Production of a SARS-CoV-2 Spike Protein Vaccine Using the Baculovirus Expression Vector System

Various COVID-19 vaccines are currently in development, as the COVID-19 pandemic has created an unmet need for protection against the SARS-CoV-2 virus. While there are many different types of vaccines, we focused on developing one that would be safe, affordable, and quickly available for emergency use. A vaccine synthesized using recombinant proteins utilizes a reliable and well-studied technological platform, avoids the safety risks inherent to viral vectors, and provides a cost-effective, scalable method of production of antigen used to induce an immune response. Other vaccines on the market notably include Pfizer’s and Moderna’s mRNA based vaccines. Although these are widely used, there is still a large demand for an inexpensive yet safe and effective vaccine. Herein, we propose the production of 500 million doses of a recombinant spike protein-based COVID-19 vaccine in a quick time frame and cost-effective manner, using the baculovirus expression vector system (BEVS). Our upstream process involves a three-stage cellular scale-up from shake flasks to WAVE bioreactors to perfusion to production bioreactors, as well as an additional two-stage viral amplification from flasks to WAVE bioreactors. Our downstream process involves a six-stage protein recovery with depth filtration, his-tag chromatography, viral inactivation, ion-exchange chromatography, viral filtration, and diafiltration. We will be partnering with a contract manufacturing organization (CMO) for this project, as we do not have the time to quickly build a plant to get these vaccines out for emergency use. This arrangement makes this process highly profitable. Selling each dose for $16 yields net earnings near$2 billion and an extremely high IRR due to the lack of permanent and fixed costs other than our rental fee. The IRR for the CMO is estimated to be at least 16% with the NPV of the plant at $855,000 and an ROI of 18%

Investigation of Disorder in Ho2Ti2-xZrxO7: Pyrochlore to Defective Fluorite Chemical Series

International audiencePyrochlore oxides (A2B2O7) – and other fluorite-derived complex oxides – are interesting for not only their wide variety of desirable properties, such as ionic conduction and radiation tolerance, but also for their complex defect formation and disordering mechanisms that often give rise to their properties. We have used neutron total scattering to study in detail all structural aspects of the disordering of pyrochlore which involves randomization of both cation and anion sublattices. By means of diffraction and pair distribution function analysis of a Ho2Ti2-xZrxO7 (x = 0.0-2.0) solid solution series, the disordering mechanism was studied simultaneously over multiple material length scales with novel insight into the local atomic arrangements. With increasing Zr-content, the series exhibits an order-disorder transformation from pyrochlore (space group: Fd-3m) to defective fluorite (space group: Fm-3m) across a narrow compositional range (x = 1.0-1.5) over the long length-scale, while the local atomic arrangement changes gradually to a weberite-type structure (space group: C2221) over the whole compositional range. This distinct disordering scheme can be explained by the movement of a 48f oxygen to a vacant 8a site, creating 7-coordinated Zr4+ sites that produce local weberite-type building blocks. These building blocks accumulate until a critical Zr-content (x ~ 1.2) is reached which triggers the rearrangement of weberite-type units into long-range structural defective fluorite

Multicolor FISH using tándem probes to detect Chromosome alterations in humans cells and populations exposed to genotoxic agents

12 páginas, 2 figuras y 2 tablas estadísticasFluorescence in situ hybridization (FISH) with chromosome- or region-specific DNA probes is being increasingly used in cytogenetic studies to detect aneuploidy in interphase human cells. This technique utilizes chemically modified DNA sequences (probes) which hybridize to distinct regions, often blocks of repetitive DNA, located on specific chromosomes. Hybridization with these probes in situ results in the staining of a compact chromosomal región which can be easily detected on metaphase chromosomes or within interphase nuclei. The number of chromosomes within a given cell is then determined by counting the number of hybridized regions. Where conventional cytogenetics is limited to actively proliferating cells or those which could be stimulated to divide in vitro such as peripheral blood lymphocytes, FISH studies with centromeric probes can be conducted on interphase cells, significantly increasing the types of cells and tissues available for analysis.Peer reviewe

Non-invasive treatment with near-infrared light: A novel mechanisms-based strategy that evokes sustained reduction in brain injury after stroke

