Interim Results of a Phase 1-2a Trial of Ad26.COV2.S Covid-19 Vaccine

The association of COVID-19 vaccination and menstrual health: A period-tracking app-based cohort study

Background

In initial COVID-19 clinical trials, menstrual health was not formally monitored, yet anecdotal reports of menstruation changes surfaced on social media. This study aims to assess the association between COVID-19 vaccines and menstruation using Clue, a period-tracking application.

Study design

A survey assessing demographics, menstrual health, stress levels, and COVID-19 vaccination was sent to Clue users between 12/7/2021 and 2/9/2022. Inclusion criteria were (1) 18 years or older (2) currently menstruating (3) not pregnant or breastfeeding since 1/2020. Menstrual data was collected for each participant. Users with cycle lengths more than 90 days were excluded. Cycle lengths were calculated for the 6-month average pre-vaccination (PRIOR), the cycle during which vaccination was administered (DURING), the cycle following DURING (AFTER1), and the cycle following AFTER1 (AFTER2). For periods, individuals were stratified based on whether vaccination was received during their menstrual period (DURING). Period lengths were additionally calculated for the 6-month average pre-vaccination (PRIOR), the first period following vaccination (AFTER1), and the period following AFTER1 (AFTER2). For unvaccinated participants, an index date (4/1/2022) was used to similarly designate menstrual cycles and periods. For each participant, cycle length changes for DURING, AFTER1, and AFTER2 compared to PRIOR were determined. Student's t-test compared the mean of these changes between vaccinated and unvaccinated groups.

Results

Of 7,559 participants, 6,897 (91 %) were vaccinated. Compared to PRIOR, individuals vaccinated during their menstrual period demonstrated a statistically significant increase in the DURING period length, but not AFTER1 (p = 0.463) and AFTER2 (p = 0.692). No statistically significant changes were observed in period lengths of those vaccinated in between periods or in cycle lengths overall.

Conclusion

A small but statistically significant change in period length was observed only in individuals vaccinated for COVID-19 during their menstrual period. Providers can better counsel menstruating individuals to reduce vaccine misinformation.

Vaccine delivery systems and administration routes: Advanced biotechnological techniques to improve the immunization efficacy

Since the first use of vaccine tell the last COVID-19 pandemic caused by spread of SARS-CoV-2 worldwide, the use of advanced biotechnological techniques has accelerated the development of different types and methods for immunization. The last pandemic showed that the nucleic acid-based vaccine, especially mRNA, has an advantage in terms of development time; however, it showed a very critical drawback namely, the higher costs when compared to other strategies, and its inability to protect against new variants. This showed the need of more improvement to reach a better delivery and efficacy. In this review we will describe different vaccine delivery systems including, the most used viral vector, and also variable strategies for delivering of nucleic acid-based vaccines especially lipid-based nanoparticles formulation, polymersomes, electroporation and also the new powerful tools for the delivery of mRNA, which is based on the use of cell-penetrating peptides (CPPs). Additionally, we will also discuss the main challenges associated with each system. Finlay, the efficacy and safety of the vaccines depends not only on the formulations and delivery systems, but also the dosage and route of administration are also important players, therefore we will see the different routes for the vaccine administration including traditionally routes (intramuscular, Transdermal, subcutaneous), oral inhalation or via nasal mucosa, and will describe the advantages and disadvantage of each administration route.

Safety, reactogenicity, and immunogenicity of Ad26.COV2.S as homologous or heterologous COVID-19 booster vaccination: Results of a randomized, double-blind, phase 2 trial

COVID-19 vaccine boosters may optimize durability of protection against variants of concern (VOCs). In this randomized, double-blind, phase 2 trial, participants received 3 different dose levels of an Ad26.COV2.S booster (5 × 1010 vp [viral particles], 2.5 × 1010 vp, or 1 × 1010 vp) ≥6 months post-primary vaccination with either single-dose Ad26.COV2.S (homologous boost; n = 774) or 2-dose BNT162b2 (heterologous boost; n = 758). Primary endpoints were noninferiority of neutralizing antibody responses at Day 15 post-boost versus Day 29 post-primary vaccination. Secondary endpoints included reactogenicity/safety and neutralizing antibody responses to VOCs. All primary endpoints passed prespecified hierarchical noninferiority criteria by Day 15 post-boost. Geometric mean increases in neutralizing antibody titers against the D614G reference strain ranged from 5.5 to 6.8 at Day 15 for homologous boosting and 12.6 to 22.0 for heterologous boosting. For VOCs, heterologous boosting elicited higher neutralizing antibody responses than homologous boosting. Neutralizing antibody responses were dose-dependent and durable for ≥6 months post-boost. More solicited systemic adverse events occurred following heterologous versus homologous boosting. Trial Registration:ClinicalTrials.gov Identifier: NCT04999111.

COVID-19 vaccine immunogenicity and safety surrounding fourth and subsequent vaccine doses in patients with hematologic malignancies

BACKGROUND

Immune response to COVID-19 vaccine is diminished in patients with hematologic malignancy. There is limited data regarding response to vaccine doses in these patients.

PURPOSE

To quantify the humoral immune response engendered by 4th and subsequent doses of SARS-CoV-2 vaccination as measured by anti-Spike (anti-S) antibody levels, based on dried blood spot (DBS) testing, in patients with hematologic malignancies. Anti-S binds to the spike protein of the SARS-CoV-2 virus and is indicative of vaccine immunogenicity.

METHODS

We conducted a prospective study of hematologic malignancies between August 2021 and January 2023 at 12 sites across Canada. Participants were followed longitudinally and submitted finger-prick DBS cards at set intervals associated with vaccination. Samples were processed via high throughput ELISA assay to detect serum antibodies against nucleocapsid (N) and spike (S) proteins.

RESULTS

We obtained 3071 samples on 790 unique patients. Of these, 372 unique participants with 1840 samples had anti-S results available post-4th, 5th or 6th COVID-19 vaccine dose and were included for analysis. Three hundred thirty-three patients of the 372 participants submitted a DBS sample post 4th dose. Of these, 257 patients (77.2%) had a positive anti-S antibody. A total of 198 patients had paired samples pre- and post-dose 4, of which 59 (29.7%) had a negative anti-S antibody pre-dose 4. Of these, 20 (33.4%) developed positive anti-S antibody post-dose 4. One hundred forty-nine patients submitted a DBS sample post-dose 5. Of these, 135 patients (90.6%) had positive anti-S antibody. A total of 52 had paired samples pre- and post-dose 5. Six (8.7%) had a negative anti-S antibody pre-dose 5, of which two (33.3%) developed positive anti-S antibody post-dose 5. Of these 372 patients, 123 (34%) reported COVID-19 infection and 4 (1%) had a COVID-19 related hospitalization. There were no reported deaths from COVID-19.

CONCLUSIONS

This prospective cohort study showed that humoral immune response improved with subsequent doses of COVID-19 vaccines.

Safety and immunogenicity of Ad26.COV2.S in adults: A randomised, double-blind, placebo-controlled Phase 2a dose-finding study

BACKGROUND

A single dose of Ad26.COV2.S is well-tolerated and effective in preventing moderate-to-severe disease outcomes due to COVID-19. We evaluated the impact of dose level, number of doses, and dose interval on immunogenicity, reactogenicity, and safety of Ad26.COV2.S in adults. Anamnestic responses were also explored.

METHODS

This randomised, double-blind, placebo-controlled, Phase 2a study was conducted in adults aged 18-55 years and ≥ 65 years (NCT04535453). Four dose levels (1.25 × 1010, 2.5 × 1010, 5 × 1010, and 1 × 1011 viral particles [vp], single and 2-dose schedules, and dose intervals of 56 and 84 days, were assessed. Four or 6 months post-primary vaccination, Ad26.COV2.S 1.25 × 1010 vp was given to evaluate anamnestic responses. Humoral and cell-mediated immune responses were measured. Reactogenicity and safety were assessed in all participants.

RESULTS

All Ad26.COV2.S schedules induced humoral responses with evidence of a dose response relationship. A single dose of Ad26.COV2.S (5 × 1010 vp) induced antibody and cellular immune responses that persisted for up to at least 6 months. In the 2-dose regimens, antibody responses were higher than 1-dose regimens at comparable dose levels, and the magnitude of the immune response increased when the interval between doses was increased (84 days vs 56 days). Rapid, marked immune responses were observed in all groups after vaccine antigen exposure indicating immune memory. Durable immune responses were observed in all groups for up to at least 6 months post-antigen exposure. Strong and consistent correlations between neutralising and binding antibodies were observed CD4 + and CD8 + T cell responses were similar after all regimens. Reactogenicity within 7 days post-vaccination tended to be dose-related.

CONCLUSION

The study supports the primary, single dose schedule with Ad26.COV2.S at 5 × 1010 vp and homologous booster vaccination after a 6 month interval. Rapid and marked responses to vaccine antigen exposure indicate induction of immune memory by 1- and 2-dose primary vaccination.

