Sepharose HP Research Articles

Spherical nanoparticles can be used as non-penetrating tracers to determine the extra-particle void volume in packed-bed chromatography columns

The optimization of downstream processing in silico can accelerate bioprocess development by limiting experiments to the most promising separation conditions that have been identified using chromatography models. Such models describe protein binding and mass transport in packed-bed columns and thus require precise knowledge about the columns and the resins they contain. One important set of properties is the resin porosities, often determined using combinations of penetrating and non-penetrating tracers. However, the former can be disproportionately small, providing data of limited practical relevance, and the latter can undergo unwanted interactions with the resin, interfering with porosity calculations. Here we characterize and minimize the interactions of three novel hard-sphere non-penetrating tracers with the model resin Q Sepharose HP under various conditions and determine the corresponding inter-particle porosities. We found that conductivities > 100 mS cm−1 were necessary to suppress tracer–resin interactions despite them sharing the same surface charge. We combined these data with those from proteins studied under non-binding conditions, which can be used as authentic penetrating tracers, to determine both the intra-particle and total porosities. Furthermore, we found that the inter-particle porosity was below the theoretical limit of dense sphere packing (25.95%) and provide experimental data showing that the discrepancy is caused by resin particle deformation during the packing of columns under pressure.

Direct Stimulation by Methanol Addition on the Cultured Medium for Methanol Dehydrogenase Protein Purification from Bradyrhizobium japonicum USDA110

Methanol dehydrogenase (MDH) enzyme was purified from Bradyrhizobium japonicum USDA110 cell-free extract. The bacteria were grown in a culture medium with direct 0.5% methanol addition aimed to stimulates the MDH catalytic enzyme activation. Bradyrhizobium japonicum USDA110 MDH enzyme was purified by using 25 mM 2-(N-morpholine) ethanesulfonic acid/MES pH 5.5 buffer and 1 M sodium chloride/NaCl which separated into three columns, the first column was PD-10 for buffer exchange; the second column was HiTrap Sepharose HP to obtain unbonded fraction in the column; and the third column was Mono S 5/50 GL integrated with two pumps HPLC (high-performance liquid chromatography) to obtain pure MDH enzyme for serial changing of 1 M NaCl-25mM MES pH 5.5 with the flow rate at 1 ml/min. The protein concentration and MDH catalytic enzyme activity were observed on each purification process starting from the cell-free extract to pure MDH enzyme. The pure MDH enzyme was obtained by Mono S 5/50 GL-HPLC purification which showed a single band on SDS PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis). The MDH enzyme purification from Bradyrhizobium japonicum USDA110 showed 90-fold purification, a sub-molecular weight of 63 kDa, specific activity at 2.69 U/mg, and optimum activity at a 35oC temperature and pH 9.

Use of mobile phase additives for the elution of bispecific and monoclonal antibodies from phenyl based hydrophobic interaction chromatography resins

Hydrophobic interaction chromatography (HIC) is routinely used in the purification of biopharmaceuticals such as antibodies. However, hydrophobic proteins can be difficult to elute resulting in low recovery of product thereby complicating early phase process development and potentially excluding the use of HIC resins for their manufacture. Mobile phase additives such as hexylene glycol and arginine facilitate protein elution from resins including HIC; therefore, these additives were evaluated toward the recovery and purification of bispecific and monoclonal antibodies from Phenyl Sepharose HP and Capto Phenyl ImpRes resins. The influences of gradient versus step elution as well as superficial linear velocity on product quality were evaluated. Improved protein recovery and reduction of both soluble product aggregate and host cell protein were observed for the tested antibodies with both hexylene glycol and arginine. Furthermore, the impact of salt removal from the HIC load on protein-resin binding was examined providing opportunities to minimize processing time. This method was successfully scaled using a Phenyl Sepharose HP (5 cm i.d. × 20.0 cm) and Capto Phenyl ImpRes (3.2 cm i.d. × 21.4 cm) column demonstrating potential for manufacturing purposes.

