Table 3.
Quantitation of HEp-2 Cells with Adherent Bacteria in the Absence and Presence of Antisera
|
Percent mean ± standard error of mean, of HEp-2 cells with adherent bacteria in the ranges showna(MOI = 106 bacteria:105 recto-anal junction squamous epithelial cells) |
||||||||
---|---|---|---|---|---|---|---|---|---|
STEC |
No antisera |
Pooled antisera |
Pooled hyperimmune bovine sera |
||||||
serogroup tested | Bacterial adherence pattern | >10 | 1–10b | Bacterial adherence pattern | >10 | 1–10 | Bacterial adherence pattern | >10 | 1–10 |
O26 | Diffuse, moderate | 1.5 ± 1.5 | 86.2 ± 13.9 | Non-adherent | 0.8 ± 0.8 | 38.2 ± 10.2 | Non-adherent | 3.57 ± 2.1 | 27.4 ± 0.4 |
O113 | Diffuse, moderate | 0.7 ± 0.7 | 79.35 ± 4.4 | Non-adherent | 0 | 23.7 ± 5.7 | Non-adherent | 0 | 17.3 ± 5.6 |
O103 | Diffuse, moderate | 0 | 59 ± 4 | Non-adherent | 2.1 ± 2.1 | 42.5 ± 5.9 | Non-adherent | 0 | 34.65 ± 5.4 |
O121 | Diffuse, moderate | 0 | 81.2 ± 15.2 | Non-adherent | 1.4 ± 1.4 | 40.8 ± 0.8 | Non-adherent | 0 | 37.5 ± 7.5 |
O45 | Diffuse, moderate | 3.2 ± 3.2 | 54.3 ± 0.7 | Non-adherent | 4.2 ± 4.2 | 18.44 ± 4.9 | Non-adherent | 5.4 ± 5.4 | 17.5 ± 7.5 |
O145 | Diffuse, moderate | 0 | 75.5 ± 7.5 | Non-adherent | 1.5 ± 1.5 | 43.15 ± 5.2 | Non-adherent | 3.6 ± 3.6 | 26.4 ± 11.4 |
O111 | Diffuse, moderate | 0 | 58.5 ± 6.5 | Non-adherent | 1.3 ± 1.3 | 17.5 ± 2.5 | Non-adherent | 1.4 ± 1.4 | 17.1 ± 2.1 |
O157 | Diffuse, moderate | 0 | 78.3 ± 9.3 | Non-adherent | 0 | 26 ± 4 | Non-adherent | 0 | 37.6 ± 6.2 |
Average of two trials conducted for two strains, A and B, of each serotype, except for serotype O121:H19 for which only one strain was available, is shown. Each trial had one slide per bacterial group. Each slide in turn had six technical replicates in separate chambers on it; 10–20 well-dispersed HEp-2 cells were evaluated per chamber. Percent means for ranges used to determine “moderate or strong” adherence, in the absence of any antisera, are shown in bold.
Number of bacteria adhering to each HEp-2 cell is shown as a range of > 10, and 1–10. Number of HEp-2 cells without bacteria is not shown.
MOI, multiplicity of infection; STEC, Shiga toxin–producing Escherichia coli.