In the early 1970s there were a number of initiatives to standardise immunoglobulin measurements at national levels. This was followed, in 1992, by the release of “Certified Reference Material 470” (CRM 470) by the College of American Pathologists and The Bureau Communitaire de Référence. CRM 470 was prepared from serum collected from several hundred healthy donors in five European cities, which was pooled and processed to produce approximately 40,000 vials, each containing 1 mL of lyophilised serum. After value assignments by reference laboratories in Europe and the USA, this material was accepted as the international standard for 15 commonly measured plasma proteins, including IgG, IgA and IgM .
By 2008, stocks of CRM 470 were becoming exhausted and the Institute for Reference Materials and Measurements in collaboration with The International Federation of Clinical Chemistry, oversaw an initiative to replace CRM 470 with a new, similar protein reference preparation (DA470k) . Most proteins that had been standardised with CRM 470 were transferred to DA470k, including IgG, IgA and IgM.