Fibrinogen binding to platelets as determined by flow cytometry
| . | Mean intensity* . | |||
|---|---|---|---|---|
| Not preincubated . | P . | Inhibition after preincubation with anti-Stx1 (%) . | Inhibition after preincubation with Reopro (%) . | |
| Unstimulated platelets | 0.42 | |||
| Stx1 10 pg/mL | 2.18 | ns | 36 | 53 |
| Stx1 100 pg/mL | 5.27 | < .01 | 30 | 82 |
| Stx1 1 ng/mL | 3.04 | < .05 | 55 | 72 |
| Stx1 10 ng/mL | 4.02 | < .005 | nt | nt |
| Stx1B 10 pg/mL | 4.39 | < .05 | nt | nt |
| Stx1B 100 pg/mL | 8.47 | < .05 | 17 | nt |
| Stx1B 1 ng/mL | 4.05 | < .05 | 0 | nt |
| Stx1B 10 ng/mL | 4.51 | < .01 | 55 | nt |
| . | Mean intensity* . | |||
|---|---|---|---|---|
| Not preincubated . | P . | Inhibition after preincubation with anti-Stx1 (%) . | Inhibition after preincubation with Reopro (%) . | |
| Unstimulated platelets | 0.42 | |||
| Stx1 10 pg/mL | 2.18 | ns | 36 | 53 |
| Stx1 100 pg/mL | 5.27 | < .01 | 30 | 82 |
| Stx1 1 ng/mL | 3.04 | < .05 | 55 | 72 |
| Stx1 10 ng/mL | 4.02 | < .005 | nt | nt |
| Stx1B 10 pg/mL | 4.39 | < .05 | nt | nt |
| Stx1B 100 pg/mL | 8.47 | < .05 | 17 | nt |
| Stx1B 1 ng/mL | 4.05 | < .05 | 0 | nt |
| Stx1B 10 ng/mL | 4.51 | < .01 | 55 | nt |
ns indicates not significant; for other abbreviations, see Table 1.
Numbers represent the median of mean fluorescence intensity of the entire cell population after subtraction of the background fluorescence (chicken-antihuman insulin-FITC). Results from 6 experiments for Stx1 and 5 experiments for Stx1B are presented. Inhibition experiments with anti-Stx1 antibody were carried out 4 times with Stx1 and twice with Stx1B. Inhibition experiments with Reopro were carried out twice.P values compare the median for each stimulant with the unstimulated platelets.