Ischemic stroke is a debilitating disease that causes significant brain injury. While restoration of blood flow is critical to salvage the ischemic brain, reperfusion can exacerbate damage by inducing generation of reactive oxygen species (ROS). Recent studies by our group found that non-invasive mitochondrial modulation with near-infrared (NIR) light limits ROS generation following global brain ischemia. NIR interacts with cytochrome c oxidase (COX) to transiently reduce COX activity, attenuate mitochondrial membrane potential hyperpolarization, and thus reduce ROS production. We evaluated a specific combination of COX-inhibitory NIR (750 nm and 950 nm) in a rat stroke model with longitudinal analysis of brain injury using magnetic resonance imaging. Treatment with NIR for 2 h resulted in a 21% reduction in brain injury at 24 h of reperfusion measured by diffusion-weighted imaging (DWI) and a 25% reduction in infarct volume measured by T2-weighted imaging (T2WI) at 7 and 14 days of reperfusion, respectively. Additionally, extended treatment reduced brain injury in the acute phase of brain injury, and 7 and 14 days of reperfusion, demonstrating a \u3e50% reduction in infarction. Our data suggest that mitochondrial modulation with NIR attenuates ischemia-reperfusion injury and evokes a sustained reduction in infarct volume following ischemic stroke

Placental plasticity in monochorionic twins: Impact on birth weight and placental weight

INTRODUCTION The knowledge about adaptive mechanisms of monochorionic placentas to fulfill the demands of two instead of one fetus is largely speculative. The aim of our study was to investigate the impact of chorionicity on birth weight and placental weight in twin pregnancies. METHODS Forty Monochorionic (MC) and 43 dichorionic (DC) twin pregnancies were included in this retrospective study. Individual and total (sum of both twins) birth weights, placental weights ratios between placental and birth weights and observed-to-expected (O/E)-ratios were calculated and analyzed. Additionally, we investigated whether in twin pregnancies placental and birth weights follow the law of allometric metabolic scaling. RESULTS MC pregnancies showed higher placental O/E-ratios than DC ones (2.25 ± 0.85 versus 1.66 ± 0.61; p < 0.05), whereas the total neonatal birth weight O/E-ratios were not different. In DC twins total placental weights correlated significantly with gestational age (r = 0.74, p < 0.001), but not in MC twins. Analysis of deliveries ≤32 weeks revealed that the placenta to birth weight ratio in MC twins was higher than in matched DC twins (0.49 ± 0.3 versus 0.24 ± 0.03; p = 0.03). Allometric metabolic scaling revealed that dichorionic twin placentas scale with birth weight, while the monochorionic ones do not. DISCUSSION The weight of MC placentas compared to that of DC is not gestational age dependent in the third trimester. Therefore an early accelerated placental growth pattern has to be postulated which leads to an excess placental mass particularly below 32 weeks of gestation. The monochorionic twins do not follow allometric metabolic scaling principle making them more vulnerable to placental compromise

Systematic study of short- and long-range correlations in RE3TaO7 weberite-type compounds by neutron total scattering and X-ray diffraction

International audienceThe atomic structures of the lanthanide tantalates, Ln3TaO7, series (Ln = Pr, Tb, Dy, Ho, Tm, Yb) were systematically investigated using total scattering techniques. High-energy X-ray and neutron diffraction analysis revealed that the long-range structures can be grouped into three distinct families: (1) ordered Cmcm (Ln = Pr), (2) ordered Ccmm (Ln = Tb, Dy, Ho), and (3) disordered, defect-fluorite Fm[3 with combining macron]m (Ln = Ho, Tm, Yb). These findings help to clarify the symmetry discrepancy for the already reported long-range structures in the literature. The short-range analysis of neutron total scattering data via pair distribution functions reveals a high degree of structural heterogeneity across length scales for all compounds, with distinct local atomic arrangements that are not fully captured by the average, long-range structure. The short-range structures at the level of coordination polyhedra are better captured by a set of alternative non-centrosymmetric structural models: (1) C2cm, (2) C2221, and (3) C2mm. This establishes a short-range multiferroic character for weberite-type tantalates because ferroelectric interactions compete with magnetic correlations. These ferroelectric interactions are particularly pronounced for the disordered compounds Tm3TaO7 and Yb3TaO7. The structural differences among the three families are the result of changes in TaO6 polyhedral tilt (transition between families 1 and 2) and dipolar interactions of off-centered Ta cations (transition between families 2 and 3)