Cloning of Oryza sativa N-glycanase gene (OsPNGase A) and its expression in Pichia pastoris

N-glycanase is a class of deglycosylation enzymes, widely used in the study of N-glycosylation modification of glycoprotein. In this study, an N-glycanase gene (OsPNGase A, XM_015775832) with high GC content (69.48%) was cloned from rice and then the yeast secretory expression vector pPICZ(α)A-OsPNGase A was constructed for the purpose of transformation to Pichia pastoris. After induction in Pichia pastoris SMD1168H, the target protein was purified by DEAE Sepharose and HisTrap HP chromatography, with a yield of 12.3 mg OsPNGase A from 1 L fermentation medium, showing a specific activity of 258 U/mg. SDS-PAGE revealed that the purified OsPNGase A was a single band and showed consistentcy with the expected molecular weight. OsPNGase A could act on transferrin recombinantly expressed in rice, avidin recombinantly expressed in corn and horseradish peroxidase. Furthermore, OsPNGase A showed higher activity than commercial PNGase F towards avidin. OsPNGase A displayed the highest digestion activity at pH 6.0 and 40 °C, and was also active in the neutral and alkaline environment. Despite the fact that OsPNGase A was inhibited by reducing agents and surfactants, it still maintained partial enzymatic activity in 100 mmol/L β-ME or DTT. Therefore, the successful expression of rice OsPNGase A provides a new tool for the study of plant glycoproteins and the establishment of yeast secretion expression system lays the foundation for the preparation of PNGase A.

Reaction-Mediated Desorption of Macromolecules: Novel Phenomenon Enabling Simultaneous Reaction and Separation.

Combining chemical reaction with separation offers several advantages. In this work possibility to induce spontaneous desorption of adsorbed macromolecules, once being PEGylated, through adjustment of the reagent composition is investigated. Bovine serum albumin (BSA) and activated oligonucleotide, 9T, are used as the test molecules and 20 kDa linear activated PEG is used for their PEGylation. BSA solid-phase PEGylation is performed on Q Sepharose HP. Distribution coefficient of BSA and PEG-BSA as a function of NaCl is determined using linear gradient elution (LGE) experiments and Yamamoto model. According to the distribution coefficient the selectivity between BSA and PEG - BSA of around 15 is adjusted by using NaCl. Spontaneous desorption of PEG - BSA is detected with no presence of BSA. However, due to a rather low selectivity, also desorption of BSA occurred at high elution volume. A similar procedure is applied for activated 9T oligonucleotide, this time using monolithic CIM QA disk monolithic column for adsorption. Selectivity of over 2000 is obtained by proper adjustment of PEG reagent composition. High selectivity enables spontaneous desorption of PEG-9T without any desorption of activated 9T. Both experiments demonstrates that reaction-mediated desorption of macromolecules is possible when the reaction conditions are properly tuned.

Expression and Purification of Delta Sleep-Inducing Peptide Fused with Protein Transduction Domain and Human Serum Albumin in Pichia pastoris.

Sleep is a natural part of every individual's life. Delta sleep-inducing peptide (DSIP) is a nonapeptide that could promote sleep through the induction of slow wave sleep. However, little is known about the pharmacological effect of DSIP on insomnia. The main objective of this study was to analyze the pharmacological effect of DSIP on insomnia. We designed a fusion protein containing N-terminal TAT-based transduction domain followed by human serum albumin and DSIP and designated this protein as PHD fusion protein. The PHD fusion protein were expressed in Pichia pastoris and purified. Mice were administered single subcutaneous injections three concentrations of PHD fusion protein (0.5, 1, 2 mg/kg), and the pharmacological activity of PHD fusion protein was studied using classic pentobarbitalinduced sleep test. We expressed the PHD fusion protein in P. pastoris; furthermore, the PHD fused protein was purified to near homogeneity by DEAE Sepharose FF, Phenyl Sepharose HP and Blue Sepharose 6 FF. Our result showed that the increase of pentobarbital-induced hypnotic effect characterized by reducing sleep latency and prolonged sleep duration was observed for increasing concentrations of PHD fusion protein (P<0.05); moreover, different dose of PHD fusion protein could induce the mice to re-sleep in a dose-dependent manner, whereas higher doses of PHD fusion protein (1.0, 2.0 mg/kg) significantly increased the rate of sleep re-onset compared with the vehicle group of mice (P<0.05). PHD fusion protein increased the hypnotic effects of pentobarbital by reducing sleep latency and prolonged sleep duration. The present study suggested PHD fusion protein could be a new drug candidate for insomnia.

