Suspension Cell Lines Research Articles

A Sample Preparation Protocol for High Throughput Immunofluorescence of Suspension Cells on an Adherent Surface.

Imaging is a powerful approach for studying protein expression and has the advantage over other methodologies in providing spatial information in situ at single cell level. Using immunofluorescence and confocal microscopy, detailed information of subcellular distribution of proteins can be obtained. While adherent cells of different tissue origin are relatively easy to prepare for imaging applications, non-adherent cells from hematopoietic origin, present a challenge due to their poor attachment to surfaces and subsequent loss of a substantial fraction of the cells. Still, these cell types represent an important part of the human proteome and express genes that are not expressed in adherent cell types. In the era of cell mapping efforts, overcoming the challenge with suspension cells for imaging applications would enable systematic profiling of hematopoietic cells. In this work, we successfully established an immunofluorescence protocol for preparation of suspension cell lines, peripheral blood mononucleated cells (PBMC) and human platelets on an adherent surface. The protocol is based on a multi-well plate format with automated sample preparation, allowing for robust high throughput imaging applications. In combination with confocal microscopy, the protocol enables systematic exploration of protein localization to all major subcellular structures.

Gene expression variability between randomly and targeted transgene integration events in tobacco suspension cell lines

Genome editing tools such as zinc-finger nucleases provide novel strategies for genetic manipulation in plants. Unlike agrobacterium-mediated or direct gene transfer, which introduce genes randomly into the genome and thereby potentially resulting in high variation of gene expression, the targeted gene addition provides predictable integration of DNA sequences into a specified location of the plant genome. We investigated whether various independent cell lines that all contain a transgene placed in the same genomic locus by zinc-finger nuclease-mediated homologous recombination (HR) would yield a more reproducible and homogeneous level of expression compared to integration events generated via agrobacterium-mediated transformation at random sites. The variance of gene expression of targeted HR events and random integration events was analyzed in Nicotiana tabacum L cv. Bright Yellow 2 (BY-2) suspension cells by measuring protein amount produced from the transgene by flow cytometry, thus providing the first report on positional effects of marker gene expression in a quickly proliferating plant suspension cell line. Marker protein levels of targeted HR and single-copy random events covered a similar range; however, the uniformity of protein expression in a given cell line was significantly higher in targeted events than in lines with randomly inserted transgene; the same is true for the overall viability of protoplasts from HR lines. In conclusion, using targeted insertion into a qualified locus of a well-characterized line leads to more reliable results than random insertion into the genome.

Exploring potential FDA-approved components for DMSO-free T-cell cryopreservation solutions

Background & Aim The cryopreservation process is an integral part of cellular therapies. However, current DMSO-containing cryomedia are toxic and cause many cyto- and genotoxic such as causing stress at the membrane interface, oxidizing free thiol groups on proteins, and alters the epigenetic DNA methylation profile etc. These has prompted an urgent need for the development of a non-toxic, DMSO-free cryomedia. Our goal is to develop DMSO-free cryomedia with similar or superior cell preservation capacity and post-thaw viability than the leading DMSO-containing cryomedia currently use. We explored the cryoprotectant capabilities and other parameters regarding prevention of cryo-damage of components including anti-apoptosis molecules, antioxidants, and molecules related to cell proliferation. These components offer various functionalities by working against intra- and extracellular ice formation as well as against cell damage during post-thaw recovery. All components are approved by the FDA and under regulatory compliance. Aim:The current T-cell capacity for CAR-T DMSO cryomedia is over 3 × 106 cells per mL of cryomedia; our objective goal is to develop a solution that will successfully preserve 5 × 106 cells per mL Methods, Results & Conclusion Methods: We used Jurkat T-cells, an immortalized human suspension cell line, as the initial model system during cryomedia optimization. During the optimization process, we compared the cryopreservation performance of our DMSO-free cryomedia to DMSO-containing cryomedia using Jurkat T-cells. The tested cryomedia components were rapidly screened by evaluating initial post-thaw viability; when the post-thaw viability was higher than 70%, they were further evaluated after a 72-hour recovery period to ensure cell viability and proliferation were not impacted by the cryomedia. Results Many promising candidates were observed based on the relative post-thaw viability and performance on recovery viability. Finally, we evaluate the potential candidates using PBMC-derived T-cells to verify the success of the final cryomedia We found T cell can preserve > 90% superior than traditional DMSO cryopreservation solution at great post-thaw viability.. Conclusion This study exhibits an accelerated cryomedia screening system which has the potential to be a valuable paradigm in future development of cellular therapeutic products as it can be applied to many cell types and cell therapies including CAR-T, CAR-NK etc.

