scholarly journals Feline Calicivirus Proteinase-Polymerase Degrades mRNAs to Inhibit Host Gene Expression

2021 ◽  
Author(s):  
Hongxia Wu ◽  
Jiapei Huang ◽  
Yongxiang Liu ◽  
Yudi Pan ◽  
Yin Li ◽  
...  
Keyword(s):  
Gene Expression ◽  
Immune Response ◽  
Fusion Protein ◽  
Viral Replication ◽  
Mrna Degradation ◽  
Host Gene ◽  
Ribonuclease Activity ◽  
Cellular Proteins ◽  
Feline Calicivirus

To replicate efficiently and evade the antiviral immune response of the host, some viruses degrade host mRNA to induce host gene shutoff via encoding shutoff factors. In this study, we found that feline calicivirus (FCV) infection promotes the degradation of endogenous and exogenous mRNAs and induces host gene shutoff, which results in global inhibition of host protein synthesis. Screening assay revealed that proteinase-polymerase (PP) is a most effective factor in reducing mRNA expression. Moreover, differently virulent strains of FCV PP could induce mRNA degradation. Further, we found that the key sites of the PP protein required for its proteinase activity are also essential for its shutoff activity, but also required for viral replication. The mechanism analysis showed that PP mainly targets Pol II-transcribed RNA in a ribosome-, 5’cap- and 3’ poly(A) tail-independent manner. Moreover, the purified GST-PP fusion protein exhibits ribonuclease activity in vitro in assays using GFP RNA transcribed in vitro as substrates in the absence of other viral or cellular proteins. Finally, PP-induced shutoff requires host Xrn1 to complete further RNA degradation. This study provides a newly discovered strategy in which FCV PP protein induces host gene shutoff by promoting the degradation of host mRNAs. Importance Virus infection-induced shutoff is the result of targeted or global manipulation of cellular gene expression and leads to efficient viral replication and immune evasion. FCV is a highly contagious pathogen that persistently infects cats. It is unknown how FCV blocks the host immune response and persistently exists in cats. In this study, we found that FCV infection promotes the degradation of host mRNAs and induces host gene shutoff via a common strategy. Further, PP protein for different FCV strains is a key factor that enhances mRNA degradation. An in vitro assay showed that the GST-PP fusion protein possess ribonuclease activity in the absence of other viral or cellular proteins. This study demonstrates that FCV induces host gene shutoff by promoting the degradation of host mRNAs, thereby introducing a potential mechanism by which FCV infection inhibits the immune response.

scholarly journals Therapeutic Effect of Camel Milk and Its Exosomes on MCF7 Cells In Vitro and In Vivo

2018 ◽  
Vol 17 (4) ◽  
pp. 1235-1246 ◽  
Author(s):  
Abdelnaser A. Badawy ◽  
Mohammed A. El-Magd ◽  
Sana A. AlSadrah
Keyword(s):  
Oxidative Stress ◽  
Gene Expression ◽  
Immune Response ◽  
Local Injection ◽  
Camel Milk ◽  
Anticancer Effect ◽  
Mcf7 Cells ◽  
Beneficial Effects

Background/Objectives: In the Middle East, people consume camel milk regularly as it is believed to improve immunity against diseases and decrease the risk for cancer. Recently, it was noted that most of the beneficial effects of milk come from their nanoparticles, especially exosomes. Herein, we evaluated the anticancer potential of camel milk and its exosomes on MCF7 breast cancer cells (in vitro and in vivo) and investigated the possible underlying molecular mechanism of action. Methods/Results: Administration of camel milk (orally) and its exosomes (orally and by local injection) decreased breast tumor progression as evident by ( a) higher apoptosis (indicated by higher DNA fragmentation, caspase-3 activity, Bax gene expression, and lower Bcl2 gene expression), ( b) remarkable inhibition of oxidative stress (decrease in MDA levels and iNOS gene expression); ( c) induction of antioxidant status (increased activities of SOD, CAT, and GPX), ( d) notable reduction in expression of inflammation-( IL1b, NFκB), angiogenesis-( VEGF) and metastasis-( MMP9, ICAM1) related genes; and ( e) higher immune response (high number of CD+4, CD+8, NK1.1 T cells in spleen). Conclusions: Overall, administration of camel milk–derived exosomes showed better anticancer effect, but less immune response, than treatment by camel milk. Moreover, local injection of exosomes led to better improvement than oral administration. These findings suggest that camel milk and its exosomes have anticancer effect possibly through induction of apoptosis and inhibition of oxidative stress, inflammation, angiogenesis and metastasis in the tumor microenvironment. Thus, camel milk and its exosomes could be used as an anticancer agent for cancer treatment.

