Surface hydrophobicity/hydrophilicity of chromatographic stationary phases is one of the important characteristics that influence the chromatographic column performance. On the one hand, the surface should be highly hydrophilic to avoid nonspecific adsorption of sample molecules; on the other hand, the hydrophobic surface is crutial to e.g. separate the molecule isoforms.Therefore, fast and easy characterization method to evaluate the surface „hydrophobic/hydrophilic character" could be valuable.
First stage in the development of this method and the objective of this study was to evaluate the hydrophobicity of test set of 1 mL CIM columns with different ligand chemistries and densities. This was achieved by separation of protein mixture under hydrophobic interaction chromatography (HIC) conditions. Proteins were used since monoliths are used mainly in downstream of large biomolecules.
Moreover, since poor recovery under HIC conditions was observed on some columns, the research was additionally expanded with reversed phase chromatography (RPC) to obtain extra information about even more hydrophobic surface properties of monolithic columns. Therefore, after HIC step the RPC step followed and additional elution of proteins was achieved.
Exosomes are nano-sized vesicles that are released by many different cell types. They are involved in the transport of a wide range of signalling molecules, including mRNA, microRNA and proteins. Exosomes have been found into body fluids and multiple roles have been ascribed to exosomes, in particular in cell signalling where it has been demonstrated their correlation to disease progression and their overexpression as specific tumour cell biomarkers, suggesting their important role in their diagnosis.
This initial screening oriented towards the separation of exosomes from a cell culture supernatant, has been developed by BIA Separations in collaboration with Exosomics Siena. Exosomes used for this study were cultivated in two different cell lines, MeWo and LNCap, and, after the harvesting, a relatively pure target molecule was obtained after several centrifugations, filtrations and batch affinity capture step with a commercial purification kit. In order to speed-up the process and bring current DSP on a higher level, a novel purification approach based on chromatography, using CIM® monolithic columns was investigated. Monolithic supports represent a new generation of chromatographic media. Due to their large inner channel diameters and enhanced mass transfer characteristics, methacrylate monoliths offer efficient and fast separation of large biomolecules like vescicles, pDNA, viruses and monoclonal antibodies. High binding capacity, good product recovery and resolution are also benefits of monoliths. Different samples, (Standard batch purified exosomes, Culture supernatant filtered, Culture supernatant non-filtered), derived from MeWo and LNCap culture media,, were screened. QA, SO3, DEAE and OH CIM 1mL tube - 6μm pore size were screened. CIM® QA - 6μm pores was chosen.
One of the major requirements for pharmaceutical-grade pDNA is its high homogeneity, being mostly in supercoiled (sc) isoform. Chromatographic separation of sc pDNA from open coiled (oc) or linear isoform is challenging due to their similar interactions with the chromatographic phases. Promising separation efficiency of pDNA isoforms was proven on recently developed histamine modified monolithic chromatographic column in descending ammonium sulfate gradient. The aim of the study was to further optimise the chromatographic conditions for sample analysis, where all three isoforms would be baseline separated.
Phosphoproteomics is a branch of proteomics that focuses on deriving a comprehensive view of the extent & dynamics of protein phosphorylation by way of identifying & characterizing proteins that contain a phosphate group as a posttranslational modification. One of the approaches for specific enrichment of phosphopeptides from complex samples is metal oxide affinity chromatography (MOAC), where the specific adsorption results from bridging bidentate bindings formed between the phosphate anions and the surface of a metal oxide, such as TiO2, ZrO2, Fe2O3, and Al2O3. In presented study, a rutile TiO2 nanoparticles were bound to a previously polymerised CIM hydroxy monoliths.
Interactions between antibodies and their antigens are highly selective and therefore immensely popular for affinity chromatography. Consequently, numereous antibody immobilizations were performed on monolithic supports via different activation chemistries in the last decade. Despite the work already done there was no systematic study, where as many as possible activation chemistries were tested for the immobilization of a model monoclonal antibody with subsequent chromatographic characterization of the affinity support. In this work, various preactivated CIM monolithic columns were used for the immobilization of a model monoclonal IgG.
Monolithic ion exchange CIM® (Convective Interaction Media) columns have been proven in quantitative analysis of different immunoglobulins such as IgM and IgG from human plasma or cell supernatants. The separation mechanism is based on ionic interactions between the ion exchange monolith and immunoglobulin that are controlled by salt concentration. Here we present another possibility of IgM determination based on monolithic CIM® OH columns where the interactions may be controlled by changes in salt concentration or by pH increase. A method for quantitative HPLC determination of IgM in cell supernatant with fluorimetric detection was developed on CIM® OH column (0.34 mL) by means of pH increase. Optimal separation of IgM from cell supernatant matrix was achieved by combining acetate and phosphate buffer in a suitable gradient profile. Two different quantification methods, i.e. calibration curve and standard addition.
