Gating strategy for determination of the binding efficiency of ACE2 variants with SARS-CoV-2 or SARS-CoV S1-Fc protein.

(A-B) Main cell population was identified and gated on Forward and Side Scatter. Single cells were further gated on FSC-A and FSC-H. The gated cells were plotted by FITC-A (zsGreen, as the ACE2 expressing population) and APC-A (S1-Fc bound population). The FITC-A positive cell population was plotted as a histogram to show the S1-Fc positive population as Fig 2B. The binding efficiency was defined as the percent of S1-Fc binding cells among the zsGreen positive cells. Shown are FACS plots representative of those that have been used for the calculations of binding efficiencies of ACE2 variants with S1-Fc. This experiment was independently repeated three times with similar results.
(ZIP)

(A-B) 本研究通过前向散射光（Forward Scatter）与侧向散射光（Side Scatter）门控圈选并鉴定主要细胞群；随后借助前向散射光面积（FSC-A）与前向散射光高度（FSC-H）进一步门控圈选出单细胞。将圈定的细胞以异硫氰酸荧光素通道（FITC-A，zsGreen标记，对应血管紧张素转换酶2（ACE2）阳性表达细胞群）和别藻蓝蛋白通道（APC-A，对应结合S1-Fc的细胞群）绘制散点图。将FITC-A阳性细胞群以直方图形式展示，以呈现S1-Fc阳性细胞群，对应图2B。结合效率定义为zsGreen阳性细胞中结合S1-Fc的细胞占比。本荧光激活细胞分选术（Fluorescence-Activated Cell Sorting, FACS）图谱为用于计算ACE2变体与S1-Fc结合效率的代表性实验结果。该实验独立重复三次，所得结果均一致。(ZIP)