Separation of protein C from Cohn Fraction IV-1 by mini-antibody

Human protein C (PC) is a natural anticoagulant, antithrombotic, anti-inflammatory, and anti-apoptotic in the bloodstream. PC deficiency can lead to abnormal blood clot formation inside blood vessels, possibly causing heart attack, stroke, skin necrosis, or even death. PC can be, therefore, a valuable therapeutic with little side effect, unlike the currently used anti-coagulants. To reduce the cost involved in immuno purification of PC from blood plasma, single chain variable fragments (mini-Mab) are being produced by recombinant E. coli using phagemid technique. As an economic means of purifying the PC specific mini-Mab, metal affinity chromatography (IMAC) purification process was also investigated. Then using the purified mini-Mab, the feasibility of PC purification from the Cohn Fraction IV-1 was examined. Cohn Fraction IV-1 is usually a discarded side-stream from the blood plasma fractionation of human serum albumin. It holds 90% of PC in plasma, but is very cheap. Preliminary study of PC purification from the Cohn Fraction IV-1 showed 16% purification yield using mini-Mab immobilized NHS-activated Sepharose. The economic analysis for PC purification using mini-Mab showed that the overall process was found to be tens of times cheaper than that using Mab.