Effect of Prior ChAdOx1 COVID-19 Immunisation on T-Cell Responses to ChAdOx1-HBV

There are varying data concerning the effect of prior anti-vector immunity on the T-cell response induced by immunisation with an identical vectored vaccine containing a heterologous antigen insert. To determine whether prior exposure to ChAdOx1-SARS-CoV2 immunisation (Vaxzevria®) impacts magnitudes of antigen-specific T-cell responses elicited by subsequent administration of the same viral vector (encoding HBV antigens, ChAdOx1-HBV), healthy volunteers that had received Vaxzevria® (n = 15) or the Pfizer or Moderna mRNA COVID-19 vaccine (n = 11) between 10 and 18 weeks prior were recruited to receive a single intramuscular injection of ChAdOx1-HBV. Anti-ChAdOx1-neutralising antibody titers were determined, and vector or insert-specific T-cell responses were measured by a gamma-interferon ELISpot and intracellular cytokine staining (ICS) assay using multiparameter flow cytometry. Participants were followed for three months after the ChAdOx1-HBV injection, which was well-tolerated, and no dropouts occurred. The baseline ChAdOx1 neutralisation titers were higher in the Vaxzevria® cohort (median of 848) than in the mRNA cohort (median of 25). T-cell responses to HBV antigens, measured by ELISpot, were higher on day 28 in the mRNA group (p = 0.013) but were similar between groups on day 84 (p = 0.441). By ICS, these differences persisted at the last time point. There was no clear correlation between the baseline responses to the adenoviral hexon and the subsequent ELISpot responses. As vaccination within 3 months using the same viral vector backbone affected the insert-specific T-cell responses, a greater interval after prior adenoviral immunisation using heterologous antigens may be warranted in settings in which these cells play critical roles.

Cutaneous adverse reactions associated with COVID-19 vaccines: Current evidence and potential immune mechanisms

As the number of vaccinated individuals has increased, there have been increasing reports of cutaneous hypersensitivity reactions. The main COVID-19 vaccines administered include messenger ribonucleic acid vaccines, non-replicating viral vector vaccines, inactivated whole-virus vaccines, and protein-based vaccines. These vaccines contain active components such as polyethylene glycol, polysorbate 80, aluminum, tromethamine, and disodium edetate dihydrate. Recent advances in understanding the coordination of inflammatory responses by specific subsets of lymphocytes have led to a new classification based on immune response patterns. We categorize these responses into four patterns: T helper (Th)1-, Th2-, Th17/22-, and Treg-polarized cutaneous inflammation after stimulation of COVID-19 vaccines. Although the association between COVID-19 vaccination and these cutaneous adverse reactions remains controversial, the occurrence of rare dermatoses and their short intervals suggest a possible relationship. Despite the potential adverse reactions, the administration of COVID-19 vaccines is crucial in the ongoing battle against severe acute respiratory syndrome coronavirus 2.

The Biodistribution of the Spike Protein after Ad26.COV2.S Vaccination Is Unlikely to Play a Role in Vaccine-Induced Immune Thrombotic Thrombocytopenia

Ad26.COV2.S vaccination can lead to vaccine-induced immune thrombotic thrombocytopenia (VITT), a rare but severe adverse effect, characterized by thrombocytopenia and thrombosis. The mechanism of VITT induction is unclear and likely multifactorial, potentially including the activation of platelets and endothelial cells mediated by the vaccine-encoded spike protein (S protein). Here, we investigated the biodistribution of the S protein after Ad26.COV2.S dosing in three animal models and in human serum samples. The S protein was transiently present in draining lymph nodes of rabbits after Ad26.COV2.S dosing. The S protein was detected in the serum in all species from 1 day to 21 days after vaccination with Ad26.COV2.S, but it was not detected in platelets, the endothelium lining the blood vessels, or other organs. The S protein S1 and S2 subunits were detected at different ratios and magnitudes after Ad26.COV2.S or COVID-19 mRNA vaccine immunization. However, the S1/S2 ratio did not depend on the Ad26 platform, but on mutation of the furin cleavage site, suggesting that the S1/S2 ratio is not VITT related. Overall, our data suggest that the S-protein biodistribution and kinetics after Ad26.COV2.S dosing are likely not main contributors to the development of VITT, but other S-protein-specific parameters require further investigation.

SARS-CoV-2 Neutralization Assays Used in Clinical Trials: A Narrative Review

Since the emergence of COVID-19, extensive research efforts have been undertaken to accelerate the development of multiple types of vaccines to combat the pandemic. These include inactivated, recombinant subunit, viral vector, and nucleic acid vaccines. In the development of these diverse vaccines, appropriate methods to assess vaccine immunogenicity are essential in both preclinical and clinical studies. Among the biomarkers used in vaccine evaluation, the neutralizing antibody level serves as a pivotal indicator for assessing vaccine efficacy. Neutralizing antibody detection methods can mainly be classified into three types: the conventional virus neutralization test, pseudovirus neutralization test, and surrogate virus neutralization test. Importantly, standardization of these assays is critical for their application to yield results that are comparable across different laboratories. The development and use of international or regional standards would facilitate assay standardization and facilitate comparisons of the immune responses induced by different vaccines. In this comprehensive review, we discuss the principles, advantages, limitations, and application of different SARS-CoV-2 neutralization assays in vaccine clinical trials. This will provide guidance for the development and evaluation of COVID-19 vaccines.

The Equal Neutralizing Effectiveness of BNT162b2, ChAdOx1 nCoV-19, and Sputnik V Vaccines in the Palestinian Population

Since the beginning of the COVID-19 pandemic, different viral vector-based and mRNA vaccines directed against the SARS-CoV-2 "S" spike glycoprotein have been developed and have shown a good profile in terms of safety and efficacy. Nevertheless, an unbiased comparison of vaccination efficiency, including post-vaccination neutralizing activity, between the different vaccines remains largely unavailable. This study aimed to compare the efficacy of one mRNA (BNT162b2) and two non-replicating adenoviral vector vaccines (ChAdOx1 nCoV-19 and Sputnik V) in a cohort of 1120 vaccinated Palestinian individuals who received vaccines on an availability basis and which displayed a unique diversity of genetic characteristics. We assessed the level of anti-S antibodies and further determined the antibody neutralizing activity in 261 of those individuals vaccinated with BNT162b2a (121), ChAdOx1 (72) or Sputnik V (68). Our results showed no significant difference in the distribution of serum-neutralizing activity or S-antibody serum levels for the three groups of vaccines, proving equivalence in efficacy for the three vaccines under real-life conditions. In addition, none of the eight demographic parameters tested had an influence on vaccination efficacy. Regardless of the vaccine type, the vaccination campaign ultimately played a pivotal role in significantly reducing the morbidity and mortality associated with COVID-19 in Palestine.

A chimeric adenovirus-vectored vaccine based on Beta spike and Delta RBD confers a broad-spectrum neutralization against Omicron-included SARS-CoV-2 variants

Urgent research into innovative severe acute respiratory coronavirus-2 (SARS-CoV-2) vaccines that may successfully prevent various emerging emerged variants, particularly the Omicron variant and its subvariants, is necessary. Here, we designed a chimeric adenovirus-vectored vaccine named Ad5-Beta/Delta. This vaccine was created by incorporating the receptor-binding domain from the Delta variant, which has the L452R and T478K mutations, into the complete spike protein of the Beta variant. Both intramuscular (IM) and intranasal (IN) vaccination with Ad5-Beta/Deta vaccine induced robust broad-spectrum neutralization against Omicron BA.5-included variants. IN immunization with Ad5-Beta/Delta vaccine exhibited superior mucosal immunity, manifested by higher secretory IgA antibodies and more tissue-resident memory T cells (TRM) in respiratory tract. The combination of IM and IN delivery of the Ad5-Beta/Delta vaccine was capable of synergically eliciting stronger systemic and mucosal immune responses. Furthermore, the Ad5-Beta/Delta vaccination demonstrated more effective boosting implications after two dosages of mRNA or subunit recombinant protein vaccine, indicating its capacity for utilization as a booster shot in the heterologous vaccination. These outcomes quantified Ad5-Beta/Delta vaccine as a favorable vaccine can provide protective immunity versus SARS-CoV-2 pre-Omicron variants of concern and BA.5-included Omicron subvariants.

The European Academy of Neurology NeuroCOVID-19 Task Force: A lesson for the future

BACKGROUND

The COVID-19 pandemic has made its mark on world history forever causing millions of deaths, and straining health systems, economies, and societies worldwide. The European Academy of Neurology (EAN) reacted promptly. A special NeuroCOVID-19 Task Force was set up at the beginning of the pandemic to promote knowledge, research, international collaborations, and raise awareness about the prevention and treatment of COVID-19-related neurological issues.

METHODS

Activities carried out during and after the pandemic by the EAN NeuroCOVID-19 Task Force are described. The main aim was to review all these initiatives in detail as an overarching lesson from the past to improve the present and be better prepared in case of future pandemics.

RESULTS

During the pandemic, the Task Force was engaged in several initiatives: the creation of the EAN NEuro-covid ReGistrY (ENERGY); the launch of several surveys (neurological manifestations of COVID-19 infection; the pandemic's impact on patients with chronic neurological diseases; the pandemic's impact of restrictions for clinical practice, curricular training, and health economics); the publication of position papers regarding the management of patients with neurological diseases during the pandemic, and vaccination hesitancy among people with chronic neurological disorders; and the creation of a dedicated "COVID-19 Breaking News" section in EANpages.

