Figure 4.

Following allergic challenge of sensitized C57BL/6 mice there was a significantly increased production of SP-D in the lung in comparison with similarly treated Balb/c mice. Western blot of three representative SP-D samples from the SA surfactant fraction of the BAL fluid of Balb/c and C57BL/6 mice (A). Nitrocellulose blots with samples of SA surfactant from BAL naïve and sensitized mice were probed with polyclonal antisera against SP-D antibody as described. Each lane contains 10 μg total protein. The relative content of SP-D bands in each sample was determined by densitometric scanning of the 43-kD bands from multiple blots and quantified as described (B). Open bars: Naive mice; Closed bars: Sensitized mice. Data are expressed as % of naïve controls levels. N = 3–5 samples were used in each group. Mean ± SEM was calculated after deriving the average of the results from two independent experiments. *p < 0.05 Sensitized vs Naive; #p < 0.05 C57BL/6 vs Balb/c. Autoradiographs of three representative SP-D mRNA samples of Balb/c and C57BL/6 mice (C). Total RNA for northern blot analysis was prepared from the lungs of naïve and sensitized mice as described. Intensity was quantified by densitometric scanning and values were normalized to 28S mRNA (D). Intensity of 28S band was similar in each sample (data not shown). SP-D mRNA content is expressed as % of naïve Balb/c level. Open bars: Naive mice; Closed bars: Sensitized mice. N = 7–8 samples were used. Mean ± SEM was calculated after deriving the average of the results from two independent experiments.