Determining the concentration of viruses is a crucial step in any production process. The most commonly used methods for virus quantification are either based on the infectivity of the virus (plaque assay, TCID50) determination of their genomic material (qPCR), or protein content (SRID, ELISA) and are very cumbersome and time consuming. HPLC analytical methods represent a fast alternative to these assays since they provide information on the virus content and purity in a matter of minutes. Due to the structural properties of the monolithic supports, monolithic analytical columns offer a great advantage over particle based HPLC columns in terms of time and their ability to separate large biomolecules, like viruses, VLPs, pDNA.
In this poster the performance of the CIMac™ Adeno Analytical Column – a monolith based anion exchange column, designed for fast and reproducible analyses of adenoviruses was evaluated. CIMac Adeno column can be used for designing a fast finger printing method that is applicable for monitoring the DSP production process of adenoviruses. Once the basic analytical parameters like linearity and sensitivity are determined using a purified adenoviral standard, the metod can be applied for quantitative determination of adenoviruses.
Enrichment of phosphopeptides prior to LC-MS analysis is a crucial sample preparation step because of their low stoichiometry in biological sample, longer retention on reversed phase columns, and lower ionization efficiency compared to non-phosphorylated peptides .The use of metal oxides, most prominently of TiO2 enabled efficient and relatively simple phosphopeptide-enrichment. In this study a new monolithic column from BIA Separations containing immobilized TiO2-nanoparticles was tested for its ability to enrich phosphopeptides. The TiO2-column was also tested for possible carryover originating from biological samples. In conclusion, tested monolithic TiO2 columns show significant binding ability for phosphopeptides and are considered as suitable for phosphopeptide enrichment.
The demand for human immunoglobulin is invariably increasing on an annual basis. To satisfy demands, different manufacturing processes are used to isolate immunoglobulins from human plasma. A quest for alternative paths in manufacturing not only requires development of the most economical manufacturing process, but also a rapid method development and development of reliable analytics for manufacturing monitoring. For an efficient improvement of the purification methods as well as for in-process control during manufacturing stage, the usage of reliable and fast analytical techniques are of crucial importance.
Fast and reliable fingerprint-based method for characterization of immunoglobulin G (IgG) prepared from Cohn I+II+III paste in two chromatographic steps is presented. The fingerprint method bases on partial separation of proteins in linear gradient on CIMac QA 0.1 mL column. Partial separation of proteins does not allow simple quantitative analysis of the samples during the IgG production from Cohn I + II + III paste, however, a very accurate qualitative information about the composition of the sample can be obtained in less than 5 minutes.
In recent years bacteriophages were identified as a useful potential tool for different applications such as alternative to antibiotics, detection of pathogenic bacteria, delivery vehicles for protein and DNA vaccines and as gene therapy delivery vehicles. For all listed fields of use it is important that phages are highly purified with preserved biological activity. Phage and other virus purification have traditionally been carried out by CsCl2 density gradient ultracentrifugation, which is however difficult to be scaled-up. An alternative is chromatography, which already proved to be efficient for separation and purification of certain virus types. Methacrylate monoliths (CIM Convective Interaction Media® monolithic columns) were designed for purification of bionanoparticles and they already proved to be very efficient for concentration and purification of several plant and human viruses (influenza A, influenza B, adenovirus type 5, hepatitis A and others).
Our aim was to investigate whether CIM methacrylate monolithic columns can be implemented for purification of phages. Staphylococcus aureus phage VDX-10 was selected. Chromatographic support chemistry and buffer screening led to development of purification method on strong anion exchanger. Optimised single step purification method developed for S. aureus VDX-10 phage on CIM® QA monolithic column resulted in efficient removal of host cell DNA and proteins with high recovery of viable phage.
The challenge of efficient purification of gene therapy vectors
• The most commonly used gene transfer vectors are adenoviruses, lentiviruses, adeno-associated viruses, retroviruses, vaccinia viruses, and pDNA
• Due to their large size and sensitivity to pH, temperature and shear stress, purification is challenging and time-consuming
• A fast and efficient downstream processing purification method is required to isolate sufficient amounts of vectors with the final purity and state that conforms to stringent regulatory demands.
