Figure 3From: Deleted in Malignant Brain Tumors 1 (DMBT1) is present in hyaline membranes and modulates surface tension of surfactantEffects of increasing hrDMBT1 (A) and calcium (B) concentrations on surface activity of surfactant preparations. (A) Surface activity (assessed as openness of a capillary) decreased with increasing human recombinant DMBT1 concentrations (final concentrations: 0 – 330 μg/ml) in both surfactant preparations (final phospholipid concentration 1 mg/ml). 2-way-ANOVA showed a significant influence on surface tension for surfactant preparation (P = 0.0243) and for hrDMBT1 concentration (P < 0.0001) as well as an interaction between surfactant preparation and hrDMBT1 concentration (P = 0.0363). (B) Calcium chloride antagonized the decrease of surface activity in the surfactant preparations (final phospholipid concentration 1 mg/ml) induced by hrDMBT1 (final concentration: 200 μg/ml). Analysis of variance analysis stated an influence of surfactant preparation (P = 0.0004), of hrDMBT concentration (P < 0.0001) and an interaction between surfactant preparation and hrDMBT1 concentration (P = 0.0037). Note that the surface activity of Alveofact® decreased at a lower hrDMBT1 concentration than that of Curosurf® (A) and that calcium antagonized the hrDMBT1 effect at 1 mM, whereas Alveofact® required a calcium concentration >3 mM (B). Data are expressed as mean ± SEM.Back to article page