Figure 6

Immunohistochemical analysis of ChaFF protein expression in the lungs of Nb, Pcc and co-infected mice. Protein expression in lung sections corroborated BALF concentrations of ChaFF proteins observed around 7 days pi, as illustrated by days 5 and 7 pi staining intensity scores for RELMα (A) and Ym1 (B) as well as representative micrographs (at increasing magnification) of day 7 pi slides stained for RELMα (C). Down-regulation of ChaFFs was observed in co-infected mice (Nb+Pcc) compared to Nb mice; differences were significant for both RELMα and Ym1 at 5 days pi (RELMα P = 0.0056 and Ym1 P = 0.0153) and for Ym1 at 7 days pi (P = 0.0171). Scores were obtained by analyzing bronchial epithelium in ten fields per mouse using a scoring system described in Methods. The whisker-and-box graphs with minimum and maximum values depict results from a representative experiment with 4-9 mice per group. The symbol ¶ indicates significance of the difference between co-infected and Nb mice (P values included above and in Results text).