Overview of studies on cell-derived tumour necrosis factor (TNF) release as a biomarker in coal miners and controls (exposed miners)
| Cell-Type | TNF release | Primary findings | Confounders | Reference | |
| Smoking | Exposure | ||||
| PBM, 18 h | 0.75±0.14 (baseline, controls) | Priming of release; increase of coal-dust induced | No effect | No relation | 39 |
| 3.0±0.4 (LPS, 3 ng·mL−1) | TNF at early (suspect) stages of CWP | ||||
| AM, 72 h | 2.5±1.0 (spontaneous, controls) | Spontaneous release only; PMF higher than simple CWP. | No effect | NE | 40 |
| Exposed controls higher than references | |||||
| PBM, 18 h | 1.77±2.06 (baseline, controls) | TNF not related to exposure. Positive relation between profusion and TNF release within PMF group. | Minor effects | No relation | 41 |
| 9.53±7.33 (LPS, 3 ng·mL−1) | Effect of age on TNF release in retired (age >60 yrs) miners | ||||
| PBM, 18 h | 0.20±0.10 (baseline, controls) | Initial TNF‐release predictive of progression of CWP (RR=8.1 at levels greater than mean±2 sd) | Small effects | No relation | 36 |
| 2.20±0.4 (LPS, 3 ng·mL−1) | |||||
| PBM, 18 h | 0.10±0.13 (baseline,controls) | Increase of coal-induced TNF (and interleukin‐8) in miners with small or large opacities; also serum levels increased | NE | NE | [42,43 |
| Whole blood, 16 h | 0.19±0.31 (CMD, controls) | CMD‐induced TNF release significantly induced in PMF versus matched controls | No effect | No effect | 44 |
| 3.39±1.92 (LPS, 3 ng·mL−1) | Number of leukocytes increases in PMF | ||||
For comparison of studies, where possible, the unstimulated (baseline) release from cells was used for comparison
Data on TNF‐release are in ng·mL−1 from control miners and usually obtained by incubation of 5 × 105 cells
PBM: peripheral blood monocytes
AM: alveolar macrophages (from BAL)
CWP: coal workers pneumoconiosis
CMD: coal mine dust
PMF: progressive massive fibrosis
LPS: lipopolysaccharide (endotoxin)
NE : not evaluated