Hypersensitivity reactions to anti-SARS-CoV-2 vaccines: Basophil reactivity to excipients

Can Labs Help With Vaccination? In Vitro Tests in Diagnosis of Allergy to COVID-19 Vaccines-A Systematic Review

INTRODUCTION

Since the outbreak of the coronavirus pandemic in 2019, vaccinations have proven to be a key strategy in disease prophylaxis. Although vaccines are safe from the perspective of the general population, hypersensitivity reactions have still been described, causing individuals to be reluctant in their vaccination decision. Since the description of first reports of COVID-19 vaccine allergy, many protocols of allergy work-up have been developed, including In Vitro and In Vivo tests. Although In Vivo tests were more accessible, many patients preferred In Vitro tests that would not involve contact with the allergen and be safe. This applied in particular to patients that had experienced a severe delayed hypersensitivity reaction in which In Vivo tests were highly limited and provocations were deemed high risk. Taking into account these circumstances, In Vitro tests might significantly enhance allergy work-up.

METHODS

National Center for Biotechnology Information (Pubmed) database was searched in May 2024 for articles on In Vitro diagnostic methods for COVID-19 vaccine allergy and hypersensitivity.

RESULTS

This article describes the In Vitro tests developed to date in the diagnosis of COVID-19 vaccine hypersensitivity: (1) analysis of specific IgE and IgG, (2) Basophil Activation Test, (3) Histamine Release Test, (4) IgM-dependent complement activation, (5) Lymphocyte Transformation Test, (6) Flow cytometry T-Cell markers, (7) Th1/Th2 cytokines concentration in cell culture.

CONCLUSIONS

The article highlights the tests' advantages, flaws and possible clinical applications.

The role of leukocyte activation in suspected Non-IgE excipient-related COVID-19 vaccine reactions: An exploratory hypothesis-driven study of pathogenesis

Background: Adverse allergic reactions due to the administration of vaccines developed for the protection of coronavirus disease 2019 (COVID-19) have been reported since the initiation of the vaccination campaigns in December 15, 2020. Current analyses provided by the Centers for Disease Control and Prevention and the U.S. Food and Drug Administration in the United States have estimated the rates of anaphylactic reactions in 2.5 and 11.1 per million of messenger RNA (mRNA) 1273 and BNT162b2 vaccines administered, respectively. The mechanisms by which these mRNA vaccines induce adverse vaccine reactions have been the subject of conflicting reports. Although skin testing with excipient components found in mRNA-1273 and BNT162b2 vaccines, such as polyethylene glycol (PEG) and related vaccine lipid products, were originally recommended to identify potential predictive biomarkers of adverse allergic reactions, more recent evidence has suggested that routine skin testing with these vaccine excipients have poor predictability and do not correlate with susceptibility to vaccine injury. Objective: The goal of this proof-of-concept (POC) exploratory study was to investigate the role of leukocyte activation (LA) induced by lipid excipients found in mRNA COVID-19 vaccines in the pathogenesis of COVID-19 mRNA vaccine-associated adverse reactions by using an LA assay developed in our laboratory. Results: An LA assay was performed on blood samples obtained from 30 study subjects who were assigned to three study groups: group 1 consisted of 10 subjects who had received an mRNA COVID-19 vaccine and developed a serious vaccine adverse reaction; group 2 consisted of 10 subjects who had received a COVID-19 vaccine and developed a mild adverse reaction; and group 3 consisted of 10 subjects who had not received a COVID-19 vaccine and were asymptomatic. Five excipients were tested in each of the 10 subjects; hence, a potential of 50 reactions could be expressed in each of the three groups. In the subjects in group 1 who had shown clinically severe vaccine effects, 8 of 50 (16%) had severe LA index (LAI) responses (>144.83), 12 of 50 (24%) had moderate LAI responses (87.62 -144.82), and 30 of 50 (60%) had no reaction (0 - 87.61). In the subjects in group 2 who had shown clinically mild vaccine effects, 4 of 50 (8%) had severe LAI responses (>144.83), 9 of 50 (18%) had moderate LAI responses (87.62 -144.82), and 37 of 50 (74%) had no reaction. In the subjects in group 3 who had not received the vaccine and, therefore, had no clinical vaccine effects, 2 of 50 (4%) had severe LAI responses (>144.83), 10 of 50 (20%) had moderate LAI responses (87.62 -144.82), and 38 of 50 (76%) had no reaction LA index (LAI) responses. Conclusion: The results of this exploratory POC study suggest that the measurement of LA induced by PEG and other vaccine-related lipid excipients found in mRNA COVID-19 vaccines may provide a novel and useful predictive biomarker associated with adverse non-immunoglobulin E (IgE) related allergic reactions to these vaccines. The study results also underscore growing concerns related to these non-IgE hypersensitivity reactions and their potential for pathogenesis of adverse vaccine reactions. This is particularly noteworthy because, with the continuing emergence of novel and evolving variants of severe acute respiratory syndrome corona-virus 2 mutants, yearly immunization with mRNA vaccines will most likely be recommended. Although the study was not sufficiently powered to draw definitive conclusions with regard to associations between vaccine-associated COVID-19 reactions and LA, the trends of a more severe set of clinical reactions seen associated with LAI reactivity scores, particularly with ALC-0159 (2-[{polyethylene glycol} 2000]-N,N-ditetradecylacetamide), suggest a potential benefit worthy of exploration in future randomized controlled trials.