Orbitally Shaken Single-Use Bioreactor for Animal Cell Cultivation: Fed-Batch and Perfusion Mode.

Increasing the cultivation volume from small to large scale can be a rather complex and challenging process when the method of aeration and mixing is different between scales. Orbitally shaken bioreactors (OSBs) utilize the same hydrodynamic principles that define the success of smaller-scale cultures, which are developed on an orbitally shaken platform, and can simplify scale-up. Here we describe the basic working principles of scale-up in terms of the volumetric oxygen transfer coefficient (kLa) and mixing time and how to define these parameters experimentally. The scale-up process from an Erlenmeyer flask shaken on an orbital platform to an orbitally shaken single-use bioreactor (SB10-X, 12 L) is described in terms of both fed-batch and perfusion-based processes. The fed-batch process utilizes a recombinant variant of the mammalian cell line, Chinese hamster ovary (CHO), to express a biosimilar of a therapeutic monoclonal antibody. The perfusion-based process utilizes either an alternating tangential flow filtration (ATF) or a tangential flow filtration (TFF) system for cell retention to cultivate an avian cell line, AGE1.CR.pIX, for the propagation of influenza A virus, H1N1, in high cell density. Based on two example cell cultivations, processes outline the advantages that come with using an orbitally shaken bioreactor for scaling-up a process. The described methods are also applicable to other suspension cell lines.

Perfusion Control for High Cell Density Cultivation and Viral Vaccine Production.

The global demand for complex biopharmaceuticals like recombinant proteins, vaccines, or viral vectors is steadily rising. To further improve process productivity and to reduce production costs, process intensification can contribute significantly. The design and optimization of perfusion processes toward very high cell densities require careful selection of strategies for optimal perfusion rate control. In this chapter, various options are discussed to guarantee high cell-specific virus yields and to achieve virus concentrations up to 1010 virions/mL. This includes reactor volume exchange regimes and perfusion rate control based on process variables such as cell concentration and metabolite or by-product concentration. Strategies to achieve high cell densities by perfusion rate control and their experimental implementation are described in detail for pseudo-perfusion or small-scale perfusion bioreactor systems. Suspension cell lines such as MDCK, BHK-21, EB66®, and AGE1.CR.pIX® are used to exemplify production of influenza, yellow fever, Zika, and modified vaccinia Ankara virus.

Design, Optimization, and Adaptive Control of Cell Culture Seed Trains.

For the production of biopharmaceuticals, a procedure called seed train or inoculum train is required to generate an adequate number of cells for the inoculation of the production bioreactor. This seed train is time- and cost-intensive but offers potential for optimization. A method and a protocol are described for seed train mapping, directed modeling, and simulation as well as its optimization regarding selected optimization criteria such as optimal points in time for cell passaging. Furthermore, the method can also be applied for the transfer of a seed train to a different production plant or the design of a new seed train, for example, for a new cell line. Another application is to support the selection of the optimal clone for a new process. Seed train prediction can be performed for different clones, and so it can be analyzed how the seed train protocol would look like and for which clones a suitable seed train protocol could be found.Although the chapter is directed toward suspension cell lines, the method is also generally applicable, e.g., for adherent cell lines.

How to Produce mAbs in a Cube-Shaped Stirred Single-Use Bioreactor at 200 L Scale.

Single-use bioreactors have increasingly been used in recent years, for both research and development as well as industrial production, especially in mammalian cell-based processes. Among the numerous single-use bioreactors available today, wave-mixed bags and stirred systems dominate. Wave-mixed single-use bioreactors are the system of choice for inoculum production, while stirred single-use bioreactors are most often preferred for antibody expression. For this reason, the present chapter describes protocols instructing the reader to use the wave-mixed BIOSTAT® RM 50 for cell expansion and to produce a monoclonal antibody (mAb) in Pall's Allegro™ STR 200 at pilot scale for the first time. All methods described are based on a Chinese hamster ovary (CHO) suspension cell line expressing a recombinant immunoglobulin G (IgG).

