7196 research outputs found
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Metabolic and immunomodulatory control of type 1 diabetes via orally delivered bile-acid-polymer nanocarriers of insulin or rapamycin
No full textWe describe oral nanocarriers, termed “NanoPills” (NPs), for simultaneous short-term control and long-term reversal of pancreatic inflammation. We hypothesized that since bile acids emulsify fats during digestion, regulate glucose and modulate immunity, that NPs constructed from polymeric bile acid will be effective, multifunctional, oral therapeutics. Polymerized ursodeoxycholic acid (pUDCA) NP protected encapsulated agent in the stomach, permeated intestinal epithelia, then bound macrophage bile receptors with high avidity. Strikingly, pUDCA NPs localized to the pancreas after oral ingestion through macrophage-mediated transport and particle enterohepatic circulation. In a drug-induced pancreatic inflammation model, rapamycin-loaded NPs prevented disease. In a spontaneous model of type I diabetes (T1D), NP alone restored normoglycemia for 2 weeks and reversed disease with loaded insulin. Thus, for the first time, an integrative approach is presented enabling oral delivery through a carrier that intrinsically restores endogenous pancreatic insulin secretion, and tolerogenic immunity for rapid control and long-term regulation of T1D
EBI2 is expressed in glial cells in multiple sclerosis lesions and its knock-out modulates remyelination in the cuprizone model
No full textEBI2 receptor regulates the immune system and in multiple sclerosis is upregulated in the central nervous system infiltrating lymphocytes. In newborn EBI2-deficient mice, myelin development is delayed and its persistent antagonism inhibits remyelination in chemically-demyelinated organotypic cerebellar slices. We used the cuprizone model of multiple sclerosis to elucidate the role of central nervous system-expressed EBI2 in de- and remyelination. The wild-type and EBI2 knock-out mice were fed 0.2% cuprizone in chow for five weeks and allowed to recover on a normal diet for two weeks. The data showed less efficient recovery of myelin, attenuated oligodendrocyte loss, fewer astrocytes and increased total cholesterol levels in the EBI2 knock-out mice after recovery. Moreover, the wild-type mice upregulated EBI2 expression after recovery confirming the involvement of EBI2 signalling during recovery from demyelination in the cuprizone model. The pro-inflammatory cytokine levels were at comparable levels in the wild-type and EBI2 knock-out mice, with only minor differences in TNFα and IL1β levels either at peak or during recovery. The neuroinflammatory signalling molecules, Abl1 kinase and NFКB1 (p105/p50) subunit, were significantly downregulated in the EBI2 knock-out mice at peak of disease. Immunohistochemical investigations of EBI2 receptor distribution in the CNS cells in MS brain revealed strong expression of EBI2 in astrocytes and microglia inside the plaques implicating glia-expressed EBI2 in multiple sclerosis pathophysiology. Taken together, these findings demonstrate the involvement of EBI2 signalling in the recovery from demyelination rather than in demyelination and as such warrant further research into the role of EBI2 in remyelination
Combinations with allosteric SHP2 inhibitor TNO155 to block receptor tyrosine kinase signaling
No full textPurpose: SHP2 inhibitors offer an appealing and novel approach to inhibit receptor tyrosine kinase (RTK) signaling, which is the oncogenic driver in many tumors or is frequently feedback activated in response to targeted therapies including RTK inhibitors and MAPK inhibitors. We seek to evaluate the efficacy and synergistic mechanisms of combinations with a novel SHP2 inhibitor, TNO155, to inform their clinical development. Experimental Design: The combinations of TNO155 with EGFR inhibitors (EGFRi), BRAFi, KRASG12Ci, CDK4/6i, and anti–programmed cell death-1 (PD-1) antibody were tested in appropriate cancer models in vitro and in vivo, and their effects on downstream signaling were examined. Results: In EGFR-mutant lung cancer models, combination benefit of TNO155 and the EGFRi nazartinib was observed, coincident with sustained ERK inhibition. In BRAFV600E colorectal cancer models, TNO155 synergized with BRAF plus MEK inhibitors by blocking ERK feedback activation by different RTKs. In KRASG12C cancer cells, TNO155 effectively blocked the feedback activation of wild-type KRAS or other RAS isoforms induced by KRASG12Ci and greatly enhanced efficacy. In addition, TNO155 and the CDK4/6 inhibitor ribociclib showed combination benefit in a large panel of lung and colorectal cancer patient–derived xenografts, including those with KRAS mutations. Finally, TNO155 effectively inhibited RAS activation by colony-stimulating factor 1 receptor, which is critical for the maturation of immunosuppressive tumor-associated macrophages, and showed combination activity with anti–PD-1 antibody. Conclusions: Our findings suggest TNO155 is an effective agent for blocking both tumor-promoting and immune-suppressive RTK signaling in RTK- and MAPK-driven cancers and their tumor microenvironment. Our data provide the rationale for evaluating these combinations clinically
How can single particle compression and nanoindentation contribute to the understanding of pharmaceutical powder compression?
