Publications by authors named "Rennard R"

Purpose: Loss-of-function variants in the ANGPTL7 gene are associated with protection from glaucoma and reduced intraocular pressure (IOP). We investigated the role of ANGPTL7 in IOP homeostasis and its potential as a target for glaucoma therapeutics.

Methods: IOP, outflow facility, and outflow tissue morphology of Angptl7 knockout (KO) mice were assessed with and without dexamethasone (Dex).

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Antibody-targeted nanoparticles have great promise as anti-cancer drugs; however, substantial developmental challenges of antibody modules prevent many candidates from reaching the clinic. Here, we describe a robust strategy for developing an EphA2-targeting antibody fragment for immunoliposomal drug delivery. A highly bioactive single-chain variable fragment (scFv) was engineered to overcome developmental liabilities, including low thermostability and weak binding to affinity purification resins.

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Antibody-targeted nanoparticles have the potential to significantly increase the therapeutic index of cytotoxic anti-cancer therapies by directing them to tumor cells. Using antibodies or their fragments requires careful engineering because multiple parameters, including affinity, internalization rate and stability, all need to be optimized. Here, we present a case study of the iterative engineering of a single chain variable fragment (scFv) for use as a targeting arm of a liposomal cytotoxic nanoparticle.

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Although inhibition of the insulin-like growth factor (IGF) signaling pathway was expected to eliminate a key resistance mechanism for EGF receptor (EGFR)-driven cancers, the effectiveness of IGF-I receptor (IGF-IR) inhibitors in clinical trials has been limited. A multiplicity of survival mechanisms are available to cancer cells. Both IGF-IR and the ErbB3 receptor activate the PI3K/AKT/mTOR axis, but ErbB3 has only recently been pursued as a therapeutic target.

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Multispecific antibody-like molecules have the potential to advance the standard-of-care in many human diseases. The design of therapeutic molecules in this class, however, has proven to be difficult and, despite significant successes in preclinical research, only one trivalent antibody, catumaxomab, has demonstrated clinical utility. The challenge originates from the complexity of the design space where multiple parameters such as affinity, avidity, effector functions, and pharmaceutical properties need to be engineered in concurrent fashion to achieve the desired therapeutic efficacy.

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The epidermal growth factor receptor (EGFR) and the type I insulin-like growth factor receptor (IGF-1R) are two cell surface receptor tyrosine kinases known to cooperate to promote tumor progression and drug resistance. Combined blockade of EGFR and IGF-1R has shown improved anti-tumor activity in preclinical models. Here, we report the characterization of a stable IgG-like bispecific antibody (BsAb) dual-targeting EGFR and IGF-1R that was developed for cancer therapy.

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Integrin alpha6beta4 signaling interactions have been implicated in tumor progression, and beta4 expression has been linked to poor prognosis in certain breast cancer subtypes. We generated human antibodies to alpha6beta4 to further evaluate its role in tumor cell signaling. Biochemical characterization indicated these antibodies are specific for alpha6beta4, recognize distinct epitopes and have low nanomolar affinities for both human and murine protein.

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Therapeutic antibodies directed against the type 1 insulin-like growth factor receptor (IGF-1R) have recently gained significant momentum in the clinic because of preliminary data generated in human patients with cancer. These antibodies inhibit ligand-mediated activation of IGF-1R and the resulting down-stream signaling cascade. Here we generated a panel of antibodies against IGF-1R and screened them for their ability to block the binding of both IGF-1 and IGF-2 at escalating ligand concentrations (>1 microm) to investigate allosteric versus competitive blocking mechanisms.

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The TAPR locus containing the TIM gene family is implicated in the development of atopic inflammation in mouse, and TIM-1 allelic variation has been associated with the incidence of atopy in human patient populations. In this study, we show that manipulation of the TIM-1 pathway influences airway inflammation and pathology. Anti-TIM-1 mAbs recognizing distinct epitopes differentially modulated OVA-induced lung inflammation in the mouse.

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The development of asthma and other atopic diseases is influenced by cytokines produced by Th2 effector T cells. How effector T cell responses are regulated once these cell populations are established remains unclear. The recently described T cell and airway phenotype regulator locus, containing the T cell, Ig domain, mucin domain (TIM) genes, is genetically associated with Th2 cytokine production and Th2-dependent immune responses.

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Mucopolysaccharidosis type VII is a lysosomal storage disease caused by deficiency of the acid hydrolase beta-glucuronidase. MPS VII mice develop progressive lysosomal accumulation of glycosaminoglycans within multiple organs, including the brain. Using this animal model, we investigated whether gene transfer mediated by a recombinant adeno-associated virus (rAAV) type 2 vector is capable of reversing the progression of storage in adult mice.

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The Neurospora crassa mitochondrial tyrosyl-tRNA synthetase (CYT-18 protein) promotes the splicing of group I introns by helping the intron RNA fold into the catalytically active structure. The regions required for splicing include an idiosyncratic N-terminal extension, the nucleotide-binding fold domain, and the C-terminal RNA-binding domain. Here, we show that the idiosyncratic N-terminal region is in fact comprised of two functionally distinct parts: an upstream region consisting predominantly of a predicted amphipathic alpha-helix (H0), which is absent from bacterial tyrosyl-tRNA synthetases (TyrRSs), and a downstream region, which contains predicted alpha-helices H1 and H2, corresponding to features in the X-ray crystal structure of the Bacillus stearothermophilus TyrRS.

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The central nervous system (CNS) is a predominant site of involvement in several lysosomal storage diseases (LSDs); and for many patients, these diseases are diagnosed only after the onset of symptoms related to the progressive accumulation of macromolecules within lysosomes. The mucopolysaccharidosis type VII (MPS VII) mice are deficient for the lysosomal enzyme beta-glucuronidase and, by early adulthood, develop a significant degree of glycosaminoglycan storage within neuronal, glial, and leptomeningeal cells. Using this animal model, we investigated whether gene transfer mediated by a recombinant adeno-associated virus (rAAV) vector is capable of reversing the progression of storage lesions within the CNS.

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The Neurospora crassa mitochondrial tyrosyl-tRNA synthetase (CYT-18 protein) functions in splicing the N. crassa mitochondrial large rRNA intron by stabilizing the catalytically active structure of the intron core. Here, a comprehensive study of N.

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The Neurospora crassa mitochondrial tyrosyl-tRNA synthetase, the CYT-18 protein, functions in splicing group I introns by promoting the formation of the catalytically active structure of the intron RNA. The group I intron catalytic core is thought to consist of two extended helical domains, one formed by coaxial stacking of P5, P4, P6, and P6a (P4-P6 domain) and the other consisting of P8, P3, P7, and P9 (P3-P9 domain). To investigate how CYT-18 stabilizes the active RNA structure, we used an Escherichia coli genetic assay based on the phage T4 td intron to systematically test the ability of CYT-18 to compensate for structural defects in three key regions of the catalytic core: J3/4 and J6/7, connecting regions that form parts of the triple-helical-scaffold structure with the P4-P6 domain, and P7, a long-range base-pairing interaction that forms the guanosine-binding site and is part of the P3-P9 domain.

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Phenotypic switching in Wangiella dermatitidis between polarized growth processes leading to yeast budding or hyphal apical extension and nonpolarized processes leading to isotropically enlarged forms that may become multicellular is a cell-cycle related phenomenon. Exit of yeasts from the budding growth cycle by this polymorphic agent of phaeohyphomycosis can be induced by incubation of wild-type (wt) cells in pH 2.5 medium at 25 degrees C, or of certain temperature-sensitive, cell-division-cycle (cdc) mutants at pH 6.

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