High Cell Concentrations Research Articles

Process intensification of the baculovirus expression vector system using a perfusion process with a low multiplicity of infection at high cell concentrations.

The emergence of new viruses and the spread of existing pathogens necessitate efficient vaccine production methods. The baculovirus expression vector system (BEVS) is an efficient and scalable system for subunit and virus-like particle vaccine production and gene therapy vectors. However, current production processes are often limited to low cell concentrations (1-4 × 106 cells/mL) in fed-batch mode. To improve the volumetric productivity of the BEVS, a medium exchange strategy was investigated. Screening experiments were performed to test baculovirus (expressing green fluorescent protein; GFP) infection and productivity of insect cell cultures infected at high cell concentration (1-2 × 107 cells/mL), showing that infection at high cell concentrations was possible with medium exchange. Next, duplicate perfusion runs with baculovirus infection were performed using a cell concentration upon infection (CCI) of 1.2 × 107 cells/mL and a multiplicity of infection (MOI) of 0.01, reaching a maximum viable cell concentration of 2.8 × 107 cells/mL and a maximum GFP production of 263 mg/L. The volumetric productivity of these perfusion runs was 4.8 times higher than for reference batch processes with a CCI of 3 × 106 cells/mL and an MOI of 1. These results demonstrate that process intensification can be achieved for the BEVS by implementing perfusion, resulting in a higher volumetric productivity.

Biodegradation of Deep Eutectic Solvent Pre-Treated Natural Rubber Gloves by Klebsiella aerogenes: A Sustainable Approach to Rubber Waste Management

This study investigates the potential of deep eutectic solvents (DES) to enhance the biodegradation of natural rubber gloves (NRG) by Klebsiella aerogenes. Choline chloride and urea (ChCl: urea) DES was employed to pre-treat NRG at various temperatures (80°C to 140°C) and durations (0.5h to 5h). Pre-treated rubber (p-NRG) underwent significant physical and chemical changes, enhancing its biodegradability. Analytical techniques such as dry weight analysis, bacteria cell concentration, FTIR TGA, and SEM were used to characterize the pre-treated and biodegraded samples. The results have demonstrated a significant weight loss and structural modifications in p-NRG, with the highest degradation efficiency of 43% observed at 140°C for 5hours of pretreatment before biodegradation. Meanwhile, merely 17% of biodegradation was observed in biodegradation without pre-treatment. DES pre-treatment notably enhanced NRG biodegradability, achieving a 50.6% weight loss at pH 7 and 35°C. The highest cell concentration, 0.75g/L, was recorded in the second week of the biodegradation process. Results has indicated that the maximum protein concentration of 697.3µg/mL, along with the highest enzyme activities for laccase and manganese peroxidase (MnP) at 0.46 ± 0.05 IU and 0.30 ± 0.05 IU respectively, were recorded at the second week of the biodegradation process. DES pre-treatment has significantly improved the biodegradability of NRG by Klebsiella aerogenes, offering a promising and eco-friendly solution for rubber waste management.

Detection and quantification of ergothioneine in human serum using surface enhanced Raman scattering (SERS).

Ergothioneine (ERG) is a natural sulfur-containing amino acid found in many organisms, including humans. It accumulates at high concentrations in red blood cells and is distributed to various organs, including the brain. ERG has numerous health benefits and antioxidant capabilities, and it has been linked to various human physiological processes, such as anti-inflammatory, neuroprotective, and anti-aging effects. Accurate, rapid, and cost-effective quantification of ERG levels in human biofluids is crucial for understanding its role in oxidative stress-related diseases. Surface-enhanced Raman scattering (SERS) is an effective approach for measuring compounds at concentrations similar to those at which ERG is present in serum. However, while SERS has been used to characterize or detect ERG, quantification has not yet been achieved due to the variability in the signal enhancement that can arise during sample preparation and analysis. This study introduces a highly efficient and reliable technique for quickly (20 min is typical per sample) measuring ERG levels in human serum using SERS. This employs an internal standard highly specific for ERG which resulted in limit of quantification values of 0.71 μM. To validate this approach, we analysed real human serum with unknown ERG levels as a blind test set and primary reference levels of ERG were produced using a targeted UHPLC-MS/MS reference method.

