◽  
Lutz Pridzun ◽  
Angelika Haage ◽  
...  
Keyword(s):  
Natural Infection ◽  
Serum Samples ◽  
N Protein ◽  
Humoral Immune ◽  
Reference Preparation ◽  
Binding Antibody ◽  
One Year ◽  
Definition Of ◽  
The Individual

The new WHO reference standard allows for the definition of serum antibodies against various SARS-CoV-2 antigens in terms of binding antibody units (BAU/mL) and thus to compare the results of different ELISA systems. In this study, the concentration of antibodies (ABs) against both the S- and the N-protein of SARS-CoV-2 as well as serum neutralization activity were evaluated in three patients after a mild course of COVID-19. Serum samples were collected frequently during a period of over one year. Furthermore, in two individuals, the effects of an additional vaccination with a mRNA vaccine containing the S1-RBD sequence on these antibodies were examined. After natural infection, the antibodies (IgA, IgG) against the S1-protein remained elevated above the established cut-off to positivity (S-IgA 60 BAU/mL and S-IgG 50 BAU/mL, respectively) for over a year in all patients, while this was not the case for ABs against the N-protein (cut-off N-IgG 40 BAU/mL, N-IgA 256 BAU/mL). Sera from all patients retained the ability to neutralize SARS-CoV-2 for more than a year. Vaccination resulted in a rapid boost of antibodies to S1-protein but, as expected, not to the N-protein. Most likely, the wide use of the WHO reference preparation will be very useful in determining the individual immune status of patients after an infection with SARS-CoV-2 or after vaccination.

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.

scholarly journals Prime-boost vaccination regimens with INO-4800 and INO-4802 augment and broaden immune responses against SARS-CoV-2 in nonhuman primates

2021 ◽  
Author(s):  
Jewell N Walters ◽  
Blake Schouest ◽  
Ami Patel ◽  
Emma L Reuschel ◽  
Katherine Schultheis ◽  
...  
Keyword(s):  
Dna Vaccine ◽  
Nonhuman Primates ◽  
First Generation ◽  
Rhesus Macaques ◽  
Natural Infection ◽  
Next Generation ◽  
Synthetic Dna ◽  
One Year ◽  
Global Population

The enhanced transmissibility and immune evasion associated with emerging SARS-CoV-2 variants demands the development of next-generation vaccines capable of inducing superior protection amid a shifting pandemic landscape. Since a portion of the global population harbors some level of immunity from vaccines based on the original Wuhan-Hu-1 SARS-CoV-2 sequence or natural infection, an important question going forward is whether this immunity can be boosted by next-generation vaccines that target emerging variants while simultaneously maintaining long-term protection against existing strains. Here, we evaluated the immunogenicity of INO-4800, our synthetic DNA vaccine candidate for COVID-19 currently in clinical evaluation, and INO-4802, a next-generation DNA vaccine designed to broadly target emerging SARS-CoV-2 variants, as booster vaccines in nonhuman primates. Rhesus macaques primed over one year prior with the first-generation INO-4800 vaccine were boosted with either INO-4800 or INO-4802 in homologous or heterologous prime-boost regimens. Both boosting schedules led to an expansion of antibody responses which were characterized by improved neutralizing and ACE2 blocking activity across wild-type SARS-CoV-2 as well as multiple variants of concern. These data illustrate the durability of immunity following vaccination with INO-4800 and additionally support the use of either INO-4800 or INO-4802 in prime-boost regimens.

scholarly journals Distinct age-specific SARS-CoV-2 IgG decay kinetics following natural infection

2021 ◽  
Author(s):  
Calvin P Sjaarda ◽  
Emily Moslinger ◽  
Kyla Tozer ◽  
Robert I Colautti ◽  
Samira Kheitan ◽  
...  
Keyword(s):  
Natural Infection ◽  
Decay Rates ◽  
Decay Kinetics ◽  
Serum Samples ◽  
Igg Antibody ◽  
Multi Centre Study ◽  
Viral Neutralization ◽  
Antibody Levels ◽  
Over Time

Background. Antibody responses to SARS-CoV-2 can be observed as early as 14 days post- infection, but little is known about the stability of antibody levels over time. Here we evaluate the long-term stability of anti-SARS-CoV-2 IgG antibodies following infection in 402 adult donors. Methods. We performed a multi-centre study carried out at Plasma Donor Centres in the city of Heidelberg (Plasmazentrum Heidelberg, Germany) and Munich (Plasmazentrum M&uumlnchen, Germany). We present anti-S/N and anti-N IgG antibody levels in prospective serum samples collected up to 403 days post recovery from SARS-CoV-2 infected individuals. Results: The cohort includes 402 adult donors (185 female, 217 male; 17 - 68 years of age) where anti-SARS-CoV-2 IgG levels were measured in plasma samples collected between 18- and 403-days post SARS-CoV-2 infection. A linear mixed effects model demonstrated IgG decay rates that decrease over time (χ2=176.8, p<0.00001) and an interaction of time*age (χ2=10.0, p<0.005)), with those over 60+ years showing the highest baseline IgG levels and the fastest rate of IgG decay. Baseline viral neutralization assays demonstrated that serum IgG levels correlated with in vitro neutralization capacity in 91% of our cohort. Conclusion. Long-term antibody levels and age-specific antibody decay rates suggest the potential need for age-specific vaccine booster guidelines to ensure long term vaccine protection against SARS-CoV-2 infection.

