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PubMed · 6436835

Human lymphocyte aggregation?

M A Lazzari·M A Schattner·M Finiasz·M Gimeno
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Abstract

The purpose of the present study was to assess lymphocyte (L) aggregation. Mononuclear cells were obtained according to Boÿum. Blood was defibrinated with glass beads and laid on Ficoll-Hypaque gradients. Monocyte depletion was achieved by adherence to plastic for 18 hs. L aggregation was assayed using the turbidimetric method. When L were challenged with collagen (1-8 micrograms/ml), ADP (2.5 microM), epinephrine (1 X 10(-4) M), ristocetin (1.5 mg/ml) and bovine F VIII no aggregation could be observed. When L were stimulated by arachidonic acid (AA) (160 microM) a complete and irreversible aggregation was obtained. This effect was markedly inhibited when L were previously incubated with aspirin (40 micrograms/ml). On the other hand 5, 8, 11, 14 eicosatetraynoic acid (ETYA), a lypoxygenase inhibitor, was not able to reverse L aggregation induced by AA. Leukotriene B4, C4 and D4 were not able to induce L aggregation. When TXA2 like material from platelets and L was transferred to L preincubated with aspirin a normal aggregation response was obtained. All these results lead to the concept that the main pathway involved in L AA metabolism is probably cyclo-oxygenase. Ionophore A 23187 was not able to induce L aggregation at any concentration employed (0.1 - 100 microM) and 6 keto PGE1 could not inhibit AA induced lymphocyte aggregation.

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5,8,11,14-Eicosatetraynoic AcidAdultArachidonic AcidArachidonic AcidsAspirinCalcimycinCell AggregationHumansIn Vitro TechniquesLymphocytesProstaglandin-Endoperoxide SynthasesThromboxane A2Comparative StudyJournal Article

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BibTeXRIS

M A Lazzari, M A Schattner, M Finiasz, M Gimeno. 1984. Human lymphocyte aggregation?. https://doi.org/10.1016/0262-1746(84)90130-6

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