Mice carrying the full-length human immunoglobulin loci produce antigen-specific human antibodies with the lambda light chain.

The development of antibody drugs through animal immunization typically requires the humanization of host antibodies to address concerns about immunogenicity in humans. However, employing an animal model capable of producing human antibodies presents the opportunity to develop antibody drugs without the need for humanization. Despite the ratio of human immunoglobulin (Ig) κ to Igλ usage being approximately 60%:40%, the majority of approved antibody therapeutics are kappa antibodies, and the development of lambda antibodies as therapeutic agents has lagged behind.

Human artificial chromosome carrying R-spondin1 and IL-22 expression cassettes in rejuvenated MSCs enhances therapeutic efficacy in ulcerative colitis model mice.

Ulcerative colitis (UC) is an incurable intestinal disease, with current treatments mainly focused on inflammation control and, in severe cases, surgical resection. Recent studies have highlighted the need for new therapies that promote tissue regeneration. R-spondin-1 (RSPO1) and interleukin-22 (IL-22) have shown anti-inflammatory and regenerative effects in UC models, but have short half-lives and poor targeting abilities.

Combination of Supramicrosurgical Lymphatico-Venular Anastomosis (sLVA) and Lymph-Sparing Liposuction in Treating Cancer-Related Lymphedema: Rationale for a Regional One-Stage Approach.

Cancer-related lymphedema represents a potential complication of cancer treatment. The aim of this study is to evaluate the effectiveness of the combination of lymphatico-venular anastomosis and liposuction in the treatment of secondary lymphedema. We present a retrospective analysis of patients affected by cancer-related unilateral limb lymphedema.

Characterization of immortalized ovarian epithelial cells with BRCA1/2 mutation.

We aimed to elucidate the mechanism underlying carcinogenesis by comparing normal and BRCA1/2-mutated ovarian epithelial cells established via Sendai virus-based immortalization. Ovarian epithelial cells (normal epithelium: Ovn; with germline BRCA1 mutation: OvBRCA1; with germline BRCA2 mutation: OvBRCA2) were infected with Sendai virus vectors carrying three immortalization genes (Bmi-1, hTERT, and SV40T). The immunoreactivity to anti-epithelial cellular adhesion molecule (EpCAM) antibodies in each cell line and cells after 25 passages was confirmed using flow cytometry.

Rapid human genomic DNA cloning into mouse artificial chromosome via direct chromosome transfer from human iPSC and CRISPR/Cas9-mediated translocation.

A 'genomically' humanized animal stably maintains and functionally expresses the genes on human chromosome fragment (hCF; <24 Mb) loaded onto mouse artificial chromosome (MAC); however, cloning of hCF onto the MAC (hCF-MAC) requires a complex process that involves multiple steps of chromosome engineering through various cells via chromosome transfer and Cre-loxP chromosome translocation. Here, we aimed to develop a strategy to rapidly construct the hCF-MAC by employing three alternative techniques: (i) application of human induced pluripotent stem cells (hiPSCs) as chromosome donors for microcell-mediated chromosome transfer (MMCT), (ii) combination of paclitaxel (PTX) and reversine (Rev) as micronucleation inducers and (iii) CRISPR/Cas9 genome editing for site-specific translocations. We achieved a direct transfer of human chromosome 6 or 21 as a model from hiPSCs as alternative human chromosome donors into CHO cells containing MAC.

Phenotypic features of dystrophin gene knockout pigs harboring a human artificial chromosome containing the entire dystrophin gene.

Mammalian artificial chromosomes have enabled the introduction of extremely large amounts of genetic information into animal cells in an autonomously replicating, nonintegrating format. However, the evaluation of human artificial chromosomes (HACs) as novel tools for curing intractable hereditary disorders has been hindered by the limited efficacy of the delivery system. We generated dystrophin gene knockout (-KO) pigs harboring the HAC bearing the entire human via a somatic cell cloning procedure (DYS-HAC-cloned pig).

Chyle leak after transposition of the aberrant left vertebral artery via 1-debranching thoracic endovascular aortic repair: a case report.

Background: Although the transposition of the aberrant left vertebral artery (ALVA) in 1-debranching thoracic endovascular aortic repair requiring zone 2 coverage for thoracic aneurysm with ALVA is reported to be an effective option, there are few reports of complications associated with the transposition of the ALVA.