CONCLUSIONS

The EAN NeuroCOVID-19 Task Force was immediately engaged in various activities to participate in the fight against COVID-19. The Task Force's concerted strategy may serve as a foundation for upcoming global neurological emergencies.

Improving Influenza Vaccination Coverage in Patients with Cancer: A Position Paper from a Multidisciplinary Expert Group

Patients with cancer can be immunocompromised because of their disease and/or due to anticancer therapy. In this population, severe influenza virus infections are associated with an elevated risk of morbidity and mortality. Influenza vaccination is therefore highly recommended in cancer patients, including those receiving anticancer therapy. However, vaccination coverage remains far below the recommended target for vulnerable subjects. Six specialists in oncology, hematology, immunology, and public health/vaccinology convened with the objective of developing strategies, based on evidence and clinical experience, for improving influenza vaccination coverage in cancer patients. This viewpoint provides an overview of current influenza vaccination recommendations in cancer patients, discusses barriers to vaccination coverage, and presents strategies for overcoming said barriers. New immunization issues raised by the COVID-19 pandemic are also addressed. Future directions include improving public education on influenza vaccination, providing the media with accurate information, improving knowledge among healthcare professionals, improving access to vaccines for cancer patients, co-administration of the influenza and COVID-19 vaccines, increased collaboration between oncologists and other health professionals, increased accessibility of digital vaccination registries to specialists, shared information platforms, and promoting immunization campaigns by healthcare systems with the support of scientific societies.

Peak transgene expression after intramuscular immunization of mice with adenovirus 26-based vector vaccines correlates with transgene-specific adaptive immune responses

Non-replicating adenovirus-based vectors have been broadly used for the development of prophylactic vaccines in humans and are licensed for COVID-19 and Ebola virus disease prevention. Adenovirus-based vectored vaccines encode for one or more disease specific transgenes with the aim to induce protective immunity against the target disease. The magnitude and duration of transgene expression of adenovirus 5- based vectors (human type C) in the host are key factors influencing antigen presentation and adaptive immune responses. Here we characterize the magnitude, duration, and organ biodistribution of transgene expression after single intramuscular administration of adenovirus 26-based vector vaccines in mice and evaluate the differences with adenovirus 5-based vector vaccine to understand if this is universally applicable across serotypes. We demonstrate a correlation between peak transgene expression early after adenovirus 26-based vaccination and transgene-specific cellular and humoral immune responses for a model antigen and SARS-CoV-2 spike protein, independent of innate immune activation. Notably, the memory immune response was similar in mice immunized with adenovirus 26-based vaccine and adenovirus 5-based vaccine, despite the latter inducing a higher peak of transgene expression early after immunization and a longer duration of transgene expression. Together these results provide further insights into the mode of action of adenovirus 26-based vector vaccines.

Safety and immunogenicity of booster vaccination and fractional dosing with Ad26.COV2.S or BNT162b2 in Ad26.COV2.S-vaccinated participants

We report the safety and immunogenicity of fractional and full dose Ad26.COV2.S and BNT162b2 in an open label phase 2 trial of participants previously vaccinated with a single dose of Ad26.COV2.S, with 91.4% showing evidence of previous SARS-CoV-2 infection. A total of 286 adults (with or without HIV) were enrolled >4 months after an Ad26.COV2.S prime and randomized 1:1:1:1 to receive either a full or half-dose booster of Ad26.COV2.S or BNT162b2 vaccine. B cell responses (binding, neutralization and antibody dependent cellular cytotoxicity-ADCC), and spike-specific T-cell responses were evaluated at baseline, 2, 12 and 24 weeks post-boost. Antibody and T-cell immunity targeting the Ad26 vector was also evaluated. No vaccine-associated serious adverse events were recorded. The full- and half-dose BNT162b2 boosted anti-SARS-CoV-2 binding antibody levels (3.9- and 4.5-fold, respectively) and neutralizing antibody levels (4.4- and 10-fold). Binding and neutralizing antibodies following half-dose Ad26.COV2.S were not significantly boosted. Full-dose Ad26.COV2.S did not boost binding antibodies but slightly enhanced neutralizing antibodies (2.1-fold). ADCC was marginally increased only after a full-dose BNT162b2. T-cell responses followed a similar pattern to neutralizing antibodies. Six months post-boost, antibody and T-cell responses had waned to baseline levels. While we detected strong anti-vector immunity, there was no correlation between anti-vector immunity in Ad26.COV2.S recipients and spike-specific neutralizing antibody or T-cell responses post-Ad26.COV2.S boosting. Overall, in the context of hybrid immunity, boosting with heterologous full- or half-dose BNT162b2 mRNA vaccine demonstrated superior immunogenicity 2 weeks post-vaccination compared to homologous Ad26.COV2.S, though rapid waning occurred by 12 weeks post-boost. Trial Registration: The study has been registered to the South African National Clinical Trial Registry (SANCTR): DOH-27-012022-7841. The approval letter from SANCTR has been provided in the up-loaded documents.

Factors affecting different COVID-19 outcomes in patients with systemic lupus erythematosus during the second pandemic wave of COVID-19 in China

OBJECTIVE

To investigate characteristics associated with different COVID-19 outcomes of people with systemic lupus erythematosus (SLE) and COVID-19 during the second pandemic wave of COVID-19 in China.

METHODS

In this retrospective study, people with SLE and COVID-19 who visited the First Affiliated Hospital of Nanchang University from December 2022 and February 2023 were subjected to this study. The three possible outcomes were listed in order of ordinal severity: (1) not hospitalized, (2) hospitalized but not receiving oxygenation, and (3) hospitalized with any ventilation or oxygenation. A multivariable ordinal logistic regression model was built to examine the association between COVID-19 severity and demographic traits, medications, comorbidities, and disease activity. Furthermore, among the 301 SLE patients included in our study, only two patients experienced mortality. In order to maintain statistical rigor, we have included these two deceased patients in the outcome measure of hospitalized with any ventilation or oxygenation.

RESULTS

A total of 301 patients with SLE were enrolled in this study. The multivariate ordinal logistic regression analyses indicated that high SLE disease activity (vs remission; OR 39.04, 95% CI 3.08 to 494.44, p = .005) was associated with more severe outcomes. Three doses of COVID-19 vaccination (OR 0.19, 95% CI 0.07 to 0.51, p = .001), glucocorticoids dose (1-5 mg/day 0.14, 0.03 to 0.73, p = .020, and 6-9 mg/day 0.12, 0.02 to 0.61, p = .010), and more intensive immunosuppression drugs (0.34, 0.12 to 0.97, p = .044) were associated with better outcomes. In age-adjusted and sex-adjusted models, telitacicept (6.66, 1.35 to 32.86, p = .020) and rituximab (7.81, 1.87 to 32.66, p = .005) were associated with more severe outcomes. Hydroxychloroquine (0.47, 0.25 to 0.88, p = .018) was associated with favorable outcomes.

CONCLUSION

Different COVID-19 outcomes in people with SLE are mostly driven by COVID-19 vaccination, medications, and activity SLE. More importantly, three doses of COVID-19 vaccination may be associated with better outcomes.

Concurrent Administration of COVID-19 and Influenza Vaccines Enhances Spike-Specific Antibody Responses

Background

The bivalent COVID-19 mRNA boosters became available in fall 2022 and were recommended alongside the seasonal influenza vaccine. However, the immunogenicity of concurrent vs separate administration of these vaccines remains unclear.

Methods

Here, we analyzed antibody responses in health care workers who received the bivalent COVID-19 booster and the influenza vaccine on the same day or on different days through systems serology. Antibody-binding and functional responses were characterized at peak responses and after 6 months following vaccination.

Results

IgG1 and neutralization responses to SARS-CoV-2 XBB.1.5 were higher at peak and after 6 months following concurrent administration as compared with separate administration of the COVID-19 and influenza vaccines. While similar results were not observed for influenza responses, no interference was noted with concurrent administration.

Conclusions

These data suggest that concurrent administration of these vaccines may yield higher and more durable SARS-CoV-2 neutralizing antibody responses while maintaining responses against influenza.

Inverse association with COVID-19 vaccination status of the incidence of pneumonia after SARS-CoV-2 infection: A nationwide retrospective cohort study

BACKGROUND

Although one of the characteristics of COVID-19 is accompanied by acute pneumonia immediately after infection, large-scale cohort studies focused on this issue are lacking. In addition, there is interest in how COVID-19 vaccinations reduce the incidence of acute pneumonia for people infected with different strains of SARS-CoV-2. Thus, we assess the short-term incidence of pneumonia after COVID-19 with the vaccination and SARS-CoV-2 variants.

METHODS

As data for 2136,751 COVID-19 patients between January 01, 2020 and February 28, 2022 was collected, they were observed for one month from the day of infection. Patients in retrospective cohort study were classified according to doses of the received vaccine and the epidemic phase when SARS-CoV-2 variants prevailed. Multivariable logistic regression analysis calculated adjusted odds ratios (aOR) and 95% confidence intervals (CIs) for the pneumonia risk.

