The Journal of Immunology, Vol 141, Issue 4 1307-1310, Copyright © 1988 by American Association of Immunologists

ARTICLES

Histamine release from human basophils by synthetic block co-polymers composed of polyoxyethylene and polyoxypropylene and synergy with immunologic and non-immunologic stimuli

TP Atkinson, TF Smith and RL Hunter
Department of Pathology, Emory University School of Medicine, Atlanta, GA 30322.

Co-polymers composed of polyoxyethylene and polyoxypropylene have been shown previously to trigger histamine release from mouse peritoneal mast cells; this property quantitatively is directly related to the ionophorous ability of these compounds to cause a functional exchange of intracellular K+ for extracellular Na+ across the cell membrane. We investigated the effect of an inflammatory copolymer, T130R2, on human basophils. The data demonstrate that T130R2 can cause calcium-dependent histamine release from human basophils in vitro. Further, at concentrations that do not cause histamine release, this co-polymer markedly augments release by suboptimal concentrations of the lectin Con A or anti-IgE antibody and the phorbol ester 12-O-tetradecanoyl- phorbol-13-acetate but not the calcium ionophore A23187. Thus, these co- polymers induce mediator release from cells of both rodents and humans. In both instances it is likely that calcium-dependent cell triggering is the result of an influx of sodium ions with concomitant depolarization of the transmembrane potential. In common with the calcium ionophore A23187, the co-polymer T130R2 has the ability to synergize with stimuli which trigger the IgE receptor as well as those which directly activate the cellular calcium- and phospholipid- dependent protein kinase.