HIV-1 transactivator protein induction of suppressor of cytokine signaling-2 contributes to dysregulation of IFNγ signaling

Blood ◽  
2009 ◽  
Vol 113 (21) ◽  
pp. 5192-5201 ◽  
Author(s):  
Sherman M. Cheng ◽  
James C. B. Li ◽  
San San Lin ◽  
Davy C. W. Lee ◽  
Li Liu ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Interferon Γ ◽  
Cytokine Signaling ◽  
Blood Monocytes ◽  
Suppressor Of Cytokine Signaling ◽  
Dependent Inhibition ◽  
Receptor Signaling Pathway ◽  
Transactivator Protein ◽  
Hiv 1

AbstractHIV infection remains a worldwide threat. HIV-1 transactivator protein Tat is one of the retroviral proteins identified as a key immunomodulator in AIDS pathogenesis. Although the primary function of Tat is to regulate HIV-1 replication in the infected cell, it also dysregulates cytokine production resulting in perturbation of the host immune response and enhancement of the retrovirus survival. Because interferon-γ (IFNγ) is a pleiotropic cytokine with potent antiviral and immunoregulatory effects, we investigated whether Tat interferes with the IFNγ signal transduction in primary monocytes. We demonstrated that Tat impaired the IFNγ-receptor signaling pathway at the level of STAT1 activation, possibly via Tat-dependent induction of suppressor of cytokine signaling-2 (SOCS-2) activity. We delineated the inhibitory role of SOCS-2 in IFNγ signaling pathway by overexpression of exogenous SOCS-2 in HEK293 cell. The results showed that SOCS-2 suppressed the IFNγ-activated STAT1 phosphorylation and consequent IFNγ-regulated transcription of specific genes. To confirm the role of SOCS2 in the Tat-induced process, we demonstrated that SOCS-2 siRNA in human blood monocytes abrogated the Tat-dependent inhibition of IFNγ signaling. Our data suggested a possible mechanism implicating the role of SOCS-2 in mediating HIV-1–induced immune evasion and dysregulation of IFNγ signaling in primary human monocytes.

scholarly journals The role of CXC-chemokine receptor CXCR2 and suppressor of cytokine signaling-3 (SOCS-3) in renal cell carcinoma

BMC Cancer ◽  
2014 ◽  
Vol 14 (1) ◽  
Author(s):  
Anastasios Stofas ◽  
Georgia Levidou ◽  
Christina Piperi ◽  
Christos Adamopoulos ◽  
Georgia Dalagiorgou ◽  
...  
Keyword(s):  
Renal Cell Carcinoma ◽  
Cell Carcinoma ◽  
Chemokine Receptor ◽  
Renal Cell ◽  
Cytokine Signaling ◽  
Suppressor Of Cytokine Signaling ◽  
Cxc Chemokine ◽  
Chemokine Receptor Cxcr2

Silver nanoparticles Induce Anti-Proliferative Effects on Airway Smooth Muscle Cells. Role of Nitric Oxide and Muscarinic Receptor Signaling Pathway

2013 ◽  
Vol 65 ◽  
pp. S104
Author(s):  
Manuel Alejandro Ramirez-Lee ◽  
Hector Rosas-Hernandez ◽  
Samuel Salazar-Garcia ◽  
Jose Manuel Gutiérrez-Hernández ◽  
Ricardo Espinosa- Tanguma ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Silver Nanoparticles ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Signaling Pathway ◽  
Muscarinic Receptor ◽  
Airway Smooth Muscle ◽  
Airway Smooth Muscle Cells ◽  
Receptor Signaling Pathway

Role of Suppressor of Cytokine Signaling 2 during the development and resolution of an experimental arthritis

2022 ◽  
pp. 104476
Author(s):  
Allysson Cramer ◽  
Izabela Galvão ◽  
Nathália Venturini de Sá ◽  
Paulo Gaio ◽  
Natália Fernanda de Melo Oliveira ◽  
...  
Keyword(s):  
Experimental Arthritis ◽  
Cytokine Signaling ◽  
Suppressor Of Cytokine Signaling

Abstract 3691: Deletion of Suppressor Of Cytokine Signaling-1 in a Murine Model of Atherosclerosis Results in a Lethal Systemic Inflammation

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Christina Grothusen ◽  
Harald Schuett ◽  
Stefan Lumpe ◽  
Andre Bleich ◽  
Silke Glage ◽  
...  
Keyword(s):  
Foam Cell ◽  
Low Density Lipoprotein ◽  
Cell Formation ◽  
Density Lipoprotein ◽  
Foam Cell Formation ◽  
Cytokine Signaling ◽  
Suppressor Of Cytokine Signaling ◽  
The Impact

