A Review of Different Vaccines and Strategies to Combat COVID-19

Evaluation of SARS-CoV-2 anti-Spike antibody levels and breakthrough infection risk among vaccinated adults in North Lebanon

Since March 2020, the COVID-19 pandemic has swiftly propagated, triggering a competitive race among medical firms to forge vaccines that thwart the infection. Lebanon initiated its vaccination campaign on February 14, 2021. Despite numerous studies conducted to elucidate the characteristics of immune responses elicited by vaccination, the topic remains unclear. Here, we aimed to track the progression of anti-spike SARS-CoV-2 antibody titers at two-time points (T1: shortly after the second vaccination dose, T2: six months later) within a cohort of 201 adults who received Pfizer-BioNTech (BNT162b2), AstraZeneca, or Sputnik V vaccines in North Lebanon. Blood specimens were obtained from participants, and antibody titers against SARS-CoV-2 were quantified through the Elecsys-Anti-SARS-CoV-2 S assay (Roche Diagnostics, Switzerland). We used univariate analysis and multivariable logistic regression models to predict determinants influencing the decline in immune response and the occurrence of breakthrough infections among vaccinated patients. Among the 201 participants, 141 exhibited unchanging levels of antibody titers between the two sample collections, 55 displayed waning antibody titers, and only five participants demonstrated heightened antibody levels. Notably, age emerged as the sole variable significantly linked to the waning immune response. Moreover, the BNT162b2 vaccine exhibited significantly higher efficacy concerning the occurrence of breakthrough infections when compared with the AstraZeneca vaccine. Overall, our study reflected the immune status of a sample of vaccinated adults in North Lebanon. Further studies on a larger scale are needed at the national level to follow the immune response after vaccination, especially after the addition of the third vaccination dose.

Stroke Following Coronavirus Disease 2019 Vaccination: Evidence Based on Different Designs of Real-World Studies

BACKGROUND

We aimed to evaluate whether coronavirus disease 2019 (COVID-19) vaccination was associated with stroke.

METHODS

We conducted a systematic meta-analysis of studies using cohort, self-controlled case series (SCCS), and case-crossover study (CCOS) designs to evaluate incidence risk ratios (IRRs) and 95% confidence intervals (CIs) of ischemic stroke (IS), hemorrhagic stroke (HS), and cerebral venous sinus thrombosis (CVST) following COVID-19 vaccination. Risks of stroke were pooled among subpopulations categorized by vaccine type, dose, age, and sex. Sensitivity analysis was performed by different defined risk periods.

RESULTS

Fourteen studies involving 79 918 904 individuals were included. Cohort studies showed decreased risks of IS (IRR, 0.82 [95% CI, .75-.90]) and HS (IRR, 0.75 [95% CI, .67-.85]) postvaccination, but not CVST (IRR, 1.18 [95% CI, .70-1.98]). SCCS identified increased risks 1-21 days postvaccination (IRRIS, 1.05 [95% CI, 1.00-1.10]; IRRHS, 1.16 [95% CI, 1.06-1.26]) or 1-28 days postvaccination (IRRIS, 1.04 [95% CI, 1.00-1.08]; IRRHS, 1.37 [95% CI, 1.15-1.64]), similar to CVST (IRR, 1.58 [95% CI, 1.08-2.32]). CCOS reported an increased risk of CVST after ChAdOx1 vaccination (IRR, 2.9 [95% CI, 1.1-7.2]).

CONCLUSIONS

Although different study designs yielded inconsistent findings, considering the relatively low background incidence of stroke and benefits of vaccination, even a potentially increased risk of stroke postvaccination should not justify vaccine hesitancy.

