Figure 2.

NGF neutralization attenuates airway hyperreactivity, airway inflammation and the T helper 2 response in asthmatic mice. Mice were sensitized via an intraperitoneal injection of 20 μg ovalbumin (OVA) and 1 mg aluminum hydroxide hydrate in 500 μl saline on days one and eight. From day 21, the mice were challenged with 5% OVA for five consecutive days. At 24 h following the last OVA challenge, mice were anesthetized and the airway responsiveness to methacholine was analyzed. (A) Changes in mice airway resistance (RL) in response to methacholine exposure. Data are expressed as a percentage above baseline (normal saline-induced RL) and presented as the mean ± standard deviation (n=7). (B) Representative photomicrographs of hematoxylin and eosin-stained lung sections from the mice (magnification, ×100). (C) Peribronchial inflammation scores of the mice; peribronchial inflammation of four mice from each group were analyzed and scored as follows: 0, normal; 1, few cells observed; 2, a ring of inflammatory cells one cell layer deep; 3, a ring of inflammatory cells 2–4 cells deep; and 4, a ring of inflammatory cells >4 cells deep. (D) Serum expression levels of IL-4 and IFN-γ in the mice were detected using an ELISA. Data are presented as the mean ± standard deviation (n=7). ^*P<0.05, vs. control group; ^▲P<0.05, vs. asthma and control IgG groups. NGF, nerve growth factor; IgG, immunoglobulin G; IFN, interferon; IL, interleukin.