MLL-AF9 and MLL-ENL Induce Deregulation of Similar Downstream Candidate Genes: An Analysis across Experimental Protocols and Laboratories.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3372-3372
Author(s):  
Ashish R. Kumar ◽  
Robert K. Slany ◽  
Jay L. Hess ◽  
John H. Kersey
Keyword(s):  
Gene Expression ◽  
Fusion Protein ◽  
Fusion Gene ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Expression Systems ◽  
Rt Pcr ◽  
Conditional Expression

Expression profiling has become an important tool for understanding gene deregulation in MLL-fusion leukemias. However, the results of gene profiling experiments are difficult to interpret when applied to leukemia cells because (i) leukemias arise in cells that differ greatly in their gene expression profiles, and (ii) leukemias most often require secondary genetic events in addition to the MLL fusion gene. Two principal model systems have been used to understand the direct effects of MLL-fusion genes. Knock-in models have the advantage of the fusion gene being under control of the physiologic promoter. On the other hand, conditional expression systems offer the ability to conduct short term experiments, permitting the analysis of direct effects on downstream genes. In the present combined-analysis, we used the Affymetrix U74Av2 oligonucleotide microarray to evaluate the effects of the MLL-fusion gene in vivo and in vitro respectively using two closely related MLL fusion genes - MLL-AF9 for knock-in and MLL-ENL for conditional expression. In the MLL-AF9 study, we compared gene expression profiles of bone marrow cells from MLL-AF9 knock-in mice (C57Bl/6, MLL-AF9+/−) to those of age-matched wild type mice (Kumar et. al. 2004, Blood). We used a t-test (p<0.05) to selected genes that showed significant changes in expression levels. In the MLL-ENL study, we transformed murine primary hematopoietic cells with a conditional MLL-ENL vector (MLL-ENL fused to the modified ligand-binding domain of the estrogen receptor) such that the fusion protein was active only in the presence of tamoxifen. We then studied the downstream effects of the fusion protein by comparing gene expression profiles of the cells in the presence and absence of tamoxifen. We used a pair-wise comparison analysis to select genes that showed a change in expression level of 1.5 fold or greater in at least two of three experiments (Zeisig et. al. 2004, Mol. Cell Biol.). Those genes that were up-regulated in both datasets were then compiled together. This list included Hoxa7, Hoxa9 and Meis1. The results for these 3 genes were confirmed by quantitative RT-PCR in both the MLL-AF9-knock-in and the MLL-ENL-conditional-expression systems. The remaining candidate genes in the common up-regulated gene set (not yet tested by quantitative RT-PCR) include protein kinases (Bmx, Mapk3, Prkcabp, Acvrl1, Cask), RAS-associated proteins (Rab7, Rab3b), signal transduction proteins (Notch1, Eat2, Shd, Fpr1), cell membrane proteins (Igsf4), chaperones (Hsp70.2), transcription factors (Isgf3g), proteins with unknown functions (Olfm1, Flot1), and hypothetical proteins. The results of the combined analysis demonstrate that these over-expressions are (i) a direct and sustained effect of the MLL-fusion protein, (ii) are independent of secondary events that might be involved in leukemogensis, and (iii) are independent of the two partner genes that participate in these fusions. The over-expression of a few genes in both the -in vitro and in vivo experimental systems makes these molecules very interesting for further studies, to understand the biology of MLL-fusion leukemias and for development of new therapeutic strategies.

Effect of IFN-γ on the immune response in vivo and on gene expression in vitro

Nature ◽  
1984 ◽  
Vol 307 (5949) ◽  
pp. 381-382 ◽  
Author(s):  
Masataka Nakamura ◽  
Tim Manser ◽  
Gregory D. N. Pearson ◽  
Michael J. Daley ◽  
Malcolm L. Gefter
Keyword(s):  
Gene Expression ◽  
Immune Response ◽  
Ifn Γ

Changes in gene expression during spherulation in Physarum polycephalum

1986 ◽  
Vol 64 (4) ◽  
pp. 337-343 ◽  
Author(s):  
François Bernier ◽  
Vern L. Seligy ◽  
Dominick Pallotta ◽  
Gérald Lemieux
Keyword(s):  
Gene Expression ◽  
Physarum Polycephalum ◽  
Electrophoretic Pattern ◽  
Cellular Proteins ◽  
Two Dimensional Gel Electrophoresis ◽  
Specific Proteins ◽  
Translatable Mrna ◽  
Electrophoresis Of Proteins

