PAI-1 mRNA protein expression in lungs. (A) PAI-1 protein concentrations in lung homogenates measured 48 hours after intranasal administration of sterile saline (control) or S pneumoniae (pneumonia). Data are mean ± SE; n = 8 for each group. ^*P < .05 versus control. (B) Localization of PAI-1 mRNA in lungs by in situ hybridization, 48 hours after intranasal inoculation with sterile saline (i) or S pneumoniae (ii). Slides are representative of n = 8 mice. Magnification, × 55.