Expression des SOCS-1 et SOCS-3 par les lymphocytes T humains en réponse à des cytokines immuno-modulatrices
Cytokines regulate fundamental biological processes via the JAK-STAT signaling pathway. Suppressors of Cytokine Signaling proteins (SOCS), intracellular proteins, inhibit the JAK-STAT pathway. Emerging evidence supports the involvement of SOCS in diseases of the immune system but no data is available regarding their expression in human T cells. We postulate that the cytokines Interferon-β (IFN-β) and Interleukin-27 (IL-27), both potential immuno-regulators, have beneficial roles through the induction of SOCS proteins. The impact of IFN-β and IL-27 on the SOCS-1 and SOCS-3 expression by human CD4 and CD8 T cells was assessed using peripheral blood mononuclear cells from healthy donors. We evaluated the expression of SOCS-1 and SOCS-3 at the mRNA level by qRTPCR and at the protein level by immunocytochemistry. A rapid increase of SOCS-1 and SOCS-3 mRNA levels was observed upon cytokine addition, and such upregulation was confirmed at the protein level. To mimic patients under IFN-β treatment, both T cell subsets were chronically exposed to IFN-β. We observed an increase of SOCS-1 after each stimulation but not for SOCS-3. IL-27 stimulation increased SOCS-1 and SOCS-3 mRNA levels in CD8 T cells but only slightly in CD4 T cells; these observations correlate with previous observations in our laboratory showing less IL-27 receptors on CD4 T cells than CD8 counterparts. Our project determined the distinct expression of SOCS proteins in different human T cells subsets. This study could highlight the mechanism of action of cytokines such as IFN-β and IL-27.
SOCS-1 SOCS-3 lymphocytes T CD8 SOCS-1 SOCS-3 CD8 T lymphocytes CD4 T lymphocytes Interferon-beta Interleukin-27 Multiple sclerosis