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1.
Dokl Biochem Biophys ; 503(1):90-92, 2022.
Article in English | PubMed | ID: covidwho-1832372

ABSTRACT

Seven amino acid sequences of antibody mimetics molecules, monobodies, capable of interacting with the nucleocapsid protein of the SARS-CoV virus, were taken from the literature. Nucleotide sequences of monobody genes were obtained by gene synthesis, which were expressed in E. coli and isolated using Ni-NTA chromatography. It was shown by thermophoresis that three of the seven selected antibody-like molecules can interact with high affinity (dissociation constant of tens of nM) with the nucleocapsid protein of the SARS-CoV-2 virus. For the remaining four monobodies, only low affinity binding with a dissociation constant of several μM was found.

2.
Laboratory Medicine ; 53(3):314-319, 2022.
Article in English | MEDLINE | ID: covidwho-1831243

ABSTRACT

OBJECTIVE: Determine the COVID-19 seroconversion rate for patients with multiple myeloma receiving a COVID-19 vaccine. MATERIALS AND METHODS: After 45 patients received their second COVID-19 vaccine dose, their serum IgG antibodies were measured: 22 with monoclonal gammopathy (MG) of unknown significance, 3 with smoldering myeloma, 2 with light chain amyloidosis, and 18 with MG (9 in remission, 6 out of remission, and 3 with free light-chain gammopathy alone). A second serum specimen was retained for 16 patients with MG. Their antibody levels were compared to those of 78 uninfected healthy vaccinated control patients. RESULTS: Three patients with MG had low antibody levels on blood collected 98, 100, and 113 days after the initial vaccine dose (2 with MG of unknown significance and 1 with hypogammaglobulemia). The other 40 patients with MG (seroconversion rate 93%) and both patients with amyloidosis produced antibodies. Relative to days after vaccination, patients with MG had lower antibody levels than control patients. CONCLUSION: After receiving a COVID-19 vaccine, most patients with MG produce anti-SARS-CoV-2 antibodies comparable to levels in uninfected vaccinated healthy control patients.

3.
Embase; 2022.
Preprint in English | EMBASE | ID: ppcovidwho-334871

ABSTRACT

The emerging SARS-CoV-2 variants of concern (VOCs) exhibit enhanced transmission and immune escape, reducing the efficacy and effectiveness of the two FDA-approved mRNA vaccines. Here, we explored various strategies to develop novel mRNAs vaccines to achieve safer and wider coverage of VOCs. Firstly, we constructed a cohort of mRNAs that feature a furin cleavage mutation in the spike (S) protein of predominant VOCs, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1) and Delta (B.1.617.2). Not present in the mRNA vaccines currently in use, the mutation abolished the cleavage between the S1 and S2 subunits, potentially enhancing the safety profile of the immunogen. Secondly, we systematically evaluated the induction of neutralizing antibodies (nAb) in vaccinated mice, and discovered that individual VOC mRNAs elicited strong neutralizing activity in a VOC-specific manner. Thirdly, the IgG produced in mice immunized with Beta-Furin and Washington (WA)-Furin mRNAs showed potent cross-reactivity with other VOCs, which was further corroborated by challenging vaccinated mice with the live virus of VOCs. However, neither WA-Furin nor Beta-Furin mRNA elicited strong neutralizing activity against the Omicron variant. Hence, we further developed an Omicron-specific mRNA vaccine that restored protection against the original and the sublineages of Omicron variant. Finally, to broaden the protection spectrum of the new Omicron mRNA vaccine, we tested the concept of bivalent immunogen. Instead of just fusing two RBDs head-to-tail, we for the first time constructed an mRNA-based chimeric immunogen by introducing the RBD of Delta variant into the entire S antigen of Omicron. The resultant chimeric mRNA was capable of inducing potent and broadly acting nAb against Omicron (both BA.1 and BA.2) and Delta, which paves the way to develop new vaccine candidate to target emerging variants in the future.

