Effect of fMLP treatment on the EA rosetting by neutrophils from normal donors
| Treatment . | Medium . | +anti-CD16 mAb (CLBFcgran-1) . | ||||
|---|---|---|---|---|---|---|
| 4°C . | 37°C . | fMLP . | 4°C . | 37°C . | fMLP . | |
| Donor HE | 70 | 76 | 75 | 7 | 33 | 45 |
| Donor AN | 74 | 66 | 71 | 3 | 27 | 44 |
| Donor MA | 72 | 77 | 69 | 23 | 31 | 63 |
| Donor PA | 72 | 71 | 65 | 10 | 26 | 47 |
| Donor DI | 78 | 75 | 67 | 2 | 6 | 22 |
| Treatment . | Medium . | +anti-CD16 mAb (CLBFcgran-1) . | ||||
|---|---|---|---|---|---|---|
| 4°C . | 37°C . | fMLP . | 4°C . | 37°C . | fMLP . | |
| Donor HE | 70 | 76 | 75 | 7 | 33 | 45 |
| Donor AN | 74 | 66 | 71 | 3 | 27 | 44 |
| Donor MA | 72 | 77 | 69 | 23 | 31 | 63 |
| Donor PA | 72 | 71 | 65 | 10 | 26 | 47 |
| Donor DI | 78 | 75 | 67 | 2 | 6 | 22 |
Neutrophils were incubated with fMLP (1 × 10−6mol/L) in RPMI/5 mmol/L HEPES buffer for 60 minutes at 37°C in a siliconized Eppendorf tube with occasional shaking. As a control, aliquots of cells were incubated without fMLP at 4°C and 37°C for 60 minutes. Then the cells were washed and allowed to form rosettes with EA in ice for 2 h in the presence of medium or Fab fragments of CLBFcgran-1 (final concentration, 2.5 μg/mL). The results are expressed as percentage rosetting. The addition of anti-CD16 (CLBFcgran-1 Fab) and anti-CD32A (IV.3 Fab) inhibited 98% to 100% of EA rosetting by neutrophils from all the donors tested.
EA, antibody-opsonized erythrocytes; fMLP, formyl-methionyl-leucyl-phenylalanine.