Patent ID: 8304524

Claim:
A method for preparing an enriched Factor H composition from plasma, the method comprising the steps of: (a) precipitating proteins from a cryo-poor plasma fraction, in a first precipitation step, with between about 6% and about 10% alcohol at a pH of between about 7.0 and about 7.5 to obtain a first precipitate and a first supernatant; (b) precipitating Factor H from the first supernatant, in a second precipitation, step, with between about 20% and about 30% alcohol at a pH of between about 6.7 and about to form a second precipitate; (c) re-suspending the second precipitate to form a suspension; (d) mixing finely divided silicon dioxide (SiO 2 ) with the suspension from step (c); (e) separating the suspension to form a filter cake and a supernatant; and (f) extracting Factor H from the filter cake with a Factor H extraction buffer having a pH of about 4.0-5.5 or about 6.0-9.0, thereby preparing an enriched Factor 1-1 composition.