التفاصيل البيبلوغرافية
| العنوان: |
The expression of functional IL-2 receptor on activated macrophages depends on the stimulus applied. |
| المؤلفون: |
Valitutti, S.1, Carbone, A.1, Castellino, F.1, N.3 Maggiano1, Ricci, R.1, Larocca, L. M.1, Musiani, P.2 |
| المصدر: |
Immunology. May89, Vol. 67 Issue 1, p44-50. 7p. |
| مصطلحات موضوعية: |
*INTERLEUKIN-2, *INTERLEUKINS, *MACROPHAGES, *PROSTAGLANDINS, *T cells, *MONOCYTES, *ELECTRON microscopy |
| مستخلص: |
Human peripheral blood monocytes (Mo) synthesize prostaglandin E2 (PGE2) when activated with lipopolysaccharide (LPS). This production is strongly enhanced by the addition of supernatant from phytohaemagglutinin (PHA)-activated T cells. To evaluate the factor(s) responsible for this enhancement we studied the effect of several cytokines on the PGE2 metabolism. Recombinant interleukin-1 (IL-1) or recombinant IL-2 strongly enhanced PGE2 synthesis in LPS-stimulated Mo cultures, whereas recombinant interferon-gamma (IFN-γ) partially inhibited its production. To see whether the effect of IL-2 on Mo was due to the presence of IL-2 receptor (IL-2R) on the cell surface, flow cytometric analysis and electron microscopy were used to investigate IL-2R expression in unstimulated and stimulated Mo. Stimulated, but not resting, Mo displayed the p55 IL-2R chain on their cellular surface and associated with the polyribosomes of the rough endoplasmic reticulum in the cytoplasm. This finding strongly suggested that the p55 chain of the IL-2R was synthesized by activated Mo. To confirm this result, 125I-labelled IL-2 was bound under high- and low-affinity conditions and cross-linked to Mo cultured in the presence of LPS, IFN-γ or IL-1. The cross-linked 125I-IL-2/IL-2R complexes were analysed by SDS-PAGE. Mo cultured with LPS, IFN-&gama; and IL-1 expressed the p55 protein detected by low-affinity cross-linking, whereas only LPS-stimulated Mo displayed a barely detectable band with an apparent MW of 70,000 under high-affinity binding conditions. In addition, stimulated Mo were found capable of producing the soluble form of IL-2R. Finally, LPS-activated Mo only responded to the addition of IL-2 by an increase in PGE2 production, suggesting that the function of IL-2R on activated Mo is linked to the stimulus applied. [ABSTRACT FROM AUTHOR] |
| قاعدة البيانات: |
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