Case Presentation: An 87-year-old man underwent 1-debranching thoracic endovascular repair for a saccular thoracic aortic aneurysm with the aberrant left vertebral artery. Simultaneously, the transposition of the ALVA was performed to prevent cerebral complications because the left vertebral artery was dominant.

Full-length human dystrophin on human artificial chromosome compensates for mouse dystrophin deficiency in a Duchenne muscular dystrophy mouse model.

Dystrophin maintains membrane integrity as a sarcolemmal protein. Dystrophin mutations lead to Duchenne muscular dystrophy, an X-linked recessive disorder. Since dystrophin is one of the largest genes consisting of 79 exons in the human genome, delivering a full-length dystrophin using virus vectors is challenging for gene therapy.

Analysis of in vitro and in vivo metabolism of zidovudine and gemfibrozil in trans-chromosomic mouse line expressing human UGT2 enzymes.

UDP-glucuronosyltransferases (UGTs) catalyze the conjugation of various substrates with sugars. Since the UGT2 family forms a large cluster spanning 1.5 Mb, transgenic mouse lines carrying the entire human UGT2 family have not been constructed because of limitations in conventional cloning techniques.

Metabolic Disposition of Triazolam and Clobazam in Humanized CYP3A Mice with a Double-Knockout Background of Mouse and Genes.

Knockout (KO) of mouse genes increases the expression of hepatic CYP2C enzymes, which can metabolize triazolam, a typical substrate of human CYP3A. There is still marked formation of 1'-hydroxytriazolam in Cyp3a-KO (3aKO) mice after triazolam dosing. Here, we generated a new model of humanized CYP3A (hCYP3A) mice with a double-KO background of and genes (2c3aKO), and we examined the metabolic profiles of triazolam in wild-type (WT), 2c3aKO, and hCYP3A/2c3aKO mice and studies using liver microsomes showed that the formation of 1'-hydroxytriazolam in 2c3aKO mice was less than 8% of that in WT mice.

Influence of MDR1 gene polymorphism (2677G>T) on expression and function of P-glycoprotein at the blood-brain barrier: utilizing novel P-glycoprotein humanized mice with mutation.

P-glycoprotein, the encoded product of the MDR1 / ABCB1 gene in humans, is expressed in numerous tissues including brain capillary endothelial cells and restricts the distribution of xenobiotics into the brain as an efflux pump. Although a large number of single nucleotide polymorphisms in the MDR1 gene have been identified, the influence of the nonsynonymous 2677G>T/A single nucleotide polymorphism on P-glycoprotein at the blood-brain barrier has remained unclear. In the present study, we developed a novel P-glycoprotein humanized mouse line carrying the 2677G>T mutation by utilizing a mouse artificial chromosome vector constructed by genetic engineering technology and we evaluated the influence of 2677G>T on the expression and function of P-glycoprotein at the blood-brain barrier in vivo .

Open-wedge osteotomy for thumb radial angulation in Apert syndrome using a bone-graft substitute.

A short thumb with radial angulation causes loss of hand function in patients with Apert syndrome. Although past reports have described various procedures for the correction of the thumb, there has been no consensus on the best procedure. This study aimed to assess the clinical and radiographic results of a surgical technique for the correction of a thumb radial angulation deformity: open-wedge osteotomy using a bone-graft substitute.

Thoracic Outlet Syndrome with Subclavian Artery Thrombosis Caused by Synostosis of the First and Second Ribs: A Case Report.

Case: A 43-year-old woman presented with pain, paresthesia, and coldness of the right upper extremity suggestive of the diagnosis of thoracic outlet syndrome. Three-dimensional computed tomography angiography revealed that the right subclavian artery was constricted because it traveled over an abnormal first rib. After anticoagulation and antithrombotic therapy, the patient underwent resection of the abnormal first rib.

Efficient human-like antibody repertoire and hybridoma production in trans-chromosomic mice carrying megabase-sized human immunoglobulin loci.

Trans-chromosomic (Tc) mice carrying mini-chromosomes with megabase-sized human immunoglobulin (Ig) loci have contributed to the development of fully human therapeutic monoclonal antibodies, but mitotic instability of human mini-chromosomes in mice may limit the efficiency of hybridoma production. Here, we establish human antibody-producing Tc mice (TC-mAb mice) that stably maintain a mouse-derived, engineered chromosome containing the entire human Ig heavy and kappa chain loci in a mouse Ig-knockout background. Comprehensive, high-throughput DNA sequencing shows that the human Ig repertoire, including variable gene usage, is well recapitulated in TC-mAb mice.

