Effects of inhaled and subcutaneous sensitization with ovalbumin on pulmonary-function and dendritic cell distribution in guinea-pig.
Warner-TE; Millecchia-LL; Frazer-DG; Fedan-JS
J Cell Biochem Suppl 1995 Mar; 21A:32
In recent years, the relationship between airway hyper-reactivity in asthma and airway inflammation has been of interest. In this study of antigen-induced airway inflammation, we compared basal specific airway resistance (SRaw) and breathing frequency response with the distribution and prevalence of dendritic cells (DC) present within guinea pig airways following antigen sensitization and challenge with ovalbumin (OVA). Male Dunkin Hartley guinea pigs were sensitized and challenged With OVA by one of four protocols. Group A and B animals were sensitized with 1% OVA aerosol for 3 min on Day 0 and Day 7. Group A animals were challenged with 2% OVA aerosol on Day 14 for 3 min, whereas Group B animals were challenged until dyspnea occurred. Group C and D animals were sensitized by subcutaneous injection containing 10 µg OVA + 1 mg Al(OH)3 on Day 0 and Day 14. Group C was challenged on Day 21 with 2% OVA aerosol for 3 min, whereas Group D was challenged until dyspnea appeared. Controls (Group E) received saline aerosol for 3 min on Day 21. Guinea pigs were sacrificed 18 hr post-challenge. Trachea and lungs were infused with Histocon, removed and snap-frozen. Consecutive tangential sections (6µ) were incubated with monoclonal antibodies to MHC class II (C1.13.1) or tissue macrophages (MR-1) (APAAP procedure). DC were identified by positive staining with C1.13.1, negative staining with MR-1, and morphology. Immediately following OVA challenge increases in breathing frequency were seen in Groups C and D. Increases in basal SRaw were observed in Groups B and D. Groups A and E showed no significant changes in breathing frequency and SRaw. Inflammation was observed in all OVA-treated animals. DC were distributed within the lamina propria and submucosa of the trachea and in the lamina propria and adventitia of the upper bronchial regions, particularly clustering around blood vessels. No DC were found within the epithelium or in the alveolar regions. Regardless of protocol, OVA-treatment increased DC density in OVA-challenged animals. Our findings indicate that 1) OVA produced a sensitization-route dependent effect on pulmonary function and 2) all OVA treatments increased the prevalence of DC in association with inflammation.
Animals; Biological-effects; Biological-systems; Breathing; Bronchial-asthma; Cell-biology; Cell-function; Cellular-function; Cellular-reactions; Inhalation-studies; Laboratory-animals; Laboratory-testing; Pulmonary-function; Pulmonary-function-tests; Pulmonary-system; Respiratory-hypersensitivity; Respiratory-irritants
Journal of Cellular Biochemistry. Supplement