AI Article Synopsis
- HCV genotype 1 shows resistance to interferon therapy, potentially due to the functional inhibition of the antiviral protein PKR, though its efficacy against HCV in the body is unclear.
- Using a novel technique, researchers studied the localization of PKR protein in the liver tissue of four chronic HCV patients, comparing it to normal cells and liver samples.
- PKR was primarily found in the nucleus and cytoplasm of HCV patients' cells, with a notable pattern similar to that found in normal cells, indicating a possible increase in PKR protein in HCV diseased tissue compared to normal liver.
Article Abstract
The greater resistance of HCV genotype 1 infection to IFN therapy has been partially attributed to functional inhibition of the type 1 interferon induced anti-viral protein PKR in vitro. Whether PKR has antiviral activity against HCV in vivo is unknown. Whilst the ultra-structural localisation of PKR is known in vitro, it is not defined in chronic hepatitis C disease. Using a novel immuno-gold technique we characterised the expression of intrahepatic PKR protein at the ultra-structural level in four patients with chronic HCV disease compared to normal human PBMCs, HepG2 cells and a normal human liver biopsy. All four HCV patients labelled for PKR protein, localising to the nucleus, nucleolus and cytoplasm. Nuclear labelling was confined mainly to the nucleolus and euchromatin. Cytoplasmic labelling was evident within smooth vesicles. Strong immunogold labelling was also evident within the cisternae of the rough endoplasmic reticulum. A similar pattern of ultra-structural nuclear and cytoplasmic PKR protein labelling was seen in PBMCs from healthy donors, HepG2 cells and a normal liver biopsy. The mean nuclear and cytoplasmic count for PKR protein in the HCV group was 21 +/- 4 and 18 +/- 3 gold particles/microm(2), respectively. This represented an increase, though not statistically significant, in nuclear and cytoplasmic labelling for PKR protein in HCV biopsies relative to normal liver tissue.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/s10735-009-9227-0 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Reduced White Matter Damage and Lower Neuroinflammatory Potential of Microglia and Macrophages in Hri/Eif2ak1 Mice After Contusive Spinal Cord Injury.
Glia
January 2025
Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, Kentucky, USA.
Cellular stressors inhibit general protein synthesis while upregulating stress response transcripts and/or proteins. Phosphorylation of the translation factor eIF2α by one of the several stress-activated kinases is a trigger for such signaling, known as the integrated stress response (ISR). The ISR regulates cell survival and function under stress.
View Article and Find Full Text PDFPKR Inhibitor C16 Regulates HIV-gp120 Induced Neuronal Injury and Cognitive Impairment in Vivo and in Vitro Models.
Neurochem Res
January 2025
College of Pharmacy, Guangxi Medical University, Guangxi Zhuang Autonomous Region, Nanning, 530021, China.
To study the neuronal protective effect and its potential mechanism of C16 against gp120-induced cognitive impairment in vitro and in vivo. The NORT method was used to evaluate the short-term memory abilities of rats, the morphological changes in hippocampus were observed by Nissl staining. Cell viability and damage degree were detected by MTT and LDH.
View Article and Find Full Text PDFRole of mouse adenovirus type 1 E4orf6-induced degradation of protein kinase R in pathogenesis.
J Virol
December 2024
Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA.
Protein kinase R (PKR) is an interferon-induced antiviral protein activated by autophosphorylation in response to double strand DNA (dsRNA) and other stimuli. Activated PKR causes translation inhibition and apoptosis, and it contributes to proinflammatory responses, cell growth, and differentiation. Mouse adenovirus type 1 (MAV-1) counteracts PKR by causing its degradation via a viral protein, early region 4 open reading frame 6 (E4orf6).
View Article and Find Full Text PDFMulti-Omics Study Reveals Nc886/vtRNA2-1 as a Positive Regulator of Prostate Cancer Cell Immunity.
J Proteome Res
December 2024
Facultad de Ciencias, Universidad de la República, Sección Genómica Funcional, Montevideo 11400, Uruguay.
Noncoding RNA 886 has emerged as a pivotal regulatory RNA with distinct functions across tissues, acting as a regulator of protein activity by directly binding to protein partners. While it is well recognized as a tumor suppressor in prostate cancer, the underlying molecular mechanisms remain elusive. To discover the principal pathways regulated by nc886 in prostate cancer, we used a transcriptomic and proteomic approach analyzing malignant DU145, LNCaP, PC3, and benign RWPE-1 prostate cell line models transiently transfected with in vitro transcribed nc886 or antisense oligonucleotides.
View Article and Find Full Text PDFBlocking feedback immunosuppression of antigen presentation in brain tumor during oncolytic virotherapy with oHSV-mshPKR.
Mol Cancer Ther
December 2024
Augusta University, Augusta, Georgia, United States.
Glioblastoma (GBM) is the most frequent malignant brain tumor. We recently discovered that oncolytic herpes simplex virus engineered to disable tumor-intrinsic protein kinase R (PKR) signaling (oHSV-shPKR) could increase oHSV oncolysis and anti-tumor immune response. However, here we show that disabling tumor-intrinsic PKR signaling can also induce the activation of the indoleamine 2,3-dioxygenase (IDO) signaling pathway.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!