New dermatomycosis -how entomopathogenic fungi attacked human?

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K16634
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 49050:Bacteriology-related
• Research Institution: Chiba University
• Principal Investigator: Ban Sayaka 千葉大学, 真菌医学研究センター, 助教 (90834664)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 皮膚糸状菌 / 昆虫病原性糸状菌 / 分類 / リスク評価 / Cordycipitaceae / Lecanicillium / Parengyodontium album

Outline of Final Research Achievements

We newly reported Lecanicillium coprophilum was isolated from dermatitis patients, and investigated its biological properties and distribution in the human living environment to evaluate their pathogenic risks. That is related to insect pathogens and Parengyodontium album that has been known causing keratitis, cutaneous infection, rarely endocarditis. However, proteinase and chitinase activities were not detected in the culture, and the fungi could not grow at more than 35℃. No isolate was obtained from room air for 3 years. Thus, we concluded L. coprophilum is not air-borne nor human pathogen.

Free Research Field

菌学、感染症、医真菌

Academic Significance and Societal Importance of the Research Achievements

ヒトの皮膚の炎症部位から昆虫病原菌の仲間の真菌が分離された。そこで本菌がヒトへ感染することが可能か検証した。屋内環境中の浮遊量は検出されず、タンパク質分解酵素も産生しないか微量であった。抗真菌剤は効果が薄かったが、生育適正温度が体温の35℃以下でしかなかったため、ヒトへ加害することは極端に稀であると結論づけた。リスク評価では病原性が全くゼロであることを示すのは難しいが、本菌群は病原菌と呼べる要素は何一つないと言える。