Worldwide perspectives on venom allergy

Comparative study of the commonly used protein quantitation assays on different Hymenoptera venoms: A fundamental aspect of Hymenoptera venom proteome analysis

Determination of protein concentration in Hymenoptera venoms requires an accurate and reproducible assay as the results will be used to support subsequent proteomic techniques employed in their analyses. However, all protein assay techniques have inherent strengths and weaknesses, demanding their assessment before selecting the most suitable platform for sample analysis. In this study, protein profiles of ant, honeybee, and wasp venoms, and bovine serum albumin (BSA) and hyaluronidase standards were qualitatively assessed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Their amino acid and protein concentration were quantitatively determined via Amino Acid Analysis (AAA). Amino acid concentration was determined via hydrolysis, derivatization, and chromatographic quantification. Protein concentration was estimated using four different protein concentration assays. The ratios of protein concentration in venom samples to protein standards were calculated, and the accuracy of the protein concentration assays was analysed relative to the concentration determined from AAA. SDS-PAGE analysis showed that BSA contained several protein bands, while hyaluronidase contained a mixture of peptide and protein bands. Ant and honeybee venoms contained a higher proportion of peptide bands, while wasp venom contained more protein bands. As determined by AAA, the ratio of protein concentration in Hymenoptera venoms varied between 1.01 and 1.11 to BSA, and between 0.96 and 1.06 to hyaluronidase. Overall, the Bradford assay was found to be the least accurate and the BCA assay was the most accurate in estimating protein concentration in Hymenoptera venoms. There was no significant advantage in using hyaluronidase as a standard or increasing incubation temperature of BCA assay when analysing Hymenoptera venoms. Diluent solutions containing phenol and human serum albumin interfered with Lowry-based assays.

Revamped mini-αA-crystallin showed improved skin permeation and therapeutic activity against melittin-induced toxicity

Melittin is honey bee venom's primary and most toxic pharmacologically active component. Melittin causes haemolysis, lymphocyte lysis, long-term pain, localised inflammation followed by rhabdomyolysis, and severe renal failure. Renal failure or cardiovascular complications could lead to the victim's death. Severe honey bee bites are treated with general medication involving antihistaminic, anti-inflammatory, and analgesic drugs, as a specific treatment option is unavailable. An earlier study showed the anti-hemolysis and anti-lymphocyte lysis activity of mini- αA-crystallin (MAC), a peptide derived from human eye lens alpha-crystallin. MAC's use has often been restricted despite its high therapeutic potential due to its poor skin permeability. This study compared the skin permeation, anti-inflammatory and analgesic activities of natural peptide MAC and its modified version (MAC-GRD) formed by attaching cell-penetrating peptide (CPP) and GRD amino residues into MAC. Gel formulations were prepared for MAC and MAC-GRD peptides using carbopol (1% w/w), Tween 80 (1%), and ethanol (10%). An ex-vivo skin permeation study was performed using a vertical-type Franz diffusion apparatus. Preclinical in-vivo experiments were conducted to compare the native and modified peptide formulations against melittin-induced toxicity in Wistar rats. MAC gel, MAC-GRD gel and 1% hydrocortisone cream significantly reduced the melittin-induced writhing (20.16 ± 0.792) response in rats with 15.16 ± 0.47, 11.16 ± 0.477 and 12.66 ± 0.66 wriths, respectively. There was a significant reduction in melittin-induced inflammation when MAC-GRD gel was applied immediately after melittin administration. At 0.5, 1, 3, and 5 h, the MAC-GRD-treated rat paws were 0.9 ± 0.043 mm, 0.750 ± 0.037 mm, 0.167 ± 0.0070 mm, and 0.133 ± 0.031 mm thick. Administration of melittin resulted in reduced GSH (antioxidant) levels (47.33 ± 0.760 μg/mg). However, treatment with MAC-GRD gel (71.167 ± 0.601 μg/mg), MAC gel (65.167 ± 1.138 μg/mg), and 1% hydrocortisone (68.33 ± 0.667 μg/mg) significantly increased the antioxidant enzyme levels. MAC-GRD gel significantly reduced the elevated MDA levels (6.933 ± 0.049 nmol/mg) compared to the melittin group (12.533 ± 0.126 nmol/mg), followed by the 1% hydrocortisone (7.367 ± 0.049 nmol/mg) and MAC gel (7.917 ± 0.048 nmol/mg). MAC-GRD demonstrated more skin permeability and superior anti-inflammatory, analgesic, and antioxidant activities when compared to MAC gel. When compared to standard 1% hydrocortisone cream, MAC-GRD had better anti-inflammatory, analgesic, antioxidant, and comparable action in anti-oxidant restoration against melittin. These findings suggest that the developed MAC-GRD gel formulation could help to treat severe cases of honey bee stings.