Variation of gene expression during spherulation of Physarum polycephalum microplasmodia has been studied by two-dimensional gel electrophoresis of proteins synthesized in vivo and in vitro. The electrophoretic pattern of total cellular proteins has also been analyzed during the course of differentiation. In all cases, major variations were observed and correlated with the formation of biologically mature spherules. After 24 h of differentiation, numerous specific proteins started to accumulate. After 48 h, a time at which viable spherule formation was complete, the synthesis of a set of late proteins was observed. It has also been shown that the synthesis of actin, the most abundant protein in this organism, was significantly repressed during the period at which the cells accumulated the spherule-specific proteins. The results showed that the spherulation of Physarum involves complex and major changes of protein synthesis, which occur in a temporal sequence. These variations are also observed in the population of translatable mRNA, thus suggesting an important role for RNA transcription.

scholarly journals Plasmodium falciparum Merozoite Surface Protein 1 (MSP-1)-MSP-3 Chimeric Protein: Immunogenicity Determined with Human-Compatible Adjuvants and Induction of Protective Immune Response

2009 ◽  
Vol 78 (2) ◽  
pp. 872-883 ◽  
Author(s):  
Suman Mazumdar ◽  
Paushali Mukherjee ◽  
Syed Shams Yazdani ◽  
S. K. Jain ◽  
Asif Mohmmed ◽  
...  
Keyword(s):  
Immune Response ◽  
Plasmodium Falciparum ◽  
Fusion Protein ◽  
Malaria Vaccine ◽  
Chimeric Protein ◽  
Surface Protein ◽  
Merozoite Surface Protein ◽  
Protective Immune Response ◽  
Merozoite Surface Protein 1

ABSTRACT A chimeric gene, MSP-Fu24 , was constructed by genetically coupling immunodominant, conserved regions of the two leading malaria vaccine candidates, Plasmodium falciparum merozoite surface protein 1 (C-terminal 19-kDa region [PfMSP-119]) and merozoite surface protein 3 (11-kDa conserved region [PfMSP-311]). The recombinant MSP-Fu24 protein was produced in Escherichia coli cells and purified to homogeneity by a two-step purification process with a yield of ∼30 mg/liter. Analyses of conformational properties of MSP-Fu24 using PfMSP-119-specific monoclonal antibody showed that the conformational epitopes of PfMSP-119 that may be critical for the generation of the antiparasitic immune response remained intact in the fusion protein. Recombinant MSP-Fu24 was highly immunogenic in mice and in rabbits when formulated with two different human-compatible adjuvants and induced an immune response against both PfMSP-119 and PfMSP-311. Purified anti-MSP-Fu24 antibodies showed invasion inhibition of P. falciparum 3D7 and FCR parasites, and this effect was found to be dependent on antibodies specific for the PfMSP-119 component. The protective potential of MSP-Fu24 was demonstrated by in vitro parasite growth inhibition using an antibody-dependent cell inhibition (ADCI) assay with anti-MSP-Fu24 antibodies. Overall, the antiparasitic activity was mediated by a combination of growth-inhibitory antibodies generated by both the PfMSP-119 and PfMSP-311 components of the MSP-Fu24 protein. The antiparasitic activities elicited by anti-MSP-Fu24 antibodies were comparable to those elicited by antibodies generated with immunization with a physical mixture of two component antigens, PfMSP-119 and PfMSP-311. The fusion protein induces a protective immune response with human-compatible adjuvants and may form a part of a multicomponent malaria vaccine.

scholarly journals Differential gene expression elicited by ZIKV infection in trophoblasts from congenital Zika syndrome discordant twins

2019 ◽  
Author(s):  
Murilo Sena Amaral ◽  
Ernesto Goulart ◽  
Luiz Carlos Caires-Júnior ◽  
David Abraham Morales-Vicente ◽  
Alessandra Soares-Schanoski ◽  
...  
Keyword(s):  
Gene Expression ◽  
Immune Response ◽  
Genetic Background ◽  
Zikv Infection ◽  
Dizygotic Twins ◽  
Susceptibility Factors ◽  
Congenital Zika Syndrome ◽  
Host Genetic ◽  
Discordant Twins