Novel Study of Reaction Kinetics and Mass Transfer in Bioreactor Modelling: Prediction of Bioethanol Fermentation Performance by Saccharomyces cerevisiae on Continuous Fixed Bed Biofilm Plug Flow Reactor

Bioethanol implementation as a renewable fuel has yielded economic, social, and environmental benefits, including reduced fossil fuel consumption, enhanced energy diversity and supply security, lower greenhouse gas emissions, and support for agricultural communities. These impacts underscore the importance of advancing innovation and optimizing processes to increase bioethanol production. Therefore, basic knowledge of chemical engineering in bioethanol fermentation is important to be learnt as a preliminary study, such as reaction kinetics and transport phenomena. This work studies the reaction kinetics and mass transfer in continuous fixed bed biofilm plug flow reactor modelling to predict anaerobic Saccharomyces cerevisiae fermentation performance, which is still not studied comprehensively. This modelling provides an overview of the influence of various independent variables, namely temperature, initial substrate concentration, cell concentration, superficial flow rate, reactor diameter, and solid particle diameter on various dependent variables, namely final product concentration, residence time, reactor length, reactor volume, product productivity, and pressure drop. The most sensitive parameters related to product productivity are temperature and cell concentration, so in its implementation, the temperature must be controlled at its optimum temperature, and the inoculum must be prepared with high cell concentration. For the next study, it is recommended to study the optimization of reactor design and operation (i.e. the pumping system, cooling system, and pH control of the reactor) and the implementation of the reactor on the plant scale. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Progress in the application of auto-concentrated growth factor (CGF) in wound repair.

Auto-concentrated growth factor (CGF) constitutes the latest generation of plasma extract, and has high concentrations of growth factors and white blood cells. Due to the continuous variable speed centrifugation used during preparation, the tensile strength of the fibrin is also higher. CGF preparation does not involve the use of animal serum, minimizing the risk of infection and immune rejection. Therefore, it has wide potential applications in various fields of regenerative medicine. This paper summarizes the history behind CGF development, reviews the clinical applications and research progress concerning single CGF therapy and CGF used in combination with other treatments in multiple wound repair, and summarizes its potential value as therapeutic agent. Finally, some constructive suggestions and research perspectives for the application of CGF in wound healing are put forward. The available evidence indicates that CGF can promote the healing of chronic refractory wounds and acute wound, promote the growth of granulation, accelerate the speed and improve the quality of wound healing, reduce scar formation, minimize the need for repeated wound dressing, and ameliorate the pain experienced by patients.

Integrating 3D Bioprinting and Organoids to Better Recapitulate the Complexity of Cellular Microenvironments for Tissue Engineering.

Organoids, with their capacity to mimic the structures and functions of human organs, have gained significant attention for simulating human pathophysiology and have been extensively investigated in the recent past. Additionally, 3D bioprinting, as an emerging bio-additive manufacturing technology, offers the potential for constructing heterogeneous cellular microenvironments, thereby promoting advancements in organoid research. In this review, the latest developments in 3D bioprinting technologies aimed at enhancing organoid engineering are introduced. The commonly used bioprinting methods and materials for organoids, with a particular emphasis on the potential advantages of combining 3D bioprinting with organoids are summarized. These advantages include achieving high cell concentrations to form large cellular aggregates, precise deposition of building blocks to create organoids with complex structures and functions, and automation and high throughput to ensure reproducibility and standardization in organoid culture. Furthermore, this review provides an overview of relevant studies from recent years and discusses the current limitations and prospects for future development.

