Some white blood cells kill invaders in quite a different way than immunologists had thought, research in this week's Nature (Vol. 416, No. 6878, 21 Mar 2002) suggests.
Neutrophils are granular white blood cells. The textbooks say that they destroy infectious agents by engulfing them, releasing toxic superoxide (O2-) into the vesicle containing the ingested microbe, and then gassing them. A new study of mouse neutrophils killing Staphylococcus aureus bacteria suggests that the mechanism may be rather different. As the neutrophils produce enormously high levels of superoxide they also pump large amounts of potassium ions into the in the vesicle. This creates the high pH that is optimal for the release of granule enzymes to complete the destruction of the microbe, argue Anthony W. Segal of University College London and colleagues. CONTACT: Anthony Segal tel +44 20 7679 6175 e-mail t.segal@ucl.ac.uk (C) Nature press release.
Message posted by: Trevor M. D'Souza
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