AbstractZika virus (ZIKV) causes congenital Zika syndrome (CZS), which is characterized by fetal demise, microcephaly and other abnormalities. ZIKV in the pregnant woman circulation must cross the placental barrier that includes fetal endothelial cells and trophoblasts, in order to reach the fetus. CZS occurs in ∼1-40% of cases of pregnant women infected by ZIKV, suggesting that mothers’ infection by ZIKV during pregnancy is not deterministic for CZS phenotype in the fetus. Therefore, other susceptibility factors might be involved, including the host genetic background. We have previously shown that in three pairs of dizygotic twins discordant for CZS, neural progenitor cells (NPCs) from the CZS-affected twins presented differential in vitro ZIKV susceptibility compared with NPCs from the non-affected. Here, we analyzed human-induced-pluripotent-stem-cell-derived (hiPSC-derived) trophoblasts from these twins and compared by RNA-Seq the trophoblasts from CZS-affected and non-affected twins. Following in vitro exposure to a Brazilian ZIKV strain (ZIKVBR), trophoblasts from CZS-affected twins were significantly more susceptible to ZIKVBR infection when compared with trophoblasts from the non-affected. Transcriptome profiling revealed no differences in gene expression levels of ZIKV candidate attachment factors, IFN receptors and IFN in the trophoblasts, either before or after ZIKVBR infection. Most importantly, ZIKVBR infection caused, only in the trophoblasts from CZS-affected twins, the downregulation of genes related to extracellular matrix organization and to leukocyte activation, which are important for trophoblast adhesion and immune response activation. In addition, only trophoblasts from non-affected twins secreted significantly increased amounts of chemokines RANTES/CCL5 and IP10 after infection with ZIKVBR. Overall, our results showed that trophoblasts from non-affected twins have the ability to more efficiently activate genes that are known to play important roles in cell adhesion and in triggering the immune response to ZIKV infection in the placenta, and this may contribute to predict protection from ZIKV dissemination into fetuses’ tissues.Author summaryThe Zika virus (ZIKV) infection in adults is usually characterized by mild flu-like symptoms, with most cases remaining asymptomatic. However, in the last years, widespread ZIKV infection was shown for the first time to be associated with congenital Zika syndrome (CZS) and death of neonates. CZS is a very debilitating condition that includes microcephaly and mental retardation, leading to a strong social and health impact. This dramatic condition calls for a careful evaluation of the molecular mechanisms involved in ZIKV infection in the maternal-fetal interface. It is estimated that CZS occurs in ∼1-40% of cases of pregnant women infected by ZIKV, which suggests that different susceptibility factors might be involved, including the host genetic background. By analyzing trophoblast cells that recapitulate the placenta from three pairs of dizygotic twins discordant for CZS, we were able to show that trophoblasts from CZS-affected twins were significantly more susceptible to ZIKV infection when compared with trophoblasts from the non-affected twins. We also provide a detailed picture of genes differentially expressed by trophoblasts from the discordant twins after infection with ZIKV. These genes can be further investigated as possible therapeutic targets to avoid viral dissemination into developing fetus’ tissues.

scholarly journals PI3K/mTOR and topoisomerase inhibitors with potential activity against SARS-CoV-2 infection

2020 ◽  
Author(s):  
James Robert White ◽  
Michael Bonner Foote ◽  
Justin Jee ◽  
Guillem Argilés ◽  
Jonathan C.M. Wan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Clinical Data ◽  
Statistical Evaluation ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Mtor Pathway ◽  
Host Gene ◽  
Topoisomerase Inhibitors ◽  
Potential Activity

There is an urgent need to identify therapies to prevent and treat SARS-CoV-2 infection. We performed a statistical evaluation of in vitro gene expression profiles reflecting exposure to 1,835 drugs, and found topoisomerase inhibitors and PI3K/mTOR pathway inhibitors among the strongest candidates for reduced expression of ACE2, a host gene associated with SARS-CoV-2 infection. Retrospective clinical data suggest that patients on these agents may be less likely to test positive for SARS-CoV-2.

scholarly journals Novel cytokine–antibody fusion protein, N-820, to enhance the functions of ex vivo expanded natural killer cells against Burkitt lymphoma

2020 ◽  
Vol 8 (2) ◽  
pp. e001238
Author(s):  
Yaya Chu ◽  
Gaurav Nayyar ◽  
Nang Kham Su ◽  
Jeremy M Rosenblum ◽  
Patrick Soon-Shiong ◽  
...  
Keyword(s):  
Gene Expression ◽  
Growth Factors ◽  
Fusion Protein ◽  
Natural Killer ◽  
Burkitt Lymphoma ◽  
Ex Vivo ◽  
Specific Binding ◽  
Expression Profiles ◽  
Nsg Mice