4.
Embase; 2022.
Preprint in English | EMBASE | ID: ppcovidwho-334805

ABSTRACT

Omicron sub-lineage BA.2 has rapidly surged globally, accounting for over 60% of recent SARS-CoV-2 infections. Newly acquired RBD mutations and high transmission advantage over BA.1 urge the investigation of BA.2's immune evasion capability. Here, we show that BA.2 causes strong neutralization resistance, comparable to BA.1, in vaccinated individuals' plasma. However, BA.2 displays more severe antibody evasion in BA.1 convalescents, and most prominently, in vaccinated SARS convalescents' plasma, suggesting a substantial antigenicity difference between BA.2 and BA.1. To specify, we determined the escaping mutation profiles1,2 of 714 SARS-CoV-2 RBD neutralizing antibodies, including 241 broad sarbecovirus neutralizing antibodies isolated from SARS convalescents, and measured their neutralization efficacy against BA.1, BA.1.1, BA.2. Importantly, BA.2 specifically induces large-scale escape of BA.1/BA.1.1effective broad sarbecovirus neutralizing antibodies via novel mutations T376A, D405N, and R408S. These sites were highly conserved across sarbecoviruses, suggesting that Omicron BA.2 arose from immune pressure selection instead of zoonotic spillover. Moreover, BA.2 reduces the efficacy of S309 (Sotrovimab)3,4 and broad sarbecovirus neutralizing antibodies targeting the similar epitope region, including BD55-5840. Structural comparisons of BD55-5840 in complexes with BA.1 and BA.2 spike suggest that BA.2 could hinder antibody binding through S371F-induced N343-glycan displacement. Intriguingly, the absence of G446S mutation in BA.2 enabled a proportion of 440-449 linear epitope targeting antibodies to retain neutralizing efficacy, including COV2-2130 (Cilgavimab)5. Together, we showed that BA.2 exhibits distinct antigenicity compared to BA.1 and provided a comprehensive profile of SARS-CoV-2 antibody escaping mutations. Our study offers critical insights into the humoral immune evading mechanism of current and future variants.

5.
Embase; 2021.
Preprint in English | EMBASE | ID: ppcovidwho-334677

ABSTRACT

We conducted preclinical studies in mice using a yeast-produced SARS-CoV-2 RBD subunit vaccine candidate formulated with aluminum hydroxide (alum) and CpG deoxynucleotides. This formulation is equivalent to the CorbevaxTM vaccine that recently received emergency use authorization by the Drugs Controller General of India. We compared the immune response of mice vaccinated with RBD/alum to mice vaccinated with RBD/alum+CpG. We also evaluated mice immunized with RBD/alum+CpG and boosted with RBD/alum. Mice were immunized twice intramuscularly at a 21-day interval. Compared to two doses of the/alum formulation, the RBD/alum+CpG vaccine induced a stronger and more balanced Th1/Th2 cellular immune response, with high levels of neutralizing antibodies against the original Wuhan isolate of SARS-CoV-2 as well as the B.1.1.7 (Alpha), B.1.351 (Beta), B.1.617.2 and (Delta) variants. Neutralizing antibody titers against the B.1.1.529 (BA.1, Omicron) variant exceeded those in human convalescent plasma after Wuhan infection but were lower than against the other variants. Interestingly, the second dose did not benefit from the addition of CpG, possibly allowing dose-sparing of the adjuvant in the future. The data reported here reinforces that the RBD/alum+CpG vaccine formulation is suitable for inducing broadly neutralizing antibodies against SARS-CoV-2 including variants of concern.