Introduction: Atherosclerosis is a chronic inflammatory disease of the cardiovascular system which may result in myocardial infarction and sudden cardiac death. While the role of pro-inflammatory signaling pathways in atherogenesis has been well characterized, the impact of their negative regulators, e.g. suppressor of cytokine signaling (SOCS)-1 remains to be elucidated. Deficiency of SOCS-1 leads to death 3 weeks post-partum due to an overwhelming inflammation caused by an uncontrolled signalling of interferon-gamma (IFNγ). This phenotype can be rescued by generating recombination activating gene (rag)-2, SOCS-1 double knock out (KO) mice lacking mature lymphocytes, the major source of IFNγ. Since the role of SOCS-1 during atherogenesis is unknown, we investigated the impact of a systemic SOCS-1 deficiency in the low-density lipoprotein receptor (ldlr) KO model of atherosclerosis. Material and Methods: socs-1 −/− /rag-2 −/− deficient mice were crossed with ldlr-KO animals. Mice were kept under sterile conditions on a normal chow diet. For in-vitro analyses, murine socs-1 −/− macrophages were stimulated with native low density lipoprotein (nLDL) or oxidized (ox)LDL. SOCS-1 expression was determined by quantitative PCR and western blot. Foam cell formation was determined by Oil red O staining. Results: socs-1 −/− /rag-2 −/− /ldlr −/− mice were born according to mendelian law. Tripel-KO mice showed a reduced weight and size, were more sensitive to bacterial infections and died within 120 days (N=17). Histological analyses revealed a systemic, necrotic, inflammation in Tripel-KO mice. All other genotypes developed no phenotype. In-vitro observations revealed that SOCS-1 mRNA and protein is upregulated in response to stimulation with oxLDL but not with nLDL. Foam cell formation of socs-1 −/− macrophages was increased compared to controls. Conclusion: SOCS-1 seemingly controls critical steps of atherogenesis by modulating foam cell formation in response to stimulation with oxLDL. SOCS-1 deficiency in the ldlr-KO mouse leads to a lethal inflammation. These observations suggest a critical role for SOCS-1 in the regulation of early inflammatory responses in atherogenesis.

scholarly journals miR-221 and miR-155 regulate human dendritic cell development, apoptosis, and IL-12 production through targeting of p27kip1, KPC1, and SOCS-1

Blood ◽  
2011 ◽  
Vol 117 (16) ◽  
pp. 4293-4303 ◽  
Author(s):  
Changming Lu ◽  
Xin Huang ◽  
Xiaoxiao Zhang ◽  
Kristin Roensch ◽  
Qing Cao ◽  
...  
Keyword(s):  
Cytokine Signaling ◽  
Wild Type ◽  
Suppressor Of Cytokine Signaling ◽  
Hematopoietic Progenitor ◽  
Monocyte Differentiation ◽  
P27kip1 Protein ◽  
And Function ◽  
Antigen Presenting ◽  
Dc Maturation

Abstract Dendritic cells (DCs) are potent antigen-presenting cells derived from hematopoietic progenitor cells and circulating monocytes. To investigate the role of microRNAs (miRNAs) during DC differentiation, maturation, and function, we profiled miRNA expression in human monocytes, immature DCs (imDCs), and mature DCs (mDCs). Stage-specific, differential expression of 27 miRNAs was found during monocyte differentiation into imDCs and mDCs. Among them, decreased miR-221 and increased miR-155 expression correlated with p27kip1 accumulation in DCs. Silencing of miR-221 or overexpressing of miR-155 in DCs resulted in p27kip1 protein increase and DC apoptosis. Moreover, mDCs from miR-155−/− mice were less apoptotic than those from wild-type mice. Silencing of miR-155 expression had little effect on DC maturation but reduced IL-12p70 production, whereas miR-155 overexpression in mDCs enhanced IL-12p70 production. Kip1 ubiquitination-promoting complex 1, suppressor of cytokine signaling 1, and CD115 (M-CSFR) were functional targets of miR-155. Furthermore, we provide evidence that miR-155 indirectly regulated p27kip1 protein level by targeting Kip1 ubiquitination-promoting complex 1. Thus, our study uncovered miRNA signatures during monocyte differentiation into DCs and the new regulatory role of miR-221 and miR-155 in DC apoptosis and IL-12p70 production.

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