Optimization and Validation of a Liquid Formulation for a New Recombinant Veterinary Product using QbD Approach

Protein formulation and drug characterization are one of the most difficult and time-consuming tasks because of the complexity of biotherapeutic proteins. Hence, maintaining a protein drug in its active state typically requires preventing changes in its physical and chemical properties. Quality by Design (QbD) is a systematic approach emphasizing product and process understanding. Design of Experiments (DoE) is one of the most important QbD tools, allowing the possibility to modify the formulation attributes within a defined design space. Here, we report the validation of a RP-HPLC assay for recombinant equine chorionic gonadotropin (reCG) that demonstrated a high correlation with the in vivo potency biological assay. QbD concepts were then applied to obtain an optimized liquid formulation of reCG with a predefined quality product profile. The developed strategy demonstrates the importance of applying multivariable strategies as DoE to simplify formulation stages, improving the quality of the obtained results. Moreover, it is important to highlight that this is the first time that a liquid formulation is reported for an eCG molecule, since, up to now, the only eCG products available in the market for veterinary use consisted in partially purified preparations of pregnant mare serum gonadotropin (PMSG) presented as a lyophilized product.

Design and characterization of chimeric Rabies-SARS-CoV-2 virus-like particles for vaccine purposes

Due to the high number of doses required to achieve adequate coverage in the context of COVID-19 pandemics, there is a great need for novel vaccine developments. In this field, there have been research approaches that focused on the production of SARS-CoV-2 virus-like particles. These are promising vaccine candidates as their structure is similar to that of native virions but they lack the genome, constituting a biosafe alternative. In order to produce these structures using mammal cells, it has been established that all four structural proteins must be expressed. Here we report the generation and characterization of a novel chimeric virus-like particle (VLP) that can be produced by the expression of a single novel fusion protein that contains SARS-CoV-2 spike (S) ectodomain fused to rabies glycoprotein membrane anchoring region in HEK293 cells. This protein is structurally similar to native S and can autonomously bud forming enveloped VLPs that resemble native virions both in size and in morphology, displaying S ectodomain and receptor binding domain (RBD) on their surface. As a proof of concept, we analyzed the immunogenicity of this vaccine candidate in mice and confirmed the generation of anti-S, anti-RBD, and neutralizing antibodies. KEY POINTS: • A novel fusion rabies glycoprotein containing S ectodomain was designed. • Fusion protein formed cVLPs that were morphologically similar to SARS-CoV-2 virions. • cVLPs induced anti-S, anti-RBD, and neutralizing antibodies in mice.

A COVID-19 vaccine candidate based on SARS-CoV-2 spike protein and immune-stimulating complexes

Spike protein from SARS-CoV-2, the etiologic agent of the COVID-19 pandemic disease, constitutes a structural protein that proved to be the main responsible for neutralizing antibody production. Thus, its sequence is highly considered for the design of candidate vaccines. Animal cell culture represents the best option for the production of subunit vaccines based on recombinant proteins since they introduce post-translational modifications that are important to mimic the natural antigenic epitopes. Particularly, the human cell line HEK293T has been explored and used for the production of biotherapeutics since the products derived from them present human-like post-translational modifications that are important for the protein's activity and immunogenicity. The aim of this study was to produce and characterize a potential vaccine for COVID-19 based on the spike ectodomain (S-ED) of SARS-CoV-2 and two different adjuvants: aluminum hydroxide (AH) and immune-stimulating complexes (ISCOMs). The S-ED was produced in sHEK293T cells using a 1-L stirred tank bioreactor operated in perfusion mode and purified. S-ED characterization revealed the expected size and morphology. High N-glycan content was confirmed. S-ED-specific binding with the hACE2 (human angiotensin-converting enzyme 2) receptor was verified. The immunogenicity of S-ED was evaluated using AH and ISCOMs. Both formulations demonstrated the presence of anti-RBD antibodies in the plasma of immunized mice, being significantly higher for the latter adjuvant. Also, higher levels of IFN-γ and IL-4 were detected after the ex vivo immune stimulation of spleen-derived MNCs from ISCOMs immunized mice. Further analysis confirmed that S-ED/ISCOMs elicit neutralizing antibodies against SARS-CoV-2. KEY POINTS: Trimeric SARS-CoV-2 S-ED was produced in stable recombinant sHEK cells in serum-free medium. A novel S-ED vaccine formulation induced potent humoral and cellular immunity. S-ED formulated with ISCOMs adjuvant elicited a highly neutralizing antibody titer.

