Figure 6.

Cigarette smoke (CS) increases oxidative stress levels in nonhuman primate (NHP) lungs. NHPs were exposed to air or CS for up to 12 weeks. A: Thiobarbituric acid–reactive substances (TBARS, expressed as micromoles of TBARS per nanogram of protein) were measured in whole lung samples from air- and CS-exposed animals. B–D: A representative lung section immunostained for 4-hydroxynonenal (4-HNE) from NHPs exposed to CS (B and C) or air (D) for 12 weeks and the corresponding bright-field images. Intense staining for 4-HNE is detected in lung inflammatory cells (B) and lymphoid aggregates (C) in the lung of CS-exposed NHPs identified in the bright-field images. Staining for 4-HNE is detected in only a few resident lung macrophages in air-exposed NHPs. D: Green arrow indicates a 4-HNE–stained macrophage; and white arrows, 4-HNE–negative macrophages. Images shown are representative of those from four NHPs per group. E: An image of a lung section stained with a rabbit non-immune control primary antibody. Data are presented as means ± SEM (A). n = 8 air-exposed animals and n = 7 CS-exposed animals per group (A). ^∗∗P < 0.01 versus the air-exposed NHPs (A). B–E: Nuclei were counterstained with DAPI. Original magnification, ×200 (B–E). Rb, rabbit.