460. Purification of AAV8 Using a Prototype Affinity Resin Compatible with cGMP Manufacturing

Affinity interaction based resins have long been the foundation for various purification platforms of biological molecules. For the purification of rAAV, the affinity resin AVB Sepharose HP (AVB) has been used to successfully purify a number of different serotypes. However, to date the use of AVB for the purification of the AAV8 serotype has been relatively unsuccessful due in part to modest binding capacity. In this work we investigate the use of a new, prototype affinity resin for the purification of AAV8 from crude feed streams. Performance of the AVB and prototype resins were directly compared for the purification of selected AAV8 feed streams. Differences in capacities, loading steps, wash step tolerances and elution steps will be discussed. In addition, the resulting performance of purifying AAV8 using the prototype resin is directly compared against the best case performance of the AVB resin purifying a different serotype more commonly used on AVB. Finally, the scale-up use of the prototype resin from bench to manufacturing will be discussed. These results demonstrate that the prototype affinity resin is a viable option for the scaleable, chromatographic purification of AAV8 from crude harvest streams.

Fast Protein Liquid Chromatography를 이용한 황색포도상구균 장독소 B 분리

The aim of this study is to develop a method to separate and purify the Staphylococcal enterotoxin B (SEB). The method was based on fast protein liquid chromatography (FPLC) along with gel filtration (GF) after cation exchange chromatography (CIEX) treatment. Various columns such as CM sepharose HP, Cellufine C-500, WorkBeads 40S for CIEX, and GF on Sephacryl S-100 for GF were compared in terms of separation efficiency. Consequently, Work- Beads 40S along with Sephacryl S-100 produced best separation performance. Separated SEB with developed method was verified with ELISA assay. Purified SEB with the method can be used to manufacture rapid detection kit or antibodies.

Alkaline cation-exchange chromatography for the reduction of aggregate and a mis-formed disulfide variant in a bispecific antibody purification process.

During the purification development of a bispecific antibody, cation-exchange chromatography was screened for its ability to separate a prominently expressed (>12%) mis-formed disulfide bond variant, termed MAb-diabody, and aggregate from the product of interest. The influence of pH, product load (g of product per liter of resin) and linear velocity on the separations were evaluated for the strong cation-exchange resins SP Sepharose HP and POROS(®) HS50. Cation-exchange chromatography is commonly operated distant to the isoelectric point of a molecule, generally leading to acidic conditions for antibody purification. However, the results herein demonstrated improved removal of MAb-diabody with increasing pH, resulting in reduction of MAb-diabody content greater than 12-fold when operating near the alkaline pI of the product. This approach was successful over a range of linear velocities and g/L of resin loading. Aggregate removal was less affected by pH and was effectively reduced from 10.9% to less than 3% for each condition. Furthermore, this method was successfully scaled to a 60 cm diameter column using SP Sepharose HP resin.

Novel Ubiquitin-derived High Affinity Binding Proteins with Tumor Targeting Properties

Targeting effector molecules to tumor cells is a promising mode of action for cancer therapy and diagnostics. Binding proteins with high affinity and specificity for a tumor target that carry effector molecules such as toxins, cytokines, or radiolabels to their intended site of action are required for these applications. In order to yield high tumor accumulation while maintaining low levels in healthy tissues and blood, the half-life of such conjugates needs to be in an optimal range. Scaffold-based binding molecules are small proteins with high affinity and short systemic circulation. Due to their low molecular complexity, they are well suited for combination with effector molecules as well as half-life extension technologies yielding therapeutics with half-lives adapted to the specific therapy. We have identified ubiquitin as an ideal scaffold protein due to its outstanding biophysical and biochemical properties. Based on a dimeric ubiquitin library, high affinity and specific binding molecules, so-called Affilin® molecules, have been selected against the extradomain B of fibronectin, a target almost exclusively expressed in tumor tissues. Extradomain B-binding molecules feature high thermal and serum stability as well as strong in vitro target binding and in vivo tumor accumulation. Application of several half-life extension technologies results in molecules of largely unaffected affinity but significantly prolonged in vivo half-life and tumor retention. Our results demonstrate the utility of ubiquitin as a scaffold for the generation of high affinity binders in a modular fashion, which can be combined with effector molecules and half-life extension technologies.