No full textThe deformation behaviour of a powder is a crucial parameter in powder compaction and affects powder compressibility as well as compactibility. The classical approach for the characterization of the deformation behaviour is the performance of powder bulk compression experiments combined with the application of mathematical models, such as the model of Heckel, for the derivation of characteristic compression parameters. However, these models are typically empirical and the correlation of the derived parameters with the deformation behaviour is not fully physically proved. Single particle compression enables the in-depth investigation of the deformation behaviour of particulate materials. However, interpretation is usually limited to ideal shapes due to the easier accessibility of sizes for analysis based on geometric dimensions, such as the contact area between the compression tool and the particle.
In this study, single particle compression experiments were performed for the characterization of the deformation behaviour of common pharmaceutical excipients and active pharmaceutical ingredients with various, non-ideal particle morphologies and the findings are compared with the results from powder compression. It is found, that single particle compression is a useful tool for the qualitative characterization of the deformation behaviour and is useful for the improvement of the process understanding of powder compaction. However, the derivation of quantitative values and their transferability to powder compression is very limited
Research Relevant Conditions and Pathology in Nonhuman Primates
No full textBiomedical research involving animal models continues to provide important insights into disease pathogenesis and treatment of diseases that impact human health. In particular, nonhuman primates (NHPs) have been used extensively in translational research due to their phylogenetic proximity to humans and similarities to disease pathogenesis and treatment responses as assessed in clinical trials. Microscopic changes in tissues remain a significant endpoint in studies involving these models. Spontaneous, expected (ie, incidental or background) histopathologic changes are commonly encountered and influenced by species, genetic variations, age, and geographical origin of animals, including exposure to infectious or parasitic agents. Often, the background findings confound study-related changes, because numbers of NHPs used in research are limited by animal welfare and other considerations. Moreover, background findings in NHPs can be exacerbated by experimental conditions such as treatment with xenobiotics (eg, infectious morphological changes related to immunosuppressive therapy). This review and summary of research-relevant conditions and pathology in rhesus and cynomolgus macaques, baboons, African green monkeys, common marmosets, tamarins, and squirrel and owl monkeys aims to improve the interpretation and validity of NHP studies
OBF1 and Oct factors control the germinal center transcriptional program
No full textOBF1 is a specific coactivator of the POU family transcription factors OCT1 and OCT2. OBF1 and OCT2 are B cell–specific and indispensable for germinal center (GC) formation, but their mechanism of action is unclear. Here, we show by chromatin immunoprecipitation-sequencing that OBF1 extensively colocalizes with OCT1 and OCT2. We found that these factors also often colocalize with transcription factors of the ETS family. Furthermore, we showed that OBF1, OCT2, and OCT1 bind widely to the promoters or enhancers of genes involved in GC formation in mouse and human GC B cells. Short hairpin RNA knockdown experiments demonstrated that OCT1, OCT2, and OBF1 regulate each other and are essential for proliferation of GC-derived lymphoma cell lines. OBF1 downregulation disrupts the GC transcriptional program: genes involved in GC maintenance, such as BCL6, are downregulated, whereas genes related to exit from the GC program, such as IRF4, are upregulated. Ectopic expression of BCL6 does not restore the proliferation of GC-derived lymphoma cells depleted of OBF1 unless IRF4 is also depleted, indicating that OBF1 controls an essential regulatory node in GC differentiation
R&D efficiency of leading pharmaceutical companies — a 20-year analysis
No full textWe investigated financial data, 270 NMEs and over 160,000 bibliographic data of 14 leading pharmaceutical companies (1999 to 2018).
