Pregnancy zone protein inhibits production of interleukin-2 but does not affect interleukin-2 receptor expression on T cell activation.
The effect of pregnancy zone protein (PZP), which exhibits increased levels in the blood during pregnancy, on T cells was examined. PZP was found to suppress DNA synthesis following stimulation with phytohemagglutinin (PHA), concanavalin A (ConA) or CD3 antigen or in the mixed lymphocyte reaction (MLR). This effect of PZP was mediated by a reduction in interleukin-2 (IL-2) production, and was abolished by exogenous recombinant IL-2 administration. PZP did not affect the proliferation of T cells following stimulation with the calcium ionophore A23187 and phorbol 12-myristate 13-acetate (TPA). These results suggest that PZP acts on the T cell surface and reduces IL-2 production, but not IL-2R expression, and does not directly affect Ca2+ influx or protein kinase C.
Saito
S
S
Department of Obstetrics and Gynecology, Nara Medical University, Kashihara, Japan.
Hashimoto
H
H
Yonemasu
K
K
Ichijo
M
M
D000001:Calcimycin / Q000494:pharmacology; D004247:DNA / Q000096:biosynthesis; D004591:Electrophoresis, Polyacrylamide Gel; D005786:Gene Expression Regulation; D006801:Humans; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000096:biosynthesis*; D007963:Leukocytes, Mononuclear; D008213:Lymphocyte Activation; D011257:Pregnancy Proteins / Q000494:pharmacology*; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis*; D013601:T-Lymphocytes / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D007376:Interleukin-2; D011257:Pregnancy Proteins; D015375:Receptors, Interleukin-2; D000001:Calcimycin; D004247:DNA; D013755:Tetradecanoylphorbol Acetate