title: An updated model of cell-mediated immunity--listeriosis: clinical and research aspects.
abstract: Listeria monocytogenes causes sepsis and meningitis in immunocompromised hosts and a devastating maternal/fetal infection in pregnant women. In recent years a more benign gastroenteritis in normal hosts has been described. Listeria has been increasingly identified as a food-borne pathogen, and large-scale contamination of processed foods with resulting outbreaks has occurred in recent years, possibly as a result of consolidation of the food industry. Experimental listeriosis in mice has proven to be an extraordinarily useful model for analyzing cell-mediated immune host defenses. Contrary to original concepts, we found that neutrophils, not macrophages, are the prime effectors during early infection. CD8+ T cells are then responsible for lysing infected hepatocytes through perforin-related (early primary and secondary infection) or Fas-L/Fas mechanism (late primary). Of interest, non-classical MHC class Ib restricted recognition mechanisms exist early, whereas MHC class Ia mechanisms can be detected throughout infection.
authors.affiliation: Department of Medicine, Rhode Island Hospital, Providence 02903, USA.
authors.forename: E J
authors.initials: EJ
authors.lastname: Wing
authors.forename: S H
authors.initials: SH
authors.lastname: Gregory
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000150:complications; D000818:Animals; D017209:Apoptosis / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D004196:Disease Outbreaks; D053222:Fas Ligand Protein; D005516:Food Microbiology; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D007111:Immunity, Cellular; D016867:Immunocompromised Host; D008089:Listeria monocytogenes / Q000302:isolation & purification; D008088:Listeriosis / Q000453:epidemiology / Q000209:etiology / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000276:immunology; D051379:Mice; D009504:Neutrophils / Q000276:immunology; D054353:Perforin; D052899:Pore Forming Cytotoxic Proteins; D019014:fas Receptor / Q000276:immunology
chemical_list: C505661:FASLG protein, human; D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D008562:Membrane Glycoproteins; D052899:Pore Forming Cytotoxic Proteins; D019014:fas Receptor; D054353:Perforin