A simple scheme for large scale purification of urine – Derived Bence Jones Kappa protein

Abstract

We have investigated and optimized purification process, suitable for industrial scale, to obtain high purity grade Bence Jones Kappa Protein (‘BJK-Protein’), while preserving its physiological properties and functions. BJK-Protein was obtained from a biological waste product i.e. human urine of renal failure patients. Isolated ‘BJK-Protein’ was analyzed by electrophoresis, western blotting, double immunodiffusion, SEC-HPLC assay and Mass Spectrometry (MS). The relative molecular mass of ‘BJK-Protein’ is 23054.2 Da. Moreover, dimer forms of ‘BJK-Protein’ were also detected in SDS-PAGE and mass spectrum corresponding to 46054.4 Da. The results of western blotting, immunoelectrophoresis, SEC-HPLC assay, and mass spectrometry analysis indicate a high purity (>99 %) of ‘BJK-Protein’. Peptide mass fingerprint analysis of ‘BJK-Protein’ yielded peptides that partially matches the known database sequences of kappa variable region (KV139_HUMAN) of immunoglobulin. This protein was found to be stable up to 20 months at 2–8 °C temperature and also found negative for major undesirable viral markers as well as bacterial endotoxin. With this purification approach, the cost of purified ‘BJK-Protein’ is significantly reduced as compared to the current market price of Kappa light chain available in international market.