Generation and functional evaluation of novel monoclonal antibodies targeting glycosylated human stem cell factor

Human stem cell factor (hSCF) is an early-acting growth factor that promotes proliferation, differentiation, migration, and survival in several tissues. It plays a crucial role in hematopoiesis, gametogenesis, melanogenesis, intestinal motility, and in development and recovery of nervous and cardiovascular systems. Potential therapeutic applications comprise anemia treatment, mobilization of hematopoietic stem/progenitor cells to peripheral blood, and increasing gene transduction efficiency for gene therapy. Developing new tools to characterize recombinant hSCF in most native-like form as possible is crucial to understand the complexity of its in vivo functions and for improving its biotechnological applications. The soluble domain of hSCF was expressed in HEK293 cells. Highly purified rhSCF showed great molecular mass variability due to the presence of N- and O-linked carbohydrates, and it presented a 2.5-fold increase on proliferative activity compared to bacteria-derived hSCF. Three hybridoma clones producing monoclonal antibodies (mAbs) with high specificity for the glycoprotein were obtained. 1C4 and 2D3 mAbs were able to detect bacteria-derived and glycosylated rhSCF and demonstrated to be excellent candidates to develop a sandwich ELISA assay for rhSCF quantification, with detection limits of 0.18 and 0.07 ng/ml, respectively. Interestingly, 1A10 mAb only recognized glycosylated rhSCF, suggesting that sugar moieties might be involved in epitope recognition. 1A10 mAb showed the highest binding affinity, and it constituted the best candidate for immunodetection of the entire set rhSCF glycoforms in western blot assays, and for intracellular cytokine staining. Our work shows that combining glycosylated rhSCF expression with hybridoma technology is a powerful strategy to obtain specific suitable immunochemical assays and thus improve glycoprotein-producing bioprocesses. KEY POINTS: • Soluble glycosylated human SCF exerted improved proliferative activity on UT-7 cells. • Three mAbs with high specificity targeting glycosylated human SCF were obtained. • mAbs applications comprise sandwich ELISA, western blot, and immunofluorescence assays.

Hydroxypropyl methylcellulose-based micro- and nanostructures for encapsulation of melanoidins: Effect of electrohydrodynamic processing variables on morphological and physicochemical properties

Electrohydrodynamic processing (EHDP) allows the use of a wide range of biopolymers and solvents, including food-grade biopolymers and green solvents, for the development of micro- and nanostructures. These structures present a high surface-area-to-volume ratio and different shapes and morphologies. The aim of this work was to design and produce hydroxypropyl methylcellulose (HPMC)-based micro- and nanostructures through EHD processing using green solvents, while exploring the influence of process and solution parameters, and incorporating a bioactive extracted from a food by-product. Low (LMW) and high (HMW) molecular weight HPMC have been used as polymers. The design-of-experiments methodology was used to determine the effects of process parameters (polymer concentration, flow rate, tip-to-collector distance, and voltage) of EHDP on the particle and fibre diameter, aspect ratio, diameter distribution, aspect ratio distribution, and percentage of fibre breakage. Additionally, melanoidins extracted from spent coffee grounds were encapsulated into the HPCM-based structures at a concentration of 2.5 mg melanoidins/mL of the polymer solution. Polymer solutions were characterised regarding their viscosity, surface tension and conductivity, and showed that the incorporation of melanoidins increased the viscosity and conductivity values of the polymer solutions. The developed structures were characterised regarding their thermal properties, crystallinity and morphology before and after melanoidin incorporation and it was observed that melanoidin incorporation did not significantly influence the characteristics of the produced micro- and nanostructures. Based on the results, it is possible to envision the use of the produced micro- and nanostructures in a wide range of applications, both in food and biomedical fields.

Development, Production, and Characterization of Hepatitis B Subviral Envelope Particles as a Third-Generation Vaccine

Vaccination still represents the most efficient and inexpensive strategy in the control of hepatitis B virus (HBV) infection. However, about 10% of the population vaccinated with the current S yeast-derived vaccine fail to induce an adequate immune response. Our group has developed a new-generation hepatitis B vaccine candidate composed by the three surface proteins of the HBV. Here we describe the methods to develop and characterize a stable CHO-K1 recombinant cell line able to produce and secrete hepatitis B subviral envelope particles (HBV-SVPs) containing L and M glycoproteins in addition to S glycoprotein. In addition, Western blot and immunogold electron microscopy techniques to evaluate the size, morphology, and composition of the particles are explained. Finally, immunization protocols are described in order to study the immunogenicity of HBV-SVPs and the ability of the antibodies triggered by these particles to recognize the binding site of HBV with the hepatocyte.

Sleep Problems Are Related to a Worse Quality of Life and a Greater Non-Motor Symptoms Burden in Parkinson's Disease

INTRODUCTION

The aim of the present study was to examine the frequency of self-reported sleep problems and their associated factors in a large cohort of PD patients.

METHODS

PD patients and controls, recruited from 35 centers of Spain from the COPPADIS cohort were included in this cross-sectional study. Sleep problems were assessed by the Spanish version of the Parkinson's disease Sleep Scale version 1 (PDSS-1). An overall score below 82 or a score below 5 on at least 1 item was defined as sleep problems.