Organizational knowledge transfer: creating new knowledge from old knowledge

2014 ◽  
Author(s):  
Rui Moura ◽  
Álvaro Dias ◽  
Célia Quintas ◽  
Dilar Costa
Keyword(s):  
Knowledge Transfer ◽  
Explicit Knowledge ◽  
Knowledge Society ◽  
Social Transformations ◽  
Personal Belief ◽  
New Knowledge ◽  
Definition Of ◽  
The Individual ◽  
Business Competitiveness

The definition of knowledge supported by Nonakae Takeuchi (1995) considers that it is a human process that allows justifying personal belief about the truth. The individual is an integral part and is inseparable from knowledge. The authors also distinguish explicit knowledge, which can be expressed in words and numbers, and tacit knowledge, that is held by the individual in the form of know-how, and can be identified through their habits, behaviors, emotions, values and ideas.However, there is a wealth of professional knowledge in qualified people that are apart from active life voluntarily or involuntarily, through unemployment or retirement. This source of knowledge could be (re)transformed into new sources of competitiveness for organizations.In this context, this paper seeks to present the results of an exploratory study, orientated to identify knowledge transfer processes, from pensioners and long-term unemployed, to business professionals and companies, through the adaptation of mentoring programs. Five thematic areas of knowledge transfer were considered and selected as key areas of organizational competitiveness: Entrepreneurship, Innovation, Cooperation, Distribution, and Exportation.We consider this work relevant to the extent that the processes of change, caused by world crisis, tend to split fundamental knowledge that must be preserved. With the emergence of the knowledge society, we face problems, uncertainties and challenges arising not only from the financial crises and economic recessions, but also from the social transformations that we have seen in the processes of globalization, demographic change, technological revolution and the single currency, among others.The various transformations mentioned have produced paradoxical impacts, in particular job and knowledge management and the organization of work and working time. Such changes imply that researchers find new ways to a more holistic and human-centered organization.To realize our study we constructed a methodology of knowledge transfer, largely inspired by the work of Peet, Walsh, Rawak & Sober (2010).Our methodology comprised several steps: ( a) identify the knowledge, ( b ) access to persons owning knowledge, ( c ) integrating knowledge in projects, ( d ) combine ideas and initiatives, (e ) relaying knowledge, ( f ) enhance and apply knowledge.The experiential processes developed under this study give companies a large potential to be able to achieve their change objectives, incorporate new knowledge and increase their competitiveness. In this vein, we concluded that our methodology of knowledge transfer was effective as a mean for learning and to operationalize the knowledge held by mentors in strategic areas in the field of entrepreneurship, innovation and cooperation. We also concluded, by the duration of the project and through the measurement of the effects of knowledge transfer and its return in terms of effective improvement of business competitiveness, that it must be applied on a time scale projected in the medium and long term.

scholarly journals SARS-CoV-2 infection induces sustained humoral immune responses in convalescent patients following symptomatic COVID-19

2020 ◽  
Author(s):  
Jun Wu ◽  
Boyun Liang ◽  
Cunrong Chen ◽  
Hua Wang ◽  
Yaohui Fang ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
Disease Onset ◽  
Immunoglobulin M ◽  
Late Time ◽  
N Protein ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
First World ◽  
Observation Period

Long-term antibody responses and neutralizing activities following SARS-CoV-2 infections have not yet been elucidated. We quantified immunoglobulin M (IgM) and G (IgG) antibodies recognizing the SARS-CoV-2 receptor-binding domain (RBD) of the spike (S) or the nucleocapsid (N) protein, and neutralizing antibodies during a period of six months following COVID-19 disease onset in 349 symptomatic COVID-19 patients, which were among the first world-wide being infected. The positivity rate and magnitude of IgM-S and IgG-N responses increased rapidly. High levels of IgM-S/N and IgG-S/N at 2-3 weeks after disease onset were associated with virus control and IgG-S titers correlated closely with the capacity to neutralize SARS-CoV-2. While specific IgM-S/N became undetectable 12 weeks after disease onset in most patients, IgG-S/N titers showed an intermediate contraction phase, but stabilized at relatively high levels over the six months observation period. At late time points the positivity rates for binding and neutralizing SARS-CoV-2-specific antibodies was still over 70%. Taken together, our data indicate sustained humoral immunity in recovered patients who suffer from symptomatic COVID-19, suggesting prolonged immunity.

