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Nature Communications Apr 2024The expansion of the CRISPR-Cas toolbox is highly needed to accelerate the development of therapies for genetic diseases. Here, through the interrogation of a massively...
The expansion of the CRISPR-Cas toolbox is highly needed to accelerate the development of therapies for genetic diseases. Here, through the interrogation of a massively expanded repository of metagenome-assembled genomes, mostly from human microbiomes, we uncover a large variety (n = 17,173) of type II CRISPR-Cas loci. Among these we identify CoCas9, a strongly active and high-fidelity nuclease with reduced molecular size (1004 amino acids) isolated from an uncultivated Collinsella species. CoCas9 is efficiently co-delivered with its sgRNA through adeno associated viral (AAV) vectors, obtaining efficient in vivo editing in the mouse retina. With this study we uncover a collection of previously uncharacterized Cas9 nucleases, including CoCas9, which enriches the genome editing toolbox.
Topics: Gene Editing; Humans; CRISPR-Cas Systems; Animals; Mice; Microbiota; Dependovirus; CRISPR-Associated Protein 9; RNA, Guide, CRISPR-Cas Systems; Retina; Clostridiales; HEK293 Cells; Genetic Vectors
PubMed: 38658578
DOI: 10.1038/s41467-024-47800-9 -
Signal Transduction and Targeted Therapy Apr 2024Bietti crystalline corneoretinal dystrophy is an inherited retinal disease caused by mutations in CYP4V2, which results in blindness in the working-age population, and... (Clinical Trial)
Clinical Trial
Bietti crystalline corneoretinal dystrophy is an inherited retinal disease caused by mutations in CYP4V2, which results in blindness in the working-age population, and there is currently no available treatment. Here, we report the results of the first-in-human clinical trial (NCT04722107) of gene therapy for Bietti crystalline corneoretinal dystrophy, including 12 participants who were followed up for 180-365 days. This open-label, single-arm exploratory trial aimed to assess the safety and efficacy of a recombinant adeno-associated-virus-serotype-2/8 vector encoding the human CYP4V2 protein (rAAV2/8-hCYP4V2). Participants received a single unilateral subretinal injection of 7.5 × 10 vector genomes of rAAV2/8-hCYP4V2. Overall, 73 treatment-emergent adverse events were reported, with the majority (98.6%) being of mild or moderate intensity and considered to be procedure- or corticosteroid-related; no treatment-related serious adverse events or local/systemic immune toxicities were observed. Compared with that measured at baseline, 77.8% of the treated eyes showed improvement in best-corrected visual acuity (BCVA) on day 180, with a mean ± standard deviation increase of 9.0 ± 10.8 letters in the 9 eyes analyzed (p = 0.021). By day 365, 80% of the treated eyes showed an increase in BCVA, with a mean increase of 11.0 ± 10.6 letters in the 5 eyes assessed (p = 0.125). Importantly, the patients' improvement observed using multifocal electroretinogram, microperimetry, and Visual Function Questionnaire-25 further supported the beneficial effects of the treatment. We conclude that the favorable safety profile and visual improvements identified in this trial encourage the continued development of rAAV2/8-hCYP4V2 (named ZVS101e).
Topics: Humans; Male; Female; Genetic Therapy; Middle Aged; Adult; Corneal Dystrophies, Hereditary; Dependovirus; Cytochrome P450 Family 4; Genetic Vectors; Visual Acuity; Retinal Diseases
PubMed: 38653979
DOI: 10.1038/s41392-024-01806-3 -
Molecular Biology Reports Apr 2024Adeno-associated virus (AAV) has emerged as a pivotal tool in neuroscience research, owing to its remarkable versatility and efficiency in delivering genetic material to... (Review)
Review
Adeno-associated virus (AAV) has emerged as a pivotal tool in neuroscience research, owing to its remarkable versatility and efficiency in delivering genetic material to diverse cell types within the nervous system. This mini review aims to underscore the advanced applications of AAV vectors in neuroscience and their profound potential to revolutionize our understanding of brain function and therapeutic interventions for neurological disorders. By providing a concise overview of the latest developments and strategies employing AAV vectors, this review illuminates the transformative role of AAV technology in unraveling the complexities of neural circuits and paving the way for innovative treatments. Through elucidating the multifaceted capabilities of AAV-mediated gene delivery, this review underscores its pivotal role as a cornerstone in contemporary neuroscience research, promising remarkable insights into the intricacies of brain biology and offering new avenues for therapeutic intervention.
