FIG 4.

Apically Administered Sal4 Inhibits STm Invasion in Enteroid and HIO Monolayers. Monolayers of Enteroids and HIOs were infected for 2 h with 50 μL 0.1 OD₆₀₀ OSTm WT or STm ΔoafA (final concentration 0.01 OD₆₀₀). Additional treatments were either 1 µg/mL Sal4 mIgA, Sal4 dIgA or Sal4 IgG or no antibody. STm invasion was measured through gentamicin invasion assay. Results show all antibodies significantly reduced invasion of WT STm, but not STm ΔoafA (Fig. 3A and B). *, P < 0.05, one-way ANOVA with Tukey post test. Invasion assays are combined data from (n = 3) biological replicates.