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Porcine reproductive and respiratory syndrome virus (PRRSV) infection inhibits swine leukocyte antigen class I (SLA-I) expression in pigs, resulting in inefficient antigen presentation and subsequent low levels of cellular PRRSV-specific immunity as well as persistent viremia. We previously observed that the non-structural protein 4 (nsp4) of PRRSV contributed to inhibition of the β2-microglobulin (β2M) and SLA-I expression in cells. Here, we constructed a series of nsp4 mutants with different combination of amino acid mutations to attenuate the inhibitory effect of nsp4 on β2M and SLA-I expression. Almost all nsp4 mutants exogenously expressed in cells showed an attenuated effect on inhibition of β2M and SLA-I expression, but the recombinant PRRSV harboring these nsp4 mutants failed to be rescued with exception of the rPRRSV-nsp4-mut10 harboring three amino acid mutations. However, infection of rPRRSV-nsp4-mut10 not only enhanced β2M and SLA-I expression in both cells and pigs but also promoted the DCs to active the CD3+CD8+T lymphocytes more efficiently, as compared with its parental PRRSV (rPRRVS-nsp4-wt). These data suggested that the inhibition of nsp4-mediated β2M downregulation improved β2M/SLA-I expression in pigs. • The Nsp4 gene of PRRSV on virus level inhibit the expression of β2M/SLA-I gene in pigs in this research filed. • The three amino acid sites of Nsp4 gene we have screened play a key role in inhibition of the expression of β2M/SLA-I gene in pigs. • The rPRRSV-nsp4-mut10 can induce more expression of β2M/SLA-I which accelerates the clearance of PRRSV in pigs. [ABSTRACT FROM AUTHOR]

Purpose: Abnormal CD38 expression in some hematologic malignancies, including lymphoma, has made it a biomarker for targeted therapies. Daratumumab (Dara) is the first FDA-approved CD38-specific monoclonal antibody, enabling successfully immunoPET imaging over the past years. Radiolabeled Dara however has a long blood circulation and delayed tumor uptake which can limit its applications. The focus of this study is to develop 64Cu-labeled Dara-F(ab′)2 for the visualization of CD38 in lymphoma models. Methods: F(ab′)2 fragment was prepared from Dara using an IdeS enzyme and purified with Protein A beads. Western blotting, flow cytometry, and surface plasmon resonance (SPR) were performed for in vitro assay. Probes were labeled with 64Cu after the chelation of 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA). Small animal PET imaging and quantitative analysis were performed after injection of 64Cu-labeled Dara-F(ab′)2, IgG-F(ab′)2, and Dara for evaluation in lymphoma models. Results: Flow cytometry and SPR assay proved the specific binding ability of Dara-F(ab′)2 and NOTA-Dara-F(ab′)2 in vitro. Radiolabeling yield of [64Cu]Cu-NOTA-Dara-F(ab′)2 was over 90% and with a specific activity of 4.0 ± 0.6 × 103 MBq/μmol (n = 5). PET imaging showed [64Cu]Cu-NOTA-Dara-F(ab′)2 had a rapid and high tumor uptake as early as 2 h (6.9 ± 1.2%ID/g) and peaked (9.5 ± 0.7%ID/g) at 12 h, whereas [64Cu]Cu-NOTA-Dara reached its tumor uptake peaked at 48 h (8.3 ± 1.4%ID/g, n = 4). In comparison, IgG-F(ab′)2 and HBL-1 control groups found no noticeable tumor uptake. [64Cu]Cu-NOTA-Dara-F(ab′)2 had significantly lower uptake in blood pool, bone, and muscle than [64Cu]Cu-NOTA-Dara and its tumor-to-blood and tumor-to-muscle ratios were significantly higher than controls. Conclusions: [64Cu]Cu-NOTA-Dara-F(ab′)2 showed a rapid and high tumor uptake in CD38-positive lymphoma models with favorable imaging contrast, showing its promise as a potential PET imaging agent for future clinical applications. [ABSTRACT FROM AUTHOR]

