Fig. 4

Tetracycline reduces lung injury in silica exposed mice. C57BL/6 J mice were challenged with silica (SIL) and treated with tetracycline (TET) as described in Fig. 3. Total protein (A), albumin (B), neutrophils (C), macrophages (D) and lymphocytes (E) were quantified in bronchoalveolar lavage fluid by BCA, ELISA and flow cytometry (n ≥ 6 per group). Lungs were removed at 24 h and stained with H&E. Representative histologic sections are shown (magnification, 20×) and lung injury score was determined by examining 5 sections/lung/animal (n = 4 per group, magnification × 100) (D). Median with interquartile range of ≥ 3 independent experiments, (SIL + TET (n = 6) vs. SIL + PBS (n = 6)) (PBS + PBS (n = 6)), Mann–Whitney Test