L1CAMs are immunoglobulin superfamily cell adhesion molecules that ensure proper nervous system development and function. In addition to being associated with the autism and schizophrenia spectrum disorders, mutations in the L1CAM family of genes also underlie distinct developmental syndromes with neurological conditions, such as intellectual disability, spastic paraplegia, hypotonia and congenital hydrocephalus. Studies in both vertebrate and invertebrate model organisms have established conserved neurodevelopmental roles for L1CAMs; these include axon guidance, dendrite morphogenesis, synaptogenesis, and maintenance of neural architecture, among others.
View Article and Find Full Text PDFThe emergence of genomic language models (gLMs) offers an unsupervised approach to learning a wide diversity of -regulatory patterns in the non-coding genome without requiring labels of functional activity generated by wet-lab experiments. Previous evaluations have shown that pre-trained gLMs can be leveraged to improve predictive performance across a broad range of regulatory genomics tasks, albeit using relatively simple benchmark datasets and baseline models. Since the gLMs in these studies were tested upon fine-tuning their weights for each downstream task, determining whether gLM representations embody a foundational understanding of -regulatory biology remains an open question.
View Article and Find Full Text PDFAutosomal dominant polycystic kidney disease (ADPKD) is a monogenic disorder characterized by the formation of kidney cysts that originate from the epithelial tubules of the nephron and primarily results from mutations in polycystin-1 () and polycystin-2 (). The metanephric organ culture (MOC) is an ex vivo system in which explanted embryonic kidneys undergo tubular differentiation and kidney development. MOC has been previously used to study polycystic kidney disease as treatment with 8-bromo-cAMP induces the formation of kidney cysts.
View Article and Find Full Text PDFBackground: Vascular malformations (VMs) involving the hand and forearm in children provide management challenges due to complex anatomy, indispensable functionality and developmental implications.
Methods: The institution's Vascular Registry was searched for patients with hand and arm VMs, supplemented by chart review of included patients.
Results: Twenty-one patients were identified, 52% male, with mean presenting age 5.
Despite the recent publication in March 2020 of guidelines for facial injectable treatments, the speed of the COVID-19 pandemic and its safety implications necessitate changes to these guidelines The authors described what would constitute safest practice in the provision of facial injectable treatments and summarised these in table form. Adherence to a high standard of asepsis and infectious disease precautions remain a key patient safety requirement when performing facial aesthetic injections. A revision and update of these guideline summary tables follows.
View Article and Find Full Text PDFChinese hamster ovary (CHO) cells are used for industrial production of protein-based therapeutics (i.e., "biologics").
View Article and Find Full Text PDFFor the biomanufacturing of protein biologics, establishing stable cell lines with high transgene transcription is critical for high productivity. Modern genome engineering tools can direct transgene insertion to a specified genomic locus and can potentially become a valuable tool for cell line generation. In this study, the authors survey transgene integration sites and their transcriptional activity to identify characteristics of desirable regions.
View Article and Find Full Text PDFThe Sleeping Beauty (SB) transposon system has been shown to enable long-term gene expression by integrating new sequences into host cell chromosomes. We found that the recently reported SB100x hyperactive transposase conferred a surprisingly high level of long-term expression after hydrodynamic delivery of luciferase-encoding reporter transposons in the mouse. We conducted dose-ranging studies to determine the effect of varying the amount of SB100x transposase-encoding plasmid (pCMV-SB100x) at a set dose of luciferase transposon and of varying the amount of transposon-encoding DNA at a set dose of pCMV-SB100x in hydrodynamically injected mice.
View Article and Find Full Text PDFViruses interact with various permissive and restrictive factors in host cells throughout their replication cycle. Cell lines that are non-permissive to viral infection have been particularly useful in discovering host cell proteins involved in viral life cycles. Here we describe the characterization of a human myeloid leukemia cell line, KG-1, that is resistant to infection by retroviruses and a Rhabdovirus.
View Article and Find Full Text PDFArtemis is a single-stranded endonuclease, deficiency of which results in a radiation-sensitive form of severe combined immunodeficiency (SCID-A) most effectively treated by allogeneic hematopoietic stem cell (HSC) transplantation and potentially treatable by administration of genetically corrected autologous HSCs. We previously reported cytotoxicity associated with Artemis overexpression and subsequently characterized the human Artemis promoter with the intention to provide Artemis expression that is nontoxic yet sufficient to support immunodevelopment. Here we compare the human Artemis promoter (APro) with the moderate-strength human phosphoglycerate kinase (PGK) promoter and the strong human elongation factor-1α (EF1α) promoter to regulate expression of Artemis after ex vivo lentiviral transduction of HSCs in a murine model of SCID-A.