Producing the sulfur-containing metabolite asparaptine in Asparagus calluses and a suspension cell line.

Asparaptine, a conjugate of L-arginine and asparagusic acid, was found in green asparagus (Asparagus officinalis) using ultrahigh-resolution metabolomics for sulfur-containing metabolites (S-metabolites), called S-omics. Asparaptine has been shown to inhibit the activity of angiotensin-converting enzyme. Larger amounts of this S-metabolite are therefore required for further analysis; however, there are limitations that asparagus is a perennial plant and its spears, wherein asparaptine accumulates, can be mainly harvested at the spring to summer season. In order to overcome these, we prepared a callus and suspension cell line from green asparagus. Untargeted metabolome analysis using liquid chromatography-tandem mass spectrometry was performed in the materials as well as spears and three calluses derived from wild type Asparagus. The analysis demonstrated that the amount of asparaptine in the callus derived from the green asparagus was more than the others per mg dry weight. The suspension cell line treated with methyljasmonate showed the induction of asparaptine, suggesting that the asparaptine production is modifiable under appropriate culture conditions. The described materials can be utilized for the production of asparaptine and in integrated metabolomics to study the biosynthesis of this S-metabolite, which is currently unknown.

A Versatile Polymer‐Based Platform for Intracellular Delivery of Macromolecules

AbstractThe plasma membrane barrier greatly restricts intracellular delivery of macromolecules. Currently available methods suffer from various limitations, including low delivery efficiency, high cytotoxicity, or incompatibility with a wider range of macromolecules or cell types. To overcome these issues, stimuli‐responsive polymers such as the bio‐inspired, pH‐responsive poly(l‐lysine isophthalamide) grafted with l‐phenylalanine at a stoichiometric ratio of 50% (PP50) can be used. In mildly acidic environments, the pseudopeptidic polymer can permeabilize the plasma membrane overcoming the problem of payload entrapment in the endosomes and allowing for efficient intracellular delivery. It is demonstrated that PP50 is capable of intracellular delivery by simple co‐incubation at pH 6.5 with various macromolecules, including different‐sized Dextrans, green fluorescent protein (GFP), and an apoptotic peptide. The delivery process is fast, nontoxic, and compatible with multiple cell types, including adherent and suspension cell lines, primary human mesenchymal stem cells, and cells grown as spheroids. In addition, apoptotic peptide delivery by co‐incubation with PP50 is over three times more effective than delivery using other common methods, including poly(ethyleneimine) (PEI), cell penetrating peptides (CPPs), and electroporation. The findings suggest that payload delivery by co‐incubation with PP50 is a flexible, controllable method allowing delivery of various payloads to many different cell types in vitro.

A Deleted Deletion Site in a New Vector Strain and Exceptional Genomic Stability of Plaque-Purified Modified Vaccinia Ankara (MVA)

Vectored vaccines based on highly attenuated modified vaccinia Ankara (MVA) are reported to be immunogenic, tolerant to pre-existing immunity, and able to accommodate and stably maintain very large transgenes. MVA is usually produced on primary chicken embryo fibroblasts, but production processes based on continuous cell lines emerge as increasingly robust and cost-effective alternatives. An isolate of a hitherto undescribed genotype was recovered by passage of a non-plaque-purified preparation of MVA in a continuous anatine suspension cell line (CR.pIX) in chemically defined medium. The novel isolate (MVA-CR19) replicated to higher infectious titers in the extracellular volume of suspension cultures and induced fewer syncytia in adherent cultures. We now extend previous studies with the investigation of the point mutations in structural genes of MVA-CR19 and describe an additional point mutation in a regulatory gene. We furthermore map and discuss an extensive rearrangement of the left telomer of MVA-CR19 that appears to have occurred by duplication of the right telomer. This event caused deletions and duplications of genes that may modulate immunologic properties of MVA-CR19 as a vaccine vector. Our characterizations also highlight the exceptional genetic stability of plaque-purified MVA: although the phenotype of MVA-CR19 appears to be advantageous for replication, we found that all genetic markers that differentiate wildtype and MVA-CR19 are stably maintained in passages of recombinant viruses based on either wildtype or MVA-CR.

