Fig. 3

Interactions of M. abscessus with epithelial cells in the infected PCLS. a–c M. abscessus, stained in pink, can be found isolated or forming aggregates in the alveolar space; mycobacteria can be observed interacting directly with type I pneumocytes (NI), type II pneumocytes (N-II), neutrophils (N), lymphocytes (L), and foamy macrophages (FM), some of which demonstrate karyorrhexis (M*); in addition, cell detritus with nuclear fragments are observed (dotted area in c). d A cluster of foamy macrophages (dotted area), some of which show nuclear pyknosis (P); mycobacterial fragments are identified with arrows. e, f Multinucleated giant cell (MGC) interacting with mycobacteria (arrows). ZN staining (×40). Total magnification