6.
Embase; 2021.
Preprint in English | EMBASE | ID: ppcovidwho-334613

ABSTRACT

The spread of SARS-CoV-2 has led to a devastating pandemic, with infections resulting in a range of symptoms collectively known as COVID-19. The full repertoire of human tissues and organs susceptible to infection is an area of active investigation, and some studies have implicated the reproductive system. The effects of COVID-19 on human reproduction remain poorly understood, and particularly the impact on early embryogenesis and establishment of a pregnancy are not known. In this work, we explore the susceptibility of early human embryos to SARS-CoV-2 infection. We note that ACE2 and TMPRSS2, two canonical cell entry factors for SARS-CoV-2, are co-expressed in cells of the trophectoderm in blastocyst-stage preimplantation embryos. Using fluorescent reporter virions pseudotyped with Spike (S) glycoprotein from SARSCoV-2, we observe robust infection of trophectoderm cells, and this permissiveness could be attenuated with blocking antibodies targeting S or ACE2. When exposing human blastocysts to the live, fully infectious SARS-CoV-2, we detected cases of infection that compromised embryo health. Therefore, we identify a new human target tissue for SARS-CoV-2 with potential medical implications for reproductive health during the COVID-19 pandemic and its aftermath.

7.
Microchemical Journal ; 178:178, 2022.
Article in English | GIM | ID: covidwho-1829251

ABSTRACT

Ebola virus (EBOV) outbreaks have been reported to be the most severe mortally recurrent illness due to a lack of timely diagnosis and medication. EBOV disease is a severe syndrome of hemorrhagic viral fever caused by the EBOV, is spread directly in contact with infected body fluids and virus-contaminated or animal-affected objects. Individuals typically die before antibody response at the point of fatal EBOV infection. Currently, prognosis includes a combination of case identification and lab tests, typically real-time PCR or reverse transcription to diagnose viral RNA or rapid immunoassay-based detection methods to identify EBOV antigens. Moreover, few nanotech-based ways have lately been identified to diagnose the Ebola virus. Optical monitoring, in particular, permits fluorescence molecules to be recognized with the naked eye or fluorometers. Also, electrochemical identification methods (either amperometry, potentiometric, or impedimetric) could provide a susceptible system utilizing disposable lab on chips. Furthermore, the electrochemical devices may be easily miniaturized using a hand-held potentiostat, eliminating the need for complicated diagnostic tools. Advances in technology have also been coupled with growing attempts to improve the capacity for decentralized diagnostic identification that can be used near the patient care level. Infectious illness outbreaks can be contained more easily with timely identification and treatment optimization. Currently, technical advancements in artificial intelligence (AI) and the internet of medical things(IoMT) are being used to assist such POCT. Therefore, IoMT provides wireless-based operation & interconnection of POCT devices to health experts & medical care centers. POCT systems with IoMT can bridge the gap between bioinformatics generation, quick analysis & clinical validation. An optimal IoMT-POCT will aid in determining the development of the disease, making treatment recommendations, and assessing prescribed therapy's efficiency. This review illustrates some conventional strategies for diagnosing Ebola & advocates for a fast, accurate, and responsive point of care identification of EBOV for massive health care.

8.
Case Reports in Dermatology ; 14(1):1-5, 2022.
Article in English | ProQuest Central | ID: covidwho-1824228

ABSTRACT

The clinical presentation of dermatomyositis (DM) is diverse, with varied phenotypes that may be correlated with specific autoantibodies. The anti-melanoma differentiation-associated gene 5 (MDA5) antibody in DM is associated with an amyopathic phenotype of DM, with several unusual cutaneous manifestation and increased risk for rapidly progressive interstitial lung disease. Initial presentation may be subtle, but early diagnosis is key to initiation of proper immunosuppressive therapy. In this report, we describe perinasal edema and erythema as a presenting complaint of anti-MDA5 DM in an otherwise healthy 40-year-old woman. The edema began shortly after heavy sun exposure and was followed by painful papules in her hands and arthritis within a few weeks. She was found to have high titer of anti-CCP and anti-MDA5, and thus was diagnosed with DM and rheumatoid arthritis overlap. A CT chest, abdomen, and pelvis showed patchy ground-glass and interstitial opacities in bilateral lower lobes consistent with mild interstitial lung disease without evidence of malignancy. Perinasal cutaneous findings and arthralgias improved with initiation of prednisone. To our knowledge, this is the first report of perinasal edema as a presenting symptom for DM and should raise suspicion for MDA-5 disease.

