oral-intubation-adult-zebrafish-model-for-evaluating-intestinal

Oral Intubation of Adult Zebrafish: A Model for Evaluating Intestinal Uptake of Bioactive Compounds

Most pathogens invade organisms through their mucosa. This is particularly true in fish as they are continuously exposed to a microbial-rich water ...

Universitat Autònoma de Barcelona

Canine adenovirus type 2 vectors (CAV-2) are promising tools to treat global central nervous system (CNS) disorders because of their preferential transduction of neurons and efficient retrograde axonal transport. Here we tested the potential of a helper-dependent CAV-2 vector expressing β-glucuronidase (HD-RIGIE) in a mouse model of mucopolysaccharidosis type VII (MPS VII), a lysosomal storage disease caused by deficiency in β-glucuronidase activity. MPS VII leads to glycosaminoglycan accumulation into enlarged vesicles in peripheral tissues and the CNS, resulting in peripheral and neuronal dysfunction. After intracranial administration of HD-RIGIE, we show long-term expression of β-glucuronidase that led to correction of neuropathology around the injection site and in distal areas. This phenotypic correction correlated with a decrease in secondary-elevated lysosomal enzyme activity and glycosaminoglycan levels, consistent with global biochemical correction. Moreover, HD-RIGIE-treated mice show significant cognitive improvement. Thus, injections of HD-CAV-2 vectors in the brain allow a global and sustained expression and may have implications for brain therapy in patients with lysosomal storage disease.

Central nervous system delivery of helper-dependent canine adenovirus corrects neuropathology and behavior in mucopolysaccharidosis type VII mice.

In the search for an eminently practical strategy to develop immunostimulants and vaccines for farmed fish, we have devised recombinant viral antigens presented as "nanopellets" (NPs). These are inclusion bodies of fish viral antigenic proteins produced in . Soluble recombinant proteins are too labile to endure the  environment and maintain full functionality, and therefore require encapsulation strategies. Yet when they are produced as nanostructures, they can withstand the wide range of gastrointestinal pH found in fish, high temperatures, and lyophilization. Moreover, these nanomaterials are biologically active, non-toxic to fish, cost-effective regarding production and suitable for oral administration. Here, we present three versions of NPs formed by antigenic proteins from relevant viruses affecting farmed fish: the viral nervous necrosis virus coat protein, infectious pancreatic necrosis virus viral protein 2, and a viral haemorrhagic septicemia virus G glycoprotein fragment. We demonstrate that the nanoparticles are taken up  by zebrafish ZFL cells and  by intubating zebrafish as a proof of concept for oral delivery. Encouragingly, analysis of gene expression suggests these NPs evoke an antiviral innate immune response in ZFL cells and in rainbow trout head kidney macrophages. They are therefore a promising platform for immunostimulants and may be candidates for vaccines should protection be demonstrated.

Rosemary Thwaite

Institute of Biotechnology and Biomedicine (IBB-UAB),
Department of Cell Biology,
Animal Physiology and Immunology,
Department of Cell Biology, Animal Physiology and Immunology

Universitat Autònoma de Barcelona

Oral Intubation of Adult Zebrafish: A Model for Evaluating Intestinal Uptake of Bioactive Compounds

Rosemary Thwaite

Institute of Biotechnology and Biomedicine (IBB-UAB),Department of Cell Biology,Animal Physiology and Immunology,Department of Cell Biology, Animal Physiology and Immunology

Universitat Autònoma de Barcelona

Oral Intubation of Adult Zebrafish: A Model for Evaluating Intestinal Uptake of Bioactive Compounds

Institute of Biotechnology and Biomedicine (IBB-UAB),
Department of Cell Biology,
Animal Physiology and Immunology,
Department of Cell Biology, Animal Physiology and Immunology