Aryl hydrocarbon receptor is a proviral host factor and a candidate pan-SARS-CoV-2 therapeutic target

The emergence of a series of SARS-CoV-2 variants has necessitated the search for broad-spectrum antiviral targets. The aryl hydrocarbon receptor (AhR) senses tryptophan metabolites and is an immune regulator. However, the role of AhR in SARS-CoV-2 infection and whether AhR can be used as the target of antiviral therapy against SARS-CoV-2 and its variants are yet unclear. Here, we show that infection with SARS-CoV-2 activates AhR signaling and facilitates viral replication by interfering with IFN-I-driven antiviral immunity and up-regulating ACE2 receptor expression. The pharmacological AhR blockade or AhR knockout reduces SARS-CoV-2 and its variants' replication in vitro. Drug targeting of AhR with AhR antagonists markedly reduced SARS-CoV-2 and its variants' replication in vivo and ameliorated lung inflammation caused by SARS-CoV-2 infection in hamsters. Overall, AhR was a SARS-CoV-2 proviral host factor and a candidate host-directed broad-spectrum target for antiviral therapy against SARS-CoV-2 and its variants, including Delta and Omicron, and potentially other variants in the future.

Early peripheral blood MCEMP1 and HLA-DRA expression predicts COVID-19 prognosis

BACKGROUND

Mass vaccination has dramatically reduced the incidence of severe COVID-19, with most cases now presenting as self-limiting upper respiratory tract infections. However, those with co-morbidities, the elderly and immunocompromised, as well as the unvaccinated, remain disproportionately vulnerable to severe COVID-19 and its sequelae. Furthermore, as the effectiveness of vaccination wanes with time, immune escape SARS-CoV-2 variants could emerge to cause severe COVID-19. Reliable prognostic biomarkers for severe disease could be used as early indicator of re-emergence of severe COVID-19 as well as for triaging of patients for antiviral therapy.

METHODS

We performed a systematic review and re-analysis of 7 publicly available datasets, analysing a total of 140 severe and 181 mild COVID-19 patients, to determine the most consistent differentially regulated genes in peripheral blood of severe COVID-19 patients. In addition, we included an independent cohort where blood transcriptomics of COVID-19 patients were prospectively and longitudinally monitored previously, to track the time in which these gene expression changes occur before nadir of respiratory function. Single cell RNA-sequencing of peripheral blood mononuclear cells from publicly available datasets was then used to determine the immune cell subsets involved.

FINDINGS

The most consistent differentially regulated genes in peripheral blood of severe COVID-19 patients were MCEMP1, HLA-DRA and ETS1 across the 7 transcriptomics datasets. Moreover, we found significantly heightened MCEMP1 and reduced HLA-DRA expression as early as four days before the nadir of respiratory function, and the differential expression of MCEMP1 and HLA-DRA occurred predominantly in CD14+ cells. The online platform which we developed is publicly available at https://kuanrongchan-covid19-severity-app-t7l38g.streamlitapp.com/, for users to query gene expression differences between severe and mild COVID-19 patients in these datasets.

INTERPRETATION

Elevated MCEMP1 and reduced HLA-DRA gene expression in CD14+ cells during the early phase of disease are prognostic of severe COVID-19.

FUNDING

K.R.C is funded by the National Medical Research Council (NMRC) of Singapore under the Open Fund Individual Research Grant (MOH-000610). E.E.O. is funded by the NMRC Senior Clinician-Scientist Award (MOH-000135-00). J.G.H.L. is funded by the NMRC under the Clinician-Scientist Award (NMRC/CSAINV/013/2016-01). S.K. is funded by the NMRC under the Transition Award. This study was sponsored in part by a generous gift from The Hour Glass.

Antibody response to third and fourth BNT162b2 mRNA booster vaccinations in healthcare workers in Tokyo, Japan

BACKGROUND

Booster vaccinations against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are being promoted worldwide to counter the coronavirus disease 2019 (COVID-19) pandemic. In this study, we analyzed the longitudinal effect of the third BNT162b2 mRNA vaccination on antibody responses in healthcare workers. Additionally, antibody responses induced by the fourth vaccination were analyzed.