Topics: Dependovirus; Humans; Genetic Vectors; Animals; Neurosciences; Genetic Therapy; Gene Transfer Techniques; Brain; Nervous System Diseases
PubMed: 38647711
DOI: 10.1007/s11033-024-09521-6 -
Virology Journal Apr 2024Bovine parvovirus (BPV) is an autonomous DNA virus with a smaller molecular size and subtle differences in its structural proteins, unlike other animal parvoviruses....
Stability and integrity of self-assembled bovine parvovirus virus‑like particles (BPV‑VLPs) of VP2 and combination of VP1VP2 assisted by baculovirus-insect cell expression: a potential logistical platform for vaccine deployment.
BACKGROUND
Bovine parvovirus (BPV) is an autonomous DNA virus with a smaller molecular size and subtle differences in its structural proteins, unlike other animal parvoviruses. More importantly, this virus has the potential to produce visible to silent economic catastrophes in the livestock business, despite receiving very little attention. Parvoviral virus-like particles (VLPs) as vaccines and as logistical platforms for vaccine deployment are well studied. However, no single experimental report on the role of VP1 in the assembly and stability of BPV-VLPs is available. Furthermore, the self-assembly, integrity and stability of the VLPs of recombinant BPV VP2 in comparison to VP1 VP2 Cap proteins using any expression method has not been studied previously. In this study, we experimentally evaluated the self-assembling ability with which BPV virus-like particles (VLPs) could be synthesized from a single structural protein (VP2) and by integrating both VP2 and VP1 amino acid sequences.
METHODS
In silico and experimental cloning methods were carried out. His-tagged and without-His-tag VP2 and V1VP2-encoding amino acid sequences were cloned and inserted into pFastbacdual, and insect cell-generated recombinant protein was evaluated by SDS‒PAGE and western blot. Period of infectivity and expression level were determined by IFA. The integrity and stability of the BPV VLPs were evaluated by transmission electron microscopy. The secondary structure of the BPV VLPs from both VP2 and V1VP2 was analyzed by circular dichroism.
RESULTS
Our findings show that VP2 alone was equally expressed and purified into detectable proteins, and the stability at different temperatures and pH values was not appreciably different between the two kinds of VLPs. Furthermore, BPV-VP2 VLPs were praised for their greater purity and integrity than BPV-VP1VP2 VLPs, as indicated by SDS‒PAGE. Therefore, our research demonstrates that the function of VP1 has no bearing on the stability or integrity of BPV-VLPs.
CONCLUSIONS
In summary, incredible physiochemically stable BPV VP2-derived VLPs have been found to be promising candidates for the development of multivalent vaccines and immunodiagnostic kits against enteric viruses and to carry heterogeneous epitopes for various economically important livestock diseases.
Topics: Animals; Bocavirus; Baculoviridae; Recombinant Proteins; Vaccines; Parvovirus; Capsid Proteins
PubMed: 38641833
DOI: 10.1186/s12985-024-02322-0 -
International Journal of Molecular... Mar 2024The purpose of this study was to compare the retention rate of Adeno-associated viral vector (AAV) gene therapy agents within different subretinal injection systems. The...