Analytical characterization of a monoclonal antibody therapeutic reveals a three-light chain species that is efficiently removed using hydrophobic interaction chromatography

Size exclusion high performance liquid chromatography analysis of a human monoclonal antibody (mAb) showed the presence of a new species that eluted with a retention time between the dimeric and monomeric species of the antibody. Extensive characterization of this species, referred to as “shoulder,” indicated that it was a mAb containing an extra light chain and had a molecular weight of approximately 175 kDa. The extra light chain was found to be non-covalently associated with the Fab portion of the protein. The relative amount of shoulder (typically 1−3% of the total mAb present) varied with the Chinese hamster ovary cell line producing the mAb and was not influenced by the growth conditions. Our three-step mAb purification platform using protein A, anion exchange, and cation exchange process steps was successful at removing dimer and higher and lower molecular weight species, but not the shoulder impurity. It was found that hydrophobic interaction chromatography could be used in place of cation exchange to exploit the subtle differences in hydrophobicity between monomer and shoulder. We developed an antibody polishing process using Butyl Sepharose HP resin that is capable of removing the majority of high and low molecular weight impurities yielding 99% pure mAb monomer, virtually devoid of the shoulder species, with a step recovery of about 80%.

Purification and identification of a clotting protein from the hemolymph of Chinese shrimp (Fenneropenaeus chinensis)

The clotting protein (CP) plays important and diverse roles in crustaceans, such as coagulation and lipid transportation. A clotting protein was purified from the hemolymph of Chinese shrimp Fenneropenaeus chinensis (named as Fc-CP) with Q sepharose HP anion-exchange chromatography and phenyl sepharose HP hydrophobic interaction chromatography. Fc-CP was able to form stable clots in vitro in the presence of hemocyte lysate and Ca2+, suggesting that the clotting reaction is catalyzed by a Ca2+-dependent transglutaminase in shrimp hemocytes. The molecular mass of Fc-CP was 380 kDa under non-reducing conditions and 190 kDa under reducing conditions as was determined with SDS-PAGE. CP exists as disulfide-linked homodimers and oligomers. The N-terminal amino acid sequence of Fc-CP was identical to that of shrimps including Penaeus monodon, Farfantepenaeus paulensis and Litopenaeus vannamei; and similar to that of other decapods. The purified Fc-CP was digested with trypsin and verified on an ABI 4700 matrix-assisted laser desorption/ionization tandem time-of-flight (MALDI-TOF/TOF) mass spectrometry. Our results will aid to better understanding the coagulation mechanism of shrimp hemolymph.

Gly m 2S albumin is a major allergen with a high diagnostic value in soybean-allergic children

Gly m 2S albumin is a major allergen with a high diagnostic value in soybean-allergic children

Dynamic behavior of binary component ion-exchange displacement chromatography of proteins visualized by confocal laser scanning microscopy

Confocal laser scanning microscopy (CLSM) was introduced to visualize particle-scale binary component protein displacement behavior in Q Sepharose HP column. To this end, displacement chromatography of two intrinsic fluorescent proteins, enhanced green fluorescent protein (eGFP) and red fluorescent protein (RFP), were developed using sodium saccharin (NaSac) as a displacer. The results indicated that RFP as well as eGFP could be effectively displaced in the single-component experiments by 50mmol/L NaSac at 120 and 140mmol/L NaCl whereas a fully developed displacement train with eGFP and RFP was only observed at 120mmol/L NaCl in binary component displacement. At 140mmol/L NaCl, there was a serious overlapping of the zones of the two proteins, indicating the importance of induced-salt effect on the formation of an isotachic displacement train. CLSM provided particle-scale evidence that induced-salt effect occurred likewise in the interior of an adsorbent and was synchronous to the introduction of the displacer. CLSM results at 140mmol/L NaCl also demonstrated that both the proteins had the same fading rate at 50mmol/L NaSac in the initial stage, suggesting the same displacement ability of NaSac to both the proteins. In the final stage, the fading rate of RFP in the adsorbent became slow, particularly at lower displacer concentrations. In the binary component displacement, the two proteins exhibited distinct fading rates as compared to the single component displacement and the remarkable lagging of the fading rate was observed in protein displacements. It suggested that the co-adsorbed proteins had significant influence on the formation of an isotachic train and the displacement chromatography of the proteins. Therefore, this research provided particle-scale insight into the dynamic behavior and complexity in the displacement of proteins.

