Mediator release from basophil granulocytes in chronic myelogenous leukemia

Basophil function in patients with chronic myelogenous leukaemia

We have compared the release of histamine from basophils isolated from six patients with chronic myelogenous leukaemia (CML) and seven normal controls. No differences were noted in the release induced by rabbit anti-human IgE. However, basophils from CML patients released less than 20% of their intracellular histamine when challenged with the anaphylatoxin C5a at a concentration that caused greater than 50% release from normal basophils. Furthermore, basophils from CML donors showed a significantly lower release in the presence of the calcium ionophore A23187. These results suggest that basophils from CML patients have an inherent defect.

Human platelet stimulation by acetyl glyceryl ether phosphorylcholine

Acetyl glyceryl ether phosphorylcholine (AGEPC) induced dose-dependent platelet aggregation and release of [3H]serotonin and platelet factor 4 in citrated human platelet-rich plasma. ADP scavengers or indomethacin prevented irreversible platelet aggregation responses induced by 0.2 microM AGEPC but had no effect upon platelet secretion; prostacyclin inhibited AGEPC-induced aggregation and secretion. EDTA or EGTA inhibited AGEPC-induced aggregation but had no effect on platelet secretion.