Fan Shunyi, Tsai Catherine Jia-Yun, Loh Jacelyn Mei San, Proft Thomas
Department of Molecular Medicine, School of Medical Sciences, The University of Auckland, Auckland 1010, New Zealand.
Maurice Wilkins Centre for Molecular Biodiscovery, Auckland 1010, New Zealand.
Microorganisms. 2026 Feb 3;14(2):357. doi: 10.3390/microorganisms14020357.
A Group A Streptococcus (GAS, ) is an exclusively human pathogen whose virulence is driven by a diverse array of surface structures, secreted toxins, and immune evasion mechanisms. Central to its pathogenicity is the M protein, a surface-anchored molecule that inhibits phagocytosis by interfering with complement deposition and binding host factors such as fibrinogen. GAS also secretes a wide range of toxins and enzymes that damage tissues and disrupt host defences. Streptolysin O and streptolysin S are potent cytolysins that lyse immune cells and contribute to tissue necrosis. Pyrogenic exotoxins (such as SpeA and SpeC) act as superantigens, triggering massive, dysregulated T cell activation and cytokine release, an underlying mechanism in streptococcal toxic shock syndrome. Additional factors like DNases and streptokinase facilitate bacterial spread by breaking down host tissue and counteracting neutrophil extracellular traps (NETs). Immune evasion is further supported by the production of enzymes that interfere with complement functions, like the cleavage of chemokines and the targeting of antibodies. Together, these virulence determinants allow GAS to cause a wide spectrum of diseases, ranging from uncomplicated pharyngitis and impetigo to invasive conditions like necrotising fasciitis and sepsis. This review provides a timely overview of the important GAS virulence factors and an update on the current vaccine landscape.
A组链球菌（GAS）是一种仅感染人类的病原体，其毒力由多种表面结构、分泌毒素和免疫逃避机制驱动。其致病性的核心是M蛋白，一种表面锚定分子，通过干扰补体沉积和结合宿主因子（如纤维蛋白原）来抑制吞噬作用。GAS还分泌多种毒素和酶，这些毒素和酶会损害组织并破坏宿主防御。链球菌溶血素O和链球菌溶血素S是强大的细胞溶素，可裂解免疫细胞并导致组织坏死。致热外毒素（如SpeA和SpeC）作为超抗原，引发大量、失调的T细胞活化和细胞因子释放，这是链球菌中毒性休克综合征的潜在机制。其他因素如脱氧核糖核酸酶和链激酶通过分解宿主组织和对抗中性粒细胞胞外陷阱（NETs）促进细菌传播。干扰补体功能的酶的产生进一步支持了免疫逃避，如趋化因子的裂解和抗体的靶向作用。这些毒力决定因素共同使GAS能够引起广泛的疾病，从不复杂的咽炎和脓疱病到坏死性筋膜炎和败血症等侵袭性疾病。本综述及时概述了重要的GAS毒力因子，并更新了当前的疫苗情况。