Enhancing Scalability and Consistency in Pulsed Electric Field Processing of Microalgae: Integrating Single-Cell Suspension Rheology and Multiphysics Simulation

Emerging extraction technologies such as microsecond pulsed electric field (μsPEF) offer an energy-efficient and gentle method for downstream processing of single cells. However, attaining consistent processing outcomes in continuous PEF systems across different scales is challenging due to variations in cell residence times caused by cell concentration and flow-dependent rheological behavior. This study employed COMSOL Multiphysics® simulations to model rheological changes in high-density heterotrophically grown Auxenochlorella protothecoides microalgae suspensions. The model was designed to precisely estimate residence times for consistent μsPEF treatment and increased processing capacity at high flow rates and cell concentrations. Implementing the simulated residence times into experimental validations achieved consistent treatment outcomes, resulting in 86 ± 4% of cells being permeabilized and increased processing capacity from 21 to 300 mL min-1. Higher cell concentrations led to increased energy input and decreased protein extraction yields, indicating complex underlying permeabilization and diffusion processes during and after treatment. This work advances scalable and consistent μsPEF technology for single-cell downstream processing by applying cell suspension rheology and residence time simulations.

Light intensity effects on bioproduct recovery from fuel synthesis wastewater using purple phototrophic bacteria in a hybrid biofilm-suspended growth system

This research looked at how three different light intensities (1600, 4300, and 7200 lx) affect the biomass development, treatment of fuel synthesis wastewater and the recovery of valuable bioproducts between biofilm and suspended growth in a purple-bacteria enriched photobioreactor. Each condition was run in duplicate using an agricultural shade cloth as the biofilm support media in a continuously mixed batch reactor. The results showed that the highest chemical oxygen demand (COD) removal rate (56.8 ± 0.9 %) was found under the highest light intensity (7200 lx), which also led to the most biofilm formation and highest biofilm biomass production (1225 ± 95.7 mg). The maximum carotenoids (Crts) and bacteriochlorophylls (BChls) content occurred in the suspended growth of the 7200 lx reactor. BChls decreased with light intensity in suspended growth, while in biofilm both Crts and BChls were relatively stable between light conditions, likely due to an averaging effect as biofilm thickened at higher light intensity. Light intensity did not affect protein content of the biomass, however, biofilm showed a lower average (41.2 % to 43.7 %) than suspended biomass (45.4 % to 47.7 %). For polyhydroxybutyrate (PHB) the highest cell concentration in biofilm occurred at 1600 lx (11.4 ± 2.4 %), while for suspended growth it occurred at 7200 lx (22.7 ± 0.3 %), though total PHB productivity remained similar between reactors. Shading effects from the externally located biofilm could explain most variations in bioproduct distribution. Overall, these findings suggest that controlling light intensity can effectively influence the treatment of fuel synthesis wastewater and the recovery of valuable bioproducts in a biofilm photobioreactor.

Investigation of antibacterial and anticancer activities of biosynthesized metal-doped and undoped zinc oxide nanoparticles.

