Evaluation of a standardised Vi poly-l-lysine ELISA for serology of Vi capsular polysaccharide antibodies.

Evaluation of a standardised Vi poly-l-lysine ELISA for serology of Vi capsular polysaccharide antibodies. Biologicals. 2020 Jun 20;: Authors: Rigsby P, Beamish E, Hockley J, Atkinson E, Hitri K, Jones E, Yang JS, Qadri F, Bachtiar NS, Elias SC, Goel A, Mishra R, Dugyala R, Pasetti MF, Meiring JE, Mbewe M, Gordon MA, Pollard AJ, Logan A, Rijpkema S, anti-Vi IgG working group Abstract Typhoid vaccines based on protein-conjugated capsular Vi polysaccharide (TCVs) prevent typhoid in infants and young children. Analysis of the serum anti-Vi IgG response following immunisation against typhoid confirms the immunogenicity of TCVs and forms an important part of the pathway to licensing. Comparative studies could expedite the licencing process, and the availability of a standardised ELISA method alongside the 1st International Standard (IS) 16/138 for anti-typhoid capsular Vi polysaccharide IgG (human) will facilitate this process. To this end, a non-commercial ELISA based on a coat of Vi and poly-l-lysine (Vi-PLL ELISA) was evaluated by 10 laboratories. Eight serum samples, including IS 16/138, were tested in the standardised Vi-PLL ELISA (n = 10), a commercial Vi ELISA (n = 3) and a biotinylated Vi ELISA (n = 1). Valid estimates of potencies relative to IS 16/138 were obtained for all samples in the Vi-PLL ELISA and the commercial ELISA, with good repeatability and reproducibility evident from the study results and concordant estimate...
Source: Biologicals : Journal of the International Association of Biological Standardization - Category: Biotechnology Authors: Tags: Biologicals Source Type: research