The addition of L-652, 731 and L-653, 150, two synthetic PAF-specific receptor antagonists, to 72 hour cultures of phytohemagglutinin (PHA)-stimulated human peripheral blood mononuclear leukocytes (PBML) caused a dose-dependent inhibition of (3H)-thymidine incorporation into T-cells (IC50: 25 μM and 3.2 μM, respectively). This inhibition was not reversed by exogenous interleukin (IL)-1 and IL-2. PAF receptor antagonists did not affect the expression of IL-2 receptors (TAC-antigen) on T-cells. Exogenous PAF which by itself had no significant effect on PHA-stimulated PBML proliferation, only partially reversed the inhibition of proliferation caused by PAF receptor antagonists. These results may suggest the involvement of endogenously produced PAF in the regulation of immune reactions
Platelet-activating factor (PAF) receptor antagonists inhibit mitogen-induced human peripheral blood T-cell proliferation
PATRIGNANI, Paola;VALITUTTI, Salvatore;AIELLO, Francesca Bianca;MUSIANI, Piero
1987-01-01
Abstract
The addition of L-652, 731 and L-653, 150, two synthetic PAF-specific receptor antagonists, to 72 hour cultures of phytohemagglutinin (PHA)-stimulated human peripheral blood mononuclear leukocytes (PBML) caused a dose-dependent inhibition of (3H)-thymidine incorporation into T-cells (IC50: 25 μM and 3.2 μM, respectively). This inhibition was not reversed by exogenous interleukin (IL)-1 and IL-2. PAF receptor antagonists did not affect the expression of IL-2 receptors (TAC-antigen) on T-cells. Exogenous PAF which by itself had no significant effect on PHA-stimulated PBML proliferation, only partially reversed the inhibition of proliferation caused by PAF receptor antagonists. These results may suggest the involvement of endogenously produced PAF in the regulation of immune reactionsI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.