Figure 2

Affinity determination of screening bacteriophage with EtCab protein. The binding capability of thirty randomly selected phages was found to be higher than that of the blank control (BC) and the negative control (NC). The positive control (PC) phages, designed to bind to the EtMIC3 protein, were prepared as shown in (A). Phages were diluted from 1.0 × 10¹² to 1.0 × 10⁶ pfu/10 μL and coated in each well of a 96-well plate. The binding abilities of phages Y, G, and V were greater than that of the NC phages, with phages Y and G exhibiting higher binding than phage V (B). When 1.0 × 10¹² pfu/10 μL of phages Y, G, and V were coated per well in a 96-well plate, their binding abilities to the recombinant EtCab protein and sporozoites lysates supposed those of the NC phages (C). The binding of the three phages to the EtCab protein was significantly inhibited by anti-EtCab antisera when compared to an irrelevant polyclonal antibody (PcAb) against the ΔHexon protein of fowl adenovirus serotype 4 (FAdV-4), which served as the negative antibody control (D). Each sample was tested in triplicate and the values represent the mean ± SD (n = 5). Statistical significance is denoted as follows: *P < 0.05, **P < 0.01, ***P < 0.001, and “ns” indicates no statistical difference.