Direct and cytokine-mediated effects of albumin-fused growth hormone, TV-1106, on CYP enzyme expression in human hepatocytes in vitro

Some biologics can modulate cytokines that may lead to changes in expression of drugmetabolizing enzymes and cause drug-drug interactions (DDI). DDI potential of TV- 1106—an albumin-fused growth hormone (GH)—was investigated. In this study, human blood was exposed to recombinant human growth hormone (rhGH) or TV-1106, followed by isolation of the plasma and its application to human hepatocytes. While the treatment of blood with rhGH increased multiple cytokines, treatment of blood with TV-1106 had no effect on any of the nine cytokines tested. The interleukin (IL)-6 concentration was higher in the rhGH then in the TV-1106-treated plasma (P < .05). While rhGH had little or no effect on CYP1A2 or CYP2C19 mRNA but increased CYP3A4 mRNA twofold, TV-1106 had little or no effect on cytochrome P450 (CYP) mRNAs in hepatocytes. Although the plasma from rhGH-treated blood lowered CYP1A2 activity, the TV-1106 plasma had no effect on CYP activities. The CYP1A2 activity was lower in the rhGH- then in the TV-1106-plasma treated hepatocytes (P < .05). The results indicated that fusing GH with albumin made TV-1106 an unlikely participant of CYP1A2, CYP2C19 or CYP3A4-facilitated, direct or cytokine-driven DDI.The authors would like to thank scientists in the Scientific Operations at Sekisui XenoTech for their technical assistance

Expression of Ligands to NKp46 in Benign and Malignant Melanocytes

Human melanoma cell lines were shown to express ligands for the natural cytotoxicity receptor, NKp46, expressed by natural killer (NK) cells. We aimed to examine the expression of ligands for NKp46 by various primary human melanocytic cells and melanocytic lesions. Sections from primary nevi and melanomas were tested for expression of NKp46 ligands employing chimeric NKp46-Fc for staining. The melanocytes present in the reticular dermis were negative for NKp46 ligands in common nevi; in malignant melanocytic lesions, the deeper melanocytes were focally positive. In dermoepidermal junction of all melanocytic lesions, the melanocytes showed enhanced expression of NKp46 ligands. Melanophages in all lesions were consistently positive for NKp46 ligands. These observations establish the expression of NKp46 ligands by primary-transformed melanocytes. Normal melanocytes did not express ligands to NKp46. Therefore, the results show (i) a correlation between the malignant potential of the lesion and the expression of NKp46 ligands in the reticular dermis, and (ii) enhanced expression of NKp46 ligands in the active proliferation zone (dermoepidermal junction) of nevi and melanomas. Ligands to NKp46 were expressed on the membrane and within the cells. The physiological role of NKp46 ligands in the progression of malignancy within melanocytic lesions should be explored further

Characterization of Graphene-Nanoplatelets Structure via Thermogravimetry

The rapid increase in graphene-based applications has been accompanied by novel top-down manufacturing methods for graphene and its derivatives (e.g., graphene nanoplatelets (GnPs)). The characterization of the <i>bulk</i> properties of these materials by imaging and surface techniques (e.g., electron microscopy and Raman spectroscopy) is only possible through laborious and time-consuming statistical analysis, which precludes simple and efficient quality control during GnP production. We report that thermogravimetry (TG) may be utilized, beyond its conventional applications (e.g., quantification of impurities or surfactants, or labile functional groups) to characterize <i>bulk</i> GnP properties. We characterize the structural parameters of GnP (i.e., defect density, mean lateral dimension, and polydispersity) by imaging and surface techniques, on one hand, and by a systematic TG, on the other. The combined data demonstrate that the combustion temperature of commercially available and laboratory-prepared GnPs is correlated with their mean lateral dimension and defect density, while the combustion temperature range is proportional to their polydispersity index. Mapping all these parameters allows one to evaluate the GnPs’ structure following a simple thermogravimetric experiment (without necessitating further statistical analysis). Finally, TG is also used to detect and quantify different GnP constituents in powder and to conduct rapid quality-control tests during GnP production