RESULTS

In B.1.1.7-B.1.351, B.1.617.2, and B.1.617.2 variants, the aORs (95% CIs; p-value) for incidence of pneumonia were 0.93 (0.89-0.98; <0.001), 0.74 (0.70-0.78; <0.001), and 0.04 (0.038-0.043; <0.001), respectively, compared to the original strain. More than 80% of patients have received the second and more doses of the vaccine (average age=44.67 years). The aORs (95% CIs; p-value) for pneumonia were 0.61 (0.58-0.64; <0.001), 0.39 (0.38-0.40; <0.001), and 0.18 (0.166-0.184; <0.001) in patients who received the first (N = 68,216), second (N = 898,838), and ≥ third doses (N = 836,173), respectively, compared to unvaccinated patients. According to the received vaccine (second dose of mRNA or viral vector), those who received BNT162b2 and mRNA-1273 (N = 787,980) had lower risk of pneumonia, compared to that in those who received h ChAdOx1 nCov-19 and AD26. COV2-S (N = 89,024).

CONCLUSIONS

Our findings suggest that the second and ≥ third doses (61% and 82% of risk aversion effect increased, respectively) of the COVID-19 vaccine can prevent the COVID-19-related pneumonia, regardless of the variants.

The protective effect of intranasal immunization with influenza virus recombinant adenovirus vaccine on mucosal and systemic immune response

Influenza virus is a kind of virus that poses several hazards of animal and human health. Therefore, it is important to develop an effective vaccine to prevent influenza. To this end we successfully packaged recombinant adenovirus rAd-NP-M2e-GFP expressing multiple copies of influenza virus conserved antigens NP and M2e and packaged empty vector adenovirus rAd-GFP. The effect of rAd-NP-M2e-GFP on the activation of dendritic cell (DC) in vitro and in vivo was detected by intranasal immunization. The results showed that rAd-NP-M2e-GFP promoted the activation of DC in vitro and in vivo. After the primary immunization and booster immunization of mice through the nasal immune way, the results showed that rAd-NP-M2e-GFP induced enhanced local mucosal-specific T cell responses, increased the content of SIgA in broncho alveolar lavage fluids (BALF) and triggered the differentiation of B cells in the germinal center. It is proved that rAd-NP-M2e-GFP can significantly elicit mucosal immunity and systemic immune response. In addition, rAd-NP-M2e-GFP could effectively protect mice after H1N1 influenza virus challenge. To lay the foundation and provide reference for further development of influenza virus mucosal vaccine in the future.

Clearance of persistent SARS-CoV-2 associates with increased neutralizing antibodies in advanced HIV disease post-ART initiation

SARS-CoV-2 clearance requires adaptive immunity but the contribution of neutralizing antibodies and T cells in different immune states is unclear. Here we ask which adaptive immune responses associate with clearance of long-term SARS-CoV-2 infection in HIV-mediated immunosuppression after suppressive antiretroviral therapy (ART) initiation. We assembled a cohort of SARS-CoV-2 infected people in South Africa (n = 994) including participants with advanced HIV disease characterized by immunosuppression due to T cell depletion. Fifty-four percent of participants with advanced HIV disease had prolonged SARS-CoV-2 infection (>1 month). In the five vaccinated participants with advanced HIV disease tested, SARS-CoV-2 clearance associates with emergence of neutralizing antibodies but not SARS-CoV-2 specific CD8 T cells, while CD4 T cell responses were not determined due to low cell numbers. Further, complete HIV suppression is not required for clearance, although it is necessary for an effective vaccine response. Persistent SARS-CoV-2 infection led to SARS-CoV-2 evolution, including virus with extensive neutralization escape in a Delta variant infected participant. The results provide evidence that neutralizing antibodies are required for SARS-CoV-2 clearance in HIV-mediated immunosuppression recovery, and that suppressive ART is necessary to curtail evolution of co-infecting pathogens to reduce individual health consequences as well as public health risk linked with generation of escape mutants.

Nanotechnology of inhalable vaccines for enhancing mucosal immunity

Vaccines are the cornerstone of world health. The majority of vaccines are formulated as injectable products, facing the drawbacks of cold chain transportation, needle-stick injuries, and primary systemic immunity. Inhalable vaccines exhibited unique advantages due to their small dose, easy to use, quick effect, and simultaneous induction of mucosal and systemic responses. Facing global pandemics, especially the coronavirus disease 2019 (COVID-19), a majority of inhalable vaccines are in preclinical or clinical trials. A better understanding of advanced delivery technologies of inhalable vaccines may provide new scientific insights for developing inhalable vaccines. In this review article, detailed immune mechanisms involving mucosal, cellular, and humoral immunity were described. The preparation methods of inhalable vaccines were then introduced. Advanced nanotechnologies of inhalable vaccines containing inhalable nucleic acid vaccines, inhalable adenovirus vector vaccines, novel adjuvant-assisted inhalable vaccines, and biomaterials for inhalable vaccine delivery were emphatically discussed. Meanwhile, the latest clinical progress in inhalable vaccines for COVID-19 and tuberculosis was discussed.

Autoimmune response after SARS-CoV-2 infection and SARS-CoV-2 vaccines

The complicated relationships between autoimmunity, COVID-19, and COVID-19 vaccinations are described, giving insight into their intricacies. Antinuclear antibodies (ANA), anti-Ro/SSA, rheumatoid factor, lupus anticoagulant, and antibodies against interferon (IFN)-I have all been consistently found in COVID-19 patients, indicating a high prevalence of autoimmune reactions following viral exposure. Furthermore, the discovery of human proteins with structural similarities to SARS-CoV-2 peptides as possible autoantigens highlights the complex interplay between the virus and the immune system in initiating autoimmunity. An updated summary of the current status of COVID-19 vaccines is presented. We present probable pathways underpinning the genesis of COVID-19 autoimmunity, such as bystander activation caused by hyperinflammatory conditions, viral persistence, and the creation of neutrophil extracellular traps. These pathways provide important insights into the development of autoimmune-related symptoms ranging from organ-specific to systemic autoimmune and inflammatory illnesses, demonstrating the wide influence of COVID-19 on the immune system.

Recurring SARS-CoV-2 variants: an update on post-pandemic, co-infections and immune response

The post-pandemic era following the global spread of the SARS-CoV-2 virus has brought about persistent concerns regarding recurring coinfections. While significant strides in genome mapping, diagnostics, and vaccine development have controlled the pandemic and reduced fatalities, ongoing virus mutations necessitate a deeper exploration of the interplay between SARS-CoV-2 mutations and the host's immune response. Various vaccines, including RNA-based ones like Pfizer and Moderna, viral vector vaccines like Johnson & Johnson and AstraZeneca, and protein subunit vaccines like Novavax, have played critical roles in mitigating the impact of COVID-19. Understanding their strengths and limitations is crucial for tailoring future vaccines to specific variants and individual needs. The intricate relationship between SARS-CoV-2 mutations and the immune response remains a focus of intense research, providing insights into personalized treatment strategies and long-term effects like long-COVID. This article offers an overview of the post-pandemic landscape, highlighting emerging variants, summarizing vaccine platforms, and delving into immunological responses and the phenomenon of long-COVID. By presenting clinical findings, it aims to contribute to the ongoing understanding of COVID-19's progression in the aftermath of the pandemic.

Prefusion-stabilized SARS-CoV-2 S2-only antigen provides protection against SARS-CoV-2 challenge

Ever-evolving SARS-CoV-2 variants of concern (VOCs) have diminished the effectiveness of therapeutic antibodies and vaccines. Developing a coronavirus vaccine that offers a greater breadth of protection against current and future VOCs would eliminate the need to reformulate COVID-19 vaccines. Here, we rationally engineer the sequence-conserved S2 subunit of the SARS-CoV-2 spike protein and characterize the resulting S2-only antigens. Structural studies demonstrate that the introduction of interprotomer disulfide bonds can lock S2 in prefusion trimers, although the apex samples a continuum of conformations between open and closed states. Immunization with prefusion-stabilized S2 constructs elicits broadly neutralizing responses against several sarbecoviruses and protects female BALB/c mice from mouse-adapted SARS-CoV-2 lethal challenge and partially protects female BALB/c mice from mouse-adapted SARS-CoV lethal challenge. These engineering and immunogenicity results should inform the development of next-generation pan-coronavirus therapeutics and vaccines.

