CXCR2 and anaphylaxis: Guinea pigs were passively sensitized by anti-ovalbumin rabbit serum and 24 h later their hearts were excised and isolated and anaphylactic challenge was induced by a bolus injection of ovalbumin showing possible involvement of platelet activating factor (PAF) in anaphylaxis (32) while mice were sensitized to hazelnut and after repeated oral allergen challenge expansion of cardiac mastcells in the pericardium and myocardium was shown and IL-6 and CCR1/3 and CXCR2 signaling chemokines were significantly elevated (33).