Role of structural alteration of bacterial lipopolysaccharide on bacterial evasion of host innate immune responses

2014 Fiscal Year Final Research Report

• Project/Area Number: 24590523
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Bacteriology (including Mycology)
• Research Institution: Kyoto University
• Principal Investigator: MATSUURA Motohiro 京都大学, 医学(系)研究科(研究院), 非常勤講師 (20150089)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 細菌リポ多糖LPS / 自然免疫 / 細菌感染 / 免疫回避

Outline of Final Research Achievements

Salmonella Typhimurium was used as representative Gram-negative bacteria and generated mutant strains having reduced number of acyl groups in its lipopolysaccharide (LPS). Culture cells of mouse and human origins were infected by the wild and mutant strains and revealed the effect of structural alterations of LPS to less-acylated types on evasion of host innate immune responses that lead to enhancement of bacterial pathogenicity. Among the markers of innate immune responses, cytokine inducing activity was down-regulated by the less-acylated mutants in human cells largely caused by evasion of TLR4 stimulation. While phagocytic activity was weakened by the mutants even in mouse cells without TLR4 dependency and this evasion was suggested to occur generally in wide variety of host origins.

Free Research Field

感染免疫（細菌感染に対する宿主自然免疫応答）