BALB/c mice (6–8 http://www.selleckchem.com/products/BIBW2992.html weeks), free of specific pathogens, were maintained in individually ventilated cages, housed in autoclaved cages and fed on OVA-free diets, in an

air-conditioned room on a 12 h light/dark cycle. Sterile special processing forage and water were provided adequately. Cages, bedding, food, and water were sterilized before use. Pregnant mice went into labor on 20 day of pregnancy and newborn mice were raised and maintained in the same conditions. Mice were divided into the following groups: (1) sensitizations and challenges with ovalbumin (OVA group); (2) treatment with PCV7 immunization in infant, sensitizations and challenges with OVA in adult (PCV7 + OVA group); (3) the control group. On day 21, mice in the PCV7 + OVA group were administered 7-valent pneumococcal conjugate vaccine (PCV7, Wyeth, USA) 33 μl intranasally every 12 h for

three doses [8]. The mice in the OVA and PCV7 + OVA groups were sensitized intraperitoneally with 100 μg ovalbumin (OVA, Sigma) diluted in 50% aluminum hydroxide (Pierce) to a total volume of 200 μl on day 28 and day 42. From day 49 to 52, the mice were challenged with OVA aerosolized for 30 min every day lasting for 4 days. The control group mice were sensitized and challenged with GSK1349572 sterile PBS at the same time. AAD was assessed 24 h after the final challenge. In our experiment, each experiment was repeated three times. Two to three mice were used in every experimental test described hereafter. This study was approved by the Institutional Animal Care and Research Advisory Committee at the Chongqing Medical University. All experimental animals were used in accordance however with the guidelines issued by the Chinese Council on Animal Care. AHR was assessed in vivo by measuring changes in transpulmonary

resistance using a mouse plethysmograph and methods similar to those previously described [12]. Briefly, 24 h after the final challenge, AHR was assessed in conscious, unrestrained mice by means of whole-body plethysmography (Emca instrument; Allmedicus, France). Each mouse was placed into a plastic chamber and exposed to aerosolized PBS followed by increasing concentrations of an aerosolized methacholine (Sigma-Aldrich, St. Louis, Mo. USA) solution (3.125, 6.25, 12.5, 25, and 50 mg/ml; Sigma) in PBS for 3 min exposures and then the mice had a rest for 2 min, after which a computer program was used to calculate Penh from the continuously recorded pressure and flow data for 5 min. Then take the average of the 5 min records as the value of Penh of this concentration. Penh is a dimensionless value and correlates with pulmonary airflow resistance. It represents a function of the ratio of peak expiratory flow to peak inspiratory flow and a function of the timing of expiration. After formalin fixation, the left lung was dissected and embedded in paraffin. Sections of 4 μm thickness were cut and stained with hematoxylin and eosin (H&E; Sigma).