FIG 7.

Recombinant AmOmpA and ApOmpA competitively inhibit A. marginale infection of endothelial cells. RF/6A cells were incubated with GST alone, GST-AmOmpA (A and B), or GST-ApOmpA (C and D) proteins for 1 h. A. marginale DC organisms were then added and incubated with the cells in the presence of recombinant protein for 2 h. After washing to remove unbound bacteria, host cells were incubated for 48 h and subsequently examined by immunofluorescence microscopy to determine the percentage of infected cells (A and C) and AmVs per cell (B and D). Results are the means ± SD from triplicate samples and are representative of three independent experiments with similar results. Statistically significant (*, P < 0.05) values are indicated.