Combined EZH2 and BCL2 Inhibitors As Precision Therapy for Genetically Defined DLBCL Subtypes

DLCBL has recently been classified into genetically defined subtypes based on groupings of particular genetic lesions (Chapuy et al, Nat Med 2018; Schmitz et al, NEJM 2018). One predominant cluster, C3 or EZB, is defined by mutations in the chromatin modifying genes EZH2, KMT2D, and CREBBP as well as alterations in BCL2 including mutations and/or translocation of BCL2 to the IgH enhancer. Since tumors in this cluster are likely dependent on both EZH2 and BCL2, and these oncogenes carry out their effects through distinct mechanisms and pathways, targeting both of these oncogenes is a rational therapeutic approach. We hypothesized that EZH2 inhibition and BCL2 inhibition would be synergistic in DLBCL with characteristics of the C3/EZB cluster. To test this, we evaluated the EZH2 inhibitor tazemetostat and the BCL2 inhibitor venetoclax in DLBCL cells, 3D lymphoma organoids, and patient derived xenografts. To assess the effect of combination therapy with tazemetostat and venetoclax, we administered each drug alone and the combination in a panel of DLBCL cell lines, including cells with and without EZH2 mutation and BCL2 translocation. In DLBCL cells with both a BCL2 translocation and EZH2 mutation, the combination resulted in increased killing compared to either drug alone (Figure 1, SUDHL6 (p<0.005), WSU-DLCL2 (p<0.005), and OCI-LY1 (p<0.005)). In contrast, in cells with WT EZH2 and no BLC2 translocation, the effect of the combination was not different than either drug alone. To evaluate for synergy, cells were exposed to increasing doses of each drug alone and the combination. The combined response was evaluated using the Chou-Talalay method. Synergy between tazemetostat and venetoclax was observed in SUDLH-6 (CI value 0.03), WSU-DLCL2 (CI 0.26) and OCI-LY1 (CI 0.06) but not in Farage and LY7 both of which have WT EZH2 and no BCL2 translocation. Since cell lines in suspension do not reflect lymph node architecture, we developed a 3D lymphoma "organoid" culture system that consists of extracellular matrix, lymphoma cells, and stromal cells (Tian et al, Biomaterials 2015; Beguelin et al, Nat Commun 2017). GCB-DLBCLs express integrin αvβ3 that may bind to RGD peptides or vitronectin in tumor extracellular matrix. Based on this, we developed matrix metalloproteinase (MMP)-degradable 3D lymphoma hydrogels functionalized with RGD peptides. To generate organoids, we homogeneously encapsulated DLBCL cells (40,000/gel) in 10 µL hydrogel droplets fabricated in individual wells of a 96-well plate. We established two organoid systems to evaluate response to tazemetostat/venetoclax combination therapy: 1) OCI-LY1 organoids; 2) patient derived xenograft (PDX) organoids. The PDX organoids were generated from a patient tumor after propagation in NSG mice. The PDX tumor harbors both a BCL2 translocation and EZH2 mutation. Organoid viability was evaluated using immunofluorescence for calcein AM (live cells) and ethidium homodimer (dead cells) as well as flow cytometry. In both OCI-Ly1 organoids and PDX organoids, tazemetostat and venetoclax had minimal activity as single agents, however the combination resulted in significant cell killing (Figure 2). To investigate potential mechanisms of synergy, we evaluated RNA-seq profiles of a panel of DLBCL cell lines (n=26) treated with vehicle vs. EZH2 inhibitor (Brach et al, Mol Cancer Ther 2017). Preliminary data suggest that EZH2 inhibition induces expression of pro-apoptotic proteins genes including BCL2L11 (Wilcoxon p=0.01), BAD (p=0.02), BMF (p<0.01), BCL2L13 (p=0.02), and BCL2L14 (p<0.01). BCL2 inhibition with venetoclax may be further enhancing pro-apoptotic signals and lymphoma cell death, especially in C3/EZB DLBCL tumors with dependence on BCL2. In summary, using novel model systems, we have demonstrated that BCL2 inhibition combined with EZH2 inhibition results in synergistic anti-tumor effect that is anticipated to be especially effective as precision therapy for the newly identified cluster 3/EZB DLBCL subtype. A clinical trial of this combination is currently in development. Disclosures Melnick: Janssen: Research Funding; Constellation: Consultancy; Epizyme: Consultancy. Roth:Janssen: Consultancy; ADC Therapuetics: Consultancy; Merck: Membership on an entity's Board of Directors or advisory committees.

