title: Purification and characterisation of anti-pneumococcal capsular polysaccharide IgG immunoglobulins.
abstract: OBJECTIVE
  The production of reference materials for quantifying pneumococcal antibody concentrations relies upon large scale vaccination. An alternative simple, reproducible protocol has been developed for the affinity purification of 23 serotype anti-pneumococcal capsular polysaccharide (PCP) IgG immunoglobulins.
  
  
  METHODS
  The purification protocol utilised IgG fractionation, capsular polysaccharide (CPS) adsorption, and affinity chromatography using Pneumovax®-Sepharose. Purification efficiency and method reproducibility were assessed by comparison of 4 batches of anti-PCP IgG. Immunoglobulin composition was determined using nephelometry and functionality was evaluated using VaccZyme™ ELISAs.
  
  
  RESULTS
  Anti-PCP IgG preparations were ≥95% pure by SDS-PAGE analysis with no contaminating IgA or IgM immunoglobulins or IgG antigen specific antibodies towards haemophilus influenzae b, diphtheria toxoid or tetanus toxoid. The predominant IgG subclass in the preparation was IgG2.
  
  
  CONCLUSIONS
  This novel purification procedure produced highly specific anti-PCP IgG preparations that compared well to both Lot 89SF and 007sp international serum standards and could be used as an alternative method for the production of reference materials.
authors.affiliation: The Binding Site Group Ltd, 8 Calthorpe Road, Birmingham, B15 1QT, United Kingdom. Electronic address: antony.parker@bindingsite.co.uk.
authors.forename: Antony R
authors.initials: AR
authors.lastname: Parker
authors.affiliation: The Binding Site Group Ltd, 8 Calthorpe Road, Birmingham, B15 1QT, United Kingdom.
authors.forename: Emma
authors.initials: E
authors.lastname: Lock
authors.affiliation: The Binding Site Group Ltd, 8 Calthorpe Road, Birmingham, B15 1QT, United Kingdom.
authors.forename: Asma
authors.initials: A
authors.lastname: Iftikhar
authors.affiliation: The Binding Site Group Ltd, 8 Calthorpe Road, Birmingham, B15 1QT, United Kingdom.
authors.forename: Richard
authors.initials: R
authors.lastname: Barber
authors.affiliation: The Binding Site Group Ltd, 8 Calthorpe Road, Birmingham, B15 1QT, United Kingdom.
authors.forename: Phil D
authors.initials: PD
authors.lastname: Stubbs
authors.affiliation: The Binding Site Group Ltd, 8 Calthorpe Road, Birmingham, B15 1QT, United Kingdom.
authors.forename: Stephen
authors.initials: S
authors.lastname: Harding
authors.affiliation: The Binding Site Group Ltd, 8 Calthorpe Road, Birmingham, B15 1QT, United Kingdom.
authors.forename: Gregg L F
authors.initials: GL
authors.lastname: Wallis
mesh_terms: D000907:Antibodies, Bacterial / Q000276:immunology; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology / Q000302:isolation & purification*; D012015:Reference Standards; D015203:Reproducibility of Results; D013296:Streptococcus pneumoniae / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G
keywords: IgG; Pneumovax; capsular; pneumococcal; polysaccharide; serotypes