9.
Journal of Advances in Medical and Biomedical Research ; 30(139):75-85, 2022.
Article in English | EMBASE | ID: covidwho-1822722

ABSTRACT

Novel coronavirus causes the outbreak of COVID-19. There is still no verified treatment regimen against this novel virus;however, different drugs and compounds have been tested against it. Ample proposals have led to a good understanding of pathogenesis and drug efficacy against the novel virus disease. Excess systemic inflammation, which is described as cytokine storm, in the severe cases of COVID-19 can pass through the blood-brain barrier, enter the brain tissue, and activate the microglial cells and oligodenritcytes. Activation of the microglia cells and oligodenritcytes can increase generation of reactive oxygen species in the brain. Excess generation of reactive oxygen species can in turn increase neuro-inflammation in some cases of patients with COVID-19. Treatment of COVID-19 is far from clear. Today, some antiviral drugs such as remdisivir, favipiravir, ribavirin, kaletra, and arbidol are being tested against the disease. Besides these drugs, corticosteroids, anti-malaria drugs (such as chloroquine family), anticoagulants (such as heparin or enoxaparin) are repurposed. In this paper, first we explained the pathogenesis of COVID-19 particles, particularly in the brain. Second, we reviewed recent treatment options up to now, including interferon therapy, convalescent plasma exchange, plasmapheresis, immunoglobin therapy, and use of specified monoclonal anti-bodies in COVID-19 patients.

10.
Cureus Journal of Medical Science ; 14(4):5, 2022.
Article in English | Web of Science | ID: covidwho-1822590

ABSTRACT

The coronavirus disease 2019 (COVID-19) includes an extensive spectrum of clinical manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Previous studies have shown that SARS-CoV-2 often exhibits central nervous system (CNS) manifestations, including encephalitis, meningitis, and spinal cord pathologies. To date, few cases of COVID-19-associated transverse myelitis (TM) have been described. A 40-year-old unvaccinated man with no significant medical history presented to the emergency department complaining of fever, worsening burning sensation in his lower extremities, unsteady gait, and difficulty initiating urination for five days. Twelve days before presentation, the patient had tested positive for SARS-CoV-2 infection. Physical examination revealed hyperesthesia, starting around the nipple line (T4) and extending distally, involving the lower extremities, accompanied by symmetric weakness in the lower extremities. Magnetic resonance imaging of the thoracic spine with and without contrast revealed mild intramedullary signal abnormality at T3-T4 and T6-T8, confirming the suspicion of TM. Further laboratory testing revealed a C-reactive protein level of 67 mg/L, lactate dehydrogenase level of 181 mg/L, serum B12 level of 781 pg/mL, methylmalonic acid level of 165 nmol/L, folate of >24.5 ng/mL, and thyroid-stimulating hormone level of 0.481 mu IU/L. Lumbar puncture was performed, and cerebrospinal fluid analysis revealed a cell count of 14 cells/mu L, with 69% lymphocytes, glucose level of 81 mg/dL, protein level of 32 mg/dL, and negative cultures. Human immunodeficiency virus, antinuclear antibody screening, anti-DNA, rapid plasma reagin, Lyme serology, anti-SSA, and anti-SSB antibodies were unremarkable. Serum aquaporin-4 immunoglobulin G was negative, and myelin oligodendrocyte glycoprotein (MOG) antibodies were positive. The patient was treated with intravenous methylprednisolone and oral gabapentin and was discharged after five days when his urinary retention improved. Most previously reported cases of COVID-19-related TM were negative for autoimmune workup. Although the exact pathophysiology of COVID-19-related TM remains unclear, one hypothesis suggests that it is a consequence of the direct viral invasion. However, our patient had MOG antibodies, suggesting the possible involvement of a different mechanism. In MOG-associated TM, it has been suggested that MOG antibodies gain access to the CNS through disruption of the blood-brain barrier. This unique presentation demonstrates that further studies are needed to understand the effects of SA RSCoV-2 infection on the immune and nervous systems. It also highlights that young and otherwise healthy patients are at risk of severe COVID-19-related complications, including CNS disorders.