The purpose of this study was to compare the retention rate of Adeno-associated viral vector (AAV) gene therapy agents within different subretinal injection systems. The retention of AAV serotype 2-based voretigene neparvovec (VN) and a clinical-grade AAV serotype 8 vector within four different subretinal cannulas from two different manufacturers was quantified. A standardized qPCR using the universal inverted terminal repeats as a target sequence was developed. The instruments compared were the PolyTip cannula 25 g/38 g by MedOne Surgical, Inc., Sarasota, FL, USA, and three different subretinal injection needles by DORC, Zuidland, The Netherlands (1270.EXT Extendible 41G subretinal injection needle (23G), DORC 1270.06 23G Dual bore injection cannula, DORC 27G Subretinal injection cannula). The retention rate of VN and within the DORC products (10-28%) was comparable to the retention rate (32%) found for the PolyTip cannula that is mentioned in the FDA-approved prescribing information for VN. For the AAV8 vector, the PolyTip cannula showed a retention rate of 14%, and a similar retention rate of 3-16% was found for the DORC products (test-retest variability: mean 4.5%, range 2.5-20.2%). As all the instruments tested showed comparable retention rates, they seem to be equally compatible with AAV2- and AAV8-based gene therapy agents.
Topics: Animals; Serogroup; Drug Delivery Systems; Genetic Therapy; Dependovirus; Grasshoppers; Parvovirinae
PubMed: 38612516
DOI: 10.3390/ijms25073705 -
Scientific Reports Apr 2024Rapid and reliable detection of pathogens is crucial to complement the growing industry of mass-reared insects, in order to safeguard the insect colonies from outbreak...
Rapid and reliable detection of pathogens is crucial to complement the growing industry of mass-reared insects, in order to safeguard the insect colonies from outbreak of diseases, which may cause significant economic loss. Current diagnostic methods are mainly based on conventional PCR and microscopic examination, requiring prior knowledge of disease symptoms and are limited to identifying known pathogens. Here, we present a rapid nanopore-based metagenomics approach for detecting entomopathogens from the European house cricket (Acheta domesticus). In this study, the Acheta domesticus densovirus (AdDV) was detected from diseased individuals using solely Nanopore sequencing. Virus reads and genome assemblies were obtained within twenty-four hours after sequencing. Subsequently, due to the length of the Nanopore reads, it was possible to reconstruct significantly large parts or even the entire AdDV genome to conduct studies for genotype identification. Variant analysis indicated the presence of three AdDV genotypes within the same house cricket population, with association to the vital status of the diseased crickets. This contrast provided compelling evidence for the existence of non-lethal AdDV genotypes. These findings demonstrated nanopore-based metagenomics sequencing as a powerful addition to the diagnostic tool kit for routine pathogen surveillance and diagnosis in the insect rearing industry.
Topics: Humans; Animals; Nanopore Sequencing; Gryllidae; Densovirus; Genotype; Disease Outbreaks
PubMed: 38609404
DOI: 10.1038/s41598-024-58768-3 -
Vaccine Apr 2024Both genetic and non-genetic factors contribute to individual variation in the immune response to vaccination. Understanding how genetic background influences variation...
Both genetic and non-genetic factors contribute to individual variation in the immune response to vaccination. Understanding how genetic background influences variation in both magnitude and persistence of vaccine-induced immunity is vital for improving vaccine development and identifying possible causes of vaccine failure. Dogs provide a relevant biomedical model for investigating mammalian vaccine genetics; canine breed structure and long linkage disequilibrium simplify genetic studies in this species compared to humans. The objective of this study was to estimate the heritability of the antibody response to vaccination against viral and bacterial pathogens, and to identify genes driving variation of the immune response to vaccination in Beagles. Sixty puppies were immunized following a standard vaccination schedule with an attenuated combination vaccine containing antigens for canine adenovirus type 2, canine distemper virus, canine parainfluenza virus, canine parvovirus, and four strains of Leptospira bacteria. Serum antibody measurements for each viral and bacterial component were measured at multiple time points. Heritability estimations and GWAS were conducted using SNP genotypes at 279,902 markers together with serum antibody titer phenotypes. The heritability estimates were: (1) to Leptospira antigens, ranging from 0.178 to 0.628; and (2) to viral antigens, ranging from 0.199 to 0.588. There was not a significant difference between overall heritability of vaccine-induced immune response to Leptospira antigens compared to viral antigens. Genetic architecture indicates that SNPs of low to high effect contribute to immune response to vaccination. GWAS identified two genetic markers associated with vaccine-induced immune response phenotypes. Collectively, these findings indicate that genetic regulation of the immune response to vaccination is antigen-specific and influenced by multiple genes of small effect.
