DEUTERIUM-OXIDE-INDUCED HISTAMINE-RELEASE FROM BASOPHILS OF ALLERGIC SUBJECTS .1. RESPONSIVENESS TO DEUTERIUM-OXIDE REQUIRES AN ACTIVATION STEP

  • 1 January 1984
    • journal article
    • research article
    • Vol. 129  (4) , 592-596
Abstract
Basophils from many atopic persons, and especially asthmatic patients, release histamine in response to 44% deuterium oxide (D2O) while basophils from nonatopic persons do not release histamine. The present experiments analyzed the mechanisms by which D2O mediated release. Although D2O induced release from washed leukocytes, it failed to induce release from whole blood or from leukocytes that sedimented but were not washed. The kinetics of release after washing were rapid and were equivalent regardless of the temperature at which cells were sedimented (0.degree. or 37.degree. C). Washed cells became desensitized to the action of D2O within 30 to 60 min at 37.degree. C; unwashed leukocytes did not become desensitized. Serum or plasma inhibited D2O-induced release although high concentrations (1/5) were less inhibitory than lower ones (1/10 to 1/100). Basophils from D2O responders also released histamine in response to a platelet enhancing factor (PEF) while those from D2O nonresponders did not. As with D2O-mediated release, PEF-mediated release occurred only with washed leukocytes, desensitized within 30 to 60 min at 37.degree. C and was inhibited by serum. Evidently, D2O induces histamine release by augmenting the effects of an endogenous activation mechanism, and PEF acts on the same (D2O-responsive) donors to augment this activation mechanism. Cell activation, as well as desensitization of this activation mechanism, occurs rapildy when basophils are washed free of plasma inhibitors and placed at 37.degree. C.