Advanced Establishment of Stable Recombinant Human Suspension Cell Lines Using Genotype-Phenotype Coupling Transposon Vectors.

Stable mammalian, namely human, suspension cell lines play a pivotal role in red biotechnology production scenarios for the generation of state-of-the-art biologics. However, selection of genetically modified and highly productive cell populations-prior to the establishment of clonal lines-is often challenging. To overcome this limitation, we first describe an optimized transient transfection protocol using the inexpensive reagent polyethylenimine (PEI) and human 293F cells. Transposon donor vectors derived from Sleeping Beauty encompassing a cassette with the reporter gene encoding for the green fluorescent protein (GFP) coupled with an internal ribosome entry site (IRES) to the expression of puromycin-resistance are employed to readily detect transfected cells. Upon stable transfection in the presence and absence of transposase expression, respectively,and subsequent antibiotic selection, GFP expression using flow cytometry analysis, cell viability, and cell density can be examined over a range of up to 3 weeks. Owing to the integration of high vectorcopy numbers into the target cell genome, transposase-mediated transposition of transposon donor vectors is instrumental in the faster establishment of recombinant cell population as compared to the classical stable transfection of plasmid DNA.

CRISPR/Cas9-mediated gfp gene inactivation in Arabidopsis suspension cells.

Targeted genome editing using CRISPR/Cas9 is a promising technology successfully verified in various plant species; however, it has hardly been used in plant cell suspension cultures. Here, we describe a successful knockout of a green fluorescent protein (gfp) reporter gene in Arabidopsis cell culture. We transformed seven transgenic suspension cell lines carrying one to three gfp gene copies with a binary vector containing genes coding for Cas9 and guide RNAs targeting the gfp gene. We detected the site-specific mutations by restriction analysis of a gfp amplicon. DNA sequencing of the PCR products confirmed high diversity of insertion-deletion mutations in the cell lines after the editing. We also analyzed gfp mRNA expression by real-time PCR and observed a decrease in gfp transcription after the target site modification. We can conclude that the CRISPR/Cas9 system can be successfully used for introducing site-specific mutations into the genome of cultured suspension cells of Arabidopsis.

Physical events occurring during the cryopreservation of immortalized human T cells.

Cryopreservation is key for delivery of cellular therapies, however the key physical and biological events during cryopreservation are poorly understood. This study explored the entire cooling range, from membrane phase transitions above 0°C to the extracellular glass transition at -123°C, including an endothermic event occurring at -47°C that we attributed to the glass transition of the intracellular compartment. An immortalised, human suspension cell line (Jurkat) was studied, using the cryoprotectant dimethyl sulfoxide. Fourier transform infrared spectroscopy was used to determine membrane phase transitions and differential scanning calorimetry to analyse glass transition events. Jurkat cells were exposed to controlled cooling followed by rapid, uncontrolled cooling to examine biological implications of the events, with post-thaw viable cell number and functionality assessed up to 72 h post-thaw. The intracellular glass transition observed at -47°C corresponded to a sharp discontinuity in biological recovery following rapid cooling. No other physical events were seen which could be related to post-thaw viability or performance significantly. Controlled cooling to at least -47°C during the cryopreservation of Jurkat cells, in the presence of dimethyl sulfoxide, will ensure an optimal post-thaw viability. Below -47°C, rapid cooling can be used. This provides an enhanced physical and biological understanding of the key events during cryopreservation and should accelerate the development of optimised cryobiological cooling protocols.