RESULTS

The frequency of sleep problems was nearly double in PD patients compared to controls: 65.8% (448/681) vs 33.5% (65/206) (p < 0.0001). Mean total PDSS score was lower in PD patients than controls: 114.9 ± 28.8 vs 132.8 ± 16.3 (p < 0.0001). Quality of life (QoL) was worse in PD patients with sleep problems compared to those without: PDQ-39SI, 19.3 ± 14 vs 13 ± 11.6 (p < 0.0001); EUROHIS-QoL8, 3.7 ± 0.5 vs 3.9 ± 0.5 (p < 0.0001). Non-motor symptoms burden (NMSS; OR = 1.029; 95%CI 1.015-1.043; p < 0.0001) and impulse control behaviors (QUIP-RS; OR = 1.054; 95%CI 1.009-1.101; p = 0.018) were associated with sleep problems after adjustment for age, gender, disease duration, daily equivalent levodopa dose, H&Y, UPDRS-III, UPDRS-IV, PD-CRS, BDI-II, NPI, VAS-Pain, VAFS, FOGQ, and total number of non-antiparkinsonian treatments.

CONCLUSION

Sleep problems were frequent in PD patients and were related to both a worse QoL and a greater non-motor symptoms burden in PD. These findings call for increased awareness of sleep problems in PD patients.

Development of a suitable manufacturing process for production of a bioactive recombinant equine chorionic gonadotropin (reCG) in CHO-K1 cells

Equine chorionic gonadotropin (eCG) is a heterodimeric glycoprotein hormone produced by pregnant mares that has been used to improve reproductive performance in different domestic species. Several strategies to produce the hormone in a recombinant way have been reported; nevertheless, no approach has been able to produce a recombinant eCG (reCG) with significant in vivo bioactivity or in sufficient quantities for commercial purposes. For this reason, the only current product available on the market consists of partially purified preparations from serum of pregnant mares (PMSG). Herein, we describe a highly efficient process based on third-generation lentiviral vectors as delivery method for the production of reCG in suspension CHO-K1 cells, with productivities above 20 IU 10⁶ cell^-1.d^-1 and 70% purification yields after one purification step. Importantly, reCG demonstrated biological activity in cattle, since around 30 μg of reCG were needed to exert the same biologic effect of 400 IU of PMSG in an ovulation synchronization protocol. The results obtained demonstrate that the developed strategy represents an attractive option for the production of reCG and constitutes an auspicious alternative for the replacement of animals as a source of PMSG.

Characterization of hepatitis B virus surface antigen particles expressed in stably transformed mammalian cell lines containing the large, middle and small surface protein

Vaccination still represents the most efficient and inexpensive strategy in the control of hepatitis B virus (HBV) infection. However, about 10% of the population vaccinated with the current yeast derived vaccine, consisting of the non-glycosylated form of the small envelope protein (S) of the HBV, fail to display an adequate immune response. Therefore, there is a need for the development of new vaccines with enhanced immunogenicity. On this regard, new generation vaccines containing L and preS2-containing HBV surface proteins in addition to S, have proven to be able to bypass the lack of response of the standard vaccine. In this work, we describe the development of stable recombinant CHO-K1 and HEK293 cell lines able to produce and secrete hepatitis B subviral envelope particles (HBV-SVPs) composed by the three surface proteins of the HBV. In turn, we demonstrated that these particles induced a specific humoral immune response in experimental animals and triggered the production of antibodies with the ability to recognize the binding site of HBV with the hepatocyte. Thus, these HBV-SVPs represent a promising candidate as a new generation vaccine in order to enhance the immunogenicity of the conventional yeast derived HBV vaccine.

Rabies VLPs adjuvanted with saponin-based liposomes induce enhanced immunogenicity mediated by neutralizing antibodies in cattle, dogs and cats

We carried out an investigation on rabies virus-like particles (RV-VLPs) expressed in HEK293 cells using serum free medium. These RV-VLPs were formulated with two different adjuvants in order to analyse the enhancement of the triggered immune response and its stability. In experiments in mice, RV-VLPs showed an enhanced humoral immune response when injected with adjuvant, in contrast to the obtained for the RV-VLPs without adjuvant addition. Besides, higher titers of neutralizing antibodies were induced when RV-VLPs were formulated with LipoSap® in comparison with the obtained with Alhydrogel®. At the same time, the positive effect of this adjuvant in vaccine's potency and stability was demonstrated, showing that LipoSap® significantly increases the value obtained in NIH efficiency test for rabies vaccine, and proving that this value is maintained after 15 months storage at 4 °C. Further, we showed that RV-VLPs induces an immune response based on neutralizing antibodies when cat, dogs and bovines were vaccinated with only one dose of RV-VLPs. These results demonstrated that this vaccine candidate could be applied for the prevention of rabies in pets as well as for the control of paralytic rabies in cattle.

Free-running cardiac magnetic resonance fingerprinting: Joint T1/T2 map and Cine imaging

PURPOSE

To develop and evaluate a novel non-ECG triggered 2D magnetic resonance fingerprinting (MRF) sequence allowing for simultaneous myocardial T₁ and T₂ mapping and cardiac Cine imaging.

METHODS

Cardiac MRF (cMRF) has been recently proposed to provide joint T₁/T₂ myocardial mapping by triggering the acquisition to mid-diastole and relying on a subject-dependent dictionary of MR signal evolutions to generate the maps. In this work, we propose a novel "free-running" (non-ECG triggered) cMRF framework for simultaneous myocardial T₁ and T₂ mapping and cardiac Cine imaging in a single scan. Free-running cMRF is based on a transient state bSSFP acquisition with tiny golden angle radial readouts, varying flip angle and multiple adiabatic inversion pulses. The acquired data is retrospectively gated into several cardiac phases, which are reconstructed with an approach that combines parallel imaging, low rank modelling and patch-based high-order tensor regularization. Free-running cMRF was evaluated in a standardized phantom and ten healthy subjects. Comparison with reference spin-echo, MOLLI, SASHA, T₂-GRASE and Cine was performed.

RESULTS

T₁ and T₂ values obtained with the proposed approach were in good agreement with reference phantom values (ICC(A,1) > 0.99). Reported values for myocardium septum T₁ were 1043 ± 48 ms, 1150 ± 100 ms and 1160 ± 79 ms for MOLLI, SASHA and free-running cMRF respectively and for T₂ of 51.7 ± 4.1 ms and 44.6 ± 4.1 ms for T₂-GRASE and free-running cMRF respectively. Good agreement was observed between free-running cMRF and conventional Cine 2D ejection fraction (bias = -0.83%).

CONCLUSION

The proposed free-running cardiac MRF approach allows for simultaneous assessment of myocardial T₁ and T₂ and Cine imaging in a single scan.

Cardiac Magnetic Resonance Fingerprinting: Technical Developments and Initial Clinical Validation

PURPOSE OF REVIEW

Magnetic resonance imaging (MRI) has enabled non-invasive myocardial tissue characterization in a wide range of cardiovascular diseases by quantifying several tissue specific parameters such as T1, T2, and T2* relaxation times. Simultaneous assessment of these parameters has recently gained interest to potentially improve diagnostic accuracy and enable further understanding of the underlying disease. However, these quantitative maps are usually acquired sequentially and are not necessarily co-registered, making multi-parametric analysis challenging. Magnetic resonance fingerprinting (MRF) has been recently introduced to unify and streamline parametric mapping into a single simultaneous, multi-parametric, fully co-registered, and efficient scan. Feasibility of cardiac MRF has been demonstrated and initial clinical validation studies are ongoing. Provide an overview of the cardiac MRF framework, recent technical developments and initial undergoing clinical validation.

RECENT FINDINGS

Cardiac MRF has enabled the acquisition of co-registered T1 and T2 maps in a single, efficient scan. Initial results demonstrate feasibility of cardiac MRF in healthy subjects and small patient cohorts. Current in vivo results show a small bias and comparable precision in T1 and T2 with respect to conventional clinical parametric mapping approaches. This bias may be explained by several confounding factors such as magnetization transfer and field inhomogeneities, which are currently not included in the cardiac MRF model. Initial clinical validation for cardiac MRF has demonstrated good reproducibility in healthy subjects and heart transplant patients, reduced artifacts in inflammatory cardiomyopathy patients and good differentiation between hypertrophic cardiomyopathy and healthy controls. Cardiac MRF has emerged as a novel technique for simultaneous, multi-parametric, and co-registered mapping of different tissue parameters. Initial efforts have focused on enabling T1, T2, and fat quantification; however this approach has the potential of enabling quantification of several other parameters (such as T2*, diffusion, perfusion, and flow) from a single scan. Initial results in healthy subjects and patients are promising, thus further clinical validation is now warranted.

A simplified roller bottle platform for the production of a new generation VLPs rabies vaccine for veterinary applications

Rabies is a neglected disease with an estimated annual mortality of 55,000 human deaths, affecting mainly low-income countries. Over 95% of these cases result from virus transmission through the bite of infected dogs and for this reason there is a real need for a cheap and effective rabies veterinary vaccine to be used in mass vaccination campaigns. In this work, we describe the establishment of a simple platform for the production of a virus-like particles based rabies vaccine using mammalian cells and roller bottles as culture system. Adherent cells were cultured during more than 15 days and VLPs were continuously produced and secreted to the culture supernatant. Immunogenicity and protective efficacy of VLPs were tested through rabies virus neutralizing antibody test and NIH potency test. These viral particles induced high titer of long lasting neutralizing antibodies and protected mice against active virus challenge. Therefore, this development represents a promising platform for the production of a new generation and virus-free rabies vaccine candidate for veterinary applications.