View Article and Find Full Text PDFUnlabelled: Reverse transcriptase (RT) of human immunodeficiency virus type 1 (HIV-1) is synthesized and packaged into the virion as a part of the GagPol polyprotein. Mature RT is released by the action of viral protease. However, unlike other viral proteins, RT is subject to an internal cleavage event leading to the formation of two subunits in the virion: a p66 subunit and a p51 subunit that lacks the RNase H domain.
View Article and Find Full Text PDFThe Sleeping Beauty (SB) transposon system has been shown to mediate new gene sequence integration resulting in long-term expression. Here the effectiveness of hyperactive SB100X transposase was tested, and we found that hydrodynamic co-delivery of a firefly luciferase transposon (pT2/CaL) along with SB100X transposase (pCMV-SB100X) resulted in remarkably sustained, high levels of luciferase expression. However, after 4 weeks there was a rapid, animal-by-animal loss of luciferase expression that was not observed in immunodeficient mice.
View Article and Find Full Text PDFViruses have been used to deliver two types of site-specific nucleases into cells for targeted gene editing.
View Article and Find Full Text PDFRecombinant mammalian cells are the major hosts for the production of protein therapeutics. In addition to high expression of the product gene, a hyper-producer must also harbor superior phenotypic traits related to metabolism, protein secretion, and growth control. Introduction of genes endowing the relevant hyper-productivity traits is a strategy frequently used to enhance the productivity.
View Article and Find Full Text PDFBackground: Integration of double stranded viral DNA is a key step in the retroviral life cycle. Virally encoded enzyme, integrase, plays a central role in this reaction. Mature forms of integrase of several retroviruses (i.
View Article and Find Full Text PDFArtemis is an endonucleolytic enzyme involved in nonhomologous double-strand break repair and V(D)J recombination. Deficiency of Artemis results in a B- T- radiosensitive severe combined immunodeficiency, which may potentially be treatable by Artemis gene transfer into hematopoietic stem cells. However, we recently found that overexpression of Artemis after lentiviral transduction resulted in global DNA damage and increased apoptosis.
View Article and Find Full Text PDFTALENs are important new tools for genome engineering. Fusions of transcription activator-like (TAL) effectors of plant pathogenic Xanthomonas spp. to the FokI nuclease, TALENs bind and cleave DNA in pairs.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2011
Trinucleotide expansions cause disease by both protein- and RNA-mediated mechanisms. Unexpectedly, we discovered that CAG expansion constructs express homopolymeric polyglutamine, polyalanine, and polyserine proteins in the absence of an ATG start codon. This repeat-associated non-ATG translation (RAN translation) occurs across long, hairpin-forming repeats in transfected cells or when expansion constructs are integrated into the genome in lentiviral-transduced cells and brains.
View Article and Find Full Text PDFArtemis is a hairpin-opening endonuclease involved in nonhomologous end-joining and V(D)J recombination. Deficiency of Artemis results in radiation-sensitive severe combined immunodeficiency (SCID) characterized by complete absence of T and B cells due to an arrest at the receptor recombination stage. We have generated several lentiviral vectors for transduction of the Artemis sequence, intending to complement the deficient phenotype.
View Article and Find Full Text PDFMethods Mol Biol
February 2010
NK cell responses are regulated by a balance of inhibitory and activating signals, reflecting the net effect of interactions between receptors and ligands on target and effector cell surfaces. The identification of ligands for orphan NK cell receptors is key to enhancing our understanding of NK cell biology. Here we describe a strategy (protocol) for the identification of ligands for orphan NK cell receptors using signaling reporter cells in combination with a virus rescue system.
View Article and Find Full Text PDFBreast reconstruction using a free transverse rectus abdominis myocutaneous flap or a deep inferior epigastric perforator (DIEP) flap is a challenge in patients with a vertical midline abdominal scar due to the poor perfusion of the lower abdominal skin ellipse across the midline. In such patients, only one half of the abdominal skin ellipse can be used with certainty, and this limits the amount of tissue available for reconstructing the breast. Two cases of breast reconstruction in patients with a lower midline abdominal scar are presented using the DIEP flap, in which the poor perfusion across the midline scar was overcome by a technique of crossover anastomoses between the two deep inferior epigastric pedicles.
View Article and Find Full Text PDFThe dorsalis pedis fasciocutaneous flap has been used successfully in soft tissue reconstruction both as a pedicled and a free flap. The long-term donor site problems associated with this dorsalis pedis flap prompted us to look at the use of the dorsalis pedis fascial flap in soft tissue reconstruction. We describe the results of our anatomic study and clinical series of the use of the dorsalis pedis fascial flap both as a free flap and a pedicled flap.
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