Neutrophil derived interference in the fluorometric determination of histamine.
Siegel-PD; Lewis-DM; Olenchock-SA
Int Arch Allergy Appl Immunol 1990 Sep; 93(1):80-82
Possible neutrophil derived interferences in the fluorometric determination of histamine (51456) were examined. Leukocytes prepared from venous blood samples drawn from two volunteers were incubated alone or with opsonized zymogen for 1 hour at 37 degrees-C to stimulate the neutrophils. The samples were centrifuged and the supernatant recovered. Histamine in the supernatant was extracted and derivatized by treatment with o-phthalaldehyde (OPD) in methanol and sodium-hydroxide. The samples were analyzed for histamine by simple fluorometry. The authenticity of the histamine like fluorescence was checked by treating some of the samples with diamine-oxidase before fluorometric analysis. The apparent histamine content of the zymogen stimulated samples expressed as the percentage histamine release minus the percentage basal release was 14 and 11%. The percentage histamine release of the samples after treatment with diamine-oxidase was 5 and 10%, respectively. Dextran gradient separated cell preparations containing 10(6) to 10(7) neutrophils per milliliter demonstrated an apparent histamine release of 5 to 12%. The histamine/OPD derivative was isolated from zymogen stimulated and untreated leukocyte cultures and analyzed by high performance liquid chromatography with fluorescence analysis. Extraneous elution peaks that were highly fluorescent were observed in the zymogen stimulated cultures, but not in the unstimulated cultures. The authors conclude that during the fluorometric analysis of histamine in supernatants containing zymogen stimulated neutrophils, the neutrophils apparently produce a factor that creates a positive interference.
NIOSH-Author; Analytical-methods; Blood-cells; Fluorescence-spectrometry; Sample-preparation; Immunology; Amines; Chromatographic-analysis
International Archives of Allergy and Applied Immunology