Performance Tables 1999-2000 (20/12/00) (PDF 155 KB)

Performance Tables 1999-2000 (20/12/00)

Silencing of c-Fos expression by microRNA-155 is critical for dendritic cell maturation and function.

MicroRNAs (miRNAs) are small, noncoding RNAs that regulate target mRNAs by binding to their 3' untranslated regions. There is growing evidence that microRNA-155 (miR155) modulates gene expression in various cell types of the immune system and is a prominent player in the regulation of innate and adaptive immune responses. To define the role of miR155 in dendritic cells (DCs) we performed a detailed analysis of its expression and function in human and mouse DCs. A strong increase in miR155 expression was found to be a general and evolutionarily conserved feature associated with the activation of DCs by diverse maturation stimuli in all DC subtypes tested. Analysis of miR155-deficient DCs demonstrated that miR155 induction is required for efficient DC maturation and is critical for the ability of DCs to promote antigen-specific T-cell activation. Expression-profiling studies performed with miR155(-/-) DCs and DCs overexpressing miR155, combined with functional assays, revealed that the mRNA encoding the transcription factor c-Fos is a direct target of miR155. Finally, all of the phenotypic and functional defects exhibited by miR155(-/-) DCs could be reproduced by deregulated c-Fos expression. These results indicate that silencing of c-Fos expression by miR155 is a conserved process that is required for DC maturation and function.

Friday Facts, October 5, 2012, Vol. 155

Bureau of Nutrition and Health Promotion part of the Iowa Department of Public Health produces of weekly newsletter about the Iowa WIC Program for the State of Iowa citizen.

MicroRNA-155 Is Required for Effector CD8(+) T Cell Responses to Virus Infection and Cancer.

MicroRNAs (miRNAs) regulate the function of several immune cells, but their role in promoting CD8(+) T cell immunity remains unknown. Here we report that miRNA-155 is required for CD8(+) T cell responses to both virus and cancer. In the absence of miRNA-155, accumulation of effector CD8(+) T cells was severely reduced during acute and chronic viral infections and control of virus replication was impaired. Similarly, Mir155(-/-) CD8(+) T cells were ineffective at controlling tumor growth, whereas miRNA-155 overexpression enhanced the antitumor response. miRNA-155 deficiency resulted in accumulation of suppressor of cytokine signaling-1 (SOCS-1) causing defective cytokine signaling through STAT5. Consistently, enforced expression of SOCS-1 in CD8(+) T cells phenocopied the miRNA-155 deficiency, whereas SOCS-1 silencing augmented tumor destruction. These findings identify miRNA-155 and its target SOCS-1 as key regulators of effector CD8(+) T cells that can be modulated to potentiate immunotherapies for infectious diseases and cancer.

Soil Erosion Control for Secondary Roads, HR-155

Research project HR-155 was initiated to study soil erosion problems along the secondary road system in Iowa and to find a substitute for straw for the control of soil erosion during the period of seed establishment. Accordingly, six field research sites were established to test the ability of commercial soil conditioners to control soil erosion. The six field research sites were selected on the basis of terrain and type of soil material exposed on the cut-slope areas.

Arkistoluettelo 155: Suomalaisen musiikin tiedotuskeskus

Luettelo Kansalliskirjastossa olevan Suomalaisen musiikin tiedotuskeskuksen käsikirjoituskokoelman sisällöstä

Circulating levels of inflammation-associated miR-155 and endothelial-enriched miR-126 in patients with end-stage renal disease

Circulating microRNAs (miRNAs) may represent a potential noninvasive molecular biomarker for various pathological conditions. Moreover, the detection of circulating miRNAs can provide important novel disease-related information. In particular, inflammation-associated miR-155 and endothelial-enriched miR-126 are reported to be associated with vascular homeostasis. Vascular damage is a common event described in end-stage renal disease (ESRD). We hypothesized that miR-155 and miR-126 may be detectable in the circulation and serve as potential biomarkers for risk stratification. In this study, we assessed miR-155 and miR-126 in the plasma of 30 ESRD patients and 20 healthy controls using real-time quantification RT-PCR. The circulating levels of miR-155 and miR-126 were significantly reduced in patients with ESRD compared to healthy controls. However, there was no significant difference of circulating miR-155 and miR-126 levels between prehemodialysis and posthemodialysis patients. Furthermore, both circulating miR-126 and miR-155 correlated positively with estimated glomerular filtration rate (miR-126: r = 0.383, P = 0.037; miR-155: r = 0.494, P = 0.006) and hemoglobin (miR-126: r = 0.515, P = 0.004; miR-155: r = 0.598, P < 0.001) and correlated inversely with phosphate level (miR-126: r = -0.675, P < 0.001; miR-155: r = -0.399, P = 0.029). Pearson’s correlation was used to compare circulating levels of miRNAs with clinical parameters. These results suggested that circulating miR-155 and miR-126 might be involved in the development of ESRD. Further studies are needed to demonstrate the role of circulating miR-155 and miR-126 as candidate biomarkers for risk estimation.