Figure 5.

Macrophages in baboon lung tissues and BALF in BPD. Relative steady-state mRNA levels of the activated macrophage marker CD68 were determined by quantitative RT-PCR using RNA obtained from total baboon lung homogenates (A) or BAL cells (B); n = 4–5 animals/group. Data are expressed as mean ± SEM from two experiments performed in triplicate. Absolute macrophage numbers were determined in BAL cell pellets of 140-d, ND, and BPD group animals (C); n = 10–12 animals/group. Immunohistochemistry was performed on paraffin-embedded lung tissue sections from 140-d (D), ND (E), and BPD (F) groups using a CD68 antibody. Methyl green was used as the counterstain. Arrowheads point to CD68-positive macrophages in representative tissue sections. Scale bar, 100 μm. *p < 0.05 versus 140 d; ^¶p < 0.05 versus ND.