Updates and Recent Advances on Venom Immunotherapy

Purpose of Review

Venom immunotherapy has been utilized to treat Hymenoptera venom allergy since the 1920s. Over the last century, significant advances in the fields of immunology and genetics have led to improvements in the practice of venom immunotherapy. This review encompasses recent advances in the use of venom immunotherapy to provide precise, patient-centered care.

Recent Findings

Research about the mechanism of action of venom immunotherapy continues to highlight the modification of both the innate and adaptive immune systems. Molecular techniques have allowed for the identification of specific venom allergens to improve the diagnostic accuracy and safety of venom immunotherapy. Research continues to support the safety of accelerated schedules which can impact the cost, adherence, and quality of life for patients receiving this treatment modality. Finally, significant advances have led to the elucidation of risk factors that place patients at risk for reactions during and after venom immunotherapy. Creation of risk profiles for venom-allergic patients can thus inform the process of immunotherapy in order to provide personalized and precise care.

Summary

Significant progress in the use of venom immunotherapy makes the practice a dynamic and active field for continued research. Future research needs to build on these recent advances to continue to optimize and enhance this life-saving treatment.

Disparities in the Diagnosis and Management of Anaphylaxis

PURPOSE OF REVIEW

The goal of this review is to characterize health disparities impacting the recognition and treatment of anaphylaxis.

RECENT FINDINGS

Previous research has identified major health disparities related to atopic conditions including asthma, atopic dermatitis, and food allergies (FA); however, disparities related to anaphylaxis have yet to be examined in depth. We found widespread health disparities in the incidence and severity of anaphylaxis, as well as in the management of allergies (particularly food allergies) that place individuals at risk of anaphylaxis. Sociodemographic factors are associated with numerous negative health outcomes related to anaphylaxis. We highlight several key steps that must be taken to address these disparities.

Diagnosis and Management of Insect Allergy: Barriers and Facilitators in the United States

While guidelines recommend testing and treatment for patients with venom-induced anaphylaxis to prevent morbidity and mortality, significant barriers prevent most patients from receiving the evaluation and treatments that they need. This review examines these barriers in the United States along with the facilitators that can be used to overcome them.

Allergen Immunotherapy Extract Shortages and Their Effects on Clinical Care: A Work Group Report of the AAAAI Immunotherapy, Allergen Standardization, and Allergy Diagnostics Committee

Allergen immunotherapy (AIT) is the only disease-modifying therapy indicated for treatment of allergic asthma, rhinitis, conjunctivitis, and Hymenoptera hypersensitivity. Manufacturing of the extracts used in AIT involve multistep complex processes as well as regulatory oversight. Furthermore, some source materials are vulnerable to unexpected events of nature. Given these circumstances, allergen extract supply can be disrupted with a potential to adversely impact patient care. A group of members from the American Academy of Allergy, Asthma, and Immunology (AAAAI) Immunotherapy, Allergy Standardization and Allergy Diagnostic Committee formed a workgroup to assess the frequency and effects of allergen extract shortages and associated factors. This workgroup developed a survey that was distributed to a random 20% of the AAAAI membership. In addition, the group also performed a review of the scientific literature on allergen extract supply and shortage. Based on the findings of the survey study and literature review, the workgroup reports frequency and extent of shortages, potential ways to improve communication with suppliers, and need for further guidance in patient care during times of shortage.

Wilderness Medical Society Clinical Practice Guidelines on Anaphylaxis

The Wilderness Medical Society convened a panel to review the literature and develop evidence-based clinical practice guidelines on the treatment of anaphylaxis, with an emphasis on a field-based perspective. The review also included literature regarding the definition, epidemiology, clinical manifestations, and prevention of anaphylaxis. The increasing prevalence of food allergies in the United States raises concern for a corresponding rise in the incidence of anaphylaxis. Intramuscular epinephrine is the primary treatment for anaphylaxis and should be administered before adjunctive treatments such as antihistamines, corticosteroids, and inhaled β agonists. For outdoor schools and organizations, selecting a method to administer epinephrine in the field is based on considerations of cost, safety, and first responder training, as well as federal guidelines and state-specific laws.