Considerations on the Taxonomy of the Genus Arhuaco Adams and Bernard 1977, and its Relationships with the Genus Pronophila Doubleday [1849] (Nymphalidae, Satyrinae)

Arhuaco Adams & Bernard (1977) is one of the least known genera of Neotropical Satyrinae. It comprises two species and presents an unusual disjunct distribution, with A. ica Adams & Bernard (1977), endemic to the isolated Colombian Sierra Nevada de Santa Marta, and A. dryadina (Schaus 1913) found in the mountains of Costa Rica and Panama. Here, the female of A. dryadina is described, and a new generic diagnosis is presented. Affinities with other genera of the subtribe Pronophilina, in particular the potential closest relatives, such as Pronophila Doubleday (1849), are investigated based on morphological, molecular, ecological, and behavioral data. Results from molecular and morphological sources are incongruent. Molecular data indicate that Arhuaco is paraphyletic, with A. dryadina segregating within the Pronophila clade. Morphological data, by contrast, indicate a closer affinity between the two species currently placed in Arhuaco, favoring the monophyly of the genus, and show no consistent synapomorphies for Arhuaco + Pronophila. A vicariance biogeographical scenario is evaluated.

Production of Therapeutic Enzymes by Lentivirus Transgenesis

Since ERT for several LSDs treatment has emerged at the beginning of the 1980s with Orphan Drug approval, patients' expectancy and life quality have been improved. Most LSDs treatment are based on the replaced of mutated or deficient protein with the natural or recombinant protein.One of the main ERT drawback is the high drug prices. Therefore, different strategies trying to optimize the global ERT biotherapeutic production have been proposed. LVs, a gene delivery tool, can be proposed as an alternative method to generate stable cell lines in manufacturing of recombinant proteins. Since LVs have been used in human gene therapy, clinical trials, safety testing assays and procedures have been developed. Moreover, one of the main advantages of LVs strategy to obtain manufacturing cell line is the short period required as well as the high protein levels achieved.In this chapter, we will focus on LVs as a recombinant protein production platform and we will present a case study that employs LVs to express in a manufacturing cell line, alpha-Galactosidase A (rhαGAL), which is used as ERT for Fabry disease treatment.

Influence of soil conditions on the distribution coefficients of 226Ra in natural soils

In order to clarify some of the assumptions and approximations about the use of the distribution coefficient K_d for ²²⁶Ra in soils, a systematic study has been performed using centrifugation to extract the soil solution. The separated fractions of the soil solution have different kinetics with respect to the sorption process in the soil, which may in turn condition the final chemical composition and even the speciation of the radionuclides in solution. In the experimental design of this study three factors were considered: the moisture level in the incubation process, incubation time and the speed of centrifugation. Also, three levels were chosen for each factor. In order to analyze the influence of the structural characteristics of the soil, this study was performed with three textural fractions: coarse sand, fine sand, and silt and clay, obtained from an only soil. Also, the soil was naturally enriched with radionuclides of the ²³⁸U series. An analysis of variance (ANOVA) was performed in order to assess the influence of the factors studied on the distribution coefficient of ²²⁶Ra. The results indicate that different behaviors can be observed depending on the structural characteristic of the soil. In the case of particle size, the soil with the largest grain size showed that the incubation process parameters influence the equilibrium level achieved, while in the case of the smallest edaphic particles, radium is not homogeneously distributed in the soil solution and the K_d value is dependent on the speed of centrifugation.

NG2 antigen is involved in leukemia invasiveness and central nervous system infiltration in MLL-rearranged infant B-ALL

Mixed-lineage leukemia (MLL)-rearranged (MLLr) infant B-cell acute lymphoblastic leukemia (iMLLr-B-ALL) has a dismal prognosis and is associated with a pro-B/mixed phenotype, therapy refractoriness and frequent central nervous system (CNS) disease/relapse. Neuron-glial antigen 2 (NG2) is specifically expressed in MLLr leukemias and is used in leukemia immunophenotyping because of its predictive value for MLLr acute leukemias. NG2 is involved in melanoma metastasis and brain development; however, its role in MLL-mediated leukemogenesis remains elusive. Here we evaluated whether NG2 distinguishes leukemia-initiating/propagating cells (L-ICs) and/or CNS-infiltrating cells (CNS-ICs) in iMLLr-B-ALL. Clinical data from the Interfant cohort of iMLLr-B-ALL demonstrated that high NG2 expression associates with lower event-free survival, higher number of circulating blasts and more frequent CNS disease/relapse. Serial xenotransplantation of primary MLL-AF4⁺ leukemias indicated that NG2 is a malleable marker that does not enrich for L-IC or CNS-IC in iMLLr-B-All. However, NG2 expression was highly upregulated in blasts infiltrating extramedullar hematopoietic sites and CNS, and specific blockage of NG2 resulted in almost complete loss of engraftment. Indeed, gene expression profiling of primary blasts and primografts revealed a migratory signature of NG2⁺ blasts. This study provides new insights on the biology of NG2 in iMLLr-B-ALL and suggests NG2 as a potential therapeutic target to reduce the risk of CNS disease/relapse and to provide safer CNS-directed therapies for iMLLr-B-ALL.

