Virus clearance by activated carbon for therapeutic monoclonal antibody purification.

In our previous study, activated carbon (AC) was employed in the purification process of therapeutic monoclonal antibody (mAb) as a replacement for Protein A affinity chromatography. In addition, we established an innovative column-free flow-through purification process using AC filter. In these investigations, the effective clearance of impurities (high-molecular-weight species, low-molecular-weight species, host cell proteins, and DNA) was observed compared to the conventional Protein A platform purification process.

Improving impurities clearance by amino acids addition to buffer solutions for chromatographic purifications of monoclonal antibodies.

The performance of amino acids in Protein A affinity chromatography, anion exchange chromatography and cation exchange chromatography for monoclonal antibody purification was investigated. Glycine, threonine, arginine, glutamate, and histidine were used as buffer components in the equilibration, washing, and elution steps of these chromatographies. Improved clearance of impurity, high molecular weight species (HMW) and host cell proteins (HCP) was observed in the purification processes when using the amino acids as base-buffer constituents, additives or eluents compared with that of buffers without these amino acids.

Measurement of sialic acid content is insufficient to assess bioactivity of recombinant human erythropoietin.

Assessment of biological potency and its comparison with clinical effects are important in the quality control of therapeutic glycoproteins. Animal models are usually used for evaluating bioactivity of these compounds. However, alternative methods are required to simplify the bioassay and avoid ethical issues associated with animal studies.

Rational method for designing efficient separations by chromatography on polystyrene-divinylbenzene resins eluted with aqueous ethanol.

A rational method for designing separation processes by chromatography with polystyrene-divinylbenzene (PS-DVB) resins of different particle diameters (10-400microm) was developed. As model samples, catechin and epigallocatehin gallate (EGCG) were chosen and the mobile phase was an ethanol-water mixture. Linear gradient elution experiments were carried out with different gradient slopes, and the peak ethanol concentration was plotted against the normalized gradient slope.

Treatment with anti-TGF-beta antibody ameliorates chronic progressive nephritis by inhibiting Smad/TGF-beta signaling.

Background: Although short-term treatment with anti-transforming growth factor-beta (TGF-beta) antibody (alphaT) has been shown to prevent early glomerular lesions, its long-term effects and molecular mechanisms, including intracellular signaling, remain poorly understood. We examined whether alphaT treatment induces prevention of renal insufficiency and fibrosis, and affects the TGF-beta/Smad signaling pathway in rats with chronic progressive anti-thymocyte serum (ATS) nephritis induced by repeated ATS injections on days 0 and 7.

Methods: Nephritic and non-nephritic rats were treated with either alphaT or control immunoglobulin (Ig)G twice weekly for 4 weeks from days 7 to 35 (each group, N= 21).