Publications by authors named "Nobuhiko Kamoshita"

Article Synopsis
  • Genetic diagnosis is crucial for hemophilia patients, but some still have unidentified mutations; this study focused on a new approach using induced pluripotent stem cells (iPSCs) to investigate hemophilia A.
  • Researchers analyzed siblings with moderate hemophilia, found a deep intronic variant in the F8 gene that likely disrupts splicing, leading to abnormal mRNA and reduced factor VIII production.
  • The study successfully used genome editing to correct the splicing issue, restoring F8 mRNA and factor VIII production, demonstrating the potential of personalized gene therapy in treating hemophilia.
View Article and Find Full Text PDF
Article Synopsis
  • * Intravenous injection of AAV.GT5 resulted in similar liver transduction in both humanized mice and macaques, but it had a low recovery and short half-life due to its positive charge affecting blood interactions.
  • * Enhanced liver transduction was achieved by administering AAV.GT5 directly into the liver, and unlike AAV-Spark100, AAV.GT5 showed a lower tendency to generate neutralizing antibodies, suggesting it
View Article and Find Full Text PDF

Background: Base editing via CRISPR-Cas9 has garnered attention as a method for correcting disease-specific mutations without causing double-strand breaks, thereby avoiding large deletions and translocations in the host chromosome. However, its reliance on the protospacer adjacent motif (PAM) can limit its use. We aimed to restore a disease mutation in a patient with severe hemophilia B using base editing with SpCas9-NG, a modified Cas9 with the board PAM flexibility.

View Article and Find Full Text PDF

Background: Intravenous administration of adeno-associated virus (AAV) vectors is a promising gene therapy approach for monogenic diseases. However, re-administration of the same AAV serotype is impossible because of the induction of anti-AAV neutralizing antibodies (NAbs). Here, we examined the feasibility of re-administrating AAV vector serotypes different from the initial AAV vector serotype.

View Article and Find Full Text PDF

Adeno-associated virus (AAV) vectors are promising modalities of gene therapy to address unmet medical needs. However, anti-AAV neutralizing antibodies (NAbs) hamper the vector-mediated therapeutic effect. Therefore, NAb prevalence in the target population is vital in designing clinical trials with AAV vectors.

View Article and Find Full Text PDF

Most gene therapy clinical trials that systemically administered adeno-associated virus (AAV) vector enrolled only patients without anti-AAV-neutralizing antibodies. However, laboratory tests to measure neutralizing antibodies varied among clinical trials and have not been standardized. In this study, we attempted to improve the sensitivity and reproducibility of a cell-based assay to detect neutralizing antibodies and to determine the detection threshold to predict treatment efficacy.

View Article and Find Full Text PDF
Article Synopsis
  • Platelet function tests are used to evaluate how platelets activate outside the body, but variability among individuals makes standardization challenging.
  • The study created a specific cell line to better understand platelet activation by analyzing different megakaryoblastic cell lines and confirming key signaling pathways.
  • The research developed a method to effectively monitor calcium mobilization in these cells using a sensitive indicator, paving the way for potential drug screening and diagnosis related to platelet activity disorders.
View Article and Find Full Text PDF

IκBζ (encoded by the ) is a member of the nuclear IκB family, which is involved in the expression of secondary response genes based on signals from TLR or IL-1R. ST2L, an IL-33R, is a member of the IL-1R family and abundantly expressed in tissue-resident immune cells, such as mast cells and innate lymphoid cells; however, its downstream signaling pathway remains unelucidated. In this study, we examined the role of IκBζ in ST2L-mediated cytokine and chemokine production in mast cells.

View Article and Find Full Text PDF

The translation of capsid proteins of Plautia stali intestine virus (PSIV), encoded in its second open reading frame (ORF2), is directed by an internal ribosomal entry site (IRES) located in the intergenic region (IGR). Owing to the specific properties of PSIV IGR in terms of nucleotide length and frame organization, capsid proteins are also translated via stop codon readthrough in mammalian cultured cells as an extension of translation from the first ORF (ORF1) and IGR. To delineate stop codon readthrough in PSIV, we determined requirements of -acting elements through a molecular genetics approach applied in both cell-free translation systems and cultured cells.

View Article and Find Full Text PDF

Translation initiation of the second ORF of insect dicistrovirus RNA depends on an internal ribosomal entry site (IRES) in its intergenic region (IGR) and is exceptional in using a codon other than AUG and in not using the canonical initiator methionine tRNA. Studies in vitro suggest that pseudoknot I (PKI) immediately preceding the initiation codon occupies the ribosomal P site and that an elongator tRNA initiates translation from the ribosomal A site. Using dicistronic reporters carrying mutations in the initiation codon of the second ORF and mutant elongator or initiator tRNAs capable of reading these codons, we provide direct evidence for initiation from the A site in mammalian cells and, under certain conditions, also from the P site.

View Article and Find Full Text PDF

Nucleotides (nt) 108 to 742 of an infectious cDNA clone of poliovirus (PV) Mahoney strain, including the corresponding region of the internal ribosome entry site (IRES), was replaced by nt 28 to 710 of hepatitis C virus (HCV) cDNA corresponding to the whole HCV IRES. A chimeric PV (2A-369) was generated by transfecting mammalian cells with an RNA transcribed in vitro from the cDNA. To examine replicating capacity of virus 2A-369 in the brain and liver of a mouse model for poliomyelitis, a new mouse model (MPVRTg25-61) that is transgenic for human PV receptor (hPVR; CD155) was generated in order to obtain a higher expression level of hPVR in the liver than those of hPVRTg mouse lines generated by us so far.

View Article and Find Full Text PDF

Translation initiation of poliovirus and hepatitis C virus (HCV) RNA occurs by entry of ribosomes to the internal RNA sequence, called the internal ribosomal entry site (IRES). Both IRES bind to the La protein and are thought to require the protein for their translation initiation activity, although they are greatly different in both the primary and predicted secondary structures. To compare the La protein requirement for these IRES, we took advantage of I-RNA from the yeast Saccharomyces cerevisiae, which has been reported to bind to La protein and block poliovirus IRES-mediated translation initiation.

View Article and Find Full Text PDF