Efficient influenza A virus production in high cell density using the novel porcine suspension cell line PBG.PK2.1

Seasonal and pandemic influenza respiratory infections are still a major public health issue. Vaccination is the most efficient way to prevent influenza infection. One option to produce influenza vaccines is cell-culture based virus propagation. Different host cell lines, such as MDCK, Vero, AGE1.CR or PER.C6 cells have been shown to be a good substrate for influenza virus production. With respect to the ease of scale-up, suspension cells should be preferred over adherent cells. Ideally, they should replicate different influenza virus strains with high cell-specific yields. Evaluation of new cell lines and further development of processes is of considerable interest, as this increases the number of options regarding the design of manufacturing processes, flexibility of vaccine production and efficiency.Here, PBG.PK2.1, a new mammalian cell line that was developed by ProBioGen AG (Germany) for virus production is presented. The cells derived from immortal porcine kidney cells were previously adapted to growth in suspension in a chemically-defined medium. Influenza virus production was improved after virus adaptation to PBG.PK2.1 cells and optimization of infection conditions, namely multiplicity of infection and trypsin concentration. Hemagglutinin titers up to 3.24 log10(HA units/100 µL) were obtained in fed-batch mode in bioreactors (700 mL working volume). Evaluation of virus propagation in high cell density culture using a hollow-fiber based system (ATF2) demonstrated promising performance: Cell concentrations of up to 50 × 106 cells/mL with viabilities exceeding 95%, and a maximum HA titer of 3.93 log10(HA units/100 µL). Analysis of glycosylation of the viral HA antigen expressed showed clear differences compared to HA produced in MDCK or Vero cell lines. With an average cell-specific productivity of 5000 virions/cell, we believe that PBG.PK2.1 cells are a very promising candidate to be considered for next-generation influenza virus vaccine production.

Multiplexed profiling of RNA and protein expression signatures in individual cells using flow or mass cytometry.

Advances in single-cell analysis technologies are providing novel insights into phenotypic and functional heterogeneity within seemingly identical cell populations. RNA within single cells can be analyzed using unbiased sequencing protocols or through more targeted approaches using in situ hybridization (ISH). The proximity ligation assay for RNA (PLAYR) approach is a sensitive and high-throughput technique that relies on in situ and proximal ligation to measure at least 27 specific RNAs by flow or mass cytometry. We provide detailed instructions for combining this technique with antibody-based detection of surface/internal protein, allowing simultaneous highly multiplexed profiling of RNA and protein expression at single-cell resolution. PLAYR overcomes limitations on multiplexing seen in previous branching DNA-based RNA detection techniques by integration of a transcript-specific oligonucleotide sequence within a rolling-circle amplification (RCA). This unique transcript-associated sequence can then be detected by heavy metal (for mass cytometry)- or fluorophore (for flow cytometry)-conjugated complementary detection oligonucleotides. Included in this protocol is methodology to label oligonucleotides with lanthanide metals for use in mass cytometry. When analyzed by mass cytometry, up to 40 variables (with scope for future expansion) can be measured simultaneously. We used the described protocol to demonstrate intraclonal heterogeneity within primary cells from chronic lymphocytic leukemia patients, but it can be adapted to other primary cells or cell lines in suspension. This robust, reliable and reproducible protocol can be completed in 2-3 d and can be paused at several stages for convenience.

STUDY OF DNA TRANSFORMATION DYNAMICS IN ВНК-21/2-17 CELL CULTURE USING FLOW CYTOMETRY DURING FMD VIRUS REPRODUCTION

The research tasks covered the study of ВНК-21/2-17 cell DNA transformation dynamics during FMDV reproduction process. It was noted that the destruction of major cell population coincided with the increase in apoptotic cell number and detritus amount. Three hours post cell culture infection increase in apoptosis and detritus was observed, G 1-phase decreased by 17–21% and polynuclear cells grew by 2.3 times. In seven hours, the drastic rise in cell death was noted. It was established that at all stages of FMDV culture in ВНК-21/2-17 suspension cell line, diploid cells G1(2n) were predominant, being basic cells for the virus reproduction. Cells in synthetic (S) and G2and M-phases were less susceptible to virus. Using flow cytometry technique made it possible to quantify cell cycle phases during reproduction in FMDV cells. We also succeeded in comparing between these phases, virus livability and virus reproduction dynamics. The study of FMDV cytopathic effect in ВНК-21/2-17 cells demonstrated that one of the optimization trends in culture vaccine production include proliferation inhibitory factor use at a certain cell cycle phase.

