Comparison of five commercial enzyme-linked immunosorbent assays for detection of antibodies to Bordetella pertussis

Measuring antibodies to Bordetella pertussis antigens is mostly done by enz yme-linked immunosorbent assays (ELISAs), We compared the performance of fi ve commercially available ELISA kits with the help of 65 serum specimens wh ich were repetitively tested for evaluation of the kits. The specimens cont ained 20 paired serum samples from patients with clinical pertussis, 15 sam ples were from children vaccinated with a diphtheriatetanus-acellular pertu ssis vaccine, seven specimens were taken from an interlaboratory comparison of ELISAs, and there were three reference preparations from the Food and D rug Administration's (FDA's) Laboratory of Pertussis and from our laborator y. