• Title/Summary/Keyword: Helper proteins

Search Result 23, Processing Time 0.023 seconds

Helper virus-free gutless adenovirus (HF-GLAd): a new platform for gene therapy

  • Liu, Jida;Seol, Dai-Wu
    • BMB Reports
    • /
    • v.53 no.11
    • /
    • pp.565-575
    • /
    • 2020
  • Gene therapy is emerging as a treatment option for inherited genetic diseases. The success of this treatment approach greatly depends upon gene delivery vectors. Researchers have attempted to harness the potential of viral vectors for gene therapy applications over many decades. Among the viral vectors available, gutless adenovirus (GLAd) has been recognized as one of the most promising vectors for in vivo gene delivery. GLAd is constructed by deleting all the viral genes from an adenovirus. Owing to this structural feature, the production of GLAd requires a helper that supplies viral proteins in trans. Conventionally, the helper is an adenovirus. Although the helper adenovirus efficiently provides helper functions, it remains as an unavoidable contaminant and also generates replication-competent adenovirus (RCA) during the production of GLAd. These two undesirable contaminants have raised safety concerns and hindered the clinical applications of GLAd. Recently, we developed helper virus-free gutless adenovirus (HF-GLAd), a new version of GLAd, which is produced by a helper plasmid instead of a helper adenovirus. Utilization of this helper plasmid eliminated the helper adenovirus and RCA contamination in the production of GLAd. HF-GLAd, devoid of helper adenovirus and RCA contaminants, will facilitate its clinical applications. In this review, we discuss the characteristics of adenoviruses, the evolution and production of adenoviral vectors, and the unique features of HF-GLAd as a new platform for gene therapy. Furthermore, we highlight the potential applications of HF-GLAd as a gene delivery vector for the treatment of various inherited genetic diseases.

Genetic Factors Affecting Insecticidal Crystal Protein Synthesis in Bacillus thuringiensis

  • Park, Hyung-Woo;Brian A. Federici
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.1 no.1
    • /
    • pp.1-7
    • /
    • 2000
  • Early studies of the molecular biology of Bacillus thuringeinsis suggested that genetic manipulation of this species could create combinations of genes more useful than those known to occur in natural isolates. Breakthroughs that made these manipulations possible include the cloning of many genes encoding endotoxins, the development of transformation vectors, and various PCR techniques. This paper reviews several genetic factors such as promoters, a 5'mRNA stabilizing sequence, 3'transcription termination sequences, and helper proteins that have been used to enhance crystal protein synthesis, and shows how these genetic elements can be manipulated with new molecular tools to develop more efficacious strains of B. thuringiensis.

  • PDF

Characterization of the in vitro Activities of the P1 and Helper Component Proteases of Soybean mosaic virus Strain G2 and Tobacco vein mottling virus

  • Lim, Hyoun-Sub;Jang, Chan-Yong;Nam, Ji-Ryun;Li, Meijia;Hong, Jin-Sung;Bae, Han-Hong;Ju, Ho-Jong;Kim, Hong-Gi;Ford, Richard E.;Domier, Leslie L.
    • The Plant Pathology Journal
    • /
    • v.28 no.2
    • /
    • pp.197-201
    • /
    • 2012
  • Potyviruses express their RNA genomes through the production of polyproteins that are processed in host cells by three virus-encoded proteases. Soybean plants produce large amounts of protease inhibitors during seed development and in response to wounding that could affect the activities of these proteases. The in vitro activities of two of the proteases of Soybean mosaic virus (SMV) and Tobacco vein mottling virus (TVMV) were compared in the rabbit reticulocyte lysate in vitro translation system using synthetic RNA transcripts. Transcripts produced from SMV and TVMV cDNAs that included the P1 and helper component-protease (HC-Pro) coding regions directed synthesis of protein products that were only partially processed. Unprocessed poly-proteins were not detected from transcripts that included all of the P1, HC-Pro, P3 and portions of the cylindrical inclusion protein coding regions of either virus. Addition of soybean trypsin inhibitor to in vitro translation reactions increased the accumulation of the unprocessed polyprotein from TVMV transcripts, but did not alter the patterns of proteins produced from SMV. These experiments suggest that SMV-and TVMV-encoded proteases are differentially sensitive to protease inhibitors.

HaCaT Keratinocytes and Primary Epidermal Keratinocytes Have Different Transcriptional Profiles of Cornified Envelope-Associated Genes to T Helper Cell Cytokines

  • Seo, Min-Duk;Kang, Tae-Jin;Lee, Chang-Hoon;Lee, Ai-Young;Noh, Min-Soo
    • Biomolecules & Therapeutics
    • /
    • v.20 no.2
    • /
    • pp.171-176
    • /
    • 2012
  • HaCaT cells are the immortalized human keratinocytes and have been extensively used to study the epidermal homeostasis and its pathophysiology. T helper cells play a role in various chronic dermatological conditions and they can affect skin barrier homeostasis. To evaluate whether HaCaT cells can be used as a model cell system to study abnormal skin barrier development in various dermatologic diseases, we analyzed the gene expression profile of epidermal differentiation markers of HaCaT cells in response to major T helper (Th) cell cytokines, such as $IFN{\gamma}$, IL-4, IL-17A and IL-22. The gene transcriptional profile of cornified envelope-associated proteins, such as filaggrin, loricrin, involucrin and keratin 10 (KRT10), in HaCaT cells was generally different from that in normal human keratinocytes (NHKs). This suggests that HaCaT cells have a limitation as a model system to study the pathophysiological mechanism associated with the Th cell cytokine-dependent changes in cornified envelope-associated proteins which are essential for normal skin barrier development. In contrast, the gene transcription profile change of human ${\beta}2$-defensin (HBD2) in response to $IFN{\gamma}$, IL-4 or IL-17A in HaCaT cells was consistent with the expression pattern of NHKs. $IFN{\gamma}$ also up-regulated transglutaminase 2 (TGM2) gene transcription in both HaCaT cells and NHKs. As an alternative cell culture system for NHKs, HaCaT cells can be used to study molecular mechanisms associated with abnormal HBD2 and TGM2 expression in response to $IFN{\gamma}$, IL-4 or IL-17A.

Interaction Study of Soybean mosaic virus Proteins with Soybean Proteins using the Yeast-Two Hybrid System

  • Seo, Jang-Kyun;Hwang, Sung-Hyun;Kang, Sung-Hwan;Choi, Hong-Soo;Lee, Su-Heon;Sohn, Seong-Han;Kim, Kook-Hyung
    • The Plant Pathology Journal
    • /
    • v.23 no.4
    • /
    • pp.281-286
    • /
    • 2007
  • Interactions between viral proteins and host proteins are essential for virus replication. Especially, translation of viral genes completely depends on the host machinery. In potyviruses, interactions of genome-linked viral protein (VPg) with host translation factors including eIF4E, eIF(iso)4E, and poly(A)-binding protein (PABP) has previously been characterized. In this study, we investigated interactions between Soybean mosaic virus (SMV) viral proteins and host translation factors by yeast two-hybrid system. SMV VPg interacted with eIF4E, eIF(iso)4E, and PABP in yeast two-hybrid system, while SMV helper component proteinase (HC-pro) interacted with neither of those proteins. The interaction between SMV NIb and PABP was also detected. These results are consistent with those reported previously in other potyviruses. Interestingly, we found reproducible and specific interactions between SMV coat protein (CP) and PABP. Deletion analysis showed that the region of CP comprising amino acids 116 to 206 and the region of PABP comprising amino acids 520 to 580 are involved in CP/PABP interactions. Soybean library screening with SMV NIb by yeast two-hybrid assay also identified several soybean proteins including chlorophyll a/b binding preprotein, photo-system I-N subunit, ribulose 1,5-biphosphate carboxylase, ST-LSI protein, translation initiation factor 1, TIR-NBS type R protein, RNA binding protein, ubiquitin, and LRR protein kinase. Altogether, these results suggest that potyviral replicase may comprise a multi-protein complex with PABP, CP, and other host factors.

A Fuzzy Continuous Petri Net Model for Helper T cell Differentiation

  • Park, In-Ho;Na, Do-Kyun;Lee, Kwang-H.;Lee, Do-Heon
    • Proceedings of the Korean Society for Bioinformatics Conference
    • /
    • 2005.09a
    • /
    • pp.344-347
    • /
    • 2005
  • Helper T(Th) cells regulate immune response by producing various kinds of cytokines in response to antigen stimulation. The regulatory functions of Th cells are promoted by their differentiation into two distinct subsets, Th1 and Th2 cells. Th1 cells are involved in inducing cellular immune response by activating cytotoxic T cells. Th2 cells trigger B cells to produce antibodies, protective proteins used by the immune system to identify and neutralize foreign substances. Because cellular and humoral immune responses have quite different roles in protecting the host from foreign substances, Th cell differentiation is a crucial event in the immune response. The destiny of a naive Th cell is mainly controlled by cytokines such as IL-4, IL-12, and IFN-${\gamma}$. To understand the mechanism of Th cell differentiation, many mathematical models have been proposed. One of the most difficult problems in mathematical modeling is to find appropriate kinetic parameters needed to complete a model. However, it is relatively easy to get qualitative or linguistic knowledge of a model dynamics. To incorporate such knowledge into a model, we propose a novel approach, fuzzy continuous Petri nets extending traditional continuous Petri net by adding new types of places and transitions called fuzzy places and fuzzy transitions. This extension makes it possible to perform fuzzy inference with fuzzy places and fuzzy transitions acting as kinetic parameters and fuzzy inference systems between input and output places, respectively.

  • PDF

Prior Exposure of Mice to Fusobacterium Nucleatum Modulates Host Response to Porphyromonas Gingivalis (Fusobacterium nucleatum 1차 면역의 Porphyromonas gingivalis 2차 면역에 대한 숙주반응 조절기능)

  • Son, Han-Yong;Kim, Sung-Jo;Choi, Jeom-Il
    • Journal of Periodontal and Implant Science
    • /
    • v.30 no.3
    • /
    • pp.675-687
    • /
    • 2000
  • Multiple periodontal pathogens sequentially colonize the subgingival niche during the conversion from gingivitis to destructive periodontal disease. An animal model of sequential immunization with key periodontal pathogens has been developed to determine whether T and B lymppocyte effector functions are skewed and fail to protect the host from pathogenic challenge. The present study was performed to evaluate immunomodulatory effect of exposure to Fusobacterium nucleatum(F. nucleatum) prior to Porphyromonas gingivalis(P. gingi - valis). Group 1(control) mice were immunized with phosphate-buffered saline, Group 2 were immunized with F. nucleatum prior to P. gingivalis, while Group 3 were immunized P. gingivalis alone. All the T cell clones derived from Group 2 demonstrated type 2 helper T cell clone(Th2 subsets), while those from Group 3 mice demonstrated Th1 subsets. Exposure of mice to F . nucleatum prior to P. gingivalis interfered with opsonophagocytosis function of sera against P. gingivalis. In adoptive T cell transfer experiments, in vivo protective capacity type 2 helper T cell clones(Th2) from Group 2 was significantly lower than type 1 helper T cell clones(Th1) from Group 3 against the lethal dose infection of P. gingivalis. Western blot analysis indicated the different pattern of recognition of P .gingivalis fimbrial proteins between sera from Group 2 and Group 3. In conclusion, these study suggest that colonization of the subgingival niche by F .nucleatum prior to the periodontal pathogen, P. gingivalis, modulates the host immune responses to P. gingivalis at humoral, cellular and molecular levels.