Получение и характеристика культур клеток живучки туркестанской Аjuga turkestanica (Rgl.) - продуцентов фитоэкдистероидов

Callus cultures of Ajuga turkestanica (Rgl.) Briq. (Lamiaceae) were obtained from a wild plant, and the processes of morphogenesis in these cultures were studied. Depending on the hormonal composition of media, it is possible to obtain gemmogenesis or rhizogenesis in the first 6 to 8 growth cycles; after 10-15 growth cycles, the ability of morphogenesis was lost. Suspension cell cultures were initiated from some well-growing calluses. As a result, about one hundred calluses and suspension cell lines were obtained from the Ajuga turkestanica plant cells, a number of which were characterized by intensive growth and were analyzed by the HPLC-MS method for the presence of phytoecdysteroids. In most of the investigated lines, 20-hydroxyecdysone and turkesterone were found, the content of the first being 30-50 times higher than the second (in the most productive lines, 2.0-2.5 mg/g and 0.04-0.05 mg/g dry weight, respectively). An increase in the content of phytoecdysteroids in the in vitro cultivated cells by the end of the growing cycle was observed. However, phytoecdysteroids were not found in many of the obtained cell lines. Further research is needed to clarify the reasons for the presence or absence of phytoecdysteroids in Ajuga turkestanica plant cell cultures. Ajuga turkestanica, plant cell culture, growth regulators, differentiation, gemmogenesis, rhizogenesis, phytoecdysteroids, 20-hydroxy ecdysone, turkesterone The work was financially supported by the Russian Science Foundation (№ 16-14-00126).

Cytotoxicity of Tetrahydropentagamavunon-0 (THPGV)-0 and Tetrahydropentagamavunon-1 (THPGV-1) in Several Cancer Cell Lines

Tetrahydropentagamavunon-0 (THPGV-0) and Tetrahydro-pentagamavunon-1 (THPGV-1), are analogs of a curcumin metabolite, tetrahydrocurcumin, and a derivate of Pentagama-vunon-0 (PGV-0) and Pentagamavunon-1 (PGV-1), respectively. THPGV-0 and THPGV-1 have been successfully synthesized and are investigated for their anticancer potency. Cytotoxic assays were performed toward several cancer cell lines to determine values of the IC 50 against those cell lines. Assessing cytotoxicity in Vero normal cell line showed the selectivity of those compound. THPGV-1 showed highest cytotoxic activity in lymphoma Raji cells, a suspension cell line, with an IC 50 of 180mM. Both THPGV-0 and THPGV-1 showed similar potencies in T47D breast cancer cell line with IC 50 values of 250-270mM. Regardless their high selectivity, however, cytotoxic activities of THPGV-0 and THPGV-1 were lower compared to PGV-0 and PGV-1 in HeLa cervical, T47D breast, and WiDr colon cancer cell lines. Further study using different types of cancer cell lines and confirmation of cell viability by another assays and apoptosis detection may give more benefit.

Scalable Production of AAV Vectors in Orbitally Shaken HEK293 Cells

Adeno-associated virus (AAV) vectors are currently among the most commonly applied for in vivo gene therapy approaches. The evaluation of vectors during clinical development requires the production of considerable amounts of highly pure and potent vectors. Here, we set up a scalable process for AAV production, using orbitally shaken bioreactors and a fully characterized suspension-adapted cell line, HEKExpress. We conducted a proof-of-concept production of AAV2/8 and AAV2/9 vectors using HEKExpress cells. Furthermore, we compared the production of AAV2/9 vectors using this suspension cell line to classical protocols based on adherent HEK293 cells to demonstrate bioequivalence in vitro and in vivo. Following upstream processing, we purified vectors via gradient centrifugation and immunoaffinity chromatography. The in vitro characterization revealed differences due to the purification method, as well as the transfection protocol and the corresponding HEK293 cell line. The purification method and cell line used also affected in vivo transduction efficiency after bilateral injection of AAV2/9 vectors expressing a GFP reporter fused with a nuclear localization signal (AAV2/9-CBA-nlsGFP) into the striatum of adult mice. These results show that AAV vectors deriving from suspension HEKExpress cells are bioequivalent and may exhibit higher potency than vectors produced with adherent HEK293 cells.