Seventh WHO informal consultation on standards for cytokines, growth factors and endocrinological substances.

The seventh WHO Informal Consultation on Standards for Cytokines, Growth Factors and Endocrinological Substances was held at The National Institute for Biological Standards and Control (NIBSC) on 20-21 October 2003. Several issues relating to biological standardization and the establishment of new reference materials were discussed. In particular, recent regulatory requirements within the European Union, which have implications for potency assignments for WHO international standards (IS) and other biological reference materials, were discussed. As a priority, the data on candidate reference materials proposed to the November 2003 WHO Expert Committee on Biological Standardization (ECBS) as proposals to the ECBS to establish as IS or reference reagents (RR) were reviewed. Candidate reference materials, including those for human interferon beta (IFN-β), human tumour necrosis factor alpha (TNF-α), human thyroid stimulating hormone (TSH) and human luteinizing hormone (LH) were discussed and analyzed in detail. In addition, the immunogenicity of therapeutic proteins, including interferons, cytokines and hormones, together with a specific proposal to adopt a standard method for the calculation and reporting of results of interferon neutralizing antibody tests were reviewed and discussed. Lastly, the on-going cytokine and hormone standardization programme at NIBSC was reviewed.