Monoclonal Antibodies Specific to the Extracellular Domain of Histidine Kinase YycG ofStaphylococcus epidermidisInhibit Biofilm Formation
Monoclonal Antibodies Specific to the Extracellular Domain of Histidine Kinase YycG ofStaphylococcus epidermidisInhibit Biofilm Formation
复制标题
表皮葡萄球菌组氨酸激酶 YycG 胞外域特异性单克隆抗体抑制生物膜形成
DOI：
10.3389/fmicb.2020.01839
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发表时间：
2020-08-07
影响因子：
5.2
通讯作者：
Qu, Di
中科院分区：
文献类型：
--
作者：
Lyu, Zhihui;Shang, Yongpeng;Qu, Di
表皮葡萄球菌常与生物膜相关感染相关。生物膜大大降低了常规抗生素和宿主免疫系统的功效。在表皮葡萄球菌生物膜形成过程中，YycG/YycF双组分系统起主要作用，以前的研究表明，针对表皮葡萄球菌YycG激酶胞质HATPase_c结构域的抑制剂具有杀菌和生物膜杀伤活性。因此，我们推测针对YycG胞外区（YycG（ex））的单克隆抗体（mAb）可以阻断信号转导，从而影响S.表皮在这项研究中，我们筛选出两个YycG（ex）特异性mAb，显示出对靶点的最高亲和力，mAb 2F 3和1H 1。这些单克隆抗体抑制S.在160 μ g/mL的浓度下，相对于正常小鼠IgG对照，mAb 2F 3和1H 1分别引起78.3%和93.1%的生物膜减少。当与YycG（ex）mAb共培养时，S.表皮细胞的初始粘附能力降低，抗体处理进一步导致多糖细胞间粘附素的合成和生物膜形成相关蛋白质编码基因的转录水平显著降低。最后，我们确定由两个YycG（ex）单克隆抗体识别的表位位于YycG（ex）结构域的59-70位氨基酸内。提示YycG（ex）结构域有可能作为预防S.表皮生物膜感染。
Staphylococcus epidermidisis frequently associated with biofilm-related infections. Biofilms drastically reduce the efficacy of conventional antibiotics and the host immune system. InS. epidermidisbiofilm formation, a major role is played by the YycG/YycF two-component system, and previous findings have indicated that inhibitors targeting the cytoplasmic HATPase_c domain of YycG kinase inS. epidermidisexhibit bactericidal and biofilm-killing activities. Therefore, we hypothesized that monoclonal antibodies (mAbs) against YycG extracellular (YycG(ex)) domain would block the signal transduction and influence the biofilm formation ofS. epidermidis. In this study, we screened out two YycG(ex)-specific mAbs showing the highest affinity for the target, mAbs 2F3 and 1H1. These mAbs inhibitedS. epidermidisbiofilm formation in a dose-dependent manner, and at a concentration of 160 mu g/mL, mAbs 2F3 and 1H1 caused 78.3 and 93.1% biofilm reduction, respectively, relative to normal mouse IgG control. When co-cultivated with YycG(ex)mAbs,S. epidermidiscells showed diminished initial-adherence capacity, and the antibody treatment further led to a marked decrease in the synthesis of polysaccharide intercellular adhesin and in the transcriptional level of genes encoding proteins involved in biofilm formation. Lastly, we determined that the epitopes recognized by the two YycG(ex)mAbs are located within aa 59-70 of the YycG(ex)domain. It indicates that the YycG(ex)domain may be a potential candidate as a vaccine for the prevention ofS. epidermidisbiofilm infections.