Formulations for Allergen Immunotherapy in Human and Veterinary Patients: New Candidates on the Horizon

Abstract

Allergen immunotherapy is currently the only causal treatment for allergic diseases in human beings and animals. It aims to redirect the immune system into a tolerogenic or desensitized state. Requirements include clinical efficacy, safety, and schedules optimizing patient or owner compliance. To achieve these goals, specific allergens can be formulated with adjuvants that prolong tissue deposition and support uptake by antigen presenting cells, and/or provide a beneficial immunomodulatory action. Here, we depict adjuvant formulations being investigated for human and veterinary allergen immunotherapy.

Allergens and Adjuvants in Allergen Immunotherapy for Immune Activation, Tolerance, and Resilience

“…The purpose of adjuvants in AIT is to skew the robust T H 2 immune bias toward the cytosolic inflammatory pathway for enhanced antigen cross-presentation and IgG production (Figure 1, B), or toward the vacuolar pathway with a clear T H 1 shift and active tolerance (Figure 1, C). Adjuvants in AIT products in the European market, in human and veterinary applications, 16 mechanistically combine these strategies. 5 Immunoactivatory adjuvants such as alum, calcium phosphate, or microcrystalline tyrosin (Figure 1, B) all form crystals that physically equip the allergen with strong danger signals (exception: specific chemical modifications; for instance, exchange of hydroxyl ions in alum with phosphate groups inhibits the crystallization process, resulting in an amorphous state of aggregation).…”

One Health in allergology: A concept that connects humans, animals, plants, and the environment

“…3 One Health thus is a timely concept in terms of the current COVID-19 pandemic, considering the interspecies viral transmission A One Health approach is needed in allergolgy, as allergic diseases are found in human and non-human mammals alike, [5][6][7] , the prevalence of some of them still on the rise, and the diagnosis and treatment comparable in many cases. 8,9 For all mammalian species affected by allergies, a plethora of common factors seems to be responsible for disease development, duration, and severity (Figure 1). Effects of the global warming, climate change, and air pollution have already become clear, 10 among them, we find novel species of plants (eg, ragweed) and animals (eg, insects like Polistes spp.)…”

“…A One Health approach is needed in allergolgy, as allergic diseases are found in human and non‐human mammals alike, 5‐7 , the prevalence of some of them still on the rise, and the diagnosis and treatment comparable in many cases 8,9 . For all mammalian species affected by allergies, a plethora of common factors seems to be responsible for disease development, duration, and severity (Figure 1).…”