Our analysis suggests that the most important sources for NMEs in past 20 years were proprietary research (40%), M&A activities (41%) and drug licensing (19%), indicating the high relevance of external innovation in the industry.
We found a nearly linear correlation between R&D spending and R&D output, i.e. the more a company invested in R&D in the past 20 years the higher the output both in terms of NMEs and cumulative impact factors.
Our investigations indicate economies of scale in R&D: Pharmaceutical companies needed on average 16,315 employees in R&D to generate 25 NMEs over the past 20 years. The model the describes the R&D input/output-relation indicates that a further increase in R&D output by 5 NMEs (from 25 to 30 NMEs) would require an additional 3,039 R&D employees, and that the next 5 NMEs would need an extra of 2,570 additional R&D staff
Genome-wide CRISPR screen identifies protein pathways modulating tau protein levels in neurons
No full textAggregates of hyperphosphorylated tau protein are a pathological hallmark of more than 20 distinct neurodegenerative diseases, including Alzheimer's disease, progressive supranuclear palsy, and frontotemporal dementia. While the exact mechanism of tau aggregation is unknown, the accumulation of aggregates correlates with disease progression. Here we report a genome-wide CRISPR screen to identify modulators of endogenous tau protein for the first time. Primary screens performed in SH-SY5Y cells, identified positive and negative regulators of tau protein levels. Hit validation of the top 43 candidate genes was performed using Ngn2-induced human cortical excitatory neurons. Using this approach, genes and pathways involved in modulation of endogenous tau levels were identified, including chromatin modifying enzymes, neddylation and ubiquitin pathway members, and components of the mTOR pathway. TSC1, a critical component of the mTOR pathway, was further validated in vivo, demonstrating the relevance of this screening strategy. These findings may have implications for treating neurodegenerative diseases in the future
Single-cell and bulk transcriptomics of the liver reveals potential targets of NASH with fibrosis
No full textFibrosis is characterized by the excessive production of collagen and other extracellular matrix (ECM) components and represents a leading cause of morbidity and mortality worldwide. Previous studies of nonalcoholic steatohepatitis (NASH) with fibrosis were largely restricted to bulk transcriptome profiles. Thus, our understanding of this disease is limited by an incomplete characterization of liver cell types in general and hepatic stellate cells (HSCs) in particular, given that activated HSCs are the major fibrogenic population during liver fibrosis development. To help fill this gap, we profiled 17,810 non-parenchymal cells derived from six healthy human liver tissues. In conjunction with public single-cell data of fibrotic/cirrhotic human liver, it enables the assessment and identification of potential intercellular communications (e.g., ITGAV–LAMC1, TNFRSF11B–VWF and NOTCH2–DLL4 signaling axes) and regulons (e.g., RUNX1 and CREB3L1) responsible for the activation of HSCs during fibrogenesis. Bulk RNA-seq data of NASH patient livers and rodent models for liver fibrosis of diverse etiologies allowed us to evaluate the translatability of candidate therapeutic targets for NASH with fibrosis. We identified 61 liver fibrosis-associated genes (e.g., AEBP1, PRRX1 and LARP6) that may serve as a repertoire of translatable drug target candidates. Consistent with the above regulon results, gene regulatory network analysis allowed the identification of CREB3L1 as a master regulator of many of the 61 genes. Together, this study sheds light on potential cell-cell interactions and regulons that underlie HSC activation and reveals genes that may represent prospective hallmark signatures for liver fibrosis