英格诺苏斯链球菌（AGS）是口腔中的机会性人体病原微生物。乙溶血亚组的链球菌咽腺炎链球菌亚种分泌链球溶素S（SLS），不仅具有溶血活性，还对培养的人类细胞株具有细胞毒性。然而，SLS的详细作用机制和宿主细胞的细胞反应尚未完全阐明。为了确定产生SLS的乙溶血咽腺炎链球菌亚种的致病潜力，调查了对人类口腔鳞状细胞癌细胞HSC-2诱导SLS-依赖反应的能力，以确定产生SLS的乙溶血咽腺炎链球菌亚种的致病潜力。研究发现，在与产生SLS的乙溶血咽腺炎链球菌亚种的培养上清液共孵育的HSC-2细胞中，Ca2+内流以及早期生长反应（EGR）和活化蛋白-1（AP-1）等转录因子的即刻早期基因（IEG）表达显著增加。此外，这种SLS依赖性的表达增加在除jun外，通过Ca2+螯合显著抑制。这些结果表明，SLS引起细胞内Ca2+内流，随之大大增强IEG编码转录因子的表达。本研究的结果有助于了解产生SLS的AGS的致病性。 ©2023. Springer Nature Limited.

Anginosus group streptococci (AGS) are opportunistic human pathogens of the oral cavity. The β-hemolytic subgroup of Streptococcus anginosus subsp. anginosus secretes streptolysin S (SLS) and exhibits not only hemolytic activity but also cytotoxicity toward cultured human cell lines. However, the detailed mechanism of action of SLS and the cellular responses of host cells have not yet been fully clarified. To determine the pathogenic potential of SLS-producing β-hemolytic S. anginosus subsp. anginosus, the SLS-dependent response induced in the human oral squamous cell carcinoma HSC-2 cells was investigated to determine the pathogenic potential of SLS-producing β-hemolytic S. anginosus subsp. anginosus. This study revealed that the Ca2+ influx and the expression of immediate early genes (IEGs) encoding transcription factors such as early growth responses (EGRs) and activator protein-1 (AP-1) were greatly increased in HSC-2 cells incubated with the culture supernatant of SLS-producing β-hemolytic S. anginosus subsp. anginosus. Moreover, this SLS-dependent increase in expression was significantly suppressed by Ca2+ chelation, except for jun. These results suggest that SLS caused Ca2+ influx into the cells following greatly enhanced expression of IEG-encoding transcription factors. The results of this study may help in understanding the pathogenicity of SLS-producing AGS.© 2023. Springer Nature Limited.