Expression of active human beta-glucuronidase in Sf9 cells infected with recombinant baculovirus

Development and Evaluation of a Shrimp Virus (IHHNV)-Mediated Gene Transfer and Expression System for Shrimps

An efficient gene transfer and expression tool is lacking for shrimps and shrimp cells. To solve this, this study has developed a shrimp DNA virus-mediated gene transfer and expression system, consisting of insect Sf9 cells for viral packaging, the shrimp viral vector of pUC19-IHHNV-PH-GUS and the baculoviral vector of Bacmid or Bacmid-VP28 encoding the shrimp WSSV envelope protein VP28. The pUC19-IHHNV-PH-GUS vector was constructed by assembling the genomic DNA of shrimp infectious hypodermal and hematopoietic necrosis virus (IHHNV), which has shortened inverted terminal repeats, into a pUC19 backbone, and then an expression cassette of baculoviral polyhedron (PH) promoter-driven GUS (β-glucuronidase) reporter gene was inserted immediately downstream of IHHNV for proof-of-concept. It was found that the viral vector of pUC19-IHHNV-PH-GUS could be successfully packaged into IHHNV-like infective virions in the Sf9 cells, and the gene transfer efficiency of this system was evaluated and verified in three systems of Sf9 cells, shrimp hemolymph cells and tissues of infected shrimps, but the GUS expression could only be detected in cases where the viral vector was co-transfected or co-infected with a baculovirus of Bacmid or Bacmid-VP28 due to the Bacmid-dependence of the PH promoter. Moreover, the packaging and infection efficiencies could be significantly improved when Bacmid-VP28 was used instead of Bacmid.

Lysosomal enzyme replacement therapies: Historical development, clinical outcomes, and future perspectives

Lysosomes and lysosomal enzymes play a central role in numerous cellular processes, including cellular nutrition, recycling, signaling, defense, and cell death. Genetic deficiencies of lysosomal components, most commonly enzymes, are known as "lysosomal storage disorders" or "lysosomal diseases" (LDs) and lead to lysosomal dysfunction. LDs broadly affect peripheral organs and the central nervous system (CNS), debilitating patients and frequently causing fatality. Among other approaches, enzyme replacement therapy (ERT) has advanced to the clinic and represents a beneficial strategy for 8 out of the 50-60 known LDs. However, despite its value, current ERT suffers from several shortcomings, including various side effects, development of "resistance", and suboptimal delivery throughout the body, particularly to the CNS, lowering the therapeutic outcome and precluding the use of this strategy for a majority of LDs. This review offers an overview of the biomedical causes of LDs, their socio-medical relevance, treatment modalities and caveats, experimental alternatives, and future treatment perspectives.

Properties and structures of β-glucuronidases with different transformation types of glycyrrhizin

Substrate recognition mechanisms of three fungi β-glucuronidases with different types of GL hydrolysis were analyzed.

α-Fucosidase as a novel convenient biomarker for cellular senescence

Due to its role in aging and antitumor defense, cellular senescence has recently attracted increasing interest. However, there is currently no single specific marker that can unequivocally detect senescent cells. Here, we identified α-L-fucosidase (α-Fuc) as a novel sensitive biomarker for cellular senescence. Regardless of the stress stimulus and cell type, α-Fuc activity was induced in all canonical types of cellular senescence, including replicative, DNA damage- and oncogene-induced senescence. Strikingly, in most models the degree of α-Fuc upregulation was higher than the induction of senescence-associated β-galactosidase (SA-β-Gal), the current gold standard for senescence detection. As α-Fuc is convenient and easy to measure, we suggest its utility as a valuable marker, in particular in cells with low SA-β-Gal activity.

Construction and expression of fusion gene of single chain Fv against human colorectal carcinoma

AIM: To explore the construction of the fusion gene of recombinant ND-1scFv against human colorectal carcinoma and yeast cytosine deaminase and the expression of the fusion protein in E. coli.

METHODS: Yeast cytosine deaminase gene was fused with the 3'terminus of gene of ND-1scFv against human colorectal carcinoma by a 18 bp linker with sequences encoding GSGGSG. To construct ND-1scFv-CD gene, plasmid pET 28 a(+)-ND-1scFv-CD was transformed into E. coli BL-21, and induced by IPTG to express the ND-1scFv-CD fusion protein. The expressed product was purified by affinity chromatography using NI-NTA resin, and its immunity was analyzed by ELISA. The cytotoxic activity of the ADEPT system containing ND-1 scFv-CD/5FC against human colon carcinoma cell line was evaluated by MTT assay.

RESULTS: Sequencing results showed that the ND-1scFv-CD gene consisted of 1 269 bp, including ND-1scFv 732 bp and CD 477 bp. SDS-PAGE analysis showed that the expected molecular weight of fusion protein was 47 Kd. Optical density scanning showed that fusion protein expressed in E. coli accounted to 27% of the total bacterial proteins. ELISA analysis revealed that ND-1scFv-CD reserved similar immunity of ND-1scFv. MTT assay showed scFv-CD/5FC was cytotoxic to human colorectal carcinoma cells.

CONCLUSION: ND-1scFv-CD gene against human colorectal carcinoma was constructed and expressed successfully in E. coli. The fusion protein exhibited good immunity and enzymatic activity.