11.
Journal of Clinical Neonatology ; 11(2):65-70, 2022.
Article in English | EMBASE | ID: covidwho-1822508

ABSTRACT

Background: Multisystem inflammatory syndrome in children (MIS-C) is a well-known entity that occurs 3-4 weeks after COVID-19. A similar entity in newborns, known as Multisystem Inflammatory Syndrome in Newborns (MIS-N), is also described. However, the epidemiology, case definition, clinical presentations, and outcomes of MIS-N are still being updated. The presence of SARS CoV 2 antibodies in both the mother and the neonate suggests transplacental transfer of IgG antibodies causing cytokine storm and multisystem inflammatory syndrome in newborns (MIS-N). Aims and Objectives: To investigate the clinical characteristics, laboratory parameters, outcomes, and treatment modalities of neonates with multisystem inflammatory syndrome due to transplacental transfer of SARS CoV 2 antibodies. Materials and Methods: The study included eighteen consecutive neonates who met the MIS-C criteria. Following prior ethical clearance and consent from parents or guardians, socio-demographic data, lab parameters, clinical parameters, and treatment given were documented, tabulated, and analysed. Results: All of the 18 neonates had fever. The most common system involved was the respiratory system (15/18), followed by the cardiovascular system with coronary artery dilatations (10/18) and persistent pulmonary hypertension (4/18). All 17 cases (17/18) responded favourably to intravenous immunoglobulins (2 gm/kg) and intravenous dexamethasone (0.15 mg/kg). D-Dimers decreased significantly after treatment, with a p value of 0.01. One case with more than three systems involved (respiratory, CVS, CNS, and renal involvement) (1/18) resulted in death. Conclusion: A high index of suspicion is warranted in critically ill neonates, especially with fever, multisystem involvement and positive SARS CoV 2 antibodies. Fever may be a soft pointer to the diagnosis as fever is rare in neonates with other illnesses. Followup antibody titres are needed to document if there is any relationship between level of antibodies and disease. Safety of vaccination also needs to be addressed as antibodies are implicated in the etiopathogenesis of MIS-N.

12.
Journal of Radiology Case Reports ; 2022(2):12-20, 2022.
Article in English | EMBASE | ID: covidwho-1822480

ABSTRACT

IgG4-related disease is an autoimmune condition that results in inflammation and fibrosis throughout multiple organ systems. This disease is rare;however, it can mimic many more prevalent conditions clinically and thus should be included in their differential diagnoses. Although autoimmune pancreatitis is the most common abdominal manifestation, the disease can afflict the hepatobiliary, vascular and renal systems as well. We present a case of a 78-year-old male with symptoms of chronic fatigue and weight loss. Imaging was performed with the expectation of revealing a malignancy, although the features of IgG4-related disease involving multiple organs were detected instead. Serology confirmed the diagnosis. It is imperative to diagnose IgG4-related disease early as it has a different treatment and favorable prognosis compared to many malignancies.

13.
Vaccines ; 10(4), 2022.
Article in English | EMBASE | ID: covidwho-1822475

ABSTRACT

Background: Longitudinal surveys to monitor the seroprevalence are required to support efforts for assessment of the levels of endemic stability in certain countries. We investigated seroprevalence of anti-SARS-CoV-2-S1 receptor-binding domain (RBD)-specific antibodies in the serum samples in 2011–2021, including a cohort study of 2019–2021, to evaluate the vaccination and anti-IgG-SARS-CoV-2–S1 RBD-positive statuses to assess the resistance and severity of COVID-19. Materials and Methods: Anti-SARS-CoV-2-S1 RBD-specific antibodies were assayed in the serum samples (N = 565) randomly selected from various cohorts previously recruited from 2011 to 2021 from the city of Moscow and Moscow Region. Among them there were the participants (N = 310) recruited in 2019–2021 with an endpoint of 30 October 2021 when these participants were interviewed over phone with relevant questionnaire. Results: Obtained data indicated a percentage of 3–6% of SARS-CoV-2-S1 RBD-specific antibodies detected in participants recruited in 2011–2019. The percentage of SARS-CoV-2-S1 RBD-specific antibodies was increased to 16.5% in 2020 and to 46% in 2021. The vaccination rate of 238 respondents of this cohort was 58% from August 2020 to October 2021. In total, 12% of respondents were hospitalized. The morbidity rate in the subgroup of anti-SARS-CoV-2-S1 RBD-positive respondents was 5.4-fold higher than that in the subgroup of vaccinated respondents. Conclusions: A small percentage of SARS-CoV-2-S1 RBD-specific antibodies detected in 2011–2019 indicated possible spreading of coronaviruses during the pre-pandemic period. Collective immunity in Moscow and the Moscow region was able to reach 69% from August 2020 to October 2021 if this rate is added to the rate of not vaccinated SARS-CoV-2-S1 RBD-positive subjects.