Carbon Allotropes Accelerate Hydrogenation via Spillover Mechanism

Solid-phase hydrogenation kinetics can be substantially increased by utilizing hydrogen spillover phenomenon. Carbonaceous allotropes are considered as promising spillover agents (SOAs) for improved hydrogen transport rate. We studied the effect of carbon-based SOA properties on irreversible hydrogenation. We divided the reaction into two major stages, near- and far-field hydrogenation (with respect to a catalyst), and determined their rate-limiting steps. The hydrogenation kinetics was analyzed for hydrogen originating from either catalyst on activated carbon or catalyst-decorated carbon nanotubes. The far-field hydrogenation is investigated for three types of loaded nanocarbons: 1D (nanotubes), 2D (graphene), and 3D (activated carbon). We found that the kinetics acceleration is strongly correlated with the nanocarbon dimension, 1D > 2D > 3D, and could reach almost 2 orders of magnitude. These findings are useful for the study of reversible hydrogen storage applications

Dengue Virus Replicon Expressing the Nonstructural Proteins Suffices To Enhance Membrane Expression of HLA Class I and Inhibit Lysis by Human NK Cells▿

Many viruses escape the cellular immune response by downregulating cell surface expression of major histocompatibility complex (MHC) class I molecules. However, infection of cells with flaviviruses can upregulate the expression of these molecules. In this study we analyzed the expression of MHC class I in K562 and THP-1 human cell lines that were stably transfected with self-replicating subgenomic dengue virus RNA (replicons) and express all the dengue virus nonstructural proteins together. We show that MHC class I expression is upregulated in the dengue virus replicon-expressing cells and that the binding of natural killer (NK) inhibitory receptors to these cells is augmented. This upregulation results in reduced susceptibility of the dengue virus replicon-expressing cells to NK lysis, indicating a possible mechanism for evasion of the dengue virus from NK cell recognition. Visualizing MHC class I expression in replicon-containing K562 and THP-1 cells by confocal microscopy demonstrated aggregation of MHC class I molecules on the cell surface. Finally, replicon-expressing K562 cells manifested increased TAP (transporter associated with antigen processing) and LMP (low-molecular-mass protein) gene transcription, while replicon-expressing THP-1 cells manifested increased NF-κB activity and MHC class I transcription. We suggest that expression of dengue virus nonstructural proteins is sufficient to induce MHC class I upregulation through both TAP-dependent and -independent mechanisms. Additionally, aggregation of MHC class I molecules on the cell membrane also contributes to significantly higher binding of low-affinity NK inhibitory receptors, resulting in lower sensitivity to lysis by NK cells

Minimally invasive micro sclerostomy (MIMS) procedure in the treatment of open-angle glaucoma

Abstract Background To evaluate the safety and efficacy of the Minimally Invasive Micro Sclerotomy (MIMS) procedure in the management of uncontrolled open-angle glaucoma. Methods A prospective, open-label, single-arm clinical evaluation with intra-subject comparisons performed at the Ophthalmologic Center after S.V. Malayan, Yerevan, Armenia. Included were adults with primary open-angle glaucoma (OAG) (N = 114) or exfoliative glaucoma (N = 6) who were uncontrolled (IOP > 21) on tolerated topical medication. Mild (N = 7), moderate (N = 66) and severe (n = 47) cases were prospectively included without preselection. Following subconjunctival Mitomycin C, an ab-interno MIMS procedure was performed alone (N = 100) or combined with phacoemulsification (N = 20). Patients were followed for 52 weeks. Procedure-related complications and adverse events were recorded. Success criteria were defined as -5  21 mmHg on tolerated medication. At 52 weeks (n = 93), mean IOP decreased by 38% from baseline (P < 0.001), from 27.9 ± 3.7 to 17.5 ± 5.3 mmHg, a difference of 10.5 mmHg (95% CI: -11.7, -9.3). One-year qualified success was documented in 82.1% (95% CI: 72.9%,89.2%) of the patients and complete success, in 70.5% (60.3-79.4%). 60% (95 CI:49.4%,69.9%) of the patients achieved maximum IOP level of 14 mmHg or at least 30% reduction in IOP. Conclusions MIMS procedure is a relatively simple, short and safe minimally invasive bleb-forming procedure. Its efficacy, as found in this short-term evaluation, lends it suitable for mild and moderate uncontrolled open-angle glaucoma patients. Trial registration ClinicalTrials.gov ID: NCT04503590 2019-05-29