Schnitzler N, Haase G, Büssing A, Kaufhold A, Beyhs P, Podbielski A
Institute of Medical Microbiology, Technical University (RWTH) Aachen, Germany.
Med Microbiol Immunol. 1995 May;184(1):17-22. doi: 10.1007/BF00216785.
M protein is thought to contribute to the ability of non-opsonized group A and group G streptococci (GAS and GGS, respectively) to resist phagocytosis by polymorphonuclear leukocytes. In previous studies, correlation between M protein expression and phagocytosis was determined by incubating these pathogens in human blood and comparing colony-forming bacterial counts prior to and after exposure to blood (direct bactericidal assay; DBA). Here, we report the application of flow cytometry to measure GAS and GGS resistance to phagocytosis. The results of the assays were in complete agreement with those from DBAs. Nevertheless, flow cytometry was regarded as superior to DBA because of its speed and potential uses for quantitative studies. In addition, the use of anti-CD11b monoclonal antibody for granulocyte staining guaranteed a non-compromized granulocyte function. The optimized protocol for flow cytometry presented here could be utilized to directly measure the involvement of individual protein types in bacterial resistance to phagocytosis.
M蛋白被认为有助于A组和G组非调理化链球菌（分别为A组链球菌和G组链球菌）抵抗多形核白细胞的吞噬作用。在先前的研究中，通过将这些病原体与人血一起孵育，并比较暴露于血液前后的菌落形成细菌计数（直接杀菌试验；DBA）来确定M蛋白表达与吞噬作用之间的相关性。在此，我们报告了应用流式细胞术来测量A组链球菌和G组链球菌对吞噬作用的抗性。检测结果与直接杀菌试验的结果完全一致。然而，由于其速度和在定量研究中的潜在用途，流式细胞术被认为优于直接杀菌试验。此外，使用抗CD11b单克隆抗体进行粒细胞染色可确保粒细胞功能不受影响。本文介绍的流式细胞术优化方案可用于直接测量个体蛋白类型在细菌抗吞噬作用中的参与情况。
