WHO/BS/2014.2235 International collaborative study to evaluate and establish the 1st WHO Reference Reagent for Anti-Malaria (Plasmodium falciparum) human serum

Overview

A World Health Organization (WHO) sponsored meeting in 2005 identified that there was a need to develop an immunoassay standard for anti-malaria Plasmodium falciparum (Pf) as an important and urgent requirement for progress in the development of malaria vaccines. A candidate anti-malaria (Pf) Reference Reagent has been developed using diluted human defribinated plasma. The freeze dried human diluted antiserum preparation was evaluated for its suitability as a Reference Reagent containing antibodies to malaria P. falciparum antigens in an international collaborative study. Sixteen laboratories from twelve different countries participated in the study. Lyophilized ampoule preparations were quantified using Enzymelinked immunosorbent assay (ELISA). Based on the results from this collaborative study, it is proposed that this anti-malaria (Pf) human serum preparation (NIBSC code: 10/198) is established by the WHO Expert Committee on Biological Standardization (ECBS) in October 2014, as the First WHO Reference Reagent of anti-malaria (Plasmodium falciparum) human serum with assigned an arbitrary unitage of 100 units (U) per ampoule.

The intended uses of this Reference reagent, a single multivalent preparation, are (1) to allow cross-comparisons of results of vaccine trials performed in different centers/ with different products; (2) to facilitate standardization and harmonization of immunological assays used in epidemiology research; and (3) to allow optimization and validation of immunological assays used in malaria vaccine development.