Table 3.
Enhanced cell surface Lewis antigen expression is cholesterol-specific
| fold increase compared to parallel cholesterol-free culture | ||||
|---|---|---|---|---|
| Lewis X | Lewis Y | |||
| mean ± SEM (n) | P value | mean ± SEM (n) | P value | |
| cholesterol | 2.96 ± 0.22 (5) | .0008 | 2.48 ± 0.10 (4) | .0007 |
| β- sitosterol | 1.80 ± 0.47 (4) | 0.19 | 1.19 ± 0.13 (3) | 0.28 |
| taurocholate | 0.64 ± 0.16 (4) | 0.12 | 0.84 ± 0.20 (3) | 0.52 |
Lewis antigens were quantitated in replicate whole-cell ELISA analyses of pairwise cultures of H. pylori G27 grown in the presence or absence of 130 μM cholesterol, or an equal concentration of β-sitosterol or sodium taurocholate. The antigen load was 300 ng cellular protein per well. Ratios for plus:minus cholesterol were calculated from duplicate net absorbance readings in each assay, and ratios determined in three to five independent ELISA runs were then averaged. P values were calculated in two-tailed Student t-tests for the null hypothesis that the ratio equals 1.