MYD88 and Klebsiella pneumonia: However, our first preliminary results with mice generated from intercrossings of Myd88fl/fl mice and mice with Cre recombinase controlled by the surfactant protein C promoter [51], resulting in mice with a targeted deletion of Myd88 in distal airway epithelium, suggest that epithelial cell MyD88 does not contribute to protective immunity during Klebsiella pneumonia.