Tris(hydroxymethyl)aminomethane‐functionalized agarose particles: Parameters affecting the binding of bovine serum albumin

A new protein adsorbent is introduced based on the coupling of the common buffer ion, tris(hydroxymethyl)aminomethane, to the agarose gel Sepharose HP from GE Healthcare Bio-Sciences AB, Uppsala, Sweden. The article describes the synthesis of the new adsorbent and the use of BSA as a model in a binding study. By optimization of the coupling procedure, a maximum ligand density of 63.5 μmol/mL gel could be obtained. Adsorption equilibria were investigated in the pH range 5.0-8.0 and at salt concentrations of 0-0.4 mol/L. Binding of BSA under different conditions indicated that both electrostatic interaction and hydrogen bonding were involved in the adsorption process where the former played a major role.

Expression, purification, and molecular analysis of the Necator americanus glutathione S-transferase 1 (Na-GST-1): A production process developed for a lead candidate recombinant hookworm vaccine antigen

The enzyme Necator americanus glutathione S-transferase 1 (Na-GST-1) belongs to a unique Nu class of GSTs and is a lead candidate antigen in a bivalent human hookworm vaccine. Here we describe the expression of Na-GST-1 in the yeast Pichia pastoris at the 20L manufacturing scale and its purification process performed by three chromatographic steps, comprised of a Q Sepharose XL anion exchange column, followed by a Butyl Sepharose HP hydrophobic affinity column and a Superdex 75 size-exclusion column. Approximately 1.5g of recombinant protein was recovered at an overall process yield of 51%, with a purity grade of 98% and the absence of detectable host cell protein. By mass spectrometry the recombinant protein exhibits a mass of 23,676Da, which closely matches the predicted molecular mass of the protein. The expression and purification methods described here are suitable for further scale-up product development and for its use to design formulation processes suitable to generate a vaccine for clinical testing.

Bioactivity and pharmacokinetics of two human serum albumin-thymosin alpha1-fusion proteins, rHSA-Talpha1 and rHSA-L-Talpha1, expressed in recombinant Pichia pastoris.

Thymosin-alpha1 (Talpha1) is indicated for the treatment of certain viral infections, including hepatitis B and C, and cancers, such as melanoma. In this paper, the fusion genes encoding human serum albumin (HSA) and Talpha1 with (rHSA-L-Talpha1) and without a linker peptide (rHSA-Talpha1) were constructed and overexpressed in P. pastoris. Through the process of ion interaction chromatography (Q-Sepharose F.F), hydrophobic interaction chromatography (Phenyl Sepharose HP) and affinity chromatography (Blue Sepharose F.F), the purity of fusion proteins was greater than 97%. In contrast to the reactivity of normal spleen cells to Con A, the data of in vitro murine spleen lymphocytes proliferation experiment suggested that spleen cells achieved a higher degree of T cell maturation after rHSA-L-Talpha1, rHSA-Talpha1 and Talpha1 treatments, respectively. Moreover, rHSA-L-Talpha1, rHSA-Talpha1 and Talpha1 can also antagonize dexamethasone-induced apoptosis of thymocyte sub-populations. In hydrocortisone-induced immunosuppression mice (in vivo experiments), after subcutaneous injections with two fusion proteins and Talpha1 for seven consecutive days, the net increment of body weight, the spleen index and the thymus index were significantly improved. Simultaneously, the increase in SOD level and the decrease in MDA level in plasma were observed. The pharmacokinetic data of rHSA-L-Talpha1 and rHSA-Talpha1 administered in rats showed an improved pharmacokinetic profile with a conspicuous prolonged half life. The analysis of bioactivity and pharmacokinetics suggested that fusion proteins rHSA-L-Talpha1 and rHSA-Talpha1 were new drug candidates.

