Background/Objectives: COVID-19, caused by the SARS-CoV-2 virus, can lead to widespread neurological and cognitive complications, even in the absence of significant structural brain abnormalities. Understanding the evolving health concerns in the context of viral infections is critical to service member readiness, fitness, and mission completion. The potential neuroprotective effects of SARS-CoV-2 vaccination remain underexplored. Methods: Using a cross-sectional, non-human primate model (female cynomolgus macaques), we employed magnetoencephalography (MEG) to assess resting-state brain activity following vaccination with escalating doses of a novel psoralen-inactivated SARS-CoV-2 vaccine (PsIV) or a combination of PsIV and a DNA vaccine (prime boost), and subsequent challenge with the Delta variant (SARS-CoV-2 B.1.617.2). MEG scans were acquired 41 days after inoculation. Source series were constructed for 42 regions of interest for each subject, and band power was computed. Results: Band power demonstrated substantial preservation of neural activity across multiple brain regions in vaccinated subjects compared to unvaccinated controls following viral challenge. Significantly lower power was observed across the brain at all bandwidths in the unvaccinated group relative to the prime boost group. As PsIV concentration increased, spectral power increased, with the prime boost group having the greatest power. Conclusions: This approach not only underscores the role of vaccination in mitigating neuropathology but also highlights the capability of MEG to detect subtle yet significant changes in brain function that may be overlooked by other imaging modalities. These findings advance our understanding of vaccine-induced neuroprotection and establish MEG as a powerful tool for monitoring brain function in the context of viral infections.
COVID-19, caused by the SARS-CoV-2 virus, can lead to widespread neurological complications, including cognitive deficits and neurodegenerative symptoms, even in the absence of significant structural brain abnormalities. The potential neuroprotective effects of SARS-CoV-2 vaccination remain underexplored. Here, we demonstrate the neuroprotective effects of a psoralen-inactivated SARS-CoV-2 vaccine in a non-human primate model using resting-state magnetoencephalography (MEG), a non-invasive neurophysiological recording technique with sub-millisecond temporal and submillimeter spatial resolution. MEG scans demonstrated substantial preservation of neural activity across multiple brain regions in vaccinated subjects compared to unvaccinated controls following viral challenge. This approach not only underscores the role of vaccination in mitigating severe neurological outcomes but also highlights the capability of MEG to detect subtle yet significant changes in brain function that may be overlooked by other imaging modalities. These findings advance our understanding of vaccine-induced neuroprotection and establish MEG as a powerful tool for monitoring brain function in the context of viral infections.
BACKGROUND:Influenza is a major cause of morbidity and mortality worldwide. The Pragmatic Assessment of Influenza Vaccine Effectiveness (VE) in the Department of Defense (PAIVED) study compared the relative VE (rVE) of 2 licensed influenza vaccines (cell culture-based inactivated influenza vaccine [ccIIV] and recombinant influenza vaccine [RIV]) to egg-based inactivated influenza vaccine (eIIV). METHODS:Between 2018 and 2021, PAIVED randomized (1:1:1) eligible Military Health System beneficiaries to receive eIIV, ccIIV, or RIV during an influenza season. Participants received weekly surveys querying influenza-like illness (ILI); those reporting ILI completed an online symptom diary, were interviewed by research staff, and underwent nasal swab collection. Laboratory-confirmed influenza was the primary outcome. Immunogenicity assessment was conducted in a subset of participants. RESULTS:Among 15 432 participants, influenza was identified in 87/5130 (1.7%) ccIIV recipients, 79/5154 (1.5%) RIV recipients, and 69/5148 (1.3%) eIIV recipients during their season of enrollment. rVE of ccIIV compared to eIIV was -27% (95% confidence interval [CI], -73%, 8%), and rVE of RIV compared to eIIV was -14% (95% CI -58%, 17%). RIV (N = 375) recipients were more likely to seroconvert (4-fold increase) than those who received eIIV (N = 355) (A/H1N1: 49.1% vs 29.0%; A/H3N2: 71.2% vs 30.4%; B/Victoria 24.5% vs 13.8%; B/Yamagata 17.1% vs 5.4%; P < .001 for all). ccIIV (N = 357) recipients were more likely to seroconvert only against A/H3N2 compared with eIIV recipients (44.0% vs 30.4%) (P < .001). CONCLUSIONS:Significant differences in VE were not detected comparing egg-based to non-egg-based influenza vaccines, although immunogenicity differences were observed; low influenza case numbers impacted VE estimate precision. TRIAL REGISTRATION:ClinicalTrials.gov NCT03734237.