Topics: Animals; Dogs; Humans; Viral Vaccines; Genome-Wide Association Study; Pilot Projects; Antibodies, Viral; Adenoviruses, Canine; Antigens, Viral; Vaccination; Vaccines, Attenuated; Immunity; Distemper Virus, Canine; Distemper; Dog Diseases; Mammals
PubMed: 38604911
DOI: 10.1016/j.vaccine.2024.03.076 -
Lab Animal May 2024Recent genome editing techniques have substantially simplified the generation of genetically modified mice. A new study combines adeno-associated viruses (AAV) and...
Recent genome editing techniques have substantially simplified the generation of genetically modified mice. A new study combines adeno-associated viruses (AAV) and electroporation to generate a robust pipeline to deliver CRISPR-Cas reagents into mouse embryos.
Topics: Animals; CRISPR-Cas Systems; Gene Editing; Electroporation; Mice; Dependovirus
PubMed: 38600182
DOI: 10.1038/s41684-024-01363-w -
Virology Jul 2024Parvoviruses are known to be significant viral pathogens that infect a wide range of species globally. However, little is known about the parvoviruses circulating in...
Parvoviruses are known to be significant viral pathogens that infect a wide range of species globally. However, little is known about the parvoviruses circulating in Australian birds, including yellow canaries. Here, we present four parvoviral sequences including three novel parvoviruses detected from 10 yellow canaries (Crithagra flaviventris), named canary chaphamaparvovirus 1 and -2 (CaChPV1 and CaChPV2), canary dependoparvovirus 1 and -2 (CaDePV1 and CaDePV2). The whole genome sequences of CaChPV1, CaChPV2, CaDePV1, and CaDePV2 showed the highest identity with other parvoviruses at 76.4%, 75.9%, 84.0%, and 59.1%, respectively. Phylogenetic analysis demonstrated that CaChPV1 and CaChPV2 were clustered within the genus Chaphamaparvovirus. Meanwhile, CaDePV1 and CaDePV2 fall within the genus Dependoparvovirus and have the closest evolutionary relationship to the bird-associated dependoparvoviruses. Overall, this study enriched our understanding of the genetic diversity among avian parvoviruses within the Parvoviridae family.
Topics: Animals; Phylogeny; Genetic Variation; Parvoviridae Infections; Genome, Viral; Australia; Parvovirus; Bird Diseases; DNA, Viral
PubMed: 38599030
DOI: 10.1016/j.virol.2024.110081 -
Porcine Health Management Apr 2024While gilts and sows are regularly vaccinated against the porcine parvovirus (PPV), little is known on the presence of antibodies in vaccinated sows nor the decline of...
Duration of maternally derived antibodies of porcine parvovirus in growing pigs and presence of antibodies in gilts and sows vaccinated with three different parvovirus vaccines.
While gilts and sows are regularly vaccinated against the porcine parvovirus (PPV), little is known on the presence of antibodies in vaccinated sows nor the decline of maternally derived antibodies (MDA) in their offspring. On twelve farms serum samples were taken from 180 gilts and sows vaccinated at least twice with one of three different commercial PPV vaccines. On nine farms, additional 270 serum samples were collected from growing pigs of three different age categories. All 450 samples were examined for PPV antibodies (Abs) by ELISA and haemagglutination inhibition (HI) assay. In total, 65% of all gilts vaccinated twice with either vaccine 1 or vaccine 3 were seronegative by HI assay. In each farm, there were at least three animals with high Ab titres (≥ 1:1280) indicating the presence of PPV in all twelve study farms. However, PPV DNA could not be detected in collected faecal samples. While low to moderately high Ab titres (1:10-1:640) were measured in 98% of twelve-weeks-old pigs, ELISA was only positive in 30% of the same pigs. Though, the statement on the duration of MDA may depend on the applied test, we could confirm an exponential decay of MDA. In addition, we could demonstrate that applied serological tools are insufficient for the confirmation of successful vaccination.
PubMed: 38594736
DOI: 10.1186/s40813-024-00361-1