Affinity purification of viral protein having heterogeneous quaternary structure: Modeling the impact of soluble aggregates on chromatographic performance

Prokaryote-expressed polyomavirus structural protein VP1 with an N-terminal glutathione-S-transferase tag (GST-VP1) self-assembles into pentamer structures that further organize into soluble aggregates of variable size (3.4 × 10 2–1.8 × 10 4 kDa) [D.I. Lipin, L.H.L. Lua, A.P.J. Middelberg, J. Chromatogr. A 1190 (2008) 204]. The adsorption mechanism for the full range of GST-VP1 soluble aggregates was described assuming a dual-component model [T.Y. Gu, G.J. Tsai, G.T. Tsao, AICHE J. 37 (1991) 1333], with components differentiated by size, and hence pore accessibility, rather than by protein identity. GST-VP1 protein was separated into two component groups: aggregates small enough to access resin pores (LMW: 3.4 × 10 2–1.4 × 10 3 kDa) and aggregates excluded from the resin pores (HMW: 9.0 × 10 2–1.8 × 10 4 kDa). LMW aggregates bound to resin at a higher saturation concentration (29.7 g L −1) than HMW aggregates (13.3 g L −1), while the rate of adsorption of HMW aggregates was an order of magnitude higher than for LMW aggregates. The model was used to predict both batch and packed bed adsorption of GST-VP1 protein in solutions with known concentrations of HMW and LMW aggregates to Glutathione Sepharose HP resin. Asymmetrical flow field flow fractionation with UV absorbance was utilized in conjunction with adsorption experimentation to show that binding of HMW aggregates to the resin was strong enough to withstand model-predicted displacement by LMW aggregates. High pore concentrations of LMW aggregates were also found to significantly inhibit the diffusion rate of further protein in the resin pores. Additional downstream processing experimentation showed that enzymatic cleavage of LMW aggregates to remove GST tags yields more un-aggregated VP1 pentamers than enzymatic cleavage of HMW aggregates. This model can be used to enhance the chromatographic capture of GST-VP1, and suggests an approach for modeling chromatographic purification of proteins that have a range of quaternary structures, including soluble aggregates.

Purification and Characterization of an α-Mannosidase from the Tropical Fruit Babaco (Vasconcellea × Heilbornii Cv. Babaco)

An alpha-mannosidase (EC 3.2.1.24) present in the lyophilized latex of babaco ( Vasconcellea heilbornii ) has been purified to apparent homogeneity by native PAGE. The purification involves a three-step procedure with successive anion exchange with Q Sepharose HP, lectin affinity chromatography using ConA Sepharose 4B, and gel filtration using Superdex 200 prep grade. The molecular mass was determined to be in the range of 260-280 kDa by Superdex 200 prep grade gel filtration, and isoelectric focusing showed a pI range between 5.85 and 6.55, suggesting different glycosylated isoforms. The optimal temperature for the alpha-mannosidase was determined to lie between 50 and 60 degrees C, and the optimal pH was 4.5 at 50 degrees C. The K(m) value for p-nitrophenyl alpha-mannopyranoside (pNPM) was found to be 1.25 mM and the V(max), 2.4 microkat mg(-1) at 50 degrees C and 1.94 microkat mg(-1) at 40 degrees C. The pure alpha-mannosidase was specific for mannose and did not display activity for any other tested synthetic substrates.

Adsorption of plasmid DNA on anion exchange chromatography media

Anion exchange chromatography (AEC) is a useful and effective tool for DNA purification, but due to average pore sizes between 40 and 100 nm most AEC resins lack truly useful binding capacities for plasmid DNA (pDNA). Equilibrium binding capacities and uptake kinetics of AEC media including conventional media (Source 30 Q, Q Sepharose HP), a polymer grafted medium (Fractogel EMD DEAE (M)), media with large pores (Celbeads DEAE, PL SAX 4000 A 30 microm) and a monolithic medium (CIM-DEAE) were investigated by batch uptake or shallow bed experiments at two salt concentrations. Theoretical and experimental binding capacities suggest that the shape of the pDNA molecule can be described by a rod with a length to diameter ratio of 20:1 and that the molecule binds in upright position. The arrangement of DNA like a brush at the surface can be considered as entropy driven, kind of self-assembly process which is inherent to highly and uniformly charged DNA molecules. The initial phase of adsorption is very fast and levels off, associated with a change in mass transfer mechanism. Feed concentrations higher than 0.1 mg/mL pDNA pronounce this effect. Monolithic media showed the fastest adsorption rate and highest binding capacity with 13 mg pDNA per mL.