scholarly journals Effects of Environmental Factors and Cultural Practices on Bull's Eye Rot of Pear

Plant Disease ◽  
2008 ◽  
Vol 92 (3) ◽  
pp. 421-424 ◽  
Author(s):  
Jose L. Henriquez ◽  
David Sugar ◽  
Robert A. Spotts
Keyword(s):  
Environmental Factors ◽  
Cultural Practices ◽  
Natural Infection ◽  
Effect Of Temperature ◽  
Growing Seasons ◽  
Long Term Storage ◽  
One Year ◽  
Bull's Eye ◽  
Term Storage

Bull's eye rot of pome fruits caused by Neofabraea spp. is characterized by infection occurring in the orchard throughout the growing season whereas rot lesions develop during long-term storage after harvest. Bull's eye rot was observed on pear fruit exposed to natural infection for any of six to nine sequential 1-to-2-week exposure periods during two growing seasons. Highest infection levels were associated with exposure closest to harvest. Over-tree irrigation and late harvest resulted in higher bull's eye rot incidence than under-tree irrigation and early or mid-season harvest. Fruit were inoculated prior to harvest with Neofabraea perennans to determine the effect of environmental factors on the development of bull's eye rot. The effect of temperature was inconsistent; disease was greatest at 10°C in one year of study but greatest at 30°C in the second year. Bull's eye rot developed independently of wetness durations longer than 0.5 h.

scholarly journals Effectiveness of Group vs. Individual Therapy to Decrease Peer Problems and Increase Prosociality in Children

2021 ◽  
Vol 18 (8) ◽  
pp. 3950
Author(s):  
Silvia Melero ◽  
Alexandra Morales ◽  
José P. Espada ◽  
Xavier Méndez ◽  
Mireia Orgilés
Keyword(s):  
Peer Relationships ◽  
Social Acceptance ◽  
Individual Therapy ◽  
Prosocial Behaviors ◽  
Peer Problems ◽  
Group Format ◽  
Ssl Protocol ◽  
One Year ◽  
The Individual

Emotional difficulties in children are often shown to be associated with peer problems and low prosocial behaviors. Super Skills for Life (SSL) is a transdiagnostic protocol for the prevention of emotional problems in children and has also obtained improvements of other comorbid symptoms. This study aimed at comparing the effects of SSL in reducing peer problems and increasing prosocial behaviors in children aged 8 to 12 years between the group and the individual modalities. For this purpose, 140 children (35% girls) received the program, 70 in group format and 70 in individual format, and were evaluated at the baseline, posttest, and after one year. Both modalities were effective in enhancing social relationships in children, although the individual modality showed more promising results. Children belonging to the individual modality group presented fewer peer problems (less social isolation and rejection, greater social acceptance, more friends) and greater prosocial behaviors (helping, empathy, kindness, and sharing) compared to children receiving the therapy in group modality, both in the short and in the long term. In conclusion, this study provides evidence of SSL protocol efficacy for improving children’s peer relationships and prosocial behaviors and encourages the implementation of transdiagnostic interventions in both clinical and educational settings.

scholarly journals SARS-CoV-2 infection induces sustained humoral immune responses in convalescent patients following symptomatic COVID-19

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jun Wu ◽  
Boyun Liang ◽  
Cunrong Chen ◽  
Hua Wang ◽  
Yaohui Fang ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
Disease Onset ◽  
Immunoglobulin M ◽  
Late Time ◽  
N Protein ◽  
Contraction Phase ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
Observation Period

AbstractLong-term antibody responses and neutralizing activities in response to SARS-CoV-2 infection are not yet clear. Here we quantify immunoglobulin M (IgM) and G (IgG) antibodies recognizing the SARS-CoV-2 receptor-binding domain (RBD) of the spike (S) or the nucleocapsid (N) protein, and neutralizing antibodies during a period of 6 months from COVID-19 disease onset in 349 symptomatic COVID-19 patients who were among the first be infected world-wide. The positivity rate and magnitude of IgM-S and IgG-N responses increase rapidly. High levels of IgM-S/N and IgG-S/N at 2-3 weeks after disease onset are associated with virus control and IgG-S titers correlate closely with the capacity to neutralize SARS-CoV-2. Although specific IgM-S/N become undetectable 12 weeks after disease onset in most patients, IgG-S/N titers have an intermediate contraction phase, but stabilize at relatively high levels over the 6 month observation period. At late time points, the positivity rates for binding and neutralizing SARS-CoV-2-specific antibodies are still >70%. These data indicate sustained humoral immunity in recovered patients who had symptomatic COVID-19, suggesting prolonged immunity.

