N-terminal derivatives of tumor necrosis factor purified by microporous PTFE membranes

摘要

A process is disclosed for the purification of recombinantly produced biologically active proteins in which a solution containing a mixture of materials, including the biologically active protein, is passed through a continuous porous hydrophobic membrane, and the fraction enriched in the biologically active protein is recovered. Hydrophobic proteins such as TNF and recombinant ricin toxin A chain may be purified according to the process. Conditions for enhanced recovery of purified TNF using the process are disclosed. A highly purified TNF comprising 95% or greater TNF as determined by SDS-PAGE analysis, with an endotoxin content of less than 0.1 ng/mg TNF which is substantially free of pyrogens by the USP rabbit pyrogen test at a dosage range of 1.0 to 2.4x105 U/kg, is obtained.