Mucosal boosting enhances vaccine protection against SARS-CoV-2 in macaques

A limitation of current SARS-CoV-2 vaccines is that they provide minimal protection against infection with current Omicron subvariants1,2, although they still provide protection against severe disease. Enhanced mucosal immunity may be required to block infection and onward transmission. Intranasal administration of current vaccines has proven inconsistent3-7, suggesting that alternative immunization strategies may be required. Here we show that intratracheal boosting with a bivalent Ad26-based SARS-CoV-2 vaccine results in substantial induction of mucosal humoral and cellular immunity and near-complete protection against SARS-CoV-2 BQ.1.1 challenge. A total of 40 previously immunized rhesus macaques were boosted with a bivalent Ad26 vaccine by the intramuscular, intranasal and intratracheal routes, or with a bivalent mRNA vaccine by the intranasal route. Ad26 boosting by the intratracheal route led to a substantial expansion of mucosal neutralizing antibodies, IgG and IgA binding antibodies, and CD8+ and CD4+ T cell responses, which exceeded those induced by Ad26 boosting by the intramuscular and intranasal routes. Intratracheal Ad26 boosting also led to robust upregulation of cytokine, natural killer, and T and B cell pathways in the lungs. After challenge with a high dose of SARS-CoV-2 BQ.1.1, intratracheal Ad26 boosting provided near-complete protection, whereas the other boosting strategies proved less effective. Protective efficacy correlated best with mucosal humoral and cellular immune responses. These data demonstrate that these immunization strategies induce robust mucosal immunity, suggesting the feasibility of developing vaccines that block respiratory viral infections.

Protective effect of vaccination on the risk of cardiovascular disease after SARS-CoV-2 infection

OBJECTIVE

This study investigated the incidence of CVDs after COVID-19.

METHODS

Data for 2,146,130 infected people were collected, including the vaccination status. COVID-19 patients were classified according to the number of the received vaccine doses: no, first, second, and ≥ third. To evaluate the short-term risk of CVDs after infection, adjusted odds ratios (aOR) and 95% confidence intervals (CIs) were calculated by multivariable logistic regression analysis after adjustments for covariates.

RESULTS

Compared to non-infected people, aORs [95% CIs; p value] for CVDs within a month after infection were 2.80 [2.64-2.97; < 0.001] in overall infected people and 4.62 [4.23-5.05; < 0.001], 4.20 [3.45-5.11; < 0.001], 2.79 [2.55-3.05; < 0.001], and 2.07 [1.91-2.24; < 0.001] in those who were infected after receiving no, first, second, and ≥ third vaccine doses, respectively. Among participants who received second doses of vaccine prior to contracting COVID-19, the aOR in those vaccinated with only the mRNA-based vaccine (BNT162b2 and mRNA-1273; Reference) was lower than those vaccinated with the virus-derived vaccine (ChAdOx1 nCov-19 and AD26.COV2-S; aOR 1.25 [1.06-1.48; < 0.01]).

CONCLUSION

Although COVID-19 increased the CVD risk, the inverse association in the risk of CVDs according to vaccine doses was significant in a dose-response manner. Our findings suggest that ≥ second doses of the COVID-19 vaccine prevent the risk of CVDs after SARS-CoV-2 infection.

COVID-19 Vaccines: Where Did We Stand at the End of 2023?

Vaccine development against SARS-CoV-2 has been highly successful in slowing down the COVID-19 pandemic. A wide spectrum of approaches including vaccines based on whole viruses, protein subunits and peptides, viral vectors, and nucleic acids has been developed in parallel. For all types of COVID-19 vaccines, good safety and efficacy have been obtained in both preclinical animal studies and in clinical trials in humans. Moreover, emergency use authorization has been granted for the major types of COVID-19 vaccines. Although high safety has been demonstrated, rare cases of severe adverse events have been detected after global mass vaccinations. Emerging SARS-CoV-2 variants possessing enhanced infectivity have affected vaccine protection efficacy requiring re-design and re-engineering of novel COVID-19 vaccine candidates. Furthermore, insight is given into preparedness against emerging SARS-CoV-2 variants.

Caveats of chimpanzee ChAdOx1 adenovirus-vectored vaccines to boost anti-SARS-CoV-2 protective immunity in mice

Several COVID-19 vaccines use adenovirus vectors to deliver the SARS-CoV-2 spike (S) protein. Immunization with these vaccines promotes immunity against the S protein, but against also the adenovirus itself. This could interfere with the entry of the vaccine into the cell, reducing its efficacy. Herein, we evaluate the efficiency of an adenovirus-vectored vaccine (chimpanzee ChAdOx1 adenovirus, AZD1222) in boosting the specific immunity compared to that induced by a recombinant receptor-binding domain (RBD)-based vaccine without viral vector. Mice immunized with the AZD1222 human vaccine were given a booster 6 months later, with either the homologous vaccine or a recombinant vaccine based on RBD of the delta variant, which was prevalent at the start of this study. A significant increase in anti-RBD antibody levels was observed in rRBD-boosted mice (31-61%) compared to those receiving two doses of AZD1222 (0%). Significantly higher rates of PepMix™- or RBD-elicited proliferation were also observed in IFNγ-producing CD4 and CD8 cells from mice boosted with one or two doses of RBD, respectively. The lower efficiency of the ChAdOx1-S vaccine in boosting specific immunity could be the result of a pre-existing anti-vector immunity, induced by increased levels of anti-adenovirus antibodies found both in mice and humans. Taken together, these results point to the importance of avoiding the recurrent use of the same adenovirus vector in individuals with immunity and memory against them. It also illustrates the disadvantages of ChAdOx1 adenovirus-vectored vaccine with respect to recombinant protein vaccines, which can be used without restriction in vaccine-booster programs. KEY POINTS: • ChAdOx1 adenovirus vaccine (AZD1222) may not be effective in boosting anti-SARS-CoV-2 immunity • A recombinant RBD protein vaccine is effective in boosting anti-SARS-CoV-2 immunity in mice • Antibodies elicited by the rRBD-delta vaccine persisted for up to 3 months in mice.

Current Progress of Severe Fever with Thrombocytopenia Syndrome Virus (SFTSV) Vaccine Development

SFTSV is an emerging tick-borne virus causing hemorrhagic fever with a case fatality rate (CFR) that can reach up to 27%. With endemic infection in East Asia and the recent spread of the vector tick to more than 20 states in the United States, the SFTSV outbreak is a globally growing public health concern. However, there is currently no targeted antiviral therapy or licensed vaccine against SFTSV. Considering the age-dependent SFTS pathogenesis and disease outcome, a sophisticated vaccine development approach is required to safeguard the elderly population from lethal SFTSV infection. Given the recent emergence of SFTSV, the establishment of animal models to study immunogenicity and protection from SFTS symptoms has only occurred recently. The latest research efforts have applied diverse vaccine development approaches-including live-attenuated vaccine, DNA vaccine, whole inactivated virus vaccine, viral vector vaccine, protein subunit vaccine, and mRNA vaccine-in the quest to develop a safe and effective vaccine against SFTSV. This review aims to outline the current progress in SFTSV vaccine development and suggest future directions to enhance the safety and efficacy of these vaccines, ensuring their suitability for clinical application.

Safety, Immunogenicity, and Regimen Selection of Ad26.RSV.preF-Based Vaccine Combinations: A Randomized, Double-blind, Placebo-Controlled, Phase 1/2a Study

BACKGROUND

Ad26.RSV.preF is an adenovirus serotype 26 vector-based respiratory syncytial virus (RSV) vaccine encoding a prefusion conformation-stabilized RSV fusion protein (preF) that demonstrated robust humoral and cellular immunogenicity and showed promising efficacy in a human challenge study in younger adults. Addition of recombinant RSV preF protein might enhance RSV-specific humoral immune responses, especially in older populations.

METHODS

This randomized, double-blind, placebo-controlled, phase 1/2a study compared the safety and immunogenicity of Ad26.RSV.preF alone and varying doses of Ad26.RSV.preF-RSV preF protein combinations in adults aged ≥60 years. This report includes data from cohort 1 (initial safety, n = 64) and cohort 2 (regimen selection, n = 288). Primary immunogenicity and safety analyses were performed 28 days postvaccination (cohort 2) for regimen selection.

RESULTS

All vaccine regimens were well tolerated, with similar reactogenicity profiles among them. Combination regimens induced greater humoral immune responses (virus-neutralizing and preF-specific binding antibodies) and similar cellular ones (RSV-F-specific T cells) as compared with Ad26.RSV.preF alone. Vaccine-induced immune responses remained above baseline up to 1.5 years postvaccination.

CONCLUSIONS

All Ad26.RSV.preF-based regimens were well tolerated. A combination regimen comprising Ad26.RSV.preF, which elicits strong humoral and cellular responses, and RSV preF protein, which increases humoral responses, was selected for further development. Clinical Trials Registration. NCT03502707.

MA, Tovar-Rosero YY, Oñate AA, O'Ryan M. Two centuries of vaccination: historical and conceptual approach and future perspectives

Over the past two centuries, vaccines have been critical for the prevention of infectious diseases and are considered milestones in the medical and public health history. The World Health Organization estimates that vaccination currently prevents approximately 3.5-5 million deaths annually, attributed to diseases such as diphtheria, tetanus, pertussis, influenza, and measles. Vaccination has been instrumental in eradicating important pathogens, including the smallpox virus and wild poliovirus types 2 and 3. This narrative review offers a detailed journey through the history and advancements in vaccinology, tailored for healthcare workers. It traces pivotal milestones, beginning with the variolation practices in the early 17th century, the development of the first smallpox vaccine, and the continuous evolution and innovation in vaccine development up to the present day. We also briefly review immunological principles underlying vaccination, as well as the main vaccine types, with a special mention of the recently introduced mRNA vaccine technology. Additionally, we discuss the broad benefits of vaccines, including their role in reducing morbidity and mortality, and in fostering socioeconomic development in communities. Finally, we address the issue of vaccine hesitancy and discuss effective strategies to promote vaccine acceptance. Research, collaboration, and the widespread acceptance and use of vaccines are imperative for the continued success of vaccination programs in controlling and ultimately eradicating infectious diseases.