Purpose We investigated whether a 99m Tc radiolabeled anti-miRNA-155 oligonucleotide (AMO-155) could visualize the expression of miR-155 in multiple kinds of tumors in vivo . Methods AMO-155 was chemically synthesized and modified with 2′- O -methyl (2′-OMe) and phosphorothioate (PS). It was radiolabeled with 99m Tc via the conjugation with NHS-MAG3 at 5′ end. The characterization of radiolabeling and serum stability was evaluated using high performance liquid chromatography (HPLC) and agarose gel electrophoresis. The expression of C/EBPβ, one of the miR-155 target proteins, was assessed using Western blot. The cellular uptake and delivery of AMO-155 was further evaluated in tumor cells. 99m Tc-AMO-155 was tested in vivo in multiple tumor models, including miR-155 over-expressed and low-expressed tumor models. Finally, biodistribution of 99m Tc-AMO-155 was evaluated. Results 99m Tc-AMO-155 was prepared with high yield and radiochemical purity. It showed high stability in fresh human serum for 10 h. 99m Tc-AMO-155 displayed comparable capacity as unlabeled AMO-155 to increase the expression of C/EBPβ protein in MCF-7 cells. 99m Tc-AMO-155 showed an increased radioactive uptake in MCF-7 cells after 8 h of incubation, whereas no change of 99m Tc-pertechnetate uptake was observed. Carboxyfluorescein (FAM) labeled AMO-155 had higher fluorescent delivery than Control in HeLa and HepG2 cells by confocal microscopy. In miR-155 over-expressed tumor models, 99m Tc-AMO-155 showed significantly higher tumor accumulation than 99m Tc-Control. Furthermore, 99m Tc-AMO-155 was capable of discriminating between MCF-7 and MDA-MB-231 tumors based on their expression of miR-155. Conclusions Our study successfully prepared and proved 99m Tc-AMO-155 as a prospective imaging agent for the noninvasive visualization of miR-155 expression in vivo . [ABSTRACT FROM AUTHOR]

Highlights: [•] miR-30a represses Eya2 expression by binding to the 3′-untranslated region of Eya2. [•] The miR-30a/EYA2 axis regulates breast cancer cell proliferation and migration. [•] The miR-30a/EYA2 axis modulates G1/S cell cycle progression. [•] The miR-30a/EYA2 axis is dysregulated in breast cancer patients. [ABSTRACT FROM AUTHOR]

Abstract: HCV and HBV are the major causes of chronic liver diseases worldwide. Patients with both viruse’s co-infection tend to develop severer liver diseases and are at high risk of liver-related death. NS5A protein of HCV plays key roles in HCV replication and inhibition of host immune responses. In this study, we described the establishment of HepG2-derived cell line that stably expresses NS5A protein and the application of a cellular system for HBV replication based on a recombinant adenovirus carrying HBV genome. Our results demonstrated that NS5A enhances the expression of S and E proteins of HBV, as well as the synthesis of viral DNA. Moreover, we showed that NS5A assists HBV to escape interferon responses. These data suggested that NS5A of HCV may employ multiple strategies contributing to the enhancement of HBV replication and interferon resistance during the co-infection of HCV and HBV. [Copyright &y& Elsevier]

The aneuploidy chromosome addition lines with individual chromosomes of one species into the whole genome of another species developed from interspecific or intergeneric crosses are ideal for studying the gene expression regulation under asymmetrical genome interactions. Here, we chose two rapeseed-radish addition lines (2n=40, AACC+2R) with all chromosomes of rapeseed and one pair of radish chromosomes carrying 25S rDNA loci and both 5S and 25S rDNA loci, respectively. Transcriptome sequencing of these two rapeseed-radish addition lines, together with two parents (Brassica napus, 2n=38, AACC; Raphanus sativus, 2n=18, RR), was performed to assess gene expression changes due to the aneuploidy effect. Our results showed that the global gene expression perturbations in two addition lines showed asymmetric distributions between A and C subgenomes, for more downregulated genes located in the C subgenome. Moreover, several dysregulated domains occurred in the addition lines and majority of them were clustered in C subgenome, further revealing that C subgenome was more inclined to be repressed by the aneuploidy. Homoeolog expression was slightly biased toward C subgenome in the parent B. napus, but had no preference to either of A or C subgenome in the addition lines. The total number of biased genes increased sharply and most of them were shared only by two addition lines, indicating that aneuploidy could change the extent and direction of homoeolog expression. The triplicated subgenomes which were orthologs to the chromosomes of Arabidopsis thaliana also exhibited dramatic alternations in two additions. Together, our results revealed that the addition of individual radish chromosomes could induce dramatically transcriptomic disturbances and those expression changes gave asymmetric distributions between two subgenomes in B. napus. The possible mechanisms including the uniparental expression of rRNA genes in the allopolyploids and additions for the findings are discussed. [ABSTRACT FROM AUTHOR]