BackgroundThe prognosis of patients with relapsed or progressive B cell (CD20+) non-Hodgkin’s lymphoma (B-NHL), including Burkitt lymphoma (BL), is dismal due to chemoradiotherapy resistance. Novel therapeutic strategies are urgently needed. N-820 is a fusion protein of N-803 (formerly known as ALT-803) to four single-chains of rituximab. This agent has tri-specific binding activity to CD20 and enhanced antibody-dependent cell-mediated cytotoxicity.MethodsWe investigated the anti-tumor combinatorial effects of N-820 with ex vivo expanded peripheral blood natural killer (exPBNK) cells against rituximab-sensitive and rituximab-resistant CD20+ BL in vitro using cytoxicity assays and in vivo using human BL xenografted NOD/SCID/IL2rγnull (NSG) mice. We also investigated the cytokines/chemokines/growth factors released using ELISA and multiplex assay. Gene expression changes were examined using real-time PCR arrays.ResultsN-820 significantly enhanced the expression of NK activating receptors (p<0.001) and the proliferation of exPBNK cells with enhanced Ki67 expression and Stat5 phosphorylation (p<0.001). N-820 significantly enhanced the secretion of cytokines, chemokines, and growth factors including GM-CSF, RANTES, MIP-1B (p<0.001) from exPBNK cells as compared with the combination of rituximab+N-803. Importantly, N-820 significantly enhanced in vitro cytotoxicity (p<0.001) of exPBNK with enhanced granzyme B and IFN-γ release (p<0.001) against BL. Gene expression profiles in exPBNK stimulated by N-820+Raji-2R showed enhanced transcription of CXCL9, CXCL1, CSF2, CSF3, GZMB, and IFNG. Moreover, N-820 combined with exPBNK significantly inhibited rituximab-resistant BL growth (p<0.05) and extended the survival (p<0.05) of BL xenografted NSG mice.ConclusionsOur results provide the rationale for the development of a clinical trial of N-820 alone or in combination with endogenous or ex vivo expanded NK cells in patients with CD20+ B-NHL failing prior rituximab containing chemoimmunotherapy regimens.

scholarly journals Prodigiosin Modulates the Immune Response and Could Promote a Stable Atherosclerotic Lession in C57bl/6 Ldlr-/- Mice

2020 ◽  
Vol 21 (17) ◽  
pp. 6417 ◽  
Author(s):  
Alejandro Cuevas ◽  
Nicolás Saavedra ◽  
Luis A. Salazar ◽  
Marcela F. Cavalcante ◽  
Jacqueline C. Silva ◽  
...  
Keyword(s):  
Gene Expression ◽  
Immune Response ◽  
Atherosclerotic Plaque ◽  
Therapeutic Potential ◽  
Inflammatory Marker ◽  
Interleukin 2 ◽  
Atheromatous Plaque ◽  
In Vitro Tests ◽  
Significant Difference

Atherosclerosis is a chronic inflammatory disease, whose progression and stability are modulated, among other factors, by an innate and adaptive immune response. Prodiginines are bacterial secondary metabolites with antiproliferative and immunomodulatory activities; however, their effect on the progression or vulnerability of atheromatous plaque has not been evaluated. This study assessed the therapeutic potential of prodigiosin and undecylprodigiosin on inflammatory marker expression and atherosclerosis. An in vitro and in vivo study was carried out. Migration, low-density lipoprotein (LDL) uptake and angiogenesis assays were performed on cell types involved in the pathophysiology of atherosclerosis. In addition, male LDL receptor null (Ldlr-/-) C57BL/6J mice were treated with prodigiosin or undecylprodigiosin for 28 days. Morphometric analysis of atherosclerotic plaques, gene expression of atherogenic factors in the aortic sinus and serum cytokine quantification were performed. The treatments applied had slight effects on the in vitro tests performed, highlighting the inhibitory effect on the migration of SMCs (smooth muscle cells). On the other hand, although no significant difference in atherosclerotic plaque progression was observed, gene expression of IL-4 and chemokine (C-C motif) ligand 2 (Ccl2) was downregulated. In addition, 50 µg/Kg/day of both treatments was sufficient to inhibit circulating tumor necrosis factor alpha (TNF-α), interleukin-2 (IL-2) and interferon-gamma (IFN-γ) in serum. These results suggested that prodigiosin and undecylprodigiosin modulated inflammatory markers and could have an impact in reducing atherosclerotic plaque vulnerability.

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