High yield process for the production of active human α-galactosidase a in CHO-K1 cells through lentivirus transgenesis

Fabry disease is an X-linked recessive disorder caused by a deficiency in lysosomal α-Galactosidase A. Currently, two enzyme replacement therapies (ERT) are available. However, access to orphan drugs continues to be limited by their high price. Selection of adequate high-expression systems still constitutes a challenge for alleviating the cost of treatments. Several strategies have been implemented, with varying success, trying to optimize the production process of recombinant human α-Galactosidase A (rhαGAL) in Chinese hamster ovary (CHO-K1) cells. Herein, we describe for the first time the application of a strategy based on third-generation lentiviral particles (LP) transduction of suspension CHO-K1 cells to obtain high-producing rhαGAL clones (3.5 to 59.4 pg cell^-1 d^-1 ). After two purification steps, the active enzyme was recovered (2.4 × 10⁶ U mg^-1 ) with 98% purity and 60% overall yield. Michaelis-Menten analysis demonstrated that rhαGAL was capable of hydrolyzing the synthetic substrate 4MU-α-Gal at a comparable rate to Fabrazyme®, the current CHO-derived ERT available for Fabry disease. In addition, rhαGAL presented the same mannose-6-phosphate (M6P) content, about 40% higher acid sialic amount and 33% reduced content of the immunogenic type of sialic acid (Neu5Gc) than the corresponding ones for Fabrazyme®. In comparison with other rhαGAL production processes reported to date, our approach achieves the highest rhαGAL productivity preserving adequate activity and glycosylation pattern. Even more, considering the improved glycosylation characteristics of rhαGAL, which might provide advantages regarding pharmacokinetics, our enzyme could be postulated as a promising alternative for therapeutic use in Fabry disease. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1334-1345, 2017.

Free breathing whole-heart 3D CINE MRI with self-gated Cartesian trajectory

Purpose

To present a method that uses a novel free-running self-gated acquisition to achieve isotropic resolution in whole heart 3D Cartesian cardiac CINE MRI.

Material and methods

3D cardiac CINE MRI using navigator gating results in long acquisition times. Recently, several frameworks based on self-gated non-Cartesian trajectories have been proposed to accelerate this acquisition. However, non-Cartesian reconstructions are computationally expensive due to gridding, particularly in 3D. In this work, we propose a novel highly efficient self-gated Cartesian approach for 3D cardiac CINE MRI. Acquisition is performed using CArtesian trajectory with Spiral PRofile ordering and Tiny golden angle step for eddy current reduction (so called here CASPR-Tiger). Data is acquired continuously under free breathing (retrospective ECG gating, no preparation pulses interruption) for 4–5 min and 4D whole-heart volumes (3D + cardiac phases) with isotropic spatial resolution are reconstructed from all available data using a soft gating technique combined with temporal total variation (TV) constrained iterative SENSE reconstruction.

Results

For data acquired on eight healthy subjects and three patients, the reconstructed images using the proposed method had good contrast and spatio-temporal variations, correctly recovering diastolic and systolic cardiac phases. Non-significant differences (P > 0.05) were observed in cardiac functional measurements obtained with proposed 3D approach and gold standard 2D multi-slice breath-hold acquisition.

Conclusion

The proposed approach enables isotropic 3D whole heart Cartesian cardiac CINE MRI in 4 to 5 min free breathing acquisition.

•

A novel self-gated 3D Cartesian acquisition is proposed for free breathing whole-heart cardiac MRI

•

The proposed framework has efficient k-space sampling, better eddy current performance and high computational efficiency

•

The Proposed method is able to achieve high spatio-temporal resolution 3D cardiac CINE

•

The proposed method only requires four to five minute free breathing scan

Rational design of nitrofuran derivatives: Synthesis and valuation as inhibitors of Trypanosoma cruzi trypanothione reductase

The rational design and synthesis of a series of 5-nitro-2-furoic acid analogues are presented. The trypanocidal activity against epimastigote forms of Trypanosoma cruzi and the toxic effects on human HeLa cells were tested. Between all synthetic compounds, three of thirteen had an IC₅₀ value in the range of Nfx, but compound 13 exhibited an improved effect with an IC₅₀ of 1.0 ± 0.1 μM and a selective index of 70 in its toxicity against HeLa cells. We analyzed the activity of compounds 8, 12 and 13 to interfere in the central redox metabolic pathway in trypanosomatids, which is dependent of reduced trypanothione as the major pivotal thiol. The three compounds behaved as better inhibitors of trypanothione reductase than Nfx (Ki values of 118 μM, 61 μM and 68 μM for 8, 12 and 13, respectively, compared with 245 μM for Nfx), all following an uncompetitive enzyme inhibition pattern. Docking analysis predicted a binding of inhibitors to the enzyme-substrate complex with binding energy calculated in-silico that supports such molecular interaction.

