Is vaccination against IgE possible?

Allergic Reactions to Current Available COVID-19 Vaccinations: Pathophysiology, Causality, and Therapeutic Considerations

Vaccines constitute the most effective medications in public health as they control and prevent the spread of infectious diseases and reduce mortality. Similar to other medications, allergic reactions can occur during vaccination. While most reactions are neither frequent nor serious, anaphylactic reactions are potentially life-threatening allergic reactions that are encountered rarely, but can cause serious complications. The allergic responses caused by vaccines can stem from activation of mast cells via Fcε receptor-1 type I reaction, mediated by the interaction between immunoglobulin E (IgE) antibodies against a particular vaccine, and occur within minutes or up to four hours. The type IV allergic reactions initiate 48 h after vaccination and demonstrate their peak between 72 and 96 h. Non-IgE-mediated mast cell degranulation via activation of the complement system and via activation of the Mas-related G protein-coupled receptor X2 can also induce allergic reactions. Reactions are more often caused by inert substances, called excipients, which are added to vaccines to improve stability and absorption, increase solubility, influence palatability, or create a distinctive appearance, and not by the active vaccine itself. Polyethylene glycol, also known as macrogol, in the currently available Pfizer-BioNTech and Moderna COVID-19 mRNA vaccines, and polysorbate 80, also known as Tween 80, in AstraZeneca and Johnson & Johnson COVID-19 vaccines, are excipients mostly incriminated for allergic reactions. This review will summarize the current state of knowledge of immediate and delayed allergic reactions in the currently available vaccines against COVID-19, together with the general and specific therapeutic considerations. These considerations include: The incidence of allergic reactions and deaths under investigation with the available vaccines, application of vaccination in patients with mast cell disease, patients who developed an allergy during the first dose, vasovagal symptoms masquerading as allergic reactions, the COVID-19 vaccination in pregnancy, deaths associated with COVID-19 vaccination, and questions arising in managing of this current ordeal. Careful vaccine-safety surveillance over time, in conjunction with the elucidation of mechanisms of adverse events across different COVID-19 vaccine platforms, will contribute to the development of a safe vaccine strategy. Allergists’ expertise in proper diagnosis and treatment of allergic reactions is vital for the screening of high-risk individuals.

Novel IgE peptide-based vaccine prevents the increase of IgE and down-regulates elevated IgE in rodents

BACKGROUND

Immunotherapy with anti-IgE antibodies for treatment of allergy is promising but a short half-life and extremely high cost limit its application.

OBJECTIVE

We sought to develop IgE vaccines that induce longer-lasting auto-antibodies to neutralize self-IgE as an alternative therapy.

METHODS

The vaccine was made by conjugating three synthetic peptides corresponding to human IgE receptor-binding sites to a carrier, hepatitis B surface antigen. To test the immunogenicity of the vaccine, rats were immunized with the vaccine or hepatitis B surface antigen as control. Serum IgG titres to human IgE and the IgE of other species were measured. The inhibition by rat antisera of the binding of human IgE to its receptor was assessed by ELISA, flow cytometry analysis, and passive cutaneous anaphylaxis (PCA), and its ability to recognize receptor-bound IgE was examined. The in vivo effect of the vaccine was evaluated in trichosanthin-sensitized mice and rats. In the preventative study, vaccination started before sensitization commenced, while in the treatment study, vaccination started after sensitization. Sensitized mice and rats receiving injections of the carrier served as controls. Trichosanthin-specific IgE was measured using PCA.

RESULTS

Sera from vaccine-immunized rats contained high titre antibodies that reacted with soluble and plate-bound but not with receptor-bound human IgE; they also reacted with mouse, rat, and dog IgE. Furthermore, the sera inhibited the binding of human IgE to its receptor in a dose-dependent manner. In preventative and treatment studies, serum trichosanthin-specific IgE levels were significantly reduced in vaccinated groups compared with controls.

CONCLUSION

Antibodies against self-IgE can be induced by IgE peptide-based vaccines, which are effective in preventing the increase of IgE and in down-regulating IgE in sensitized animals.

Generation of therapeutic antibody responses against IgE through vaccination

IgE is the central mediator in atopic allergies such as hay fever, eczema, and asthma; therefore, it is a prime target in the development of allergen-independent preventive treatments. We describe an active immunization strategy that has the potential to reduce IgE to a clinically significant extent. The active vaccine component is a chimeric IgE molecule, Cepsilon2-Cepsilon3-Cepsilon4. The receptor-binding target domain, Cepsilon3, is derived from the recipient species, whereas the flanking domains, Cepsilon2 and Cepsilon4, are derived from an evolutionarily distant mammal. The flanking domains have dual functions, acting both as structural support for the Cepsilon3 domain and to break T cell tolerance by providing foreign T cell epitopes. The efficacy of the vaccine was studied in an ovalbumin-sensitized rat model. Vaccination resulted in antibody responses against IgE in all rats and in a substantial reduction in serum IgE levels in three out of four strains. The skin reactivity upon allergen challenge was significantly reduced in vaccinated animals. The vaccine appears to be safe to use as an antigen. No cross-linking activity was observed in sera of vaccinated animals, and the response to vaccination was reversible with time. Our results suggest that active immunization against IgE has the potential to become a therapeutic method for humans.

New treatments and the future role of immunotherapy: anti-IgE

OBJECTIVE

The review outlines an overview of anti-IgE, along with a description of the production and mechanism of action of the finished molecule. The immunologic effect of the drug and the drug complexes are detailed, and proof of efficacy is offered. The review also speculates about the role of anti-IgE in clinical use, along with potential future therapies, including gene substitution and genetic alteration.

DATA SOURCES

The author reviewed literature studying IgE and anti-IgE antibody.

STUDY SELECTION

The expert opinion of the author was used to select relevant data.

RESULTS

The injection of anti-IgE results in four proven reactions: free antibody is bound; not bound antibody is not dislodged to any degree; plasma B cell production of IgE drops; and high-affinity Fc epsilon RI and low-affinity Fc epsilon RII on mast cells and basophils are downregulated.

CONCLUSIONS

Based on observation of clinical reaction, anti-IgE is truly immunotherapy. Current opinion among clinical investigators about the impact of the impending approval of this new drug is that it will not replace standard immunotherapy. How it will fit into the armamentarium of physicians dealing with allergic disease, and protocols for its use, are still being debated.