Over the past 10 years, nanotechnology has emerged as a very promising technique for a wide range of biomedical applications. Green synthesized metal and metal oxide nanoparticles (NPs) are cheap, easy to produce in large quantities, and safe for the environment. Currently, efforts are being made to dope ZnO in order to improve its optical, electrical, and ferromagnetic qualities as well as its crystallographic quality. Actually, doping is one of the simplest methods for enhancing an NP's physicochemical characteristics because it involves introducing impure ions into the crystal lattice of the particle. In this study, the biosynthesis of zinc oxide NPs (ZnONPs) and metal-doped (Mg2+ and Ag+) ZnONPs was carried out by using aqueous and water-alcoholic extracts of Cynara scolymus L. leaves, Carthamus tinctorius L. flowers, and Rheum ribes L. (RrL) plant, which are rich in phytochemical content. Plant extracts act as a natural reducing, capping, and stabilizing agent in the production. The produced NPs were characterized using a variety of methods, such as ultraviolet-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), and scanning electron microscopy (SEM). The produced metal-doped and undoped ZnONPs exhibited characteristic absorption peaks between 365 and 383nm due to their surface plasmon resonance bands. SEM analysis revealed that the NPs were oval, nearly spherical, and spherical. In the FTIR spectra, the Zn-O bonding peak ranges from 400 to 700cm-1. The peaks obtained in the range of 407-562cm-1 clearly represent the Zn-O bond. In addition, the FTIR results showed that there were notable amounts of phenol and flavonoid compounds in both the prepared extract and ZnONPs. According to DLS analysis results, the size distribution of produced NPs is between 120 and 786nm. The antibacterial properties of green produced NPs on Gram-positive (Staphylococcus aureus RN4220) and Gram-negative (Escherichia coli DH10B) bacterial strains were investigated by agar well diffusion method. In studies investigating the anticancer activities of biosynthesized NPs, mouse fibroblast cells (L929) were used as healthy cells and human cervical cancer cells (HeLa) were used as cancer cells. Only the produced Ag-ZnONPs showed potent dose-dependent antibacterial activity (at concentrations higher than 100µg/mL) against Gram-positive and Gram-negative bacteria. RrL-ZnONP-600 and RrL-ZnONP-800 NPs produced with water-ethanol extract of RrL plant and calcined at 600 and 800°C were effective at high concentrations in healthy cells and at low concentrations in HeLa cancer cells, showing that they have the potential to be anticancer agents. The study's findings highlight the potential of green synthesis techniques in the production of medicinal nanomaterials for the treatment of cancer and other biological uses.

Mucoadhesive mycophenolate mofetil and injectable platelet rich fibrin in the treatment of oral lichen planus

Abstract Background Oral Lichen Planus (OLP) is an inflammatory condition implicating T cell-mediated cytotoxicity, and involving oral mucosal surfaces. Mycophenolate mofetil (MMF) an immunosuppressive drug reversibly inhibits the proliferation of activated T cells. i-PRF contains a high concentration of growth factors (GF), cytokines, and regenerative cells that induce tissue regeneration and wound healing. Aim To evaluate the efficacy of topical application of mucoadhesive MMF and intra-lesional injection of platelet rich fibrin (i-PRF) in the treatment of symptomatic OLP. Patients and method 30 patients with symptomatic OLP were randomly assigned into three groups, each group included 10 patients. Group I: Were managed by bilateral intralesional injections with autologous i-PRF (Obtained by centrifugation of patient’s venous blood sample) weekly for 6 weeks. Group II: Were managed by topical MMF (Gel prepared by mycophenolate mofetil 2% obtained from BLD PHARM) gel twice daily for 6 weeks. Group III: Were managed by bilateral intralesional injections with triamcinolone acetonide (TA) (Epirelefan ampule ‘40 mg ⁄ 1 ml’. manufactured by: Egyptian international pharmaceutical industries co. (E.I.P.I.Co. factory2)) weekly for 6 weeks. Assessment was done clinically via calculating the changes in the lesion size, the severity of pain and burning sensation. Immunologically via measuring the amount of tumor necrosis factor-alpha (TNF-α) in saliva. Clinical parameters were recorded, at base line then every 2 weeks for 2 months, samples were collected and stored for immunologic test at baseline, 4 week and 8 week. Results For the three groups all clinical and immunological parameters showed significant improvement along the study periods. Regarding the intergroup comparison: At base line, no significant deference was observed between the three groups. The group comparison at the following measuring points of time showed that the clinical and immunological amelioration was in favor of the GI compared to the other two groups. Comparing GII and GIII the preference was in favor of GIII. Conclusion i-PRF can be considered as an effective and safe treatment remedies for OLP gives superior improvement clinically and immunologically compared to corticosteroids and MMF. Topical MMF gel can be used as treatment modality with reasonable efficacy.

