An optimized IL-12-Fc expands its therapeutic window, achieving strong activity against mouse tumors at tolerable drug doses.

Background: Interleukin-12 (IL-12) has emerged as one of the most potent cytokines for tumor immunotherapy due to its ability to induce interferon γ (IFNγ) and polarize Th1 responses. Clinical use of IL-12 has been limited by a short half-life and narrow therapeutic index.

Methods: We generated a monovalent, half-life-extended IL-12-Fc fusion protein, mDF6006, engineered to retain the high potency of native IL-12 while significantly expanding its therapeutic window.

Protecting boreal caribou habitat can help conserve biodiversity and safeguard large quantities of soil carbon in Canada.

Boreal caribou require large areas of undisturbed habitat for persistence. They are listed as threatened with the risk of extinction in Canada because of landscape changes induced by human activities and resource extraction. Here we ask: Can the protection of habitat for boreal caribou help Canada meet its commitments under the United Nations Convention on Biological Diversity and United Nations Framework Convention on Climate Change? We identified hotspots of high conservation value within the distribution of boreal caribou based on: (1) three measures of biodiversity for at risk species (species richness, unique species and taxonomic diversity); (2) climate refugia or areas forecasted to remain unchanged under climate change; and, (3) areas of high soil carbon that could add to Canada's greenhouse gas emissions if released into the atmosphere.

Multi-objective optimization can balance trade-offs among boreal caribou, biodiversity, and climate change objectives when conservation hotspots do not overlap.

The biodiversity and climate change crises have led countries-including Canada-to commit to protect more land and inland waters and to stabilize greenhouse gas concentrations. Canada is also obligated to recover populations of at-risk species, including boreal caribou. Canada has the opportunity to expand its protected areas network to protect hotspots of high value for biodiversity and climate mitigation.

A trispecific antibody targeting HER2 and T cells inhibits breast cancer growth via CD4 cells.

Effective antitumour immunity depends on the orchestration of potent T cell responses against malignancies. Regression of human cancers has been induced by immune checkpoint inhibitors, T cell engagers or chimeric antigen receptor T cell therapies. Although CD8 T cells function as key effectors of these responses, the role of CD4 T cells beyond their helper function has not been defined.

Human-relevant mechanisms and risk factors for TAK-875-Induced liver injury identified via a gene pathway-based approach in Collaborative Cross mice.

Development of TAK-875 was discontinued when a small number of serious drug-induced liver injury (DILI) cases were observed in Phase 3 clinical trials. Subsequent studies have identified hepatocellular oxidative stress, mitochondrial dysfunction, altered bile acid homeostasis, and immune response as mechanisms of TAK-875 DILI and the contribution of genetic risk factors in oxidative response and mitochondrial pathways to the toxicity susceptibility observed in patients. We tested the hypothesis that a novel preclinical approach based on gene pathway analysis in the livers of Collaborative Cross mice could be used to identify human-relevant mechanisms of toxicity and genetic risk factors at the level of the hepatocyte as reported in a human genome-wide association study.

Inter-annual variation of mercury in aquatic bird eggs and fish from a large subarctic lake under a warming climate.

Understanding changes in environmental mercury concentrations is important for assessing the risk to human and wildlife populations from this potent toxicant. Here, we use herring gull (Larus argentatus) eggs to evaluate temporal changes in total mercury (THg) availability from two locations on Great Slave Lake (GSL), Northwest Territories, Canada. Egg THg concentrations increased through time, but this change was due to shifts in gull diets.

Trispecific antibodies enhance the therapeutic efficacy of tumor-directed T cells through T cell receptor co-stimulation.

Despite the significant therapeutic advances provided by immune-checkpoint blockade and chimeric antigen receptor T cell treatments, many malignancies remain unresponsive to immunotherapy. Bispecific antibodies targeting tumor antigens and activating T cell receptor signaling have shown some clinical efficacy; however, providing co-stimulatory signals may improve T cell responses against tumors. Here, we developed a trispecific antibody that interacts with CD38, CD3 and CD28 to enhance both T cell activation and tumor targeting.

