Evaluation of 1<sup>st</sup> WHO anti-malaria reference reagent for competition ELISA harmonisation and development of ADAMSEL analytical platform.
Khatri B., Riese P., Shkarlet H., Mortier D., McShane H., Bowyer PW., Remarque E.
This study focuses on harmonising the competition ELISA (cELISA) assay for Plasmodium falciparum (P. falciparum), using the 1st WHO reference reagent for anti-malaria (P. falciparum) human reference serum (10/198). Antibody-mediated immune responses against the Apical Membrane Antigen 1 (AMA1) play a significant role in protection against malaria. However, the sequence diversity of AMA1 and cross-reactivity among variants pose challenges in assessing antibody responses. To address this, the cELISA assay was selected to examine cross-reactive antibody responses against different variants. The harmonisation process for cELISA was performed in three laboratories. The 10/198 served as an internal standard for the calculation of IgG concentrations in the cELISA using ADAMSEL software. Additionally, a novel semi-automated analytical tool was developed in the R-statistics environment. This tool is freely available for download and streamlines generating results while minimising human error. This study demonstrated the effectiveness of the 1st WHO reference reagent as a standard for cELISA. Additionally, the ADAMSEL software and R-platform tool provide a user-friendly and accessible tool for the analysis of cELISA data. Its automation capabilities improve efficiency and ensure global accessibility at no cost, benefitting laboratories with limited resources.