FIG. 4.
Binding activities of selected ZEBOV GP1,2 RBR-Fc proteins. (A) RBR-Fcs 1, 4, and 7 (200 nM) were incubated with 293T or Vero E6 cells (permissive) or with Jurkat lymphocytes (nonpermissive). Cell surface binding was analyzed by flow cytometry, using protein A-Alexa Fluor 488 to detect the Fc portion of the RBR conjugate. (B) Binding of RBR-1-Fc and RBR-12-Fc to 293T, Vero E6, or Jurkat cells was determined and analyzed as in panel A. In all experiments, rabbit Fc served as a negative control. The averages of two or more experiments are shown. Bars represent the percentages of cells that bound the indicated RBR-Fc proteins. Error bars indicate standard deviations. Significance (relative to RBR-1-Fc) was determined by Student's t test. *, P < 0.05.