Yoshida Haruno, Goto Mieko, Fukushima Yasuto, Maeda Takahiro, Tsuyuki Yuzo, Takahashi Takashi
Laboratory of Infectious Diseases, Graduate School of Infection Control Sciences & Ōmura Satoshi Memorial Institute, Kitasato University, Japan.
Division of Clinical Laboratory, Sanritsu Zelkova Veterinary Laboratory, Japan.
Jpn J Infect Dis. 2021 Mar 24;74(2):129-136. doi: 10.7883/yoken.JJID.2020.382. Epub 2020 Aug 31.
This study evaluated the cell invasion ability (CIA) of Streptococcus canis isolates, and clarified the relationship between high-frequency CIA and its microbiological features. Of the companion animal-origin isolates (n = 117) that were obtained in 2017, 40 isolates were randomly selected with the host information, with two human blood-origin isolates included. CIA was measured using human colon carcinoma epithelium and the hemolytic activity (HA) using sheep blood, along with S. canis M-like protein (SCM) allele typing, sequence type (ST) determination, and antimicrobial resistance (AMR) phenotyping/genotyping. CIA measurements revealed that 19 and 24 isolates had high- and low-frequencies, respectively. HA assessment revealed that 24 and 19 isolates were categorized as high- and low- level, respectively. No difference was observed in the high-/low-level HA between the high- /low-frequency CIA populations. A significant difference was found in the high-/low-frequency CIA between the SCM group I/II populations. Additionally, a significantly higher CIA was found in the SCM allele type 10/type 11 than in the others. A significant association was observed between high-frequency CIA and the ST21/ST41 populations. No difference was found in the high-/low-frequency CIA between the presence and absence of the AMR phenotype/genotype. These observations suggest a relationship between high-frequency CIA and its microbiological characteristics (SCM allele type 10/type 11 or ST21/ST41).
本研究评估了犬链球菌分离株的细胞侵袭能力（CIA），并阐明了高频CIA与其微生物学特征之间的关系。在2017年获得的伴侣动物源分离株（n = 117）中，随机选择了40株带有宿主信息的分离株，并纳入了2株人血源分离株。使用人结肠癌细胞系测量CIA，使用绵羊血测量溶血活性（HA），同时进行犬链球菌M样蛋白（SCM）等位基因分型、序列型（ST）测定以及抗菌药物耐药性（AMR）表型/基因型分析。CIA测量结果显示，分别有19株和24株分离株具有高频和低频CIA。HA评估显示，分别有24株和19株分离株被归类为高水平和低水平HA。高频/低频CIA群体之间在高/低水平HA方面未观察到差异。在SCM I/II组群体的高频/低频CIA之间发现了显著差异。此外，SCM等位基因类型10/类型11的CIA显著高于其他类型。在高频CIA与ST21/ST41群体之间观察到显著关联。在有无AMR表型/基因型的情况下，高频/低频CIA之间未发现差异。这些观察结果表明高频CIA与其微生物学特征（SCM等位基因类型10/类型11或ST21/ST41）之间存在关联。
