Leveraging an mRNA Platform for the Development of Vaccines Against Egg Allergy.

Background: Food allergy (FA) poses a major global health issue due to the increasing prevalence and lack of effective prevention strategies. Allergen-specific immunotherapy (AIT) has emerged as a disease-modifying therapy for FA. However, due to long-term treatment duration and unexpected adverse reactions, only a minority of patients benefit from AIT. Therefore, effective prophylactic interventions are urgently needed for FA patients. Methods: In this proof-of-concept study, using a well-established mRNA platform, we developed mRNA vaccine candidates encoding for the major egg white allergen Gal d2 and comprehensively evaluated their prophylactic efficacy against anaphylaxis in a Gal d2-induced allergic mouse model. Results: Two vaccine formulations, Gal d2 mRNA vaccine and Gal d2-IL-10 mRNA vaccine, both demonstrated potent ability in inducing allergen-specific IgG and Th1-type T cells. Importantly, the two vaccine formulations showed promise in preventing the onset of allergic disease, which is indicated by prevention of body temperature decline during anaphylaxis. Conclusions: We provided preliminary proof-of-concept evidence showing that the mRNA platform is unique and holds promise for the development of anti-allergy vaccines. This is largely attributed to the capacities of mRNA vaccines in eliciting an allergen-blocking antibody, shifting Th2 towards Th1 immunity, as well as in generating peripheral tolerance. However, further investigations are required to better understand the mode of action.