Study in the prevalence of cryptococcal meningitis and its mycological and immunological background in China

• Project/Area Number: 16H05841
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 海外学術
• Research Field: Infectious disease medicine
• Research Institution: Tohoku University
• Principal Investigator: Kawakami Kazuyoshi 東北大学, 医学系研究科, 教授 (10253973)
• Research Collaborator: ISHII KEIKO ; ZHANG TIANTUO ; ZHU JIAXIN ; YUAN XIAOLIANG
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥12,740,000 (Direct Cost: ¥9,800,000、Indirect Cost: ¥2,940,000); Fiscal Year 2018: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2017: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2016: ¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000)
• Keywords: 中国 / クリプトコックス / 髄膜炎 / 潜在性感染 / 免疫学的背景

Outline of Final Research Achievements

We investigated the prevalence situation of cryptococcosis and its mycological and immunological background in China in collaboration with the Third Affiliated Hospital of Sun Yat-Sen University and the First Affiliated Hospital of Gannan Medical University in Guangdong and Jiangxi Province, respectively. We found that sixty percent of thirty-five cryptococcosis patients did not have any underlying diseases which affected their immune condition, including HIV infection. In addition, we attempted to develop IFN-γ-releasing assay for detection of latent infection with Cryptococcus neoformans. We detected higher IFN-γ production by peripheral blood lymphocytes from the patients upon stimulation with 98 kDa mannoprotein, a known T cell-specific antigen of this fungal pathogen, than those from control subjects.

Academic Significance and Societal Importance of the Research Achievements

わが国同様に、中国でも免疫不全を背景にしないクリプトコックス髄膜炎が少なくないことを明らかにするとともに、結核以外では未だ報告がないクリプトコックスの潜在性感染を検出するためのIFN-γ-releasing assayの開発につながる研究として学術的、社会的意義を有する。本研究を通して潜在性クリプトコックス感染症を事前に検出することができれば、抗真菌薬治療によってエイズ合併クリプトコックス髄膜炎の発症予防につながる可能性が期待できる。