METHODS

The levels of anti-spike (S) IgG and neutralizing antibody against SARS-CoV-2 were measured at 7 months after the second vaccination (n = 1138), and at 4 (n = 701) and 7 (n = 417) months after the third vaccination using an iFlash 3000 chemiluminescence immunoassay analyzer. Among the 417 participants surveyed at 7 months after the third vaccination, 40 had received the fourth vaccination. A multiple linear regression analysis was performed to clarify which factors were associated with the anti-S IgG and neutralizing antibody. Variables assessed included sex, age, number of days after the second or third vaccination, diagnostic history of COVID-19, and anti-nucleocapsid (N) IgG level.

RESULTS

At 7 months after the third vaccination, antibody responses were significantly higher than those at the same time after the second vaccination. Unlike the second vaccination, age had no effect on the antibody responses induced by the third vaccination. Furthermore, the fourth vaccination resulted in a further increase in antibody responses. The multiple linear regression analysis identified anti-N IgG level, presumably associated with infection, as a factor associated with antibody responses.

CONCLUSIONS

Our findings showed that BNT162b2 booster vaccinations increased and sustained the antibody responses against SARS-CoV-2.

Recent Advances in ROS-Scavenging Metallic Nanozymes for Anti-Inflammatory Diseases: A Review

Oxidative stress and dysregulated inflammatory responses are the hallmarks of inflammatory disorders, which are key contributors to high mortality rates and impose a substantial economic burden on society. Reactive oxygen species (ROS) are vital signaling molecules that promote the development of inflammatory disorders. The existing mainstream therapeutic approaches, including steroid and non-steroidal anti-inflammatory drugs, and proinflammatory cytokine inhibitors with anti-leucocyte inhibitors, are not efficient at curing the adverse effects of severe inflammation. Moreover, they have serious side effects. Metallic nanozymes (MNZs) mimic the endogenous enzymatic process and are promising candidates for the treatment of ROS-associated inflammatory disorders. Owing to the existing level of development of these metallic nanozymes, they are efficient at scavenging excess ROS and can resolve the drawbacks of traditional therapies. This review summarizes the context of ROS during inflammation and provides an overview of recent advances in metallic nanozymes as therapeutic agents. Furthermore, the challenges associated with MNZs and an outline for future to promote the clinical translation of MNZs are discussed. Our review of this expanding multidisciplinary field will benefit the current research and clinical application of metallic-nanozyme-based ROS scavenging in inflammatory disease treatment.

Severe rhabdomyolysis secondary to COVID-19 mRNA vaccine in a teenager

BACKGROUND

Rhabdomyolysis, the breakdown of skeletal muscles following an insult or injury, has been established as a possible complication of SARS-CoV-2 infection. Despite being highly effective in preventing COVID-19-related morbidity and mortality, several cases of COVID-19 mRNA vaccination-induced rhabdomyolysis have been identified. We provide the second description of a pediatric case of severe rhabdomyolysis presenting after COVID-19 mRNA vaccination.

CASE

DIAGNOSIS/TREATMENT: A 16-year-old male reported to the emergency department with a 2-day history of bilateral upper extremity myalgias and dark urine 2 days after his first dose of COVID-19 vaccine (Pfizer-BioNtech). The initial blood work showed an elevated creatinine kinase (CK) of 141,300 units/L and a normal creatinine of 69 umol/L. The urinalysis was suggestive of myoglobinuria, with the microscopy revealing blood but no red blood cells. Rhabdomyolysis was diagnosed, and the patient was admitted for intravenous hydration, alkalinization of urine, and monitoring of kidney function. CK levels declined with supportive care, while his kidney function remained normal, and no electrolyte abnormalities developed. The patient was discharged 5 days after admission as his symptoms resolved.

CONCLUSION

While vaccination is the safest and most effective way to prevent morbidity from COVID-19, clinicians should be aware that rhabdomyolysis could be a rare but treatable adverse event of COVID-19 mRNA vaccination. With early recognition and diagnosis and supportive management, rhabdomyolysis has an excellent prognosis.