The Role of Growth Differentiation Factor-15 in the Diagnosis of Patients with Chronic Angina Undergoing Coronary Angiography

Coronary artery disease (CAD) is considered the most prevalent leading cause of myocardial ischemia and mortality worldwide and can lead to angina pectoris and myocardial infarction (MI). Growth Differentiation Factor-15 (GDF-15) is usually measured together with other biomarkers to predict all-cause mortality. During stressful conditions associated with tissue injury and inflammation like myocardial ischemia, it is released into circulation and detected at high concentration in foam cells of the atherosclerotic plaque. Its circulating levels are associated with chronic diseases rather than acute diseases mainly cardiovascular diseases (CVDs) like CAD and chronic heart failure (CHF). The aim of the current study was to detect the role of GDF-15 as a new biomarker for the diagnosis of stable angina patients with normal left ventricular ejection fraction who were presented as having stable chest pain, so that to avoid endangering them to the invasive coronary angiography. Fasting venous blood samples were taken from 90 participants who were presented as having chest pain. They were all subjected to echocardiography, electrocardiography and coronary angiography. The left ventricular ejection fraction was calculated using the biplane M mode method. GDF-15 serum level was measured by using Human GDF-15 Sandwich ELISA Kit following the manufacturer’s instructions.The current study detected a high significant difference in the serum levels of GDF-15 and serum creatinine between the patients and the control group (P≤0.01). On the other hand, there were significant differences in the serum levels of triglycerides and VLDL-C between both study groups (P≤0.05). ROC curve analysis showed that GDF-15 had AUC= 1.00, the best cut off= 254.16 with sensitivity and specificity of 100%. So, it can be concluded that GDF-15 could be used as a biomarker for the diagnosis of stable angina patients with obstructive atherosclerotic plaque and normal LV ejection fraction.

Carrier-free nano-prodrugs for minimally invasive cancer therapy.

An anticancer nanodrug with few side effects that does not require the use of a nanocarrier, polyethylene glycol, or other additives has been developed. We have fabricated nano-prodrugs (NPDs) composed only of homodimeric prodrugs of the anticancer agent SN-38, which contains a disulfide bond. The prodrugs are stable against hydrolysis but selectively release SN-38 when the disulfide bond is cleaved by glutathione, which is present in high concentrations in cancer cells. The best-performing NPDs showed good dispersion stability in nanoparticle form, and animal experiments revealed that they possess much higher antitumor activity than irinotecan, a clinically applied prodrug of SN-38. This performance was achieved by improving tumor accumulation due to the size effect and targeted drug release mechanism. The present study provides an insight into the development of non-invasive NPDs with high pharmacological activity, and also offers new possibilities for designing prodrug molecules that can release drugs in response to various kinds of triggers.

Forward osmosis zwitterionic membranes for platelet concentration – Evaluation of the feasibility of the concept

This study focuses on the development of forward osmosis (FO) membranes tailored for platelet and growth factor enrichment applications while maintaining minimal activation throughout the process. The FO membrane structure comprises a polyacrylonitrile (PAN) layer, fabricated using vapor-induced phase separation (VIPS), atop a polyethylene terephthalate (PET) substrate. Then, a polyamide (PA) layer was formed through interfacial polymerization (IP) at the PAN layer interface. The PET side of the membrane was further enhanced with coatings of antifouling copolymers, based on poly(ethylene glycol) methyl ether methacrylate (PEGMA) alone or both PEGMA and zwitterionic sulfobetaine methacrylate (SBMA). In a first step, the formation of each layer was optimized. The structure of the PAN layer was adjusted through the polymer concentration (15 wt%) and the exposure time to vapors (15 min) during the VIPS step. The PA layer was optimized by adjusting the curing temperature to 70 °C. The antifouling copolymer was selected by conducting protein adsorption tests. Subsequently, these tailored FO membranes were employed in the enrichment of plasma proteins, growth factors, and platelets from platelet-rich plasma. It is shown that the membrane modified with a copolymer made of butyl methacrylate (BMA), PEGMA and SBMA, referred to as poly(BMA-r-PEGMA-r-SBMA), enabled to reach a Human Serum Albumin concentration factor of 1.32 and a platelet concentration using PRP of 2.4. Despite partial platelet activation (12 %) due to the high cell concentration, the platelet content is much higher than in PRP or whole blood, which could benefit platelet-based therapies. In addition, the system can be applied to the concentration of growth factors, with PDGF and VEGF concentration factors of 1.92 and 2.58, respectively, which could contribute to the advancement of regenerative medicine.