  • PDF

The Effector Functions of Mature T Lymphocytes Are Impaired in Transgenic Mice Expressing the SH2 Domain of TSAd/Lad

  • Choi, Youngbong;Park, Eunkyung;Ahn, Eunseon;Park, Inyoung;Yun, Yungdae
    • Molecules and Cells
    • /
    • v.28 no.3
    • /
    • pp.183-188
    • /
    • 2009
  • TSAd/Lad is a T cell adaptor molecule involved in $p56^{lck}$-mediated T cell activation. To investigate the functions of TSAd in T cells, we generated transgenic (TG) mice expressing the SH2 domain of TSAd (TSAd-SH2) under the control of the $p56^{lck}$ proximal promoter. In T cells from TSAd-SH2 TG mice, T cell receptor (TCR)-mediated early signaling events, such as $Ca^{2+}$ flux and ERK activation, were normal; however, late activation events, such as IL-2 production and proliferation, were significantly reduced. Moreover, TCR-induced cell adhesion to extracellular matrix (ECM) proteins and migration through ECM proteins were defective in T cells from TSAd-SH2 TG mice. Furthermore, the contact hypersensitivity (CHS) reaction, an inflammatory response mainly mediated by T helper 1 (Th1) cells, was inhibited in TSAd-SH2 TG mice. Taken together, these results show that TSAd, particularly the SH2 domain of TSAd, is essential for the effector functions of T cells.

Innovative and practical conditioning beverages for public health and athletic performance: Focus on immunopotentiation by lactic acid bacteria B240

  • Lee, Minchul;Kim, Kyunghee
    • Korean Journal of Exercise Nutrition
    • /
    • v.23 no.2
    • /
    • pp.13-15
    • /
    • 2019
  • [Purpose] Functional beverages are a protective or enhancing factor influencing not only public health but also athletic performance. The purpose of this study was to highlight the new conditioning beverage of the Lactobacillus pentosus strain b240 (B240) with electrolytes or proteins, which strengthens immune functions to improve the quality of life. [Methods] ISeveral related studies systematically reviews three main issues associated with conditioning beverages: (a) utilization and availability of the functional beverage; (b) significance of B240 in immune strengthening; and (c) availability and application of conditioning drinks in the daily life and sports field. [Results] Intake of B240 led to greater enhancements, including blood T-helper, NK cell, IgA and IgG level in conjunction with strengthen immune functions. These results speculated that the practical application of B240 contained beverages on physiological health and performance. [Conclusion] BODYMAINTÉ, this novel conditioning beverage is expected biological utility responsible for improved sports performance as a functional drink and has potential health-related implications.

Expression of Rotavirus Capsid Proteins VP6 and VP7 in Mammalian Cells Using Semliki Forest Virus-Based Expression System

  • Choi, Eun-Ah;Kim, Eun;Oh, Yoon-I;Shin, Kwang-Soon;Kim, Hyun-Soo;Kim, Chul-Joong
    • Journal of Microbiology and Biotechnology
    • /
    • v.12 no.3
    • /
    • pp.463-469
    • /
    • 2002
  • Rotaviruses are the world-wide leading causative agents of severe dehydrating gastroenteritis in young children and animals. The outer capsid glycoprotein VP7 and inner capsid glycoprotein VP6 of rotaviruses are highly antigenic and immunogenic. An SFV-based expression system has recently emerged as a useful tool for heterologous protein production in mammalian cells, exhibiting a much more efficient performance compared to other gene expression systems. Accordingly, the current study adopted an SFV-based expression system to express the VP7 of a group A human rotavirus from a Korean isolate, and the VP6 of a group B bovine rotavirus from a Korean isolate, in mammalian cells. The genes of the VP6 and VP7 were inserted into the SFV expression vector pSFV-1. The RNA was transcribed in vitro from pSFV-VP6 and pSFV-VP7 using SP6 polymerase. Each RNA was then electroporated into BHK-21 cells along with pSFV-helper RNA containing the structural protein gene without the packaging signal. The expression of VP6 and VP7 in the cytoplasm was then detected by immunocytochemistry. The recombinant virus was harvested by ultracentrifugation and examined under electron microscopy. After infecting BHK-21 cells with the defective viruses, the expressed proteins were separated by SDS-PAGE and analyzed by a Western blot. The results indicate that an SFV-based expression system fur the VP6 and VP7 of rotaviruses is an efficient tool for developing a diagnostic kit and/or preventive vaccine.