Influence of Seasonality and Public-Health Interventions on the COVID-19 Pandemic in Northern Europe

BACKGROUND

Most government efforts to control the COVID-19 pandemic revolved around non-pharmaceutical interventions (NPIs) and vaccination. However, many respiratory diseases show distinctive seasonal trends. In this manuscript, we examined the contribution of these three factors to the progression of the COVID-19 pandemic.

METHODS

Pearson correlation coefficients and time-lagged analysis were used to examine the relationship between NPIs, vaccinations and seasonality (using the average incidence of endemic human beta-coronaviruses in Sweden over a 10-year period as a proxy) and the progression of the COVID-19 pandemic as tracked by deaths; cases; hospitalisations; intensive care unit occupancy and testing positivity rates in six Northern European countries (population 99.12 million) using a population-based, observational, ecological study method.

FINDINGS

The waves of the pandemic correlated well with the seasonality of human beta-coronaviruses (HCoV-OC43 and HCoV-HKU1). In contrast, we could not find clear or consistent evidence that the stringency of NPIs or vaccination reduced the progression of the pandemic. However, these results are correlations and not causations.

IMPLICATIONS

We hypothesise that the apparent influence of NPIs and vaccines might instead be an effect of coronavirus seasonality. We suggest that policymakers consider these results when assessing policy options for future pandemics.

LIMITATIONS

The study is limited to six temperate Northern European countries with spatial and temporal variations in metrics used to track the progression of the COVID-19 pandemic. Caution should be exercised when extrapolating these findings.

Dissecting the Heterogeneous Glycan Profiles of Recombinant Coronavirus Spike Proteins with Individual Ion Mass Spectrometry

Surface-embedded glycoproteins, such as the spike protein trimers of coronaviruses MERS, SARS-CoV, and SARS-CoV-2, play a key role in viral function and are the target antigen for many vaccines. However, their significant glycan heterogeneity poses an analytical challenge. Here, we utilized individual ion mass spectrometry (I2MS), a multiplexed charge detection measurement with similarities to charge detection mass spectrometry (CDMS), in which a commercially available Orbitrap analyzer is used to directly produce mass profiles of these heterogeneous coronavirus spike protein trimers under native-like conditions. Analysis by I2MS shows that glycosylation contributes to the molecular mass of each protein trimer more significantly than expected by bottom-up techniques, highlighting the importance of obtaining complementary intact mass information when characterizing glycosylation of such heterogeneous proteins. Enzymatic dissection to remove sialic acid or N-linked glycans demonstrates that I2MS can be used to better understand the glycan profile from a native viewpoint. Deglycosylation of N-glycans followed by I2MS analysis indicates that the SARS-CoV-2 spike protein trimer contains glycans that are more difficult to remove than its MERS and SARS-CoV counterparts, and these differences are correlated with solvent accessibility. I2MS technology enables characterization of protein mass and intact glycan profile and is orthogonal to traditional mass analysis methods such as size exclusion chromatography-multiangle light scattering (SEC-MALS) and field flow fractionation-multiangle light scattering (FFF-MALS). An added advantage of I2MS is low sample use, requiring 100-fold less than other methodologies. This work highlights how I2MS technology can enable efficient development of vaccines and therapeutics for pharmaceutical development.

Nucleic acid degradation as barrier to gene delivery: a guide to understand and overcome nuclease activity

Gene therapy is on its way to revolutionize the treatment of both inherited and acquired diseases, by transferring nucleic acids to correct a disease-causing gene in the target cells of patients. In the fight against infectious diseases, mRNA-based therapeutics have proven to be a viable strategy in the recent Covid-19 pandemic. Although a growing number of gene therapies have been approved, the success rate is limited when compared to the large number of preclinical and clinical trials that have been/are being performed. In this review, we highlight some of the hurdles which gene therapies encounter after administration into the human body, with a focus on nucleic acid degradation by nucleases that are extremely abundant in mammalian organs, biological fluids as well as in subcellular compartments. We overview the available strategies to reduce the biodegradation of gene therapeutics after administration, including chemical modifications of the nucleic acids, encapsulation into vectors and co-administration with nuclease inhibitors and discuss which strategies are applied for clinically approved nucleic acid therapeutics. In the final part, we discuss the currently available methods and techniques to qualify and quantify the integrity of nucleic acids, with their own strengths and limitations.

A quest for universal anti-SARS-CoV-2 T cell assay: systematic review, meta-analysis, and experimental validation

Measuring SARS-CoV-2-specific T cell responses is crucial to understanding an individual's immunity to COVID-19. However, high inter- and intra-assay variability make it difficult to define T cells as a correlate of protection against COVID-19. To address this, we performed systematic review and meta-analysis of 495 datasets from 94 original articles evaluating SARS-CoV-2-specific T cell responses using three assays - Activation Induced Marker (AIM), Intracellular Cytokine Staining (ICS), and Enzyme-Linked Immunospot (ELISPOT), and defined each assay's quantitative range. We validated these ranges using samples from 193 SARS-CoV-2-exposed individuals. Although IFNγ ELISPOT was the preferred assay, our experimental validation suggested that it under-represented the SARS-CoV-2-specific T cell repertoire. Our data indicate that a combination of AIM and ICS or FluoroSpot assay would better represent the frequency, polyfunctionality, and compartmentalization of the antigen-specific T cell responses. Taken together, our results contribute to defining the ranges of antigen-specific T cell assays and propose a choice of assay that can be employed to better understand the cellular immune response against viral diseases.

Therapeutic Challenges in COVID-19

SARS-CoV2 is a novel respiratory coronavirus and, understanding its molecular mechanism is a prerequisite to developing effective treatment for COVID-19. This RNA genome-carrying virus has a protein coat with spikes (S) that attaches to the ACE2 receptor at the cell surface of human cells. Several repurposed drugs are used to treat COVID-19 patients that are proven to be largely unsuccessful or have limited success in reducing mortalities. Several vaccines are in use to reduce the viral load to prevent developing symptoms. Major challenges to their efficacy include the inability of antibody molecules to enter cells but remain effective in the bloodstream to kill the virus. The efficacy of vaccines also depends on their neutralizing ability to constantly evolve new virus strains due to novel mutations and evolutionary survival dynamics. Taken together, SARS-CoV2 antibody vaccines may not be very effective and other approaches based on genetic, genomic, and protein interactome could be fruitful to identify therapeutic targets to reduce disease-related mortalities.

Discovery and development of COVID-19 vaccine from laboratory to clinic

The world has recently experienced one of the biggest and most severe public health disasters with severe acute respiratory syndrome coronavirus (SARS-CoV-2). SARS-CoV-2 is responsible for the coronavirus disease of 2019 (COVID-19) which is one of the most widespread and powerful infections affecting human lungs. Current figures show that the epidemic had reached 216 nations, where it had killed about 6,438,926 individuals and infected 590,405,710. WHO proclaimed the outbreak of the Ebola virus disease (EVD), in 2014 that killed hundreds of people in West Africa. The development of vaccines for SARS-CoV-2 becomes more difficult due to the viral mutation in its non-structural proteins (NSPs) especially NSP2 and NSP3, S protein, and RNA-dependent RNA polymerase (RdRp). Continuous monitoring of SARS-CoV-2, dynamics of the genomic sequence, and spike protein mutations are very important for the successful development of vaccines with good efficacy. Hence, the vaccine development for SARS-CoV-2 faces specific challenges starting from viral mutation. The requirement of long-term immunity development, safety, efficacy, stability, vaccine allocation, distribution, and finally, its cost is discussed in detail. Currently, 169 vaccines are in the clinical development stage, while 198 vaccines are in the preclinical development stage. The majority of these vaccines belong to the Ps-Protein subunit type which has 54, and the minor BacAg-SPV (Bacterial antigen-spore expression vector) type, at least 1 vaccination. The use of computational methods and models for vaccine development has revolutionized the traditional methods of vaccine development. Further, this updated review highlights the upcoming vaccine development strategies in response to the current pandemic and post-pandemic era, in the field of vaccine development.

Clinical trials of pharmacological interventions for SARS-CoV-2 published in leading medical journals report adherence but not how it was assessed

AIMS

Adherence to pharmacological interventions in clinical trials is crucial for accurate identification of beneficial and adverse outcomes. The ways in which adherence to interventions should be reported in trial publications are described in the Template for Intervention Description and Replication (TIDieR), a 12-item extension of the Consolidated Standards of Reporting Trials reporting guidelines. The objective of this study was to assess compliance with TIDieR Items 11 and 12 of randomized controlled trials (RCTs) of interventions in SARS-CoV-2 infection published in 5 selected journals during 2021.