Asian Hornet, Vespa velutina Lepeletier 1836 (Hym.: Vespidae), Venom Obtention Based on an Electric Stimulation Protocol

The yellow-legged Asian hornet (Vespa velutina Lepeletier 1836 (Hymenoptera: Vespidae)) is naturally distributed in China, Southeast Asia, and India; however, recently it has been detected outside of its native area, confirmed as being established in South Korea, Europe, and Japan. Health risks and deaths caused by the invasive Vespa velutina stings have become a public health concern, being the most common cause of anaphylaxis due to hymenopterans in some European regions. This in turn has led to increased demand from medical practitioners and researchers for Vespa velutina venom for diagnostic and therapeutic purposes. In this study, a straightforward, quick, and inexpensive method for obtaining Vespa velutina venom by electric stimulation is described. The venom extracts were analyzed by nuclear magnetic resonance spectroscopy (¹H-NMR). The availability of Vespa velutina venom will lead to improved diagnostic and therapeutic methods, mainly by venom immunotherapy (VIT), in patients allergic to this invasive species.

The role of component-resolved diagnosis in Hymenoptera venom allergy in clinical practice

Background: Hymenoptera venom allergy is an immunoglobulin (Ig) E mediated hypersensitivity reaction to Hymenoptera venoms. Obvious identification of the culprit insect that causes the clinical symptoms and, hence, the accurate selection of venom for curative treatment, is of great importance for the effectiveness and safety of venom immunotherapy. Objective: In this study, the contribution of component-resolved diagnostics (CRD) is evaluated in the diagnosis of Hymenoptera venom allergy. Method: Ninety-three patients from four different centers in Turkey were included in the study. Conventional tests, including prick and intradermal skin tests, with commercial venom extracts and serum specific IgE (sIgE) levels for whole venoms were performed. An sIgE analysis for venom allergen components, including rApi m 1, rApi m 2, rApi m 10, rVes v 1, rVes v 5, were evaluated by immunoblotting. Results: In conventional test results, 17 of 35 patients with bee venom allergy were positive to honey bee venom, whereas 18 patients were positive to bee and wasp venoms. In 28 of 35 patients with bee venom allergy, the diagnosis was confirmed with CRD. CRD revealed a sensitivity of 80% in patients with bee venom allergy. According to conventional tests, 7 of 24 patients with vespid venom allergy demonstrated sensitivity only to Vespula species, whereas 17 patients revealed double positivity. The total diagnostic sensitivity of Ves v 1 and Ves v 5 was calculated as 87.5%. Ten of 23 patients with a history of hypersensitivity to both venoms showed double sensitivity with CRD; one patient had cross-reactivity, one patient was found to be sensitive only to bee venom, and, eight patients were sensitive only to Vespula species. Eleven patients had an uncertain history in terms of the culprit insect type and six of them had double sensitivity in CRD. Conclusion: CRD seemed to be more helpful in diagnosing vespid venom allergy than bee venom allergy. It can also discriminate clinically significant sensitizations from irrelevant ones.

Past, present, and future of allergen immunotherapy vaccines

Allergen-specific immunotherapy (AIT) is an allergen-specific form of treatment for patients suffering from immunoglobulin E (IgE)-associated allergy; the most common and important immunologically mediated hypersensitivity disease. AIT is based on the administration of the disease-causing allergen with the goal to induce a protective immunity consisting of allergen-specific blocking IgG antibodies and alterations of the cellular immune response so that the patient can tolerate allergen contact. Major advantages of AIT over all other existing treatments for allergy are that AIT induces a long-lasting protection and prevents the progression of disease to severe manifestations. AIT is cost effective because it uses the patient´s own immune system for protection and potentially can be used as a preventive treatment. However, broad application of AIT is limited by mainly technical issues such as the quality of allergen preparations and the risk of inducing side effects which results in extremely cumbersome treatment schedules reducing patient´s compliance. In this article we review progress in AIT made from its beginning and provide an overview of the state of the art, the needs for further development, and possible technical solutions available through molecular allergology. Finally, we consider visions for AIT development towards prophylactic application.

Tabanidae insect (horsefly and deerfly) allergy in humans: A review of the literature

Allergy to insects of the family Tabanidae (order Diptera), commonly called horseflies or deerflies, is anecdotally common, although the published literature is limited to case reports and small case series. This review summarizes the available literature, in which there is enormous variability in clinical detail, identification of species or even genus, and means and thoroughness of assessment of sensitization. The clinical utility of in vivo and in vitro assays remains unclear. Investigation and management of patients reporting anaphylaxis to suspected bites must therefore be pragmatic, by considering other insects (eg Hymenoptera), provision of a written action plan and self-injectable adrenaline if appropriate, and advice on avoidance.