Fishmeal-Based Media Supports Growth and Endospore Production of Locally-Isolated Lysinnibacillus sphaericus and Induces its Toxicity to 3rd Instar Aedes aegypti Larvae in Laboratory Conditions

The aim of this study was to determine whether fishmeal-based media could be used to grow L. sphaericus and induce its toxicity against Aedes aegypti larvae. Three concentrations (10, 20 and 30%) of fishmeal-based media were used to grow L. sphaericus isolate Bs2-1-2. Cell growth and endospore production were observed every 12 hours for 72 hours. The lethal concentration was measured every 24 hours for 72 hours of fermentation. The highest cell concentration was found in L. sphaericus grown on the media with 30% fishmeal concentration (3.03x1008 cells/mL), followed by 20% concentration (2.43x1008 cells/mL) and the lowest at 10% concentration (2.20x1008 cells/mL). At the end of fermentation, the highest concentration was found in L. sphaericus grown on 30% fishmeal-based media (1.51x1008 cells/mL), followed by 20% media (6.95x1007 cells/mL) and 10% media (3.21x1007 cells/mL). After 72-hour incubation, the highest endospore concentration was achieved by L. sphaericus grown on 20% (2.51x1008 cells/mL) and 10% (2.19x1008 cells/mL) fishmeal-based media. Initial larval toxicity of L. sphaericus showed the highest mortality on 20 and 30% fishmeal-based media (both reaching 53.33%), while 10% fishmeal-based media gave only 26.67% larval mortality. The LC50 value at 72 hours was achieved by L. sphaericus cultured on 30% fishmeal-based media (2.47 x 1008 cells/mL), followed by 20% concentration (4.82 x 1008 cells/mL) and 10% concentration (9.01 x 1009 cells/mL). The conclusion of this study was all concentrations of fishmeal-based media could support cell growth, endospore production and larval toxicity induction of L. sphaericus.

Intra-lymph node crosslinking of antigen-bearing polymers enhances humoral immunity and dendritic cell activation.

Lymph node (LN)-resident dendritic cells (DCs) are a promising target for vaccination given their professional antigen-presenting capabilities and proximity to a high concentration of immune cells. Direct intra-LN injection has been shown to greatly enhance the immune response to vaccine antigens compared to traditional intramuscular injection, but it is infeasible to implement clinically in a vaccination campaign context. Employing the passive lymphatic flow of antigens to target LNs has been shown to increase total antigen uptake by DCs more than inflammatory adjuvants, which recruit peripheral DCs. Herein, we describe a novel vaccination platform in which two complementary multi-arm poly(ethylene glycol) (PEG) polymers-one covalently bound to the model antigen ovalbumin (OVA)-are injected subcutaneously into two distinct sites. These materials then drain to the same LN through different lymphatic vessels and, upon meeting in the LN, rapidly crosslink. This system improves OVA delivery to, and residence time within, the draining LN compared to all control groups. The crosslinking of the two PEG components also improves humoral immunity without the need for any pathogen-mimicking adjuvants. Further, we observed a significant increase in non-B/T lymphocytes in LNs cross-presenting the OVA peptide SIINFEKL on MHC I over a dose-matched control containing alum, the most common clinical adjuvant, as well as an increase in DC activation in the LN. These data suggest that this platform can be used to deliver antigens to LN-resident immune cells to produce a stronger humoral and cellular immune response over materials-matched controls without the use of traditional adjuvants.

