ISSN:
1365-3083
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
We studied the generation and metabolism of leukotrienes (LT) and the release of histamine by human tonsillar cell suspensions. Human tonsils were dissected and mechanically dispersed. This procedure yielded a single cell suspension with 1.6±0.5×108 cells/g tissue consisting of 97.3±0.4% lymphocytes, 1.4±0.3% granulocytes, 1.3±0.3% macrophages/monocytes, and 0.03±0.02% mast cells/basophils. The cells were stimulated either with Ca-ionophore A 23187, melittin, or anti-human IgE. Determination of the 5-Lipoxygenase products LTB4 and LTC4 was performed with specific radioimmunoassays (RIA), and histamine release was measured by the fluorophotometric technique. A time-and dose-dependent release of the mediators was monitored LTB4 exceeded the amount of LTC4 in the supernatants. The concentration of leukotrienes ranged between 0.8 and 5.4 ng LTB4/1×108 cells or 0.5 and 1.5 ng LTC4/1×108 cells, depending on the stimulus. Histamine release after stimulation ranged between 25 and 35% of the total histamine content, whereas buffer controls amounted to 17%. The incubation of the cells (1×108) with exogenously added LTB4 resulted in the formation of ω-oxidated products (20-OH and 20-COOH-LTB4) and a novel unpolar metabolite, as identified by thin layer chromatography. This metabolite was not immunoreactive in the LTB4-RIA used. LTC4 and LTD4 were converted into LTE4 when added either to sonicated cells or to the cell-free supernatants of prestimulated tonsillar cells, indicating the release of γ-glutamytranspeptidase and dipeptidase, respectively. Our data clearly demonstrate the generation and metabolism of the 54-lipoxygenase products LTB4 and LTC4 as well as the release of histamine from human dispersed tonsillar cells, suggesting that they have a modulatory function with respect to the inflammatory potential at local sites.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-3083.1988.tb02371.x
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