Fasiglifam (TAK-875) Alters Bile Acid Homeostasis in Rats and Dogs: A Potential Cause of Drug Induced Liver Injury.

Fasiglifam (TAK-875), a Free Fatty Acid Receptor 1 (FFAR1) agonist in development for the treatment of type 2 diabetes, was voluntarily terminated in phase 3 due to adverse liver effects. A mechanistic investigation described in this manuscript focused on the inhibition of bile acid (BA) transporters as a driver of the liver findings. TAK-875 was an in vitro inhibitor of multiple influx (NTCP and OATPs) and efflux (BSEP and MRPs) hepatobiliary BA transporters at micromolar concentrations.

The Rat microRNA body atlas; Evaluation of the microRNA content of rat organs through deep sequencing and characterization of pancreas enriched miRNAs as biomarkers of pancreatic toxicity in the rat and dog.

Background: MicroRNAs (miRNA) are ~19-25 nucleotide long RNA molecules that fine tune gene expression through the inhibition of translation or degradation of the mRNA through incorporation into the RNA induced silencing complex (RISC). MicroRNAs are stable in the serum and plasma, are detectable in a wide variety of body fluids, are conserved across veterinary species and humans and are expressed in a tissue specific manner. They can be detected at low concentrations in circulation in animals and humans, generating interest in the utilization of miRNAs as serum and/or plasma based biomarkers of tissue injury.

The beagle dog MicroRNA tissue atlas: identifying translatable biomarkers of organ toxicity.

Background: MicroRNAs (miRNA) are varied in length, under 25 nucleotides, single-stranded noncoding RNA that regulate post-transcriptional gene expression via translational repression or mRNA degradation. Elevated levels of miRNAs can be detected in systemic circulation after tissue injury, suggesting that miRNAs are released following cellular damage. Because of their remarkable stability, ease of detection in biofluids, and tissue specific expression patterns, miRNAs have the potential to be specific biomarkers of organ injury.

Identification of microRNA biomarker candidates in urine and plasma from rats with kidney or liver damage.

MicroRNAs (miRNA) are short single-stranded RNA sequences that have a role in the post-transcriptional regulation of genes. The identification of tissue specific or enriched miRNAs has great potential as novel safety biomarkers. One longstanding goal is to associate the increase of miRNA in biofluids (e.

Mathematical model for shear stress dependent NO and adenine nucleotide production from endothelial cells.

We developed a mass transport model for a parallel-plate flow chamber apparatus to predict the concentrations of nitric oxide (NO) and adenine nucleotides (ATP, ADP) produced by cultured endothelial cells (ECs) and investigated how the net rates of production, degradation, and mass transport for these three chemical species vary with changes in wall shear stress (τw). These simulations provide an improved understanding of experimental results obtained with parallel-plate flow chambers and allows quantitative analysis of the relationship between τw, adenine nucleotide concentrations, and NO produced by ECs. Experimental data obtained after altering ATP and ADP concentrations with apyrase were analyzed to quantify changes in the rate of NO production (RNO).

Severe airway epithelial injury, aberrant repair and bronchiolitis obliterans develops after diacetyl instillation in rats.

Background: Bronchiolitis obliterans (BO) is a fibrotic lung disease that occurs in a variety of clinical settings, including toxin exposures, autoimmunity and lung or bone marrow transplant. Despite its increasing clinical importance, little is known regarding the underlying disease mechanisms due to a lack of adequate small animal BO models. Recent epidemiological studies have implicated exposure to diacetyl (DA), a volatile component of artificial butter flavoring, as a cause of BO in otherwise healthy factory workers.

3D network model of NO transport in tissue.

We developed a mathematical model to simulate shear stress-dependent nitric oxide (NO) production and transport in a 3D microcirculatory network based on published data. The model consists of a 100 μm × 500 μm × 75 μm rectangular volume of tissue containing two arteriole-branching trees, and nine capillaries surrounding the vessels. Computed distributions for NO in blood, vascular walls, and surrounding tissue were affected by hematocrit (Hct) and wall shear stress (WSS) in the network.

