title: Cytotoxicity of purified listeriolysin O on mouse and human leukocytes and leukaemia cells.
abstract: BACKGROUND
  Listeriolysin O (LLO) is the main virulence factor of Listeria monocytogenes and facilitates the intracellular survival of the pathogen. Some of its characteristics endorse the growing popularity of LLO for use in biotechnology, particularly in the development of novel vaccines. Here, we evaluate the use of LLO to eradicate leukaemia cells.
  
  
  RESULTS
  A purified LLO preparation was obtained by affinity chromatography. The LLO preparation procedure was optimized and purified LLO was tested for optimal conditions of storage including temperature, application of proteinase inhibitors and serum components. We demonstrated the possibility of regulating LLO activity by adjusting cell membrane cholesterol content. The LLO preparation had haemolytic activity and had a cytotoxic effect on the human T-leukaemia Jurkat cell line as well as mouse and human peripheral blood mononuclear cells.
  
  
  CONCLUSIONS
  LLO has a very potent cytotoxic activity towards human leukocytes. Importantly, the cytotoxic activity was easily regulated in vitro and could be restricted to areas containing malignant cells, raising the possibility of future clinical application of LLO for leukaemia treatment.
authors.forename: Radosław
authors.initials: R
authors.lastname: Stachowiak
authors.forename: Marcin
authors.initials: M
authors.lastname: Łyżniak
authors.forename: Maja
authors.initials: M
authors.lastname: Grabowska
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Roeske
authors.forename: Tomasz
authors.initials: T
authors.lastname: Jagielski
authors.forename: Jacek
authors.initials: J
authors.lastname: Bielecki
authors.forename: Bożena K
authors.initials: BK
authors.lastname: Budziszewska
authors.forename: Grażyna
authors.initials: G
authors.lastname: Hoser
authors.affiliation: Medical Centre of Postgraduate Education, Marymoncka 99/103, 01-813 Warsaw, Poland. jkawiak@cmkp.edu.pl.
authors.forename: Jerzy
authors.initials: J
authors.lastname: Kawiak
mesh_terms: D000818:Animals; D001427:Bacterial Toxins / Q000302:isolation & purification / Q000494:pharmacology*; D002462:Cell Membrane / Q000737:chemistry; D002784:Cholesterol / Q000737:chemistry; D004912:Erythrocytes / Q000187:drug effects; D006360:Heat-Shock Proteins / Q000302:isolation & purification / Q000494:pharmacology*; D006460:Hemolysin Proteins / Q000302:isolation & purification / Q000494:pharmacology*; D006461:Hemolysis; D006801:Humans; D019169:Jurkat Cells; D007963:Leukocytes, Mononuclear / Q000187:drug effects*; D051379:Mice; D037521:Virulence Factors / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D001427:Bacterial Toxins; D006360:Heat-Shock Proteins; D006460:Hemolysin Proteins; D037521:Virulence Factors; D002784:Cholesterol; C038705:hlyA protein, Listeria monocytogenes