We recently reported that resistance to PD-1 blockade in a refractory lung cancer-derived model involved increased collagen deposition and the collagen-binding inhibitory receptor leukocyte-associated immunoglobulin-like receptor 1 (LAIR1). Thus, we hypothesized that LAIR1 and collagen cooperated to suppress therapeutic response. In this study, we report that LAIR1 is associated with tumor stroma and is highly expressed by intratumoral myeloid cells in both human tumors and mouse models of cancer.
View Article and Find Full Text PDFSolid tumors are dense three-dimensional (3D) multicellular structures that enable efficient receptor-ligand trans interactions via close cell-cell contact. Immunoglobulin-like transcript (ILT)2 and ILT4 are related immune-suppressive receptors that play a role in the inhibition of myeloid cells within the tumor microenvironment. The relative contribution of ILT2 and ILT4 to immune inhibition in the context of solid tumor tissue has not been fully explored.
View Article and Find Full Text PDFDuring endochondral ossification, chondrocytes secrete a proteoglycan (PG)-rich extracellular matrix that can inhibit the process of cartilage maturation, including expression of Ihh and Col10a1. Because bone morphogenetic proteins (BMPs) can promote cartilage maturation, we hypothesized that cartilage PGs normally inhibit BMP signalling. Accordingly, BMP signalling was evaluated in chondrocytes of wild-type and PG mutant (fam20b-/-) zebrafish and inhibited with temporal control using the drug DMH1 or an inducible dominant-negative BMP receptor transgene (dnBMPR).
View Article and Find Full Text PDFBackground Alloimmunization of erythrocytes is a major problem in patients with hematological diseases that require frequent blood transfusions. Matching of extended red cell antigens of Kell, MNS, Kidd, and Duffy can decrease the risk of alloimmunization. Hence, in this study, the frequencies of the extended red cell phenotypes were explored.
View Article and Find Full Text PDFAncestors of the Antarctic icefishes (family Channichthyidae) were benthic and had no swim bladder, making it energetically expensive to rise from the ocean floor. To exploit the water column, benthopelagic icefishes were hypothesized to have evolved a skeleton with "reduced bone," which gross anatomical data supported. Here, we tested the hypothesis that changes to icefish bones also occurred below the level of gross anatomy.
View Article and Find Full Text PDFComput Methods Programs Biomed
June 2021
Background And Objective: Some types of cancer cause rapid cell growth, while others cause cells to grow and divide at a slower rate. Certain forms of cancer result in visible growths called tumors. This work proposes an inverse estimation of the size and location of the tumor using a feedforward Neural Network (FFNN) model.
View Article and Find Full Text PDFCortical bone porosity is intimately linked with remodeling, is of growing clinical interest, and is increasingly accessible by imaging. Thus, the potential of animal models of osteoporosis (OP) to provide a platform for studying how porosity develops and responds to interventions is tremendous. To date, rabbit models of OP have largely focused on trabecular microarchitecture or bone density; some such as ovariectomy (OVX) have uncertain efficacy and cortical porosity has not been extensively reported.
View Article and Find Full Text PDFSoluble guanylate cyclase (sGC) is a key enzyme implicated in various physiological processes such as vasodilation, thrombosis and platelet aggregation. The enzyme's Heme-Nitric oxide/Oxygen (H-NOX) binding domain is the only sensor of nitric oxide (NO) in humans, which on binding with NO activates sGC to produce the second messenger cGMP. H-NOX is thus a hot target for drug design programs.
View Article and Find Full Text PDFThe lacunar-canalicular network (LCN) of bone contains osteocytes and their dendritic extensions, which allow for intercellular communication, and are believed to serve as the mechanosensors that coordinate the processes of bone modeling and remodeling. Imbalances in remodeling, for example, are linked to bone disease, including fragility associated with aging. We have reported that there is a reduction in scale for one component of the LCN, osteocyte lacunar volume, across the human lifespan in females.
View Article and Find Full Text PDFRetinoic acid (RA) signaling is necessary for proper patterning and morphogenesis during embryonic development. Tissue-specific RA signaling requires precise spatial and temporal synthesis of RA from retinal by retinaldehyde dehydrogenases (Raldh) and the conversion of retinol to retinal by retinol dehydrogenases (Rdh) of the short-chain dehydrogenase/reducatase gene family (SDR). The SDR, retinol dehydrogenase 10 (RDH10), is a major contributor to retinal biosynthesis during mid-gestation.
View Article and Find Full Text PDFThe mechanisms by which ethanol and inhaled anesthetics influence the nervous system are poorly understood. Here we describe the positional cloning and characterization of a new mouse mutation isolated in an N-ethyl-N-nitrosourea (ENU) forward mutagenesis screen for animals with enhanced locomotor activity. This allele, Lightweight (Lwt), disrupts the homolog of the Caenorhabditis elegans (C.
