NOTCH1 and Pneumocystis infectious disease: We were unable to document changes in Notch activation related to Pneumocystis infection in this study and results therefore show that Pneumocystis associated mucus increase was not associated to changes in Notch1 pathway in the epithelium of distal airway, suggesting that the inferred transdifferentiation in Clara cell function associated to Pneumocystis was independent of Notch pathway downregulation function.