Chronic urticaria: not only after COVID-19 vaccination

PURPOSE OF REVIEW

To resume the current literature about vaccination and the onset of chronic urticaria.

RECENT FINDINGS

The recent large-scale vaccination against SARS-CoV-2 targeting elderly, adult and children, has highlighted how vaccines can trigger onset or exacerbation of chronic urticaria.

SUMMARY

COVID-19 vaccines may act as triggers in the development of chronic spontaneous urticaria. More data regarding the other vaccines are necessary to evaluate a similar potential role. Proper education of patients with vaccine-induced chronic urticaria is essential to avoid vaccination hesitancy.

Right Biceps Pseudo-Tumor from COVID-19 Vaccination

Delayed hypersensitivity reactions (DHRs) have been reported in association with COVID-19 vaccines, particularly those that are mRNA-based. Classic DHRs result in induration, erythema, tenderness, and urticaria. However, soft tissue mass is an uncommon complication of a COVID-19 vaccination-associated DHR and is rarely reported in the literature. We present a case of a 49-year-old male who recognized a mildly painful, firm soft tissue mass within the biceps mimicking neoplasm six months after receiving the booster dose of the Moderna vaccine. Non-operative conservative treatment modalities, including heating pads, ice packs, acetaminophen, and ibuprofen, failed to improve the patient's mass. The mass, which proved histologically to be an inflammatory pseudo-tumor, did not recur after complete excision. While there have been many reported cases of DHRs following COVID-19 vaccinations, we present this case to raise awareness of the development of pseudo-tumors as a possible, yet rare, clinical manifestation of DHRs following vaccination.

Real-Life Utility of Basophil Activation Test in the Diagnosis of Immediate Hypersensitivity Drug Reactions

INTRODUCTION

The basophil activation test (BAT) is a flow cytometry laboratory technique that assesses the level of activation indicators expressed on the surface of basophils. We conducted a real-life study in a prospective cohort of patients with reported drug hypersensitivity reactions to determine the true relevance of BAT as a diagnostic tool for assessing immediate hypersensitivity reactions to medicines.

METHODS

We prospectively assessed individuals with clinical suspicion of immediate hypersensitivity reactions to drugs over a 2-year period. The allergological evaluation was carried out in accordance with European Academy of Allergy and Clinical Immunology (EAACI) guidance. All patients underwent BAT using the activation marker CD63.

RESULTS

In total 13 patients with 54 reported immediate drug hypersensitivity reactions to medications were included in this study. Twelve were female (92.3%) and one was male (7.70%). The mean ± SD age of the patients was 47.31 ± 19.94 years. Antibiotics were tested in 35.2% (19/54) of patients, corticosteroids in 24.1% (13/54), iodinated contrast medium in 14.8% (8/54), and NSAIDs in 5.6% (3/54). There was no correlation between the BAT results and the age of patients, gender, type of medication, or time interval between the allergic reaction and BAT procedure. The sensitivity of BAT 5% CD63+ basophils to drugs was 97.6%, specificity was 96% for drug allergies, positive predictive value (PPV) was 94.3%, and negative predictive value (NPV) was 95.2%.

CONCLUSIONS

The sensitivity of BAT for drug allergies is limited, but it can nevertheless be very helpful before contemplating provocation testing in cases of life-threatening drug allergies where patients cannot be rechallenged or in cases of medications for which no other tests are available or their results are ambiguous.