Table 1.
Cellular characteristics of induced sputum. Differential sputum cell counts are expressed as percentage of nonsquamous cells.
| Healthy controls | Severe asthmatics | Mild asthmatics | |
| Number/Sex (F) | 10 (F) | 10 (F) | 12 (F) |
| Age | 28.7 ± 6.2 | 48.6 ± 3.5 | 55.2 ± 3.2 |
| FEV1 (% predicted) | 93.2 ± 4.8 | 58.7 ± 6.2† | 87.3 ± 2.5 |
| Total cell count (106/ml) | 1.65 ± 0.7 | 3.1 ± 0.5† | 1.9 ± 0.32 |
| Macrophages (%) | 47.6 ± 5.2 | 33.6 ± 8 | 48.9 ± 4.5 |
| Neutrophils (%) | 30 ± 4.5 | 29.2 ± 4.9 | 25.7 ± 6.1 |
| Eosinophils (%) | 0.7 ± 0.2 | 5.7 ± 3.6† | 1.2 ± 0.7 |
| Lymphocytes (%) | 1.7 ± 1.2 | 6.5 ± 2† | 2.7 ± 1.8 |
| Squamous cells (%) | 4.5 ± 2 | 4.8 ± 1.9 | 4.50 ± 1.8 |
| Viability (%) | 84 ± 4 | 82 ± 6 | 87 ± 5 |
† significant differences (p < .05) compared to mild asthmatic patients and healthy controls. Successful sputum induction was achieved in 9/10 severe asthmatics and 8/12 mild asthmatics.