Enterobacter cloacae leukotoxin: modulation of reactive oxidant species generated by neutrophils

BARNES AI, PARAJE MG, ORSILLES M, ALBESA I.

LUMINESCENCE : THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE.

JOHN WILEY & SONS LTD

Lugar: LOndres; Año: 2001 vol. 16 p. 33 - 38

1522-7235

A leukotoxin purified from Enterobacter cloacae culture by saline precipitation, gel chromatography and HPLC was studied as a modulator of reactive oxidant species (ROS) produced by human neutrophils. Chemiluminescence showed that stimulation of ROS was achieved at a low leukotoxin concentration, but ROS production decreased when the toxin was applied at concentrations above 30 microg/mL. Also, the addition of 100 microg toxin/mL significantly reduced the activating effect of phorbol myristate acetate (PMA) and low doses of toxin did not produce an opposite effect toward the stimulation produced by PMA. Normal neutrophils showed a linear correlation between the inverse of ROS production and time, but the kinetic reaction changed when toxins were added to the cells and the ROS formation increased directly with time.