Is it possible to prevent recurrent vulvovaginitis? The role of Lactobacillus plantarum I1001 (CECT7504)

The purpose of this study was to prospectively evaluate the impact of the use of L. plantarum I1001 applied vaginally on Vulvovaginal Candidiasis (VVC) time-until-recurrence after treatment with single-dose vaginal clotrimazole. This was a clinical open-label, prospective study of two non-randomized parallel cohorts with symptomatic acute VVC: (1) 33 sexually active women 18–50 years old, prescribed a standard single-dose 500 mg vaginal tablet of clotrimazole followed by vaginal tablets with L. plantarum I1001 as adjuvant therapy, and (2) 22 women of similar characteristics but prescribed single-dose clotrimazole only. Use of the probiotic and factors that might influence recurrence risk (age, recurrent VVC within previous year, antibiotic prior to study enrolment, diaphragm or IUD contraception, among others) were included in a multivariate Cox regression model to adjust for potential between-cohort differences. Probiotic use was associated with a three-fold reduction in the adjusted risk of recurrence (HR [95 %CI]: 0.30 [0.10–0.91]; P = 0.033). Adjusted free-survival recurrence was 72.83 % and 34.88 % for the probiotic and control groups, respectively. A higher cumulative recurrence was also observed in cases with use of antibiotics prior to enrolment (HR [95 %CI]: 10.46 [2.18–50.12]; P = 0.003). Similar findings were found at six months after azole treatment in women with RVVC. Overall, good compliance with the probiotic was reported for 91.3 % of women. The study suggests that follow-up therapy with vaginal tablets with L. plantarum I1001 could increase the effectiveness of single-dose 500 mg clotrimazole at preventing recurrence of VVC, an effect that was also observed in women with recurrent vulvovaginal candidiasis (RVVC) after six months of azole treatment.

Spectral reflectance data of a high temperature stable solar selective coating based on MoSi2 -Si3N4

Data of optical performance, thermal stability and ageing are given for solar selective coatings (SSC) based on a novel MoSi2-Si3N4 absorbing composite. SSC have been prepared as multilayer stacks formed by silver as metallic infrared reflector, a double layer composite and an antireflective layer (doi: 10.1016/j.solmat.2016.04.001 [1]). Spectroscopic reflectance data corresponding to the optical performance of samples after moderate vacuum annealing at temperatures up to 600 °C and after ageing test of more than 200 h with several heating-cooling cycles are shown here.

[Factors modulating food intake and energy expenditure prior to liver transplantation]

BACKGROUND

There is a high prevalence of nutritional disorders in patients with liver cirrhosis (LC). This study was designed to assess the relationships between liver function, IFG-I/IGFBP-3, nutritional status, leptin, ghrelin and glucagon in 21 patients waiting for liver transplantation (LT).

METHODS

We studied 21 men aged 56±2.1 years who were on the LT list. They were classified according to Child-Pugh(CP) score from low to high liver dysfunction in CPA (n=4),CPB (n=11) and CPC (n=6). Body mass index (BMI) was calculated and body fat (%) was measured by air-displacement plethysmography. Resting energy expenditure (REE) and its variation over Harris-Benedict values (GER%) were assessed by indirect calorimetry. Fasting serum samples were taken to measure albumin, glucose, insulin, HbA1c, leptin, total ghrelin,glucagon, IGF-I and IGFBP3.

RESULTS

There were no differences in fat % and leptin values in the three groups according to CP classification. The CPC group showed higher ghrelin values than CPA and CPB(p<0.05). All groups displayed high glucagon levels and GER%values superior to 100%. Positive correlations were found between glucagon and GER% (r=0.56; p<0.01) and between glucagon and ghrelin values (r=0.66; p<0.01). IGF-I and IGFBP3 were low in all groups and showed a positive correlation with plasma albumin (r=0.52; p<0.05 and r=0.45; p<0.05 respectively).

CONCLUSIONS

These results show an increase in ghrelin plasma values in patients with severe liver dysfunction. Hyperglucagonemia was correlated with GER%, supporting a role of glucagon in the hypermetabolic state associated to LC,raising the possibility of becoming a therapeutic target. The measurement of IGF-I/IGFBP3 represents a good marker of liver function in patients with LC.

Antidepressants in Parkinson's disease. Recommendations by the movement disorder study group of the Neurological Association of Madrid

INTRODUCTION

Although antidepressants are widely used in Parkinson's disease (PD), few well-designed studies to support their efficacy have been conducted.

DEVELOPMENT

These clinical guidelines are based on a review of the literature and the results of an AMN movement disorder study group survey.

