title: Effect of Escherichia coli L-form cytoplasmic membranes on the interaction between macrophages and Lewis lung carcinoma cells: scanning electron microscopy.
abstract: Scanning electron microscopy (SEM) investigations on the interactions between peritoneal macrophages from Lewis lung carcinoma (LLC)-bearing mice and LLC tumour cells during 21 days after tumour implantation were carried out. The action of lipopolysaccharide (LPS)-containing cytoplasmic membranes (CM), from the stable protoplast type L-form of Escherichia coli, on the activity of in vitro phagocytosis was studied; CM induced a continuous increase in macrophage numbers. Activation of macrophage surfaces in healthy and tumour-bearing mice was established. Lamelipods, pseudopods and migration fringes 14 days after CM application were seen. Crater-like cavities deeply in the macrophage cells as well as adherent or prominent engulfed tumour cells within macrophages were observed during in vitro interaction with LLC cells. Macrophages from tumour-bearing mice without CM treatment showed less activation evaluated by SEM during earlier stages of tumour growth. The SEM investigation proved the temporary stimulating effect of E. coli L-form CM on the cell surface activation of peritoneal macrophages in healthy and LLC-bearing mice.
authors.affiliation: Institute of Microbiology, Bulgarian Academy of Sciences, Sofia.
authors.forename: E H
authors.initials: EH
authors.lastname: Ivanova
authors.forename: L
authors.initials: L
authors.lastname: Michailova
authors.forename: Z
authors.initials: Z
authors.lastname: Stefanova
authors.forename: H
authors.initials: H
authors.lastname: Neychev
authors.forename: S
authors.initials: S
authors.lastname: Radoevska
authors.forename: J
authors.initials: J
authors.lastname: Gumpert
mesh_terms: D000818:Animals; D018827:Carcinoma, Lewis Lung / Q000276:immunology / Q000382:microbiology* / Q000473:pathology; D002448:Cell Adhesion / Q000276:immunology; D002462:Cell Membrane / Q000276:immunology / Q000382:microbiology; D002478:Cells, Cultured; D003593:Cytoplasm / Q000276:immunology* / Q000382:microbiology; D004926:Escherichia coli / Q000276:immunology* / Q000648:ultrastructure; D007740:L Forms / Q000276:immunology* / Q000648:ultrastructure; D017737:Macrophages, Peritoneal / Q000276:immunology* / Q000382:microbiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008855:Microscopy, Electron, Scanning; D010587:Phagocytosis / Q000276:immunology*