We performed epidemiological, genetic, and antigenic characterization of an influenza A/H3N2 outbreak in a congregate setting of young adults with high vaccination rates. We noted substantial duty-days lost, rapid spread, and vaccine antigenic divergence. The risk of influenza in healthy vaccinated adults underscores the need to develop universal influenza vaccines.
Vaccine immunogenicity is affected by a variety of factors. Melatonin has been reported to affect immune responses to vaccines and infection. This was a randomized open-label trial - in which adults scheduled to receive the influenza vaccine were randomized to 5 mg melatonin or control to evaluate the effect of post-vaccination melatonin on humoral (hemagglutination-inhibition assays, HAI) and cellular (FluoroSpot) vaccine-specific cytokine responses 14-21 days post-vaccination. A total of 108 participants (melatonin treatment group: 53; control group: 55) completed the study. The groups were similar in baseline characteristics, including sleep as measured by the Pittsburgh Sleep Quality Index. Seroconversion rates or geometric mean fold rises (GMFR) in HAI titers did not vary by treatment group. There were also no statistically significant differences between pre- and post-vaccination levels of interferon gamma (IFN-gamma) or granzyme B (GzB) by treatment; however, there was a significantly higher fold rise in the double secretor (IFN-gamma + GzB) peripheral blood mononuclear cells for influenza vaccine in subjects taking daily melatonin (GMFR 1.7; 95% CI 1.3, 2.3) compared to those who did not (GMFR 0.9; 95% CI 0.7, 1.1) (p < .001). Daily melatonin for 14 days post-influenza vaccination significantly increased the cellular co-expression of IFN-gamma + GzB; however, there were no other differences in the cellular or humoral responses. Future studies of the potential utility of melatonin for enhancing vaccine response with larger sample sizes may help elucidate candidate mechanisms for these limited effects, including any interactions with the circadian system.
COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has significantly impacted public health and the economy worldwide. Most of the currently licensed COVID-19 vaccines act by inhibiting the receptor-binding function of the SARS-CoV-2 spike protein. The constant emergence of SARS-CoV-2 variants resulting from mutations in the receptor-binding domain (RBD) leads to vaccine immune evasion and underscores the importance of broadly acting COVID-19 vaccines. Inactivated whole virus vaccines can elicit broader immune responses to multiple epitopes of several antigens and help overcome such immune evasions. We prepared a psoralen-inactivated SARS-CoV-2 vaccine (SARS-CoV-2 PsIV) and evaluated its immunogenicity and efficacy in nonhuman primates (NHPs) when administered with the Advax-CpG adjuvant. We also evaluated the SARS-CoV-2 PsIV as a booster shot in animals vaccinated with a DNA vaccine that can express the full-length spike protein. The Advax-CpG-adjuvanted SARS-CoV-2 PsIV elicited a dose-dependent neutralizing antibody response in the NHPs, as measured using a serum microneutralization assay against the SARS-CoV-2 Washington strain and the Delta variant. The animals vaccinated with the DNA vaccine followed by a boosting dose of the SARS-CoV-2 PsIV exhibited the highest neutralizing antibody responses and were able to quickly clear infection after an intranasal challenge with the SARS-CoV-2 Delta variant. Overall, the data show that the Advax-CpG-adjuvanted SARS-CoV-2 PsIV, either by itself or as a booster shot following nucleic acid (NA) vaccines, has the potential to protect against emerging variants.
