FIG 4.

H&E staining of tracheal tissue sections from 6- to 9-month-old baboons infected with B. pertussis. Six- to 9-month-old baboons were challenged with B. pertussis. Tracheal tissue samples were collected on days 2, 7, and 28 postchallenge, and H&E-stained slides were prepared as described in Materials and Methods. Representative images are presented. (A) Sample collected from an uninfected baboon. (B) Sample collected from a baboon at day 2 postchallenge. (C) Sample collected from a baboon at day 7 postchallenge demonstrating influx of neutrophils (red arrows) and excess mucus (black arrows) lining the mucosa. (D) Sample collected from a baboon at day 28 postchallenge. Magnifications, ×600.