5 ± 0.7Bb 2.4 ± 1.2Bb 3.5 ± 0.7Bb 104 1.7 ± 0.6Bb 2.7 ± 0.5Bb 13.3 ± 4.4Aa 10.8 ± 2.3Aa 105 1.3 ± 0.2Bb 2.4 ± 1.5Bb 8.7 ± 0.8Aa 14.2 ± 1.6Aa 106 0.2 ± 0.1Bb 0.7 ± 0.6Bb 3.2 ± 1.9Bb 9.0 ± 2.3Aa 107 0.3 ± 0.3Bb 0.8 ± 0.6Bb 3.0 ± 2.4Bb 6.1 ± 2.3Bb 108 0.01 ± 0.0Bb 0.2 ± 0.1Bb 2.6 ± 2.6Bb 1.0 ± 0.2Bb L. marthii BAA-1595 103 2.3 ± 0.5Bb 2.0 ± 0.4Bb 2.2 ± 0.0Bb 4.5 ± 0.7Bb 104 1.5 ± 0.2Bb 0.6 ± 0.3Bb 4.0 ± 0.8Bb 7.7 ± 5.6Aa 105 0.5 ± 0.0Bb 2.0 ± 0.4Bb 5.3 ± 1.1Bb 18.0 ± 3.6Aa 106 0.6 ± 0.1Bb 1.3 ± 0.7Bb 7.3 ± 1.1Aa 5.5 ± 3.0Bb
107 0.2 ± 0.8Bb 0.3 ± 0.2Bb 2.5 ± 1.8Bb 3.2 ± 0.5Bb 108 2.8 ± 0.4Bb 0.02 ± 0.0Bb 1.1 ± 0.3Bb 2.0 ± 0.3Bb aBacteria were grown in TSB-YE for 18 h at 37 °C. The data are average of 3 experiments analyzed in duplicate. Values labeled with different letters (A, check details B, C, D or a, b, c, d) in a row or in a column are significantly different at P < 0.05. Figure 4 (a) Capture efficiency of MAb-coated paramagnetic beads from a cell suspension containing variable concentrations of L. monocytogenes . Data are the mean ± SD of three Copanlisib mouse independent assays performed in duplicate. (b) Photomicrograph showing capture of GFP-expressing L. monocytogenes using MyOne-2D12 (anti-InlA MAb). Beads, red arrow; bacteria, blue arrow; bar = 1 μm. All subsequent IMS experiments were performed using MyOne beads. The fluorescence microscopic image in Figure 4b shows the capture of L.
monocytogenes by MyOne-2D12. The capture efficiency of MyOne-2D12 and MyOne-3F8 was evaluated with bacteria grown
in the recommended enrichment broths, LEB or FB. MyOne-2D12 showed significantly higher (P < 0.05) capture of L. monocytogenes and L. ivanovii than other Listeria spp., and the capture efficiency was similar for LEB or only FB (Figure 5). The capture efficiency for MyOne-2D12 was comparable for the L. monocytogenes serotypes tested, including 4b (36.9%), 1/2a (27%), and 1/2b (28%), as well as for a strain of L. ivanovii (21.6%), and negligible capture of other Listeria spp. was observed (Figure 5a). MyOne-3F8 displayed similar capture efficiency for all Listeria spp. tested, irrespective of the enrichment broths used (Figure 5b). When the capture efficiency of MyOne-2D12, MyOne-3F8, and Dynabeads anti-Listeria was compared against a Listeria panel, MyOne-2D12 captured the most pathogenic Listeria. For all other Listeria spp., both MyOne-3F8 and Dynabeads anti-Listeria had similar values (Figure 5c). Thus, MyOne-2D12 is highly specific for the capture of pathogenic Listeria, and MyOne-3F8 and Dynabeads anti-Listeria displayed similar capture efficiency for all Listeria spp. tested. Figure 5 Capture efficiency and specificity of (a) MyOne-2D12 (InlA); (b) MyOne-3F8 (p30); and (c) MyOne-2D12 (InlA), MyOne-3F8 (p30), and Dynabeads anti- Listeria (Dynal). Bacteria were grown in FB or LEB, and the capture efficiency was determined using a bacterial concentration of ~106 CFU/mL. Data are the mean ± SD of three independent experiments. The capture efficiency of PMBs for L.