scholarly journals Antibody Response against the SARS-CoV-2 Nucleocapsid Protein and Its Subdomains—Identification of Pre-Immunization Status by Human Coronaviruses with Multipanel Nucleocapsid Fragment Immunoblotting

COVID ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 105-114
Author(s):  
Sahra Pajenda ◽  
Sebastian Kapps ◽  
Thomas Reiter ◽  
Raimundo Freire ◽  
Veronique A. J. Smits ◽  
...  
Keyword(s):  
Nucleocapsid Protein ◽  
Posterior Part ◽  
Rapid Identification ◽  
Diagnostic Methods ◽  
Serum Samples ◽  
N Protein ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
Global Pandemic ◽  
Human Coronaviruses

A novel beta coronavirus that emerged in late December 2019 triggered a global pandemic. Diagnostic methods for rapid identification of infected individuals were established in new biotechnological approaches. Vaccine production and application to individuals and measurement of SARS-CoV-2 antibodies also began. Serum samples from 240 health care workers were collected at three-month intervals over nine months. Indirect SARS-CoV-2 nucleocapsid IgG ELISA tests were used to identify humoral immune responses. All seropositive individuals and those with borderline ELISA values were tested with a specifically generated multipanel nucleocapsid fragment immunoblot. Of the 240 individuals, 24 showed seroconversion in ELISA after experiencing COVID-19. All of them showed a positive reaction against the full-length nucleocapsid protein in the immunoblot. The highest reactivity was seen either against fragment N(100–300) or in a minority against the posterior part N(200–419). In general, the staining pattern of COVID-19 patients showed four phenotypes. In contrast, three individuals classified as borderline by ELISA reacted exclusively with fragments N(1–220) and N(100–300) containing the octamer amino acid sequence FYYLGTGP, which is identical in human coronaviruses sharing this sequence with SARS-CoV-2. These represent a unique and thus fifth phenotype. This work suggests the existence of distinct phenotypic patterns of IgG production towards N-protein subdomains.

scholarly journals SARS-CoV-2 antibodies remain detectable 12 months after infection and antibody magnitude is associated with age and COVID-19 severity

2021 ◽  
Author(s):  
Eric D. Laing ◽  
Nusrat J. Epsi ◽  
Stephanie A. Richard ◽  
Emily C. Samuels ◽  
Wei Wang ◽  
...  
Keyword(s):  
Symptom Onset ◽  
Neutralizing Antibodies ◽  
Natural Infection ◽  
Geometric Mean ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Serum Samples ◽  
Military Hospitals ◽  
Igg Binding ◽  
One Year

ABSTRACTImportanceThe persistence of SARS-CoV-2 antibodies may be a predictive correlate of protection for both natural infections and vaccinations. Identifying predictors of robust antibody responses is important to evaluate the risk of re-infection / vaccine failure and may be translatable to vaccine effectiveness.ObjectiveTo 1) determine the durability of anti-SARS-CoV-2 IgG and neutralizing antibodies in subjects who experienced mild and moderate to severe COVID-19, and 2) to evaluate the correlation of age and IgG responses to both endemic human seasonal coronaviruses (HCoVs) and SARS-CoV-2 according to infection outcome.DesignLongitudinal serum samples were collected from PCR-confirmed SARS-CoV-2 positive participants (U.S. active duty service members, dependents and military retirees, including a range of ages and demographics) who sought medical treatment at seven U.S. military hospitals from March 2020 to March 2021 and enrolled in a prospective observational cohort study.ResultsWe observed SARS-CoV-2 seropositivity in 100% of inpatients followed for six months (58/58) to one year (8/8), while we observed seroreversion in 5% (9/192) of outpatients six to ten months after symptom onset, and 18% (2/11) of outpatients followed for one year. Both outpatient and inpatient anti-SARS-CoV-2 binding-IgG responses had a half-life (T1/2) of >1000 days post-symptom onset. The magnitude of neutralizing antibodies (geometric mean titer, inpatients: 378 [246-580, 95% CI] versus outpatients: 83 [59-116, 95% CI]) and durability (inpatients: 65 [43-98, 95% CI] versus outpatients: 33 [26-40, 95% CI]) were associated with COVID-19 severity. Older age was a positive correlate with both higher IgG binding and neutralizing antibody levels when controlling for COVID-19 hospitalization status. We found no significant relationships between HCoV antibody responses and COVID-19 clinical outcomes, or the development of SARS-CoV-2 neutralizing antibodies.Conclusions and RelevanceThis study demonstrates that humoral responses to SARS-CoV-2 infection are robust on longer time-scales, including those arising from milder infections.However, the magnitude and durability of the antibody response after natural infection was lower and more variable in younger participants who did not require hospitalization for COVID-19. These findings support vaccination against SARS-CoV-2 in all suitable populations including those individuals that have recovered from natural infection.

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