Hydrogen peroxide mediated killing of bacteria

摘要: Polymorphonuclear leukocytes (PMN) or neutrophils have multiple systems available for killing ingested bacteria. Nearly each of these incorporates H2O2 indicating the essential nature this reactive oxygen intermediate microbicidal activity. Following ingestion bacteria by PMN, is formed respiratory burst which consumes O2 and generates from .-. deposited intracellularly near within phagocytic vacuoles where it can react with MPO-H2O2-halide system to form toxic hyperchlorous acid (HOCl) and/or possibly singlet (1O2). also .- iron (Fe++) lactoferrin highly hydroxyl radical (.OH). These mechanisms appear important since deficiencies production, myeloperoxidase frequently increases their owner's susceptibility infection. In particular, examination PMN infection prone patients chronic granulomatous disease (CGD) most clearly demonstrates importance in CGD lack capacity effectively generate subsequently impaired ability kill catalase positive (H2O2 producing) but not negative (not glutathione peroxidase cytoplasms protect themselves toxicity H2O2. Finally, while critical host defense, be released extracellularly thereby play a significant role mediated tissue injury.