Roles of cleaved immunoglobulins in pathophysiology of lepromatous leprosy

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K08946
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 54030:Infectious disease medicine-related
• Research Institution: National Institute of Infectious Diseases
• Principal Investigator: Ato Manabu 国立感染症研究所, ハンセン病研究センター 感染制御部, 部長 (20392318)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 免疫グロブリン / ハンセン病 / 免疫グロブリン様受容体

Outline of Final Research Achievements

Host immunity plays a role in the symptoms of leprosy and the severity of infection. However, it is unclear what molecular mechanisms are responsible for the predominance of Th2 immune responses in Lepromatoid leprosy. Recently, the immunoglobulin-like receptor LILRA2 was identified as a candidate biomarker for Lepromatoid-type leprosy. To analyze LILRA2 expression in leprosy lesions, we attempted to detect its binding by LILRA2-Fc fusion protein in 13 leprosy skin tissue samples. As a result, positive cells were found in leprosy skin tissues, but positive reactions were observed in mast cells, not in infected cells. Because mast cells nonspecifically react with some ligands , further investigation is needed to determine the relationship between this finding and the pathogenesis of leprosy.

Free Research Field

感染症学

Academic Significance and Societal Importance of the Research Achievements

本研究は、L型ハンセン病病変部位のLILRA2発現および免疫グロブリン部分分解産物の存在について確認し、ヒトから分離したLILRA2発現白血球亜群細胞及びハンセン病動物感染モデルを用いて、免疫グロブリン分解産物がらい菌感染免疫応答へ及ぼす影響を解析し、L型ハンセン病の誘導因子を解明することを目的とする。これらが判明すれば、ハンセン病の病態の解明につながり、ハンセン病の予防、早期診断と早期治療の開始、発症ハイリスク者の発症予防対策等に対し、大いに貢献することが可能となる。