Mycobacterium bovis BCG induces high mobility group box 1 protein release from monocytic cells.
High mobility group box 1 protein (HMGB-1), a nuclear protein is a critical cytokine that mediates the response to infection, injury and inflammation. The aim of our study was to elaborate a reliable in vitro model to investigate whether Mycobacterium bovis BCG is able to induce HMGB-1 secretion from the monocytic U-937 cells. Western blot technique was applied for the detection of HMGB-1 from supernatants of cells, following induction with LPS, Staphylococcus aureus, and Mycobacterium bovis BCG. HMGB-1 was subjected to MALDI-TOF mass and PSD analysis. Quantitation of the secreted HMGB-1 was performed by ELISA. The BCG strain induced higher amounts of secreted HMGB-1 than LPS or Staphylococcus aureus. The translocation of the HMGB-1 to the cytoplasm following infection of cells with BCG was demonstrated by immunofluorescence examinations.


CONCLUSIONS
Our pilot experiments draw attention the to HMGB-1-inducing ability of Mycobacterium bovis. Assessment of the pathophysiological role of this late cytokine in mycobacterial infections demands further in vitro and in vivo examinations.
Hofner
Peter
P
Department for Medical Microbiology and Immunobiology, Faculty of Medicine, University of Szeged, Dóm tér 10, H-6720 Szeged, Hungary. hofnerpeter@yahoo.com
D000595:Amino Acid Sequence; D015153:Blotting, Western; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D024243:HMGB1 Protein / Q000032:analysis / Q000378:metabolism*; D006801:Humans; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009163:Mycobacterium bovis; D021381:Protein Transport; D020298:U937 Cells
D024243:HMGB1 Protein