title: Human lymphocyte aggregation?
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.
mesh_terms: D015117:5,8,11,14-Eicosatetraynoic Acid / Q000494:pharmacology; D000328:Adult; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism / Q000494:pharmacology; D001241:Aspirin / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002449:Cell Aggregation / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D008214:Lymphocytes / Q000187:drug effects / Q000502:physiology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D013928:Thromboxane A2 / Q000494:pharmacology
chemical_list: D001095:Arachidonic Acids; D015117:5,8,11,14-Eicosatetraynoic Acid; D016718:Arachidonic Acid; D000001:Calcimycin; D013928:Thromboxane A2; D011451:Prostaglandin-Endoperoxide Synthases; D001241:Aspirin