Direct, real-time measurement of shear stress-induced nitric oxide produced from endothelial cells in vitro.

Nitric oxide (NO) produced by the endothelium is involved in the regulation of vascular tone. Decreased NO production or availability has been linked to endothelial dysfunction in hypercholesterolemia and hypertension. Shear stress-induced NO release is a well-established phenomenon, yet the cellular mechanisms of this response are not completely understood.

Pleural effects of indium phosphide in B6C3F1 mice: nonfibrous particulate induced pleural fibrosis.

The mechanism(s) by which chronic inhalation of indium phosphide (InP) particles causes pleural fibrosis is not known. Few studies of InP pleural toxicity have been conducted because of the challenges in conducting particulate inhalation exposures, and because the pleural lesions developed slowly over the 2-year inhalation study. The authors investigated whether InP (1 mg/kg) administered by a single oropharyngeal aspiration would cause pleural fibrosis in male B6C3F1 mice.

Respiratory toxicity of diacetyl in C57BL/6 mice.

Diacetyl, a component of artificial butter flavoring, is a potential etiological agent of obliterative bronchiolitis (OB); however, the toxic dose and mechanisms of toxicity remain controversial. We evaluated the respiratory toxicity of diacetyl in a murine model using several exposure profiles relevant to workplace conditions at microwave popcorn packaging plants. Male C57Bl/6 mice were exposed to inhaled diacetyl across several concentrations and duration profiles, or by direct oropharyngeal aspiration.

Core-SINE blocks comprise a large fraction of monotreme genomes; implications for vertebrate chromosome evolution.

The genomes of the egg-laying platypus and echidna are of particular interest because monotremes are the most basal mammal group. The chromosomal distribution of an ancient family of short interspersed repeats (SINEs), the core-SINEs, was investigated to better understand monotreme genome organization and evolution. Previous studies have identified the core-SINE as the predominant SINE in the platypus genome, and in this study we quantified, characterized and localized subfamilies.

A diversity of serine phage integrases mediate site-specific recombination in mammalian cells.

This study evaluated the ability of five serine phage integrases, from phages A118, U153, Bxb1, phiFC1, and phiRV1, to mediate recombination in mammalian cells. Two types of recombination were investigated, including the ability of an integrase to mediate recombination between its own phage att sites in the context of a mammalian cell and the ability of an integrase to perform genomic integration pairing a phage att site with an endogenous mammalian sequence. We demonstrated that the A118 integrase mediated precise intra-molecular recombination of a plasmid containing its attB and attP sites at a frequency of approximately 50% in human cells.

Integration specificity of phage phiC31 integrase in the human genome.

The site-specific integrase from bacteriophage phiC31 functions in mammalian cells and is being applied for genetic engineering, including gene therapy. The phiC31 integrase catalyzes precise, unidirectional recombination between its 30-40-bp attP and attB recognition sites. In mammalian cells, the enzyme also mediates integration of plasmids bearing attB into native sequences that have partial sequence identity with attP, termed pseudo attP sites.

Autosomal location of genes from the conserved mammalian X in the platypus (Ornithorhynchus anatinus): implications for mammalian sex chromosome evolution.

Mammalian sex chromosomes evolved from an ancient autosomal pair. Mapping of human X- and Y-borne genes in distantly related mammals and non-mammalian vertebrates has proved valuable to help deduce the evolution of this unique part of the genome. The platypus, a monotreme mammal distantly related to eutherians and marsupials, has an extraordinary sex chromosome system comprising five X and five Y chromosomes that form a translocation chain at male meiosis.

Complex events in the evolution of the human pseudoautosomal region 2 (PAR2).

The 320-kb human pseudoautosomal region 2 (PAR2) at the tips of the long arms of the X and Y chromosomes is thought to have been duplicated onto the Y chromosome recently in primate evolution. The four genes within PAR2 have been proposed to constitute two zones with different base ratios and transcription, one of which was added recently to the X chromosome. To test this hypothesis, we cloned and mapped PAR2 genes in other species, the lemur, the cat, and a marsupial, the tammar wallaby.