title: Purification and biochemical characterization of functional complement factor H from human plasma fractions.
abstract: OBJECTIVE
  Complement factor H (CFH) acts as major regulator of the alternative pathway of complement and its mutations and polymorphisms predispose to various human diseases. We aimed to develop a scalable purification process of CFH from human plasma fractions to supply a pathogen-safe and functional CFH concentrate.
  
  
  METHODS
  Starting with intermediates of cold ethanol fractionation of plasma, CFH purification was performed with three chromatographic steps including solvent detergent treatment and nanofiltration. CFH functionality was tested by a haemolysis assay using sheep erythrocytes, by determining decay acceleration activity on C3 convertases and cofactor activity of C3b cleavage. CFH identity was confirmed by Western blot and mass spectrometry.
  
  
  RESULTS
  Three scalable chromatographic steps highly purified full-length and native CFH from human plasma fractions. The purification process enabled the removal of truncated and dysfunctional CFH species, yielding a native CFH concentrate as demonstrated in sensitive functional in vitro assays.
  
  
  CONCLUSIONS
  This novel process provides a pathogen-safe and functional CFH concentrate that can be produced on an industrial scale and is suitable for pre-/clinical studies.
authors.affiliation: Octapharma PPGmbH, Research & Development, Vienna, Austria. hubert.brandstaetter@octapharma.com
authors.forename: H
authors.initials: H
authors.lastname: Brandstätter
authors.forename: P
authors.initials: P
authors.lastname: Schulz
authors.forename: I
authors.initials: I
authors.lastname: Polunic
authors.forename: C
authors.initials: C
authors.lastname: Kannicht
authors.forename: G
authors.initials: G
authors.lastname: Kohla
authors.forename: J
authors.initials: J
authors.lastname: Römisch
mesh_terms: D000818:Animals; D002499:Centrifugation, Density Gradient; D003176:Complement C3 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017242:Complement Factor H / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D006801:Humans; D013058:Mass Spectrometry; D011110:Polymorphism, Genetic; D011485:Protein Binding; D012756:Sheep
chemical_list: D003176:Complement C3; D017242:Complement Factor H