CONCLUSIONS

Evidence suggests that nortriptyline, venlafaxine, paroxetine, and citalopram may be useful in treating depression in PD, although studies on paroxetine and citalopram yield conflicting results. In clinical practice, however, selective serotonin reuptake inhibitors are usually considered the treatment of choice. Duloxetine may be an alternative to venlafaxine, although the evidence for this is less, and venlafaxine plus mirtazapine may be useful in drug-resistant cases. Furthermore, citalopram may be indicated for the treatment of anxiety, atomoxetine for hypersomnia, trazodone and mirtazapine for insomnia and psychosis, and bupropion for apathy. In general, antidepressants are well tolerated in PD. However, clinicians should consider the anticholinergic effect of tricyclic antidepressants, the impact of serotonin-norepinephrine reuptake inhibitors on blood pressure, the extrapyramidal effects of antidepressants, and any potential interactions between monoamine oxidase B inhibitors and other antidepressants.

Development of Rabies Virus-Like Particles for Vaccine Applications: Production, Characterization, and Protection Studies

Rabies is a viral infection of the central nervous system for which vaccination is the only treatment possible. Besides preexposure, vaccination is highly recommended for people living in endemic areas, veterinarians, and laboratory workers. Our group has developed rabies virus-like particles (RV-VLPs) with immunogenic features expressed in mammalian cells for vaccine applications. In this chapter the methods to obtain and characterize a stable HEK293 cell line expressing RV-VLPs are detailed. Further, analytical ultracentrifugation steps to purify the obtained VLPs are developed, as well as western blot, dynamic light scattering, and immunogold electron microscopy to analyze the size, distribution, shape, and antigenic conformation of the purified particles. Finally, immunization protocols are described to study the immunogenicity of RV-VLPs.

C-reactive protein, haptoglobin and Pig-Major acute phase protein profiles of pigs infected experimentally by different isolates of porcine reproductive and respiratory syndrome virus

Porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV) is the etiologic agent of PRRS, one of the most important diseases in swine worldwide. In the present work, the effects of different PRRSV strains were tested on a piglet experimental model to study the induced acute phase response. For this purpose, pigs (n=15 for each group) were intranasally inoculated with one of five PRRSV strains (isolates EU10, 12, 17, 18 from genotype 1 and isolate JA-142 from genotype 2). The acute phase response was monitored by measuring acute phase proteins (APPs). Specifically, the serum concentration of haptoglobin (Hp), C-reactive protein (CRP) and Pig-Major Acute Protein (Pig-MAP) was determined at 0, 3, 6, 9, 12, 15, 18 and 21 days p.i. Clinical signs and growth performance were also monitored during the experiment. All animals became viremic after inoculation during the study period. The APP response was heterogeneous and dependent on the strain, being strains EU10, EU 18 and JA-142 those that induced the highest response and the strongest clinical signs. In general, Hp was the most sensitive biomarker for PRRSV infection, CRP behaved as moderate and Pig-MAP was the less responsive during the course of PRRSV experimental infection. Hp and CRP were significantly discriminatory between infected and control pigs, but not Pig-MAP.

Experience in retake analysis for digital mammography at a university hospital

Data from one digital mammograph (flat detector active area of 19.2 × 23 cm(2)) were collected over a 1-year period using locally developed software in order to evaluate retakes, their rates, their causes and the possible measures to reduce their occurrence. Among them, 7.1 % of the images were marked as repetitions, and in 16 % of the studies, at least one image was repeated. When evaluating causes of retakes, the primary cause was incorrect positioning (49 %), closely followed by additional retakes in cases of large breasts (44 %). When dealing with large breasts and using a small flat panel, additional images were necessary to fully visualise the breast, and as a consequence, some breast regions received repeated radiation exposure. Moreover, a small detector increases retakes in breasts slightly wrongly positioned. To try and reduce the retake rate, it is important to plan training sessions based on images selected from the retake analysis.

Immunogenic virus-like particles continuously expressed in mammalian cells as a veterinary rabies vaccine candidate

Rabies is one of the most lethal infectious diseases in the world, with a mortality approaching 100%. There are between 60,000 and 70,000 reported annual deaths, but this is probably an underestimation. Despite the fact that there are vaccines available for rabies, there is a real need of developing more efficacious and cheaper vaccines. This is particularly true for veterinary vaccines because dogs are still the main vector for rabies transmission to human beings. In a previous work, we described the development and characterization of rabies virus-like particles (RV-VLPs) expressed in HEK293 cells. We showed that RV-VLPs are able to induce a specific antibodies response. In this work, we show that VLPs are able to protect mice against virus challenge. Furthermore, we developed a VLPs expressing HEK-293 clone (sP2E5) that grows in serum free medium (SFM) reaching high cell densities. sP2E5 was cultured in perfusion mode in a 5 L bioreactor for 20 days, and the RV-VLPs produced were capable of triggering a protective immune response without the need of concentration or adjuvant addition. Further, these VLPs are able to induce the production of rabies virus neutralizing antibodies. These results demonstrate that RV-VLPs are a promising rabies vaccine candidate.