Figure 3

The proteolytic rIde _Ssuis constructs modulate IgM binding to the surface of erythrocytes after incubation in αEry sera. (A, B) Flow cytometry analysis of IgM and IgG binding to ovine erythrocytes after incubation with porcine sera drawn pre, post prime or post booster vaccination with ovine erythrocytes (generation of αEry sera). (C, D) Binding of specific IgM antigen to the surface of ovine erythrocytes is significantly reduced after pretreatment of a post prime αEry serum with rIde _Ssuis and rIde _Ssuis _homologue. The post prime αEry serum was preincubated with the indicated Ide _Ssuis constructs and as a control with MRP. (A, C) The percentage of erythrocytes labelled with IgM or IgG and (B, D) the mean fluorescence intensities are shown. αEry sera were inactivated in these assays to allow flow cytometric analysis of erythrocytes. Bars and error bars represent mean values and standard deviations, respectively. Significant differences are indicated (***p < 0.001) except for differences between pre and post vaccination sera.