Published online: March 22, 2017
Anaphylaxis is a potentially life-threatening, rapidly-progressing IgE-mediated systemic allergic reaction that may lead to death due to airway obstruction or vascular collapse following exposure to allergens including foods (peanuts, tree nuts, fish, and shellfish), insect venom, and medication. Its potential to occur can be of great concern for patients and clinicians. Exposure to these allergens leads to activation of the IgE receptor on mast cells or basophils, however, there is little published data demonstrating a direct contribution of basophils to human anaphylaxis.
In the article recently published in The Journal of Allergy & Clinical Immunology (JACI), Korosec and colleagues looked at the basophils in patients presenting with anaphylaxis to the emergency department (predominantly to insect venom) and in peanut-allergic individuals undergoing double-blind placebo-controlled food challenge to peanut.
The authors found a substantial (~80%) and rapid reduction in circulating basophils during anaphylaxis. Decreased gene expression of IgE receptor and other basophil related genes confirmed the flow cytometry cellular data. The basophil migration inversely correlates with increase in a major basophil chemotactic factor. The authors replicated these findings in peanut-allergic individuals experiencing allergic reactions during challenge to peanut. Compared to the reactions in the emergency department, which were generally more severe, they observed more modest (but nonetheless significant) changes at the time of objective symptoms during the peanut challenges. The mechanism of anaphylaxis-related basophil migration appears to be selective, because no significant changes were seen for other blood cells, or chemotactic factors, which may affect other effector cells, such as eosinophils.
The authors’ findings imply an important and specific role for basophils in the pathophysiology of human anaphylaxis and suggest that basophils migrate out of the circulation to target organs during anaphylaxis. The results could have long-term implications for development of novel biomarker assays for diagnosing anaphylaxis and therapeutic interventions to prevent anaphylaxis.
The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.