Traditional blood sampling by venipuncture is cumbersome and relatively expensive. Dried blood spot (DBS) sampling is desirable because of its ease of sample collection, transportation and storage. It has been used in clinical diagnosis but not been thoroughly studied for the potential use to assess the immune status of individuals following natural infection or preventive vaccination. The goal of this study was to compare DBS to traditional blood samplings in detection of antibodies in individuals vaccinated against measles, hepatitis A, tetanus, influenza and varicella zoster. Enzyme linked immunosorbent assay (ELISA) was used to test DBS eluates and serum samples for antibodies against measles, varicella, tetanus and hepatitis A. Sensitivities, specificities, and correlation coefficients were evaluated to compare optical density (OD) values of paired serum and DBS samples. The long-term stability of DBS samples at different temperatures was assessed using simulated immune measles blood. DBS OD was highly correlated with serum OD for antibodies to measles (r = 0.93), varicella (r = 0.82), and tetanus (r = 0.91). Sensitivities of DBS OD ranged from 86-99% and specificities ranged from 96-100% using cut-offs established by each assay. By contrast, the hepatitis A data showed a low sensitivity (31%) and weak correlation (r = 0.14) between DBS and serum samples. Antibody titers in serum samples for anti-influenza A (H1N1 and H3N1) failed to correlate in DBS eluates in HAI and MN assays. DBS samples were stable for 4 weeks when stored at room temperature and for 6 months at 4°C. DBS sampling was sensitive, specific, and highly correlated with traditional venipuncture sampling in detection of antibodies against measles, tetanus and varicella zoster, but not hepatitis A and influenza. Thus, the success of using DBS sampling to assess the antibody levels in immunized individuals may be dependent on the pathogens and the development of the assay used.
Background. The relationship between postvaccination symptoms and strength of antibody responses is unclear. The goal of this study was to determine whether adverse effects caused by vaccination with the Pfizer/BioNTech BNT162b2 vaccine are associated with the magnitude of vaccine-induced antibody levels. Methods. We conducted a single-center, observational cohort study consisting of generally healthy adult participants that were not severely immunocompromised, had no history of coronavirus disease 2019, and were seronegative for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein before vaccination. Severity of vaccine-associated symptoms was obtained through participant-completed questionnaires. Testing for immunoglobulin G antibodies against SARS-CoV-2 spike protein and receptor-binding domain was conducted using microsphere-based multiplex immunoassays performed on serum samples collected at monthly visits. Neutralizing antibody titers were determined by microneutralization assays. Results. Two hundred six participants were evaluated (69.4% female, median age 41.5 years old). We found no correlation between vaccine-associated symptom severity scores and vaccine-induced antibody titers 1 month after vaccination. We also observed that (1) postvaccination symptoms were inversely correlated with age and weight and more common in women, (2) systemic symptoms were more frequent after the second vaccination, (3) high symptom scores after first vaccination were predictive of high symptom scores after second vaccination, and (4) older age was associated with lower titers. Conclusions. Lack of postvaccination symptoms after receipt of the BNT162b2 vaccine does not equate to lack of vaccine-induced antibodies 1 month after vaccination.
The development of a safe and effective vaccine to protect against COVID-19 is a global priority due to the current high SARS-CoV-2 infection rate. Currently, there are over 160 SARS-CoV-2 vaccine candidates at the clinical or pre-clinical stages of development. Of these, there are only three whole-virus vaccine candidates produced using β-propiolactone or formalin inactivation. Here, we prepared a whole-virus SARS-CoV-2 vaccine (SARS-CoV-2 PsIV) using a novel psoralen inactivation method and evaluated its immunogenicity in mice using two different adjuvants, alum and Advax-2. We compared the immunogenicity of SARS-CoV-2 PsIV against SARS-CoV-2 DNA vaccines expressing either full-length or truncated spike proteins. We also compared the psoralen-inactivated vaccine against a DNA prime, psoralen-inactivated vaccine boost regimen. After two doses, the psoralen-inactivated vaccine, when administered with alum or Advax-2 adjuvants, generated a dose-dependent neutralizing antibody responses in mice. Overall, the pattern of cytokine ELISPOT responses to antigen-stimulation observed in this study indicates that SARS-CoV-2 PsIV with the alum adjuvant promotes a Th2-type response, while SARS-CoV-2 PsIV with the Advax-2 adjuvant promotes a Th1-type response.
Delayed pain is a common vaccine adverse event after inactivated influenza vaccine (IIV) receipt. Nonsteroidal anti-inflammatory drugs (NSAIDs) are a typical intervention, and within military lore, pushups are reputed to be an effective preventive measure. We studied the effect of prescription strength ibuprofen and exercise in the form of pushups on delayed pain and local inflammation symptoms after receipt of IIV and their impact on immunogenicity in military Service Members (SMs).
