Relationship Between PMN Adhesion and CD64 Expression After Activation by IFN-γ
| Concentration of IFN-γ (U/mL) . | Experiment No. 1 . | Experiment No. 2 . | Experiment No. 3 . | Experiment No. 4 . | ||||
|---|---|---|---|---|---|---|---|---|
| % CD64 . | % Adhesion . | % CD64 . | % Adhesion . | % CD64 . | % Adhesion . | % CD64 . | % Adhesion . | |
| 0 | 24 | 10 | 7 | 11 | 1 | 9 | 3 | 18 |
| 0.5 | 21 | 14 | 31 | 7 | 3 | 12 | 12 | 19 |
| 5 | 31 | 12 | 56 | 8 | 7 | 14 | 39 | 20 |
| 50 | 73 | 14 | 68 | 6 | 14 | 17 | 70 | 24 |
| 250 | 70 | 7 | 83 | 10 | 10 | 11 | 77 | 26 |
| Concentration of IFN-γ (U/mL) . | Experiment No. 1 . | Experiment No. 2 . | Experiment No. 3 . | Experiment No. 4 . | ||||
|---|---|---|---|---|---|---|---|---|
| % CD64 . | % Adhesion . | % CD64 . | % Adhesion . | % CD64 . | % Adhesion . | % CD64 . | % Adhesion . | |
| 0 | 24 | 10 | 7 | 11 | 1 | 9 | 3 | 18 |
| 0.5 | 21 | 14 | 31 | 7 | 3 | 12 | 12 | 19 |
| 5 | 31 | 12 | 56 | 8 | 7 | 14 | 39 | 20 |
| 50 | 73 | 14 | 68 | 6 | 14 | 17 | 70 | 24 |
| 250 | 70 | 7 | 83 | 10 | 10 | 11 | 77 | 26 |
In each experiment, blood PMNs from a different normal subject were incubated with IFN-γ for 24 hours at 37°C. Aliquots of the PMNs were assessed by flow cytometry for the expression of CD64 antigen and other samples applied to monolayers of untreated endothelial cells. Results are expressed as the percentage of cells expressing CD64 (% CD64) and as the percentage of PMNs adhering to endothelial monolayers (4 experiments). IFN-γ induced a dose-dependent increase in CD64 expression, but this effect was not related to an enhanced binding to untreated monolayers of endothelial cells as judged by Spearman's correlation coefficient.