A Single Mutation of VP2 is Responsible for the Lethality and Antigenicity Differences between Novel Variant and Very Virulent IBDV Strains

Figure 6

Influence of residue 279 mutation on antiserum neutralization of IBDVs. (a) Neutralizing test of HLJ0504 antiserum against the homologous virus rHLJ0504, point mutation virus rHLJ-D279N, and heterogenous virus SHG19. (b) Neutralizing test of SHG19 antiserum against the homologous virus rSHG19, point mutation virus rSHG-N279D, and heterogenous virus rHLJ0504. (c) Binding capacities of HLJ0504 antiserum to the homologous VP2 protein HLJ-VP2, point-mutant VP2 protein HLJVP2-D279N, and heterologous VP2 protein SHG-VP2 determined via IFA. Green indicates the HLJ0504 antiserum-binding positive cell. Red indicates different VP2 protein expression cells. (d) Percentage of HLJ0504 antiserum-binding positive cells (green fluorescence)/different VP2 protein expression cells (red fluorescence). Error bars represent the SD. ; ; ; .

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