Schizophyllum commune induces IL-17-mediated neutrophilic airway inflammation in OVA-induced asthma model mice.

Schizophyllum commune is a ubiquitous basidiomycetous fungus typically found across the world, which has been detected in indoor and outdoor air. Some studies indicated that sensitization to S. commune is correlated with asthma severity in patients. Patients with chronic severe or acute fatal asthma have neutrophil-dominant airway inflammation. We hypothesized that S. commune can exacerbate asthma. To test this hypothesis, we evaluated the direct immunomodulatory activities of S. commune in allergic airway inflammation induced by non-fungal sensitization. Ovalbumin (OVA)-induced asthma model mice were generated using wild-type (WT) and Il-17a-/-Il-17f-/- mice that were intratracheally exposed to S. commune, then immune responses in the lungs were assessed after 24 h. Intratracheal administration of S. commune in OVA-induced asthma model mice enhanced neutrophilic airway inflammation, increased the mRNA expression of CXCL1 and CXCL2 in the lungs, and provoked IL-17A, and IL-17F production in BAL fluid. In addition, neutrophilic airway inflammation was significantly inhibited in Il-17a-/-Il-17f-/- mice compared with those found in WT mice. We demonstrated that S. commune induces neutrophilic airway inflammation in OVA-induced asthma model mice, and IL-17A and IL-17F had central roles in this activity. As S. commune inhabits the general environment, including indoor and outdoor air, our results suggested that S. commune is a causative agent of asthma exacerbation. This study has provided clues regarding the mechanisms behind fungi and asthma exacerbation.

Evaluation of a Hypertensive Rat Model Using Peripheral Blood Neutrophil Activity, Phagocytic Activity and Oxidized LDL Evaluation.

BACKGROUND/AIM: A system is being developed that can be used to easily evaluate the health condition of an individual with the help of trace amounts of a blood sample by focusing on xenobiotics. The system is called "Multimodal homeostasis evaluation system" (measurement of neutrophil activity, phagocytic activity of phagocytes and quantification of oxidized LDL (OxLDL)). To elucidate the possibility of using this system as an evaluation system for the health condition of an individual, clearly explaining the changes in various diseases is essential. In this study, evaluations were carried out using hypertensive model animals. MATERIALS AND METHODS: Spontaneously hypertensive model rats SHR/NCrlCrlj and control rats WKY/NCrlCrlj were raised for 10 weeks from 6 to 16 weeks of age and their blood pressure was measured over time. Blood neutrophil activity (superoxide anion (O2•-) generation and myeloperoxidase (MPO) activity) and phagocytic activity of phagocytes was measured by our developed apparatus (a simple prototype device under development). OxLDL was measured by an ELISA kit, and biochemical markers were measured using the blood sample. RESULTS: Compared to WKY rats of the control group, systolic blood pressure, diastolic blood pressure, and mean blood pressure of SHR rats increased significantly with age. In SHR rats, there was a significant elevation in O2•- generation and MPO activity of neutrophils, alanine aminotransferase and triglycerides of blood, while phagocytic activity, OxLDL, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, total cholesterol and total-bilirubin decreased. CONCLUSION: In the hypertensive model, biochemical markers were found to have a relationship with O2•- generation, MPO activity, phagocytic activity of phagocytes, and OxLDL. This system is expected to be useful for clinical monitoring of hypertension diseases.