METHODS

We assessed pharmacological interventions for SARS-CoV-2 infection reported in RCTs published in 2021 in the Annals of Internal Medicine, The BMJ, JAMA, The Lancet and The New England Journal for Medicine for compliance with TIDieR items addressing intervention adherence (Items 11 and 12). We calculated proportional adherence for pharmacological and comparator interventions where available.

RESULTS

We found 75 eligible RCTs. Twenty-eight (37%) reported results of SARS-CoV-2 vaccinations. Compliance with Items 11 and 12 could be assessed in 71 of these 75. Of the 71 RCTs, 37 (52%) reported how adherence was assessed (Item 11), and 70 reported adherence rates (Item 12). Only 1 of the 71 RCTs (1.4%, 0-7.6%) fully complied with TIDieR Items 11 and 12.

CONCLUSION

Half of RCTs of SARS-CoV-2 pharmacological interventions published in leading medical journals in 2021 complied with reporting of how adherence assessments were made and almost none complied with both TIDieR Items 11 and 12. The implications for interpretation, application and replication of findings based on these publications warrant consideration.

A broadly reactive antibody targeting the N-terminal domain of SARS-CoV-2 spike confers Fc-mediated protection

Most neutralizing anti-SARS-CoV-2 monoclonal antibodies (mAbs) target the receptor binding domain (RBD) of the spike (S) protein. Here, we characterize a panel of mAbs targeting the N-terminal domain (NTD) or other non-RBD epitopes of S. A subset of NTD mAbs inhibits SARS-CoV-2 entry at a post-attachment step and avidly binds the surface of infected cells. One neutralizing NTD mAb, SARS2-57, protects K18-hACE2 mice against SARS-CoV-2 infection in an Fc-dependent manner. Structural analysis demonstrates that SARS2-57 engages an antigenic supersite that is remodeled by deletions common to emerging variants. In neutralization escape studies with SARS2-57, this NTD site accumulates mutations, including a similar deletion, but the addition of an anti-RBD mAb prevents such escape. Thus, our study highlights a common strategy of immune evasion by SARS-CoV-2 variants and how targeting spatially distinct epitopes, including those in the NTD, may limit such escape.

Evolving spike-protein N-glycosylation in SARS-CoV-2 variants

Since >3 years, SARS-CoV-2 has plunged humans into a colossal pandemic. Henceforth, multiple waves of infection have swept through the human population, led by variants that were able to partially evade acquired immunity. The co-evolution of SARS-CoV-2 variants with human immunity provides an excellent opportunity to study the interaction between viral pathogens and their human hosts. The heavily N-glycosylated spike-protein of SARS-CoV-2 plays a pivotal role in initiating infection and is the target for host immune-response, both of which are impacted by host-installed N-glycans. Using highly-sensitive DeGlyPHER approach, we compared the N-glycan landscape on spikes of the SARS-CoV-2 Wuhan-Hu-1 strain to seven WHO-defined variants of concern/interest, using recombinantly expressed, soluble spike-protein trimers, sharing same stabilizing-mutations. We found that N-glycan processing is conserved at most sites. However, in multiple variants, processing of N-glycans from high mannose- to complex-type is reduced at sites N165, N343 and N616, implicated in spike-protein function.

Predicting COVID-19 pandemic waves including vaccination data with deep learning

Introduction

During the recent COVID-19 pandemics, many models were developed to predict the number of new infections. After almost a year, models had also the challenge to include information about the waning effect of vaccines and by infection, and also how this effect start to disappear.

Methods

We present a deep learning-based approach to predict the number of daily COVID-19 cases in 30 countries, considering the non-pharmaceutical interventions (NPIs) applied in those countries and including vaccination data of the most used vaccines.

Results

We empirically validate the proposed approach for 4 months between January and April 2021, once vaccination was available and applied to the population and the COVID-19 variants were closer to the one considered for developing the vaccines. With the predictions of new cases, we can prescribe NPIs plans that present the best trade-off between the expected number of COVID-19 cases and the social and economic cost of applying such interventions.

Discussion

Whereas, mathematical models which include the effect of vaccines in the spread of the SARS-COV-2 pandemic are available, to the best of our knowledge we are the first to propose a data driven method based on recurrent neural networks that considers the waning effect of the immunization acquired either by vaccine administration or by recovering from the illness. This work contributes with an accurate, scalable, data-driven approach to modeling the pandemic curves of cases when vaccination data is available.

Self-assembling Gn head ferritin nanoparticle vaccine provides full protection from lethal challenge of Dabie Bandavirus in aged ferrets

Dabie Bandavirus (DBV), previously known as Severe Fever with Thrombocytopenia Syndrome (SFTS) Virus, induces a characteristic thrombocytopenia with a mortality rate ranging from 12% to as high as 30%. The sero-prevalence of DBV in healthy people is not significantly different among age groups, but clinically diagnosed SFTS patients are older than ~50 years, suggesting that age is the critical risk factor for SFTS morbidity and mortality. Accordingly, our immune-competent ferret model demonstrates an age (>4 years old)-dependent DBV infection and pathogenesis that fully recapitulates human clinical manifestation. To protect the aged population from DBV-induced SFTS, vaccine should carry robust immunogenicity with high safety profile. Previous studies have shown that glycoproteins Gn/Gc are the most effective antigens for inducing both neutralizing antibody (NAb)- and T cell-mediated immunity and, thereby, protection. Here, we report the development of a protein subunit vaccine with 24-mer self-assembling ferritin (FT) nanoparticle to present DBV Gn head region (GnH) for enhanced immunogenicity. Anion exchange chromatography and size exclusion chromatography readily purified the GnH-FT nanoparticles to homogeneity with structural integrity. Mice immunized with GnH-FT nanoparticles induced robust NAb response and T-cell immunity against DBV Gn. Furthermore, aged ferrets immunized with GnH-FT nanoparticles were fully protected from DBV challenge without SFTS symptoms such as body weight loss, thrombocytopenia, leukopenia, and fatality. This study demonstrates that DBV GnH-FT nanoparticles provide an efficient vaccine efficacy in mouse and aged ferret models and should be an outstanding vaccine candidate targeted for the aged population against fatal DBV infection.

Evolution and neutralization escape of the SARS-CoV-2 BA.2.86 subvariant

Omicron BA.2.86 subvariant differs from Omicron BA.2 as well as recently circulating variants by over 30 mutations in the spike protein alone. Here we report on the isolation of the live BA.2.86 subvariant from a diagnostic swab collected in South Africa which we tested for escape from neutralizing antibodies and viral replication properties in cell culture. We found that BA.2.86 does not have significantly more escape relative to Omicron XBB.1.5 from neutralizing immunity elicited by either Omicron XBB-family subvariant infection or from residual neutralizing immunity of recently collected sera from the South African population. BA.2.86 does have extensive escape relative to ancestral virus with the D614G substitution (B.1 lineage) when neutralized by sera from pre-Omicron vaccinated individuals and relative to Omicron BA.1 when neutralized by sera from Omicron BA.1 infected individuals. BA.2.86 and XBB.1.5 show similar viral infection dynamics in the VeroE6-TMPRSS2 and H1299-ACE2 cell lines. We also investigate the relationship of BA.2.86 to BA.2 sequences. The closest BA.2 sequences are BA.2 samples from Southern Africa circulating in early 2022. Similarly, many basal BA.2.86 sequences were sampled in Southern Africa. This suggests that BA.2.86 potentially evolved in this region, and that unobserved evolution led to escape from neutralizing antibodies similar in scale to recently circulating strains of SARS-CoV-2.

Novel Spike-stabilized trimers with improved production protect K18-hACE2 mice and golden Syrian hamsters from the highly pathogenic SARS-CoV-2 Beta variant

Most COVID-19 vaccines are based on the SARS-CoV-2 Spike glycoprotein (S) or their subunits. However, S shows some structural instability that limits its immunogenicity and production, hampering the development of recombinant S-based vaccines. The introduction of the K986P and V987P (S-2P) mutations increases the production and immunogenicity of the recombinant S trimer, suggesting that these two parameters are related. Nevertheless, S-2P still shows some molecular instability and it is produced with low yield. Here we described a novel set of mutations identified by molecular modeling and located in the S2 region of the S-2P that increase its production up to five-fold. Besides their immunogenicity, the efficacy of two representative S-2P-based mutants, S-29 and S-21, protecting from a heterologous SARS-CoV-2 Beta variant challenge was assayed in K18-hACE2 mice (an animal model of severe SARS-CoV-2 disease) and golden Syrian hamsters (GSH) (a moderate disease model). S-21 induced higher level of WH1 and Delta variants neutralizing antibodies than S-2P in K18-hACE2 mice three days after challenge. Viral load in nasal turbinate and oropharyngeal samples were reduced in S-21 and S-29 vaccinated mice. Despite that, only the S-29 protein protected 100% of K18-hACE2 mice from severe disease. When GSH were analyzed, all immunized animals were protected from disease development irrespectively of the immunogen they received. Therefore, the higher yield of S-29, as well as its improved immunogenicity and efficacy protecting from the highly pathogenic SARS-CoV-2 Beta variant, pinpoint the S-29 mutant as an alternative to the S-2P protein for future SARS-CoV-2 vaccine development.