Dengue fever, caused by dengue viruses (DENV 1-4) is a leading cause of illness and death in the tropics and subtropics. Therefore, an effective vaccine is urgently needed. Currently, the only available licensed dengue vaccine is a chimeric live attenuated vaccine that shows varying efficacy depending on serotype, age and baseline DENV serostatus. Accordingly, a dengue vaccine that is effective in seronegative adults, children of all ages and in immunocompromised individuals is still needed. We are currently researching the use of psoralen to develop an inactivated tetravalent dengue vaccine. Unlike traditional formalin inactivation, psoralen inactivates pathogens at the nucleic acid level, potentially preserving envelope protein epitopes important for protective anti-dengue immune responses. We prepared highly purified monovalent vaccine lots of formalin- and psoralen-inactivated DENV 1-4, using Capto DeVirS and Capto Core 700 resin based column chromatography. Tetravalent psoralen-inactivated vaccines (PsIV) and formalin-inactivated vaccines (FIV) were prepared by combining the four monovalent vaccines. Mice were immunized with either a low or high dose of PsIV or FIV to evaluate the immunogenicity of monovalent as well as tetravalent formulations of each inactivation method. In general, the monovalent and tetravalent PsIVs elicited equivalent or higher titers of neutralizing antibodies to DENV than the FIV dengue vaccines and this response was dose dependent. The immunogenicity of tetravalent dengue PsIVs and FIVs were also evaluated in nonhuman primates (NHPs). Consistent with what was observed in mice, significantly higher neutralizing antibody titers for each dengue serotype were observed in the NHPs vaccinated with the tetravalent dengue PsIV compared to those vaccinated with the tetravalent dengue FIV, indicative of the importance of envelope protein epitope preservation during psoralen inactivation of DENV. (C) 2020 The Authors. Published by Elsevier Ltd.
Abstract Introduction and background A tetravalent DNA vaccine for Dengue virus is under development but has not yet achieved optimal immunogenicity. Salivary glands vaccination has been reported efficacious in rodents and dogs. We report on a pilot study testing the salivary gland as a platform for a Dengue DNA vaccine in a non-human primate model. Materials and methods Four cynomolgus macaques were used in this study. Each macaque was pre-medicated with atropine and sedated with ketamine. Stensen’s duct papilla was cannulated with a P10 polyethylene tube, linked to a 500ul syringe. On the first two infusions, all macaques were infused with 300ul of TVDV mixed with 2 mg of zinc. For the 3rd infusion, to increase transfection into salivary tissue, two animals received 100uL TVDV mixed with 400uL polyethylenimine 1μg/ml (PEI) and the other two animals received 500uL TVDV with zinc. Antibody titers were assessed 4 weeks following the second and third infusion. Results and conclusions SGRI through Stensen’s duct is a well-tolerated, simple and easy to reproduce procedure. TVDV infused into macaques salivary glands elicited a significantly weaker antibody response than with different delivery methods.
Objective: To describe an outbreak of influenza A in an oncology unit, highlighting infection control methods implemented, and examining reasons health care workers (HCWs) present to work with influenza-like illness (ILI). Methods: Confirmed cases were defined by the presence of ILI and a positive nasopharyngeal polymerase chain reaction swab for influenza A H3. Probable cases were defined as exposed HCWs with ILI who were unavailable for polymerase chain reaction testing. Infection prevention measures included closing the ward for new admissions, oseltamivir prophylaxis for all exposed groups, and dismissal from work of HCWs with ILI until resolution of symptoms. An anonymous survey of the cases in our HCWs was conducted to better elucidate reasons behind presenteeism. Results: Over the course of 8 days (November 16, 2017, to November 22, 2017), influenza was diagnosed in 7 of 10 inpatients on the oncology ward, 16 HCWs (14 confirmed, 2 probable), and 2 visitors. The suspected index case was an HCW. Of the surveyed HCWs, 64% presented to work despite feeling ill (ie, presenteeism). The most common reason was "sense of duty as a health care worker." Conclusions: This nosocomial outbreak of influenza highlights the challenges of protecting inpatients from viral respiratory tract infections. HCWs and patient visitors with ILI should avoid work or visiting until resolution of peak respiratory symptoms and adhere to strict respiratory etiquette. (C) 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Background: In outbreak settings, mass vaccination strategies could maximize health protection