View Article and Find Full Text PDFPrecise control of neuronal migration is essential for proper function of the brain. Taking a forward genetic screen, we isolated a mutant mouse with defects in interneuron migration. By genetic mapping, we identified a frame shift mutation in the pericentrin (Pcnt) gene.
View Article and Find Full Text PDFRegulatory factor X (Rfx) homologs regulate the transcription of genes necessary for ciliogenesis in invertebrates and vertebrates. Primary cilia are necessary for Hedgehog signaling and regulation of the activity of the transcriptional regulators known as Gli proteins, which are targets of Hedgehog signaling. Here, we describe an Rfx4(L298P) mouse mutant with distinct dorsoventral patterning defects in the ventral spinal cord and telencephalon due to aberrant Sonic hedgehog (Shh) signaling and Gli3 activity.
View Article and Find Full Text PDFExtrinsic signals controlling generation of neocortical neurons during embryonic life have been difficult to identify. In this study we demonstrate that the dorsal forebrain meninges communicate with the adjacent radial glial endfeet and influence cortical development. We took advantage of Foxc1 mutant mice with defects in forebrain meningeal formation.
View Article and Find Full Text PDFPrecise regulation of Wnt signaling is important in many contexts, as in development of the vertebrate forebrain, where excessive or ectopic Wnt signaling leads to severe brain defects. Mutation of the widely expressed oto gene causes loss of the anterior forebrain during mouse embryogenesis. Here we report that oto is the mouse ortholog of the gpi deacylase gene pgap1, and that the endoplasmic reticulum (ER)-resident Oto protein has a novel and deacylase-independent function during Wnt maturation.
View Article and Find Full Text PDFDisruption or improper activation of the Hedgehog (Hh) pathway is associated with developmental abnormalities and cancer. Although characterized in Drosophila, the mechanisms that mediate the Hh signal downstream of the Smoothened (Smo) seven-transmembrane protein in vertebrates remain poorly understood. In particular, the Fused (Fu) kinase, which mediates Hh signaling in flies, is dispensable in mammals.
View Article and Find Full Text PDFRACK1 is a multifunctional scaffolding protein known to be involved in the regulation of various signaling cascades in the central nervous system (CNS). In order to gain insight into the neurological functions of RACK1, we examined the expression of RACK1 mRNA and protein during gestation and in the adult mouse brain. Several expression patterns were observed.
View Article and Find Full Text PDFInterleukin-1alpha (IL-1alpha) is a powerful activator of osteoclast cells. However, the underlying mechanism for this activation is unknown. In this study, we reveal that IL-1alpha up-regulates the expression of cathepsin K protein, a key protease in bone resorption, by five-fold.
View Article and Find Full Text PDFStriking conservation in various organisms suggests that cellular nucleic acid-binding protein (CNBP) plays a fundamental biological role across different species. However, the regulated expression and physiological properties of the CNBP gene are unknown. In this study, we report the molecular cloning, promoter characterization, developmental expression and functional analysis of the mouse CNBP gene.
View Article and Find Full Text PDFMouse mutants have allowed us to gain significant insight into axis development. However, much remains to be learned about the cellular and molecular basis of early forebrain patterning. We describe a lethal mutation mouse strain generated using promoter-trap mutagenesis.
View Article and Find Full Text PDFBone morphogenetic proteins (BMPs) signal via complexes of type I and type II receptors. In this study, we mapped the expression of type IA, type IB and type II receptors during craniofacial chondrogenesis and then perturbed receptor function in vivo with retroviruses expressing dominant-negative or constitutively active type I receptors. BmprIB was the only receptor expressed within all cartilages.
View Article and Find Full Text PDFEmbryonic facial development in chick embryos involves a sequential activation of genes that control differential growth and patterning of the beak. In the present study we isolate one such gene, the transcription factor, AP-2, that is known to be expressed in the face of mouse embryos. The protein sequence of chick AP-2alpha is 94% homologous to human and mouse AP-2.
View Article and Find Full Text PDFThe in vitro antitumor activities of the nucleoside analogs, 2-chlorodeoxyadenosine (CdA) and 9-beta-arabinosyl-2-fluoroadenine monophosphate (Flu), and the alkylating agent, chlorambucil (CLB), were compared in leukemic cells from 28 patients with chronic lymphocytic leukemia (CLL). On a molar basis, the median sensitivities of the cells to these agents were CLB > CdA > Flu. CLL cells from 90% of the patients had similar relative orders of sensitivities to CdA and Flu, while cells from 10% of the patients showed differential sensitivities to these agents.
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