14.
Vaccines ; 10(4), 2022.
Article in English | EMBASE | ID: covidwho-1822474

ABSTRACT

In the present study, antibody and T cell-mediated immune responses elicited by BBIBP-CorV and BNT162b2 vaccines were compared 6 months after the two-dose immunization of healthy individuals. Additionally, antibody and T cell responses after the third dose of BBIBP-CorV or BNT162b2 were compared using a homologous or heterologous vaccination strat-egy. The third dose was consistently administered 6 months after the second dose. Six months following the two-dose vaccination, the cumulative IFNγ-positive T cell response was almost identical in participants immunized with either two doses of BNT162b2 or BBIBP-CorV vaccines;however, significant differences were revealed regarding humoral immunity: the two-dose BNT162b2 vaccine maintained a significantly higher antireceptor-binding domain (RBD) IgG, anti-spike (S1/S2) IgG, and IgA antibody levels. The BNT162b2 + BNT162b2 + BBIBP-CorV vaccine series elicited significantly lower anti-RBD IgG and anti-S1/S2 IgG levels than three doses of BNT162b2, while the anti-S IgA level was equally negligible in both groups. Importantly, the cumulative IFNγ-positive T cell response was highly similar in both groups. Surprisingly, the BBIBP-CorV + BBIBP-CorV + BNT162b2 vaccination series provided a much higher cumulative IFNγ-positive T cell response than that elicited by three doses of BNT162b2;moreover, the levels of anti-RBD IgG and anti-S IgA were almost identical. Only the mean anti-S1/S2 IgG levels were higher after receiving three mRNA vaccines. Based on these data, we can conclude that adminis-tering a third dose of BNT162b2 after two doses of BBIBP-CorV is an effective strategy to significantly enhance both humoral and T cell-mediated immune response, and its effectiveness is com-parable to that of three BNT162b2 vaccines.

15.
Vaccines ; 10(4), 2022.
Article in English | EMBASE | ID: covidwho-1822473

ABSTRACT

In response to the SARS-CoV-2 Delta variant, which partially escaped the vaccine-induced immunity provided by two doses of vaccination with CoronaVac (Sinovac), the National Vaccine Committee recommended the heterologous CoronaVac-ChAdOx1 (Oxford–AstraZeneca), a prime– boost vaccine regimen. This pilot study aimed to describe the immunogenicity and adverse events of the heterologous CoronaVac-ChAdOx1 regimen, in comparison with homologous CoronaVac, and homologous ChAdOx1. Between May and August 2021, we recruited a total of 354 participants from four vaccination groups: the CoronaVac-ChAdOx1 vaccinee (n = 155), the homologous CoronaVac vaccinee (n = 32), the homologous ChAdOx1 vaccinee (n = 47), and control group of COVID-19 patients (n = 120). Immunogenicity was evaluated by measuring the level of IgG antibodies against the receptor-binding domain (anti-SRBD) of the SARS-CoV-2 spike protein S1 subunit and the level of neutralizing antibodies (NAbs) against variants of concern (VOCs) using the plaque reduction neutralization test (PRNT) and pseudovirus neutralization test (pVNT). The safety profile was recorded by interviewing at the 1-month visit after vaccination. The anti-SRBD level after the second booster dose of the CoronaVac-ChAdOx1 group at 2 weeks was higher than 4 weeks. At 4 weeks after the second booster dose, the anti-SRBD level in the CoronaVac-ChAdOx1 group was significantly higher than ei-ther homologous CoronaVac, the homologous ChAdOx1 group, and Control group (p < 0.001). In the CoronaVac-ChAdOx1 group, the PRNT50 level against the wild-type (434.5 BAU/mL) was the high-est;followed by Alpha variant (80.4), Delta variant (67.4), and Beta variant (19.8). The PVNT50 level was also found to be at its highest against the wild-type (432.1);followed by Delta variants (178.3), Alpha variants (163.9), and Beta variant (42.2), respectively. The AEs in the CoronaVac-ChAdOx1 group were well tolerated and generally unremarkable. The CoronaVac-ChAdOx1 heterologous regimen induced higher immunogenicity and a tolerable safety profile. In a situation when only CoronaVac-ChAdOx1 vaccines are available, they should be considered for use in responding to the Delta variant.

