Table 7.

Effect of polymyxin B on the invasion of HEp-2 cells in presence of the MUC2 mucin.

Bacteria	Polymyxin B	Invasion HEp-2	Invasion HEp-2 + polymyxin B
M. avium 104	4.5 ± 0.5 × 105	8.3 ± 0.4 × 104	8.0 ± 0.5 × 104
MAH 4B2	2.5 ± 0.6 × 103∗	3.2 ± 0.5 × 103∗	6.4 ± 0.4 × 102∗&

Inoculum was 4.5 × 10⁵ for M. avium and 3 × 10⁵ for MAH 4B2. Bacteria were incubated with polymyxin for 4 hours, and the diluted and plated bacteria were placed on the monolayers with or without polymyxin for 2 h; then extracellular bacteria were removed, and HEp-2 cells were lysed. The lysate was plated for quantification of colony forming units. ^∗p < 0.5 for the comparison between M. avium 104 and 4B2. &p < 0.5 for the comparison between MAH 4B2 invasion of HEp-2 cells with and without polymyxin B.