Genome analysis for innate immune memory

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K07239
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Genome biology
• Research Institution: Tohoku University
• Principal Investigator: Fuse Naoyuki 東北大学, 薬学研究科, 助教 (80321983)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 自然免疫 / 記憶 / ショウジョウバエ

Outline of Final Research Achievements

Innate immunity is an evolutionarily conserved primitive defense system, and is currently realized to carry memory capacity of immune response as adaptive immunity does. However, its mechanism remains to be elusive. We study “innate immune memory” using fruit fly, Drosophila, that eliminates pathogens solely via innate immunity. Here, we found that comparing with naive flies, the flies trained to primary infection with some kinds of bacteria showed higher resistance against secondary infection with pathogenic bacteria. From RNA-Seq analysis, we identified 398 genes, whose expressions after secondary infection were up-regulated in training-dependent manners. These genes significantly enriched the immune genes regulated by Spt-Ada-Gcn5 acetyltransferase (SAGA), a histone modification complex. These results suggest that epigenetic reprogramming for gene expression might be involved in innate immune memory in insects as well as in mammals.

Free Research Field

ゲノム科学

Academic Significance and Societal Importance of the Research Achievements

「自然免疫の記憶」は臨床的にも注目されている。例えば、BCGワクチンは、結核菌に対するワクチンとして広く利用されているが、他の様々な感染症に対しても抵抗性を示すことが知られていた。近年、この現象が「自然免疫の記憶」に因ることが明らかになり、将来起こるかもしれない新型の感染症にも応用できる可能性が示された。本研究は、「自然免疫の記憶」の基本的なメカニズム解明することを目指しており、その成果は、「自然免疫の記憶」を応用した、幅広い病原体に応答できるワクチンの開発に繋がる可能性がある。