Solution: Convective Interaction Media Monoliths
• Convective interaction media (CIM) monolith chromatography
• Functionalised polydimethacrylate (QA, DEAE, OH, SO3)
• Precisely defined pore sizes
• Radial flow of solute
• Convective mass transfer
Challenges in monitoring the quality of vaccine production
• Process Analytical Technology (PAT) ensures process reproducibility in bioprocessing
• A mechanism to design, analyze and control pharmaceutical manufacturing processes through the measurement of critical process parameters (CPP) which affect product quality attributes (CQA)
• Initiated by the FDA as part of the 21st Century GMP initiative in 2001 with the goal of increasing productivity
• Application of PAT in vaccine development and manufacturing is challenging due to the sample complexity and batch-to-batch variability.
• During the development of an up- and/or down-stream process of the target biomolecule, a fast, accurate and reliable analytical method is requried for determining the quantity and purity of the product intended for human use
Solution: Convective Interaction Media Monoliths
• Monoliths are chromatography media cast as a single block, inserted into a housing
• Highly inter-connected network of channels (1-2 μm) containing functionalised binding sites for large biomolecules (viruses, VLPs, pDNA, antibodies)
• Performance unaffected by increasing the flow rate or molecular size
The development of safe, effective, and affordable vaccines has become a global effort due to its vast impact on overall world health conditions. A brief overview of cancer vaccine characterization techniques, especially in the area of high-resolution mass spectrometry, is presented. It is highly conceivable that the proper use of advanced technologies such mass spectrometry, along with the appropriate chemical and physical property evaluations, will yield tremendous in-depth scientific understanding for the characterization of vaccines in various stages of the development. This work presents the physiochemical and biological characterization of two cancer vaccines: Racotumomab and Her1-ECD. Racotumomab monoclonal antibody is a murine anti-idiotypic antibody that mimics N-glycolyl-GM3 gangliosides. This antibody has been tested as an anti-idiotypic cancer vaccine, adjuvated in Al(OH)3, in several clinical trials for melanoma, breast, and lung cancer. The Her1-ECD is a vaccine preparation based on the extracellular domain of HER1 and it is being evaluated in Phase I clinical study in patients with refractory prostate cancer.
A monolith is a stationary phase made of single piece of porous material. Unlike conventional particle-shaped chromatographic supports, the pores of the monolith are interconnected and form a network of channels with diameters ranging around 1500 nm. The binding sites in these channels are highly accessible for target molecules and since the predominant mass transfer depends on convection rather than diffusion, the dynamic binding capacity is flow independent. These characteristics make the monolithic supports suitable for fast separation and purification of large biomolecules such as proteins, DNA and viruses, which sometimes exceed 200 nm in size and thus have low diffusion constants.
In this work we tried to quantify influenza A virus using an analytical CIM monolith column. First a screening of available CIM stationary phases was performed in order to establish the optimal stationary phase for the binding of the virus. The effect of the mobile phase composition and pH on the recovery and peak shape of the virus was investigated. Linearity was examined. The amount of virus in the flow-through and elution fractions was determined with the haemagglutination assay and the purity of the fractions with SDS PAGE. All experiments were performed with an inactivated Influenza A/Wisconsin PZC whole virus sample that was produced in eggs.
There are two different designs of chromatographic columns concerning the flow profile. Most of today's HPLC columns belong to the group of so-called axial mode operating columns, while the radial ones with a radial flow pattern are more rare. Which type performs better depends on the particular case but it seems that the radial operating columns are attracting interest since they exhibit some beneficial features. One of the main problems of radial operating chromatographic columns is the changing of a mobile phase linear velocity over the chromatographic bed. Because of that, matrix efficiency for porous particulate supports varies by its position within the bed, and overall performance is more difficult to predict.
This problem is not present when the monolithic supports are used, since it was demonstrated that their chromatographic properties are flow unaffected even at the extreme linear velocities. This was confirmed also for the radial operating mode.
The monolith and radial flow housing were designed for extremely high flow rates, up to 70 CV/min, which is the range of the flow rates applied on membranes. This was achieved by proper monolith dimensions with the height of 55 mm, inner diameter of 6.0 mm and thickness of only 4.5 mm.
