Japanese cedar pollen upregulates the effector functions of eosinophils

Abstract

Background Symptoms of rhinitis and asthma can be exacerbated during Japanese cedar pollen (JCP)-scattering season, even in subjects who are not sensitized to JCP, suggesting that innate immune responses may contribute to this process. We previously reported that house dust mite directly activates the effector functions of eosinophils. Similar mechanisms may play roles in the JCP-related aggravation of allergic diseases. Objective To investigate whether JCP or Cry j 1, a major allergen of JCP, can modify the effector functions of eosinophils. Methods Eosinophils isolated from the peripheral blood of healthy donors were stimulated with either JCP or Cry j 1, and their adhesion to human intercellular adhesion molecule-1 was measured using eosinophil peroxidase assays. The generation of eosinophil superoxide anion (O 2 − ) was measured based on the superoxide dismutase-inhibitable reduction of cytochrome C. Concentrations of eosinophil-derived neurotoxin in the cell media were measured by enzyme-linked immunosorbent assay as a marker of degranulation. Results Both JCP and Cry j 1 directly induced eosinophil adhesiveness, generation of O 2 − , and release of eosinophil-derived neurotoxin. Both anti-αM and anti-β2 integrin antibodies blocked all of these eosinophil functions induced by JCP and Cry j 1. Similarly, PAR-2 antagonists also partially suppressed all of these effector functions induced by JCP and Cry j 1. Conclusion JCP and Cry j 1 directly activate the functions of eosinophils, and both αMβ2 integrin and partly PAR-2 are contributed to this activation. Therefore, JCP-induced eosinophil activation may play a role in the aggravation of allergic airway diseases in nonsensitized patients as well as in JCP-sensitized patients.

Immune modulation and COVID 19 in the Asia‐Pacific region

“…Japanese cedar pollinosis (JCP) is seasonal allergic rhinitis caused by the Japanese cedar (JC), and it is the most common allergic disease in Japan. The prevalence of JCP in Japan has been rising dramatically and has increased from 16% in 2008 to more than 38% in 2019 4,5 . The current study assessed the effects of sublingual immunotherapy (SLIT) treatment using JC pollen extracts on PBMCs derived from JCP patients.…”

“…| 923 SHAMJI and BOYLE in 2019. 4,5 The current study assessed the effects of sublingual immunotherapy (SLIT) treatment using JC pollen extracts on PBMCs derived from JCP patients. The study included 8 healthy controls, 16 JCP patients that are not treated with SLIT, and 30 JCP patients that are treated with SLIT.…”