Bipedicled digital artery perforator volar adiposal turned-over flap for reconstruction of transverse fingertip amputation.

Different approaches to fingertip reconstructions are reported for cases in which microsurgical replantation is impossible. This report presents two cases of bipedicled digital artery perforator adiposal flaps for fingertip reconstruction after traumatic amputations. Adiposal flaps, including the radial and ulnar digital artery perforator vessels proximal to the distal interphalangeal joint, were elevated and turned to cover the fingertip defect.

Divergent Dislocation of the Elbow in an Adult with Ehlers-Danlos Syndrome: A Case Report.

Case: A 32-year-old man with Ehlers-Danlos syndrome (EDS) fell while snowboarding and injured his right elbow. Radiography revealed a posterior dislocation of the elbow and a proximal radioulnar joint dislocation. A diagnosis of transverse divergent dislocation of the elbow was established.

A transchromosomic rat model with human chromosome 21 shows robust Down syndrome features.

Progress in earlier detection and clinical management has increased life expectancy and quality of life in people with Down syndrome (DS). However, no drug has been approved to help individuals with DS live independently and fully. Although rat models could support more robust physiological, behavioral, and toxicology analysis than mouse models during preclinical validation, no DS rat model is available as a result of technical challenges.

Construction of stable mouse artificial chromosome from native mouse chromosome 10 for generation of transchromosomic mice.

Mammalian artificial chromosomes derived from native chromosomes have been applied to biomedical research and development by generating cell sources and transchromosomic (Tc) animals. Human artificial chromosome (HAC) is a precedent chromosomal vector which achieved generation of valuable humanized animal models for fully human antibody production and human pharmacokinetics. While humanized Tc animals created by HAC vector have attained significant contributions, there was a potential issue to be addressed regarding stability in mouse tissues, especially highly proliferating hematopoietic cells.

Blastocyst complementation using Prdm14-deficient rats enables efficient germline transmission and generation of functional mouse spermatids in rats.

Murine animal models from genetically modified pluripotent stem cells (PSCs) are essential for functional genomics and biomedical research, which require germline transmission for the establishment of colonies. However, the quality of PSCs, and donor-host cell competition in chimeras often present strong barriers for germline transmission. Here, we report efficient germline transmission of recalcitrant PSCs via blastocyst complementation, a method to compensate for missing tissues or organs in genetically modified animals via blastocyst injection of PSCs.

Engineering of human induced pluripotent stem cells via human artificial chromosome vectors for cell therapy and disease modeling.

Genetic engineering of induced pluripotent stem cells (iPSCs) holds great promise for gene and cell therapy as well as drug discovery. However, there are potential concerns regarding the safety and control of gene expression using conventional vectors such as viruses and plasmids. Although human artificial chromosome (HAC) vectors have several advantages as a gene delivery vector, including stable episomal maintenance and the ability to carry large gene inserts, the full potential of HAC transfer into iPSCs still needs to be explored.

Development of Caco-2 cells expressing four CYPs via a mammalian artificial chromosome.

Background: Oral administration is the most common way to deliver drugs to the systemic circulation or target organs. Orally administered drugs are absorbed in the intestine and metabolized in the intestine and liver. In the early stages of drug development, it is important to predict first-pass metabolism accurately to select candidate drugs with high bioavailability.

Clinical results of splinting versus observation for pediatric trigger thumb.

Patients with pediatric trigger thumb present with fixed contracture of the interphalangeal joint (IPJ) or snapping of the thumb. We applied a hand-based dynamic splint using coils at the IPJ. The aim of this study was to report the clinical outcomes of splint therapy versus observation.

A non-mosaic transchromosomic mouse model of down syndrome carrying the long arm of human chromosome 21.

Animal models of Down syndrome (DS), trisomic for human chromosome 21 (HSA21) genes or orthologs, provide insights into better understanding and treatment options. The only existing transchromosomic (Tc) mouse DS model, Tc1, carries a HSA21 with over 50 protein coding genes (PCGs) disrupted. Tc1 is mosaic, compromising interpretation of results.