Monolith chromatography media coupled with metal affinity ligands proved superior to the conventional particle-based matrix as a plasmid DNA (pDNA) purification platform. By harnessing the differential affinity of pDNA, RNA. Host cell proteins and endotoxin to copper ions in the solution a majority of endotoxin (90%) was removed from the alkaline cell lysate using CuCl2-induced precipitation. RNA and remaining endotoxin were subsequently processed by copper immobilized metal affinity column employing either monolith or particle-based matrix where both RNA and endotoxin were removed below detection limit with almost complete recovery of pDNA in the monolith was found to have several advantages in terms of handling feedstocks crowded with RNA in a concentration-independent manner and exhibiting flowrate-independent dynamic binding capacity for RNA. This enabled monolith-based process to be conducted at high feed concentration and flow rate. Resulting in pDNA vaccine purification at a high yield and purity and the process conditions investigated, the use of monolith column gave at least three fold higher productivity for recovery of purified pDNA as compared to the particle- based column, demonstrating its potential as a more rapid and economical platform for pDNA vaccine purification.
The present study describes a new methodology to quantify and monitor the quality of supercoiled (sc) plasmid DHA (pDLIA), using a monolithic column based on anion-exchange chromatography. This analytical method with UV detection allows distinguishing the plasmid isoforms by a NaCl stepwise gradient. The selectivity, Linearity, accuracy, reproducibility and repeatability of the method have been evaluated, and the lower quantification and detection limits were also established. The validation was performed according to the guidelines, being demonstrated that the method is precise and accurate for a sc plasmid concentration up to 200 µg/mL. The main advance achieved by using this monolithic method is the possibility to quantify the sc plasmid in a sample containing other plasmid topologies, in a 4 minutes experiment. This work also intends to evaluate the possibility to assess the sc pDNA present in more complex samples, allowing the control of the samples recovered from different bioprocess steps.
Glycosylation is one of nature mechanism for invreasing the diversity of protein structures affecting biophysical vjaracterostocs and bioactivity. Glycoproteins exist as mixture of different isoforms ("glycoforms"). In this mixture a group od different glyco components is attached to individual glycosylation site. Different glyco componets attached to the same site may have diggerent effect on biophysical charachteristics of glycoproteins. The type of glycosylation and the degree of heterogenity are important for many reasons starting from stability, activity, clinical efficency (toxicity, pharmacokinetics, immunogenicity), to standardization and patentability.
Thus, it is necessary to separate glycoforms and as much as possible to difine the heterogenity i.e. population of of glyco components attached to the singele glycosysilation site.
External invertase is a widely usef model for studying the influance of the glyco-component on protein stability. External invertase from yeast Sccharomyces cerevisiae has 14 potential N-glycosylation sites in the sequence, 13 of which are fully or partially glycosylated with olygomannans of varying sizes.
Extensive research in the last two decades has led to the realization of Immunoglobulin M (IgM) as a potential therapeutic and diagnostic agent for autoimmune diseases, infectious diseases and as an AIDS and cancer vaccine. Growing interest in these molecules has created a need for an accurate, rapid and simple analytical method to measure IgM concentrations during the production (in-process control) in cell culture supernatants as well as in all purification steps in the downstream processing.
Convective interaction media (CIM) monolithic columns has been increasingly recognized as a quantification tool for large molecules. Affinity ligands like protein A and protein G are the most common ligands used for antibody capture and analysis.
Recombinant Adenovirus (rAd) is commonly used for vaccination and gene transfer for cancer applications. This vector is widely used in phase I/II clinical trials. Therefore we believe that upstream and downstream processes should be improved.
We developed a production manufacturing process for rAd serotype 5 n HEK293 grown into disposable fixed-bed iCELLis™ bioreactors (ATMI LifeSciences). The purification process was reduced to one single chromatography step using the Convective Interaction Media, anion exchanger (CIM ® QA monolithic column, Bia Separations).
Briefly, rAd particles were extracted from cells using Triton X-100, depth filtered to discard cell debris, captured and purified out on CIM ® QA. The shallow gradient used for the elution of the vector allowed the separation of different rAd particles populations more or less enriched in full particles. A final step based on Tangential Flow Filtration (TFF) in hollow fibers allowed the removal of remaining impurities and the formulation of the vector batch.
In addition, we developed an analytical method on CIMac™ QA analytical column (Bia Separations) to characterize the different steps of the process, and to track the differences linked to the production runs to increase the robustness of the process. This method provided elution profiles for each step as well as titer of the purified rAd in the final step.
The rAd was produced in an iCELLis™ nano fixed-bed bioreactor (0.5-5.3 m2), purified in a 8mL CIM ® QA monolithic column, scaled up in a medium-scale size 80mL column. We are currently extending the rAd production in a 133m2 iCELLis I000™ bioreactor with a purification step using a 8L CIM® QA monolithic column to purify out up to 1x1015 vector particles.