of military personnel. Self-administration of live attenuated influenza vaccine (LAIV) may be a means to vaccinate large numbers of people and achieve deployment readiness while sparing the use of human resources.Methods: A phase IV, open-label, randomized controlled trial evaluating the immunogenicity and acceptance of self-administered (SA) LAIV was conducted from 2012 to 2014. SA subjects were randomized to either individual self-administration or self-administration in a group setting. Control randomized subjects received healthcare worker-administered (HCWA) LAIV. Anti-hemagglutinin (HAI) antibody concentrations were measured pre- and post-vaccination. The primary endpoint was immunogenicity non-inferiority between SA and HCWA groups. Subjects were surveyed on preferred administration method.Results: A total of 1077 subjects consented and were randomized (529 SA, 548 HCWA). Subject characteristics were very similar between groups, though SA subjects were younger, more likely to be white and on active duty. The per-protocol analysis included 1024 subjects (501 SA, 523 HCWA). Post-vaccination geometric mean titers by vaccine strain and by study group (HCWA vs. SA) were: A/H1N1 (45.8 vs. 48.7, respectively; p = 0.43), A/H3N2 (45.5 vs. 46.4; p=0.80), B/Yamagata (17.2 vs. 17.8; p=0.55). Seroresponses to A components were high (similar to 67%), while seroresponses to B components were lower (similar to 25%). Seroresponse did not differ by administration method. Baseline preference for administration method was similar between groups, with the majority in each group expressing no preference. At follow-up, the majority (64%) of SA subjects preferred SA vaccine.Conclusions: LAIV immunogenicity was similar for HCWA and SA vaccines. SA was well-tolerated and preferred to HCWA among those who performed SA. (C) 2015 Elsevier Ltd. All rights reserved.
Atomic layer deposition (ALD) provides a promising approach for deposition of ultrathin low-defect-density tunnel barriers, and it has been implemented in a high-vacuum magnetron sputtering system for in situ deposition of ALD-Al2O3 tunnel barriers in superconductor-insulator-superconductor Josephson junctions. A smooth ALD-Al2O3 barrier layer was grown on an Al-wetted Nb bottom electrode and was followed with a top Nb electrode growth using sputtering. Preliminary low temperature measurements of current-voltage characteristics of the Josephson junctions made from these trilayers confirmed the integrity of the ALD-Al2O3 barrier layer. However, the IcRN product of the junctions is much smaller than the value expected from the Ambegaokar-Baratoff formula suggesting a significant pair-breaking mechanism at the interfaces.
Atomic layer deposition (ALD) provides a promising approach for deposition of ultrathin low-defect-density tunnel barriers, and it has been implemented in a high-vacuum magnetron sputtering system for in situ deposition of ALD-Al2O3 tunnel barriers in superconductor-insulator-superconductor Josephson junctions. A smooth ALD-Al2O3 barrier layer was grown on an Al-wetted Nb bottom electrode and was followed with a top Nb electrode growth using sputtering. Preliminary low temperature measurements of current-voltage characteristics of the Josephson junctions made from these trilayers confirmed the integrity of the ALD-Al2O3 barrier layer. However, the IcRN product of the junctions is much smaller than the value expected from the Ambegaokar-Baratoff formula suggesting a significant pair-breaking mechanism at the interfaces.
A prototype dengue-1 DNA vaccine was shown to be safe and immunogenic in a previous Phase 1 clinical trial. Anti-dengue-1 neutralizing antibody responses were detectable only in the group of volunteers receiving the high dose of nonadjuvanted vaccine and the antibody titers were low. Vaxfectin(®), a lipid-based adjuvant, enhances the immunogenicity of DNA vaccines. We conducted a nonhuman primate study to evaluate the effect of Vaxfectin(®) on the immunogenicity of a tetravalent dengue DNA vaccine. Animals were immunized on days 0, 28 and 84, with each immunization consisting of 3mg of Vaxfectin(®)-adjuvanted tetravalent dengue DNA vaccine. The use of Vaxfectin(®) resulted in a significant increase in anti-dengue neutralizing antibody responses against dengue-1, -3 and -4. There was little to no effect on T cell responses as measured by interferon gamma ELISPOT assay. Animals immunized with the Vaxfectin(®)-formulated tetravalent DNA vaccine showed significant protection against live dengue-2 virus challenge compared to control animals (0.75 mean days of viremia vs 3.3 days). Animals vaccinated with nonadjuvanted DNA had a mean 2.0 days of viremia. These results support further evaluation of the Vaxfectin(®)-adjuvanted tetravalent dengue DNA vaccine in a Phase 1 clinical trial.