Summary Aerobic glycolysis (the Warburg effect) facilitates tumor growth, and drugs targeting aerobic glycolysis are being developed. However, how the Warburg effect is directly regulated is largely unknown. Here we show that transcription factor SIX1 directly increases the expression of many glycolytic genes, promoting the Warburg effect and tumor growth in vitro and in vivo . SIX1 regulates glycolysis through HBO1 and AIB1 histone acetyltransferases. Cancer-related SIX1 mutation increases its ability to promote aerobic glycolysis and tumor growth. SIX1 glycolytic function is directly repressed by microRNA-548a-3p, which is downregulated, inversely correlates with SIX1, and is a good predictor of prognosis in breast cancer patients. Thus, the microRNA-548a-3p/SIX1 axis strongly links aerobic glycolysis to carcinogenesis and may become a promising cancer therapeutic target. [ABSTRACT FROM AUTHOR]

Enterovirus 71 (EV71) is one causative agent of hand, foot, and mouth disease (HFMD), which may lead to severe neurological disorders and mortality in children. EV71 genome is a positive single-stranded RNA containing a single open reading frame (ORF) flanked by 5′-untranslated region (5′UTR) and 3′UTR. The 5′UTR is fundamentally important for virus replication by interacting with cellular proteins. Here, we revealed that poly(C)-binding protein 1 (PCBP1) specifically binds to the 5′UTR of EV71. Detailed studies indicated that the RNA-binding K-homologous 1 (KH1) domain of PCBP1 is responsible for its binding to the stem-loop I and IV of EV71 5′UTR. Interestingly, we revealed that PCBP1 is distributed in the nucleus and cytoplasm of uninfected cells, but mainly localized in the cytoplasm of EV71-infected cells due to interaction and co-localization with the viral RNA. Furthermore, sub-cellular distribution analysis showed that PCBP1 is located in ER-derived membrane, in where virus replication occurred in the cytoplasm of EV71-infected cells, suggesting PCBP1 is recruited in a membrane-associated replication complex. In addition, we found that the binding of PCBP1 to 5′UTR resulted in enhancing EV71 viral protein expression and virus production so as to facilitate viral replication. Thus, we revealed a novel mechanism in which PCBP1 as a positive regulator involved in regulation of EV71 replication in the host specialized membrane-associated replication complex, which provides an insight into cellular factors involved in EV71 replication. [ABSTRACT FROM AUTHOR]

Abstract: The overexpression of osteopontin is associated with various inflammatory liver diseases. Interestingly, each of these diseases is also associated with IL-17 expression. Therefore, we sought to determine whether there is any mechanistic link between osteopontin and IL-17. Herein we show that IL-17 and osteopontin levels were significantly increased in patients with chronic hepatitis B. We found that IL-17 and osteopontin levels increased similarly in mice with concanavalin A-induced hepatitis. Both osteopontin- and IL-17-deficient mice were resistant to concanavalin A-induced hepatic injury. In addition, osteopontin markedly induced IL-17 expression by leukocytes (from humans and mice). This effect could be blocked by a specific antibody against osteopontin. β3 integrin (one of the osteopontin receptors) was critically involved in the induction of IL-17 production by osteopontin. Osteopontin-induced IL-17 expression was mediated through the p38, JNK, and NF-κB pathways. These findings suggest that osteopontin regulates IL-17 production during the pathogenesis of hepatitis and provide new evidence for the critical roles of osteopontin and IL-17 in hepatitis. [Copyright &y& Elsevier]