Evolving Horizons: Adenovirus Vectors' Timeless Influence on Cancer, Gene Therapy and Vaccines

Efficient and targeted delivery of a DNA payload is vital for developing safe gene therapy. Owing to the recent success of commercial oncolytic vector and multiple COVID-19 vaccines, adenovirus vectors are back in the spotlight. Adenovirus vectors can be used in gene therapy by altering the wild-type virus and making it replication-defective; specific viral genes can be removed and replaced with a segment that holds a therapeutic gene, and this vector can be used as delivery vehicle for tissue specific gene delivery. Modified conditionally replicative-oncolytic adenoviruses target tumors exclusively and have been studied in clinical trials extensively. This comprehensive review seeks to offer a summary of adenovirus vectors, exploring their characteristics, genetic enhancements, and diverse applications in clinical and preclinical settings. A significant emphasis is placed on their crucial role in advancing cancer therapy and the latest breakthroughs in vaccine clinical trials for various diseases. Additionally, we tackle current challenges and future avenues for optimizing adenovirus vectors, promising to open new frontiers in the fields of cell and gene therapies.

Safety and immunogenicity of an inactivated SARS-CoV-2 vaccine (FAKHRAVAC®) in healthy adults aged 18-55 years: Randomized, double-blind, placebo-controlled, phase I clinical trial

Background

The FAKHRAVAC®, an inactivated SARS-CoV-2 vaccine, was assessed for safety and immunogenicity.

Methods and findings

In this double-blind, placebo-controlled, phase I trial, we randomly assigned 135 healthy adults between 18 and 55 to receive vaccine strengths of 5 or 10 μg/dose or placebo (adjuvant only) in 0-14 or 0-21 schedules. This trial was conducted in a single center in a community setting. The safety outcomes in this study were reactogenicity, local and systemic adverse reactions, abnormal laboratory findings, and Medically Attended Adverse Events (MAAE). Immunogenicity outcomes include serum neutralizing antibody activity and specific IgG antibody levels.The most frequent local adverse reaction was tenderness (28.9%), and the most frequent systemic adverse reaction was headache (9.6%). All adverse reactions were mild, occurred at a similar incidence in all six groups, and were resolved within a few days. In the 10-µg/dose vaccine group, the geometric mean ratio for neutralizing antibody titers at two weeks after the second injection compared to the placebo group was 9.03 (95% CI: 3.89-20.95) in the 0-14 schedule and 11.77 (95% CI: 2.77-49.94) in the 0-21 schedule. The corresponding figures for the 5-µg/dose group were 2.74 (1.2-6.28) and 5.2 (1.63-16.55). The highest seroconversion rate (four-fold increase) was related to the 10-µg/dose group (71% and 67% in the 0-14 and 0-21 schedules, respectively).

Conclusions

FAKHRAVAC® is safe and induces a strong humoral immune response to the SARS-CoV-2 virus at 10-µg/dose vaccine strength in adults aged 18-55. This vaccine strength was used for further assessment in the phase II trial.Trial registrationThis study is registered with https://www.irct.ir; IRCT20210206050259N1.

Detection of pre-existing neutralizing antibodies against Ad26 in HIV-1-infected individuals not responding to the Ad26.COV2.S vaccine

PURPOSE

The Ad26.COV2.S vaccine is a replication-incompetent human adenovirus type 26 vector encoding the SARS-CoV-2 spike protein. In a phase 1-2a trial, a single dose of Ad26.COV2.S induced SARS-CoV-2 spike-specific antibodies in ≥ 96% of healthy adults. To investigate vaccine immunogenicity in HIV-1-infection, we measured SARS-CoV-2 spike-specific antibodies in Ad26.COV2.S vaccinated HIV-1-infected patients and analyzed the presence of pre-existing Ad26 neutralizing antibodies.

METHODS

We included all Ad26.COV2.S vaccinated HIV-1-infected patients of Erlangen HIV cohort fulfilling all inclusion criteria. The study cohort consisted of 15 HIV-1-infected patients and three HIV-1-uninfected subjects who received the Ad26.COV2.S vaccine between April and November 2021. Pre-vaccination sera were collected between October 2014 and June 2021, post-vaccination sera between June and December 2021. Neutralizing antibodies towards Ad26 were determined by a FACS-based inhibition assay measuring the expression of SARS-CoV-2 spike and adenoviral proteins in HEK293T cells after in-vitro transduction with Ad26.COV2.S or the control ChAdOx1-S.

RESULTS

Six out of 15 HIV-1-infected patients failed to develop SARS-CoV-2-specific antibodies and four patients developed weak antibody responses after vaccination with Ad26.COV2.S. Pre-vaccination sera of four of the six vaccine non-responders showed neutralizing activity towards Ad26.COV2.S but not toward the ChAdOx1-S vaccine at 1:50 dilution. After Ad26.COV2.S vaccination, 17 of the 18 subjects developed strong Ad26-neutralizing activity and only one of the 18 subjects showed neutralizing activity towards the ChAdOx1-S vaccine.

CONCLUSION

Ad26.COV2.S vaccination showed a high failure rate in HIV-1-infected patients. Pre-existing immunity against Ad26 could be an important contributor to poor vaccine efficacy in a subgroup of patients.

The Therapeutic Monoclonal Antibody Bamlanivimab Does Not Enhance SARS-CoV-2 Infection by FcR-Mediated Mechanisms

As part of the non-clinical safety package characterizing bamlanivimab (SARS-CoV-2 neutralizing monoclonal antibody), the risk profile for antibody-dependent enhancement of infection (ADE) was evaluated in vitro and in an African green monkey (AGM) model of COVID-19. In vitro ADE assays in primary human macrophage, Raji, or THP-1 cells were used to evaluate enhancement of viral infection. Bamlanivimab binding to C1q, FcR, and cell-based effector activity was also assessed. In AGMs, the impact of bamlanivimab pretreatment on viral loads and clinical and histological pathology was assessed to evaluate enhanced SARS-CoV-2 replication or pathology. Bamlanivimab did not increase viral replication in vitro, despite a demonstrated effector function. In vivo, no significant differences were found among the AGM groups for weight, temperature, or food intake. Treatment with bamlanivimab reduced viral loads in nasal and oral swabs and BAL fluid relative to control groups. Viral antigen was not detected in lung tissue from animals treated with the highest dose of bamlanivimab. Bamlanivimab did not induce ADE of SARS-CoV-2 infection in vitro or in an AGM model of infection at any dose evaluated. The findings suggest that high-affinity monoclonal antibodies pose a low risk of mediating ADE in patients and support their safety profile as a treatment of COVID-19 disease.

Durable immunity to SARS-CoV-2 in both lower and upper airways achieved with a gorilla adenovirus (GRAd) S-2P vaccine in non-human primates

SARS-CoV-2 continues to pose a global threat, and current vaccines, while effective against severe illness, fall short in preventing transmission. To address this challenge, there's a need for vaccines that induce mucosal immunity and can rapidly control the virus. In this study, we demonstrate that a single immunization with a novel gorilla adenovirus-based vaccine (GRAd) carrying the pre-fusion stabilized Spike protein (S-2P) in non-human primates provided protective immunity for over one year against the BA.5 variant of SARS-CoV-2. A prime-boost regimen using GRAd followed by adjuvanted S-2P (GRAd+S-2P) accelerated viral clearance in both the lower and upper airways. GRAd delivered via aerosol (GRAd(AE)+S-2P) modestly improved protection compared to its matched intramuscular regimen, but showed dramatically superior boosting by mRNA and, importantly, total virus clearance in the upper airway by day 4 post infection. GrAd vaccination regimens elicited robust and durable systemic and mucosal antibody responses to multiple SARS-CoV-2 variants, but only GRAd(AE)+S-2P generated long-lasting T cell responses in the lung. This research underscores the flexibility of the GRAd vaccine platform to provide durable immunity against SARS-CoV-2 in both the lower and upper airways.

Understanding the implications of under-reporting, vaccine efficiency and social behavior on the post-pandemic spread using physics informed neural networks: A case study of China

In late 2019, the emergence of COVID-19 in Wuhan, China, led to the implementation of stringent measures forming the zero-COVID policy aimed at eliminating transmission. Zero-COVID policy basically aimed at completely eliminating the transmission of COVID-19. However, the relaxation of this policy in late 2022 reportedly resulted in a rapid surge of COVID-19 cases. The aim of this work is to investigate the factors contributing to this outbreak using a new SEIR-type epidemic model with time-dependent level of immunity. Our model incorporates a time-dependent level of immunity considering vaccine doses administered and time-post-vaccination dependent vaccine efficacy. We find that vaccine efficacy plays a significant role in determining the outbreak size and maximum number of daily infected. Additionally, our model considers under-reporting in daily cases and deaths, revealing their combined effects on the outbreak magnitude. We also introduce a novel Physics Informed Neural Networks (PINNs) approach which is extremely useful in estimating critical parameters and helps in evaluating the predictive capability of our model.