ABSTRACT
Less than a year after the global emergence of the coronavirus SARS-CoV-2, a novel vaccine platform based on mRNA technology was introduced to the market. Globally, around 13.38 billion COVID-19 vaccine doses of diverse platforms have been administered. To date, 72.3% of the total population has been injected at least once with a COVID-19 vaccine. As the immunity provided by these vaccines rapidly wanes, their ability to prevent hospitalization and severe disease in individuals with comorbidities has recently been questioned, and increasing evidence has shown that, as with many other vaccines, they do not produce sterilizing immunity, allowing people to suffer frequent re-infections. Additionally, recent investigations have found abnormally high levels of IgG4 in people who were administered two or more injections of the mRNA vaccines. HIV, Malaria, and Pertussis vaccines have also been reported to induce higher-than-normal IgG4 synthesis. Overall, there are three critical factors determining the class switch to IgG4 antibodies: excessive antigen concentration, repeated vaccination, and the type of vaccine used. It has been suggested that an increase in IgG4 levels could have a protecting role by preventing immune over-activation, similar to that occurring during successful allergen-specific immunotherapy by inhibiting IgE-induced effects. However, emerging evidence suggests that the reported increase in IgG4 levels detected after repeated vaccination with the mRNA vaccines may not be a protective mechanism; rather, it constitutes an immune tolerance mechanism to the spike protein that could promote unopposed SARS-CoV2 infection and replication by suppressing natural antiviral responses. Increased IgG4 synthesis due to repeated mRNA vaccination with high antigen concentrations may also cause autoimmune diseases, and promote cancer growth and autoimmune myocarditis in susceptible individuals.
ABSTRACT
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been challenging the scientific community to promptly treat the patients and mitigate its spreading. The rapid development of vaccination against SARS-CoV-2 is being highly effective, but it is still lacking knowledge about its side effects. Epidemiological studies point toward virus infection as causative agents of subacute thyroiditis. More than 20 cases of thyroiditis after SARS-CoV-2 have also been described. Here, we aim to broad the spectrum of SARS-CoV-2 vaccination thyroid-associated disorders with the description of a new case of subacute thyroiditis associated with thyroid autoimmunity. The temporal association with the inoculation of the vaccine and the absence of other plausible etiological agents makes it highly possible that this thyroiditis was caused by Vaxzevria vaccine. It remains to be established whether the presence of thyroid autoimmunity can facilitate this condition, as this is one of the few described cases associated with autoimmunity.
ABSTRACT
For the foreseeable future, vaccines are the cornerstone in the global campaign against the Coronavirus Disease-19 (COVID-19) pandemic. As the number and fatalities due to COVID-19 decline and the lockdown anywise rescinded, we recognize an increase in the incidence of autoimmune disease post-COVID-19 vaccination. However, the causality of the most vaccine-induced side effects is debatable and, at best, limited to a temporal correlation. We herein report a case of a 51-year-old gentleman who developed Anti-Neutrophil Cytoplasmic Antibody (ANCA)-associated vasculitis (AAV) 2 week post-COVID-19 vaccination. The patient responded favorably to oral steroids and rituximab. Additionally, we conducted a case-based review of vaccine-associated AAV describing their clinical manifestations and treatment response of this emerging entity.
Subject(s)
Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis , COVID-19 , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/drug therapy , Antibodies, Antineutrophil Cytoplasmic , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Communicable Disease Control , Humans , Male , Middle Aged , VaccinationABSTRACT
The article describes the rationale for the administration of zinc-chelating agents in COVID-19 patients. In a previous work I have highlighted that the binding of the SARS-CoV spike proteins to the zinc-metalloprotease ACE2 has been shown to induce ACE2 shedding by activating the zinc-metalloprotease ADAM17, which ultimately leads to systemic upregulation of ACE2 activity. Moreover, based on experimental models, it was also shown the detrimental effect of the excessive systemic activity of ACE2 through its downstream pathways, which leads to "clinical" manifestations resembling COVID-19. In this regard, strong upregulation of circulating ACE2 activity was recently reported in COVID-19 patients, thus supporting the previous hypothesis that COVID-19 may derive from upregulation of ACE2 activity. Based on this, a reasonable hypothesis of using inhibitors that curb the upregulation of both ACE2 and ADAM17 zinc-metalloprotease activities and consequent positive feedback-loops (initially triggered by SARS-CoV-2 and subsequently sustained independently on viral trigger) is proposed as therapy for COVID-19. In particular, zinc-chelating agents such as citrate and ethylenediaminetetraacetic acid (EDTA) alone or in combination are expected to act in protecting from COVID-19 at different levels thanks to their both anticoagulant properties and inhibitory activity on zinc-metalloproteases. Several arguments are presented in support of this hypothesis and based on the current knowledge of both beneficial/harmful effects and cost/effectiveness, the use of chelating agents in the prevention and therapy of COVID-19 is proposed. In this regard, clinical trials (currently absent) employing citrate/EDTA in COVID-19 are urgently needed in order to shed more light on the efficacy of zinc chelators against SARS-CoV-2 infection in vivo.