Analysis of Amphora ostrearia var. minor Grunow, a blooming marine diatom (Bacillariophyceae) in French Atlantic coastal waters and its transfer to the genus Tetramphora

A marine amphoroid diatom, responsible for blooms in 2011 and 2019 in French Atlantic waters was studied using morphology and molecular phylogeny. The highest cell concentrations were reached in the region of Marennes Oléron on 19 August 2011 and were related to a greyish discolouration of gills of oysters and mussels. It was identified as Amphora ostrearia var. minor Grunow, based on morphological characteristics. To ensure the correct identification, type material was re-investigated, using the type slide n° 142 (Cleve & Möller 1878. Diatoms. Part II. Esatas Edquists Boktryckeri, Upsala: 49–108) that enabled us to establish the identity of the taxon. Plastid morphology corresponded to Mereschkowsky’s type 8 amphoroid chloroplast, a feature typical for the genus Tetramphora Mereschkowsky. Results of a phylogenetic analysis inferred from a concatenated alignment including the nuclear marker SSU and the chloroplast rbcL indicated that A. ostrearia var. minor was positioned inside the monophyletic clade Tetramphora (Mereschkowsky) Stepanek & Kociolek. This, together with the morphological data, necessitated a transfer of A. ostrearia var. minor Grunow to the genus Tetramphora (Mereschkowsky) Stepanek & Kociolek. In addition, the genetic distances (p-values) from SSU–rbcL sequences were estimated among the species of Tetramphora including T. ostrearia, the generitype. These revealed that the divergence between Tetramphora ostrearia (Brébisson) Mereschkowsky and its variety minor was higher than the mean value within species of the genus. As a consequence, the studied taxon is raised to the species level as Tetramphora minor (Grunow) Nézan, comb. et stat. nov. Toxin analysis of four strains of T. minor revealed the absence of domoic acid production. Pigment analysis of T. ostrearia revealed a high fucoxanthin production, similar to other amphoroid species.

PH-Responsive β-Glucans-Complexed mRNA in LNPs as an Oral Vaccine for Enhancing Cancer Immunotherapy.

mRNA vaccines for cancer immunotherapy are commonly delivered using lipid nanoparticles (LNPs), which, when administered intravenously, may accumulate in the liver, potentially limiting their therapeutic efficacy. To overcome this challenge, the study introduces an oral mRNA vaccine formulation tailored for efficient uptake by immune cells in the gastrointestinal (GI) tract, known for its high concentration of immune cells, including dendritic cells (DCs). This formulation comprises mRNA complexed with β-glucans (βGlus), a potential adjuvant for vaccines, encapsulated within LNPs (βGlus/mRNA@LNPs). The βGlus/mRNA complexes within the small compartments of LNPs demonstrate a distinctive ability to partially dissociate and reassociate, responding to pH changes, effectively shielding mRNA from degradation in the harsh GI environment. Upon oral administration to tumor-bearing mice, βGlus/mRNA@LNPs are effectively taken up by intestinal DCs and local nonimmune cells, bypassing potential liver accumulation. This initiates antigen-specific immune responses through successful mRNA translation, followed by drainage into the mesenteric lymph nodes to stimulate T cells and trigger specific adaptive immune responses, ultimately enhancing antitumor effects. Importantly, the vaccine demonstrates safety, with no significant inflammatory reactions observed. In conclusion, the potential of oral βGlus/mRNA@LNPs delivery presents a promising avenue in cancer immunotherapy, offering needle-free and user-friendly administration for widespread adoption and self-administration.

Exploring operational boundaries for acoustic concentration of cell suspensions

The development of a standardized, generic method for concentrating suspensions in continuous flow is challenging. In this study, we developed and tested a device capable of concentrating suspensions with an already high cell concentration to meet diverse industrial requirements. To address typical multitasking needs, we concentrated suspensions with high solid content under a variety of conditions. Cells from Saccharomyces cerevisiae, Escherichia coli, and Chinese hamster ovary cells were effectively focused in the center of the main channel of a microfluidic device using acoustophoresis. The main channel bifurcates into three outlets, allowing cells to exit through the central outlet, while the liquid evenly exits through all outlets. Consequently, the treatment separates cells from two-thirds of the surrounding liquid. We investigated the complex interactions between parameters. Increasing the channel depth results in a decrease in process efficiency, attributed to a decline in acoustic energy density. The study also revealed that different cell strains exhibit distinct acoustic contrast factors, originating from differences in dimensions, compressibility, and density values. Finally, a combination of high solid content and flow rate leads to an increase in diffusion through a phenomenon known as shear-induced diffusion.Key points• Acoustic focusing in a microchannel was used to concentrate cell suspensions• The parameters influencing focusing at high concentrations were studied• Three different cell strains were successfully concentratedGraphical abstract

