Immunochromatography for rapid detection of Streptococcus agalactiae in pregnant women

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K10684
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Obstetrics and gynecology
• Research Institution: Kitasato University
• Principal Investigator: Takayama Yoko 北里大学, 医学部, 准教授 (80286278)
• Co-Investigator(Kenkyū-buntansha): 花木 秀明 北里大学, 北里生命科学研究所, 特任教授 (60286747)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: Streptococcus agalactiae / GBS特異 Sip 抗原 / イムノクロマト法 / 迅速診断 / 診療所

Outline of Final Research Achievements

We evaluated an immunochromatography method for rapid detection of GBS-specific surface immunogenic protein (Sip) using anti-Sip monoclonal antibodies.
A total of 377 cervical and vaginal swabs collected during weeks 35 to 37 of gestation were inoculated into GBS medium F and incubated. Growth of microorganisms and production of red/orange pigment were assessed by observation. Then culture extracts were subjected to immunochromatography and were also inoculated onto chromID Strepto B (STRB) medium. Of the 377 samples, 54 (14.3%) were positive for GBS by immunochromatography after incubation in GBS medium F. On the other hand, GBS was isolated from 58 (15.4%) of the 377 samples by culture with GBS medium F and STRB medium.
Immunochromatography was comparable to culture on STRB medium for detecting GBS, indicating that this method could be used clinically for GBS screening in pregnant women even at small institutions.

Free Research Field

感染対策、感染症

Academic Significance and Societal Importance of the Research Achievements

我が国の産婦人科は個人病院が多く、そのほとんどが GBS 選択培地を用いて GBS を検出しており、GBS 保菌妊婦の見逃しが問題となっている。
簡便で費用対効果の面でも優れた新規 GBS 検出方法の確立は、GBS スクリーニング検査の更なる普及と検査精度の上昇につながり、GBS 感染症の発症率低下が期待できる。また、適切な抗菌薬による治療へと結びつき、近年報告されているペニシリン低感受性溶連菌などの薬剤耐性菌への抑制効果も期待される。