Fig. 3

The inflammatory pathological changes of the CAP-AB infected mice were significantly more severe than the HAP-AB group. Pulmonary pathology of CAP-AB YC128 and HAP-AB YC156 group mice. a 24 h after YC156 inoculation. Moderate edema in pulmonary interval (red arrow), some lymphocytes and neutrophils invasion (black arrow). b 48 h after YC156 inoculation. Focal infiltration of lymphocytes and neutrophils in bronchial epithelium (black arrow), protein effusion with inflammatory cell infiltration in some alveolus (red arrow). c 72 h after YC156 inoculation, some of the alveolus atrophy and lung consolidation (black arrow), focal intra alveolar hemorrhage (red arrow). d 24 h after YC128 inoculation. Most alveoli atrophy, lung consolidation (black arrow), the alveoli fused into large alveoli (red arrow). e 48 h after YC128 inoculation. Lung consolidation, destruction of alveolus, mononuclear and neutrophils invasion (black arrow), some alveolis fused into large alveoli (red arrow). f 72 h after YC128 inoculation. Lung consolidation, destruction of alveolus (black arrow) with a large number of mononuclear, lymphocytes and neutrophils invasion (red arrow)