Assessment of the digestibility, growth performance, hematological and serum biochemical profile of Bandjock Local Pigs (BLP) and Duroc X Large White pigs (DLW)

The study aimed to assess the digestibility, growth performance, and selected biochemical and hematological parameters of Bandjock Local pigs (BLP) and Duroc X Large White pigs (DLW). We hypothesize that the use of local ingredients in diet formulation associated to improved rearing conditions, enhance the growth performance, digestibility, biochemical and hematological parameters of BLP. The trial involved dividing twenty-four eight-week-old weaner pigs into two groups. Each group was randomly assigned to separate pig units. Animal management and feeding were consistent between both groups. The trial lasted for 120 days during which the growth performance, the digestibility of ingested nutrients, and biochemical and hematological parameters were evaluated. The results indicate that DLW pigs registered a weight gain (46.56±5.19 kg) significantly higher than BLP pigs (34.02), with a statistically similar feed conversion ratio. Except for albumin which was significantly higher in DLW and urea in BLP, there were no significant differences (p > 0.05) in total protein, cholesterol, globulin, triglycerides, creatinine, AST, and ALT as well as hematological parameters between the breeds. However, the exotic DLW had a relatively high mean blood platelets and white blood cell concentration. Although the fecal nitrogen was higher in BLP and the urinary nitrogen was lower in the DLW, there were significant differences (p < 0.05) for urine, fecal, and total excreted nitrogen in both breeds. The lowest scores in nutrient digestibility were recorded with BLP compared to DWL, except for crude fibers. The results of this study demonstrated that using diet formulated with local ingredients and improved rearing conditions, Cameroonian local indigenous pigs have a better productivity compared to exotic breeds. It suggests that efforts should be made by authorities to promote and valorize the rearing of indigenous pigs in complement to exotic pig breeds in view of strengthening the Cameroonian pig industry.

A new species of Australotaenia (Cestoda: Proteocephalidae) from a hylid frog in Australia.

A new species of the little-known genus Australotaenia de Chambrier & de Chambrier, 2010 is described from Ranoidea australis (Gray) (Anura: Hylidae), commonly known as the giant frog, northern snapping frog or round frog and which is a burrowing frog species native to Australia. Australotaenia hobbsi n. sp. is the fourth species of the genus, but the first taxon found in a burrowing frog and in northern Australia. The other species were found in Australian tree frogs (Litoria spp.) in southwestern and southeastern Australia, and in the homalopsid snake Enhydris enhydris (Schneider) in Cambodia. Australotaenia hobbsi n. sp. differs from its congeners (i) by the wider strobila (maximum body width 1,750 µm versus < 930 µm), scolex (570 µm versus < 390 µm) and suckers (diameter 215-230 µm versus < 140 µm); (ii) by the smaller relative size of the cirrus sac (12-15% of proglottid width versus 17-33%); (iii) by the absence of a vaginal sphincter (present in the other three species); (iv) different arrangement of the inner longitudinal musculature, which consists of a few individual muscle fibres (in contrast to the fibres grouped in bundles in other species). Australotaenia species and Pangasiocestus romani Scholz & de Chambrier, 2012 from the spot pangasius Pangasius lernaudii Boucourt, both of the subfamily Acanthotaeniinae, are unique among proteocephalids in terms of intermediate uterine development, with a high concentration of chromophilic cells around the tip of the lateral uterine diverticula.