title: Lactoferricin influences early events of Listeria monocytogenes infection in THP-1 human macrophages.
abstract: Bovine lactoferrin (BLf) and its derivative peptide lactoferricin B (LfcinB) are known for their antimicrobial activity towards several pathogens, including Listeria monocytogenes, a food-borne Gram-positive invasive bacterium that infects a wide variety of host cells, including professional phagocytes. To add further information on the antibacterial effects of these compounds, the influence of BLf, LfcinB and the antimicrobial centre of LfcinB, the hexapeptide LfcinB(4-9), on the invasive behaviour of L. monocytogenes was analysed in IFN-gamma-activated human macrophagic cells (THP-1). Significant inhibition of bacterial entry in THP-1 cells was observed at LfcinB concentrations that were unable to produce any bacteriostatic or bactericidal effect, compared with BLf and LfcinB(4-9) peptide. This inhibition occurred when LfcinB was incubated during the bacterial infection step and was not due only to competition for common glycosaminoglycan receptors. Assays performed through a temperature shift from 4 to 37 degrees C showed that inhibition of invasion took place at an early post-adsorption step, although an effect on a different step of intracellular infection could not be ruled out.
authors.affiliation: Department of Public Health Sciences, University 'La Sapienza', P.le A. Moro 5, 00185 Rome, Italy 2Biology Department, University of Rome Tre, V.le Marconi 446, 00146 Rome, Italy 3Laboratory of Ultrastructure, Istituto Superiore di Sanità, V.le Regina Elena 299, 00161 Rome, Italy.
authors.forename: Catia
authors.initials: C
authors.lastname: Longhi
authors.affiliation: Department of Public Health Sciences, University 'La Sapienza', P.le A. Moro 5, 00185 Rome, Italy 2Biology Department, University of Rome Tre, V.le Marconi 446, 00146 Rome, Italy 3Laboratory of Ultrastructure, Istituto Superiore di Sanità, V.le Regina Elena 299, 00161 Rome, Italy.
authors.forename: Maria P
authors.initials: MP
authors.lastname: Conte
authors.affiliation: Department of Public Health Sciences, University 'La Sapienza', P.le A. Moro 5, 00185 Rome, Italy 2Biology Department, University of Rome Tre, V.le Marconi 446, 00146 Rome, Italy 3Laboratory of Ultrastructure, Istituto Superiore di Sanità, V.le Regina Elena 299, 00161 Rome, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Penta
authors.affiliation: Department of Public Health Sciences, University 'La Sapienza', P.le A. Moro 5, 00185 Rome, Italy 2Biology Department, University of Rome Tre, V.le Marconi 446, 00146 Rome, Italy 3Laboratory of Ultrastructure, Istituto Superiore di Sanità, V.le Regina Elena 299, 00161 Rome, Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Cossu
authors.affiliation: Department of Public Health Sciences, University 'La Sapienza', P.le A. Moro 5, 00185 Rome, Italy 2Biology Department, University of Rome Tre, V.le Marconi 446, 00146 Rome, Italy 3Laboratory of Ultrastructure, Istituto Superiore di Sanità, V.le Regina Elena 299, 00161 Rome, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Antonini
authors.affiliation: Department of Public Health Sciences, University 'La Sapienza', P.le A. Moro 5, 00185 Rome, Italy 2Biology Department, University of Rome Tre, V.le Marconi 446, 00146 Rome, Italy 3Laboratory of Ultrastructure, Istituto Superiore di Sanità, V.le Regina Elena 299, 00161 Rome, Italy.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Superti
authors.affiliation: Department of Public Health Sciences, University 'La Sapienza', P.le A. Moro 5, 00185 Rome, Italy 2Biology Department, University of Rome Tre, V.le Marconi 446, 00146 Rome, Italy 3Laboratory of Ultrastructure, Istituto Superiore di Sanità, V.le Regina Elena 299, 00161 Rome, Italy.
authors.forename: Lucilla
authors.initials: L
authors.lastname: Seganti
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002417:Cattle; D002460:Cell Line; D006801:Humans; D007231:Infant, Newborn; D007781:Lactoferrin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D008089:Listeria monocytogenes / Q000187:drug effects* / Q000472:pathogenicity*; D008088:Listeriosis / Q000382:microbiology; D008264:Macrophages / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D010455:Peptides / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D010455:Peptides; C082171:lactoferricin B; D007781:Lactoferrin