title: The early cellular response to M. leprae. An ultrastructural study.
abstract: The ultrastructural changes that develop in mouse peritoneal macrophages from 10 minutes up to 14 weeks after exposure to Mycobacterium leprae are presented. Phagocytosis occurred by a process of engulfment by cytoplasmic processes and incorporation into a phagosome, into which lysosomal enzymes were subsequently introduced. Electron transparent zones (E.T.Z.) were not observed around phagocytosed bacilli in this study, however discrete droplets of lipid-like material appeared in the cytoplasm of macrophages, between 2 and 4 weeks after ingestion of the micro-organisms. Phagosomes with double limiting membranes were observed in macrophages harvested as early as 40 minutes after exposure to M. leprae, contrary to the observations of Evans and Levy (1972).
mesh_terms: D000818:Animals; D007918:Leprosy / Q000503:physiopathology*; D008264:Macrophages / Q000382:microbiology / Q000648:ultrastructure*; D051379:Mice; D008808:Mice, Inbred CBA; D009166:Mycobacterium leprae / Q000254:growth & development*; D010587:Phagocytosis; D013997:Time Factors