Neutrophil activation by surface bound IgG: pertussis toxin insensitive activation

Surface bound IgG induces neutrophil degranulation and production of superoxide radicals by a mechanism that is not inhibited by either pertussis toxin or cholera toxin, whereas these functions induced by soluble mediators such as FMLP and soluble aggregates of IgG are profoundly inhibited by pertussis toxin. Interaction of neutrophils with surface bound IgG triggers the loss of 32P labeled PIP2 and PIP and the influx of extracellular calcium. Neither of these cellular events when induced by surface bound IgG is inhibited by pertussis toxin. These observations suggest that neutrophil activation induced by surface bound IgG proceeds along a pathway which is not regulated by proteins which are inhibited by either pertussis or cholera toxins.