16.
Vaccines ; 10(4), 2022.
Article in English | EMBASE | ID: covidwho-1822471

ABSTRACT

Severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2), the etiological agent of COVID-19, has caused over 460 million cases of infection and over 6 million deaths world-wide. The pandemic has called for science, technology, and innovation to provide solutions and, due to an incredible scientific and financial global effort, several prophylactic and therapeutic apparatuses such as monoclonal antibodies and vaccines were developed in less than one year to address this emergency. After SARS-CoV-2 infection, serum neutralizing antibodies are produced by B cells and studies on virus-neutralizing antibodies’ kinetics are pivotal. The process of protective immunity and the duration of this kind of protection against COVID-19 remain to be clarified. We tested 136 sera from 3 groups of individuals, some of them providing multiple sequential sera (1—healthy, no previous CoV2-infected, vaccinated;2—healthy, previous CoV2 infected, vaccinated;3—healed, previous CoV2-infected, not vaccinated) to assess the kinetics of antibodies (Abs) neutralizing activity. We found that SARS-CoV-2 infection elicits moderate neutralizing antibody activity in most individuals;neither age nor gender appear to have any influence on Abs responses. The BNT162b2 vaccine, when administered in two doses, induces high antibodies titre endowed with potent neutralizing activity against bare SARS-CoV-2 in in vitro neutralizing assay. The residual neutralization capability and the kinetic of waning immunity were also evaluated over 9 months after the second dose in a reference group of subjects. Neutralization titre showed a decline in all subjects and the median level of S-protein IgG, over 270 days after the second vaccination dose, was below 10 AU/mLin 53% of serum tested.

17.
Vaccines ; 10(4), 2022.
Article in English | EMBASE | ID: covidwho-1822466

ABSTRACT

The COVID-19 pandemic continues to be a worldwide health issue. Among hemodialysis (HD) patients, two-dose immunization schemes with mRNA vaccines have contributed to preventing severe COVID-19 cases;however, some have not produced a sufficient humoral response, and most have developed a rapid decline in antibody levels over the months following vaccination. This observational, prospective, multi-center study evaluated the humoral response in terms of presence and levels of IgG antibodies to the receptor-binding domain of the S1 spike antigen of SARS-CoV-2 (anti-S1-RBD IgG) to the third dose of SARS-CoV-2 mRNA vaccines, either the mRNA-1273 (Moderna) or BNT162b2 (Pfizer), in 153 patients from three dialysis units affiliated to Hospital Clínic of Barcelona (Spain). Most hemodialysis patients responded intensely to this third vaccine dose, achieving the seroconversion in three out of four non-or weak responders to two doses. Moreover, 96.1% maintained the upper limit or generated higher titers than after the second. BNT162b2 vaccine, active cancer, and immunosuppressive treatment were related to a worse humoral response. Every hemodialysis patient should be administered a third vaccine dose six months after receiving the second one. Despite the lack of data, immunosuppressed patients and those with active cancer may benefit from more frequent vaccine boosters.

18.
Vaccines ; 10(4), 2022.
Article in English | EMBASE | ID: covidwho-1822461

ABSTRACT

This was a retrospective cohort study, which aimed to investigate the factors associated with hesitancy to receive a third dose of a coronavirus disease 2019 (COVID-19) vaccine. A paper-based questionnaire survey was administered to all participants. This study included participants who provided answers in the questionnaire about whether they had an intent to receive a third dose of a vaccine. Data on sex, age, area of residence, adverse reactions after the second vaccination, whether the third vaccination was desired, and reasons to accept or hesitate over the booster vaccination were retrieved. Among the 2439 participants, with a mean (±SD) age of 52.6 ± 18.9 years, and a median IgG-S antibody titer of 324.9 (AU/mL), 97.9% of participants indicated their intent to accept a third vaccination dose. The logistic regression revealed that participants of a younger age (OR = 0.98;95% CI: 0.96–1.00) and with a higher antibody level (OR = 2.52;95% CI: 1.27–4.99) were positively associated with hesitancy over the third vaccine. The efficacy of the COVID-19 vaccine and concerns about adverse reactions had a significant impact on behavior regarding the third vaccination. A rapid increase in the booster dose rate is needed to control the pandemic, and specific approaches should be taken with these groups that are likely to hesitate over the third vaccine, subsequently increasing booster contact rate.

19.
Vaccines ; 10(4), 2022.
Article in English | EMBASE | ID: covidwho-1822459

ABSTRACT

Obesity is a significant factor for increased morbidity and mortality upon infection with SARS-CoV-2. Because of the higher potential for negative outcomes following infection of individuals with obesity, the impact of body mass index (BMI) on vaccine immunogenicity and efficacy is an important public health concern. Few studies have measured the magnitude and durability of the vaccine-specific response in relation to BMI. We measured the receptor binding domain (RBD)-specific serum IgG and surrogate neutralizing titers in a cohort of 126 vaccinated individuals with no clinical history or serological evidence of previous SARS-CoV-2 infection 50 and 200 days following vaccination. BMI had no significant impact on RBD-specific IgG titers and surrogate neutralizing titers 50 days following immunization, and leptin levels had no correlation with the response to immunization. Two hundred days following immunization, antibody titers in all groups had declined by approximately 90%. The responses were also similar between male and female participants and did not significantly vary across age groups. These results indicate that the magnitude and durability of the antibody response to mRNA-based vaccines are unaffected by BMI in this cohort.

20.
Vaccines ; 10(4), 2022.
Article in English | EMBASE | ID: covidwho-1822458

ABSTRACT

The presence of neutralizing antibodies (NAbs) against SARS-CoV-2 represent a surrogate marker of immunologic protection in populations at high risk of infection such as healthcare workers caring for hospitalized patients with COVID-19. As recommended by CDC and the European CDC, the use of rapid diagnostic tests during population-based evaluations offers an opportunity to identify individuals with serologic evidence of natural infection or who have undergone vaccination. We carried out a cross-sectional study to assess the presence of neutralizing antibodies against SARS-CoV-2 among medical providers at an intensive care unit of a large referral hospital in Alicante, Spain. In addition, we tested for the presence of neutralizing antibodies compared to serum of uninfected individuals from a Biobank. We were also interested in evaluating the use of a rapid lateral flow immunochromatography (LFIC) test against a surrogate ELISA viral neutralization test (sVNT). This rapid test demonstrated a specificity of 1.000 95% CI (0.91–1.00) and the sensitivity of 0.987 95% CI (0.93–1.00). The negative predictive value was 95%. After six months, this rapid test demonstrated that those immunized with two doses of BioNTech/Pfizer vaccine, maintained optimal levels of neutralizing antibodies. We concluded that all Health Care Workers develop NAbs and the use of this rapid immunochromatographic test represents a potential tool to be used in population-based studies to detect serological antibody responses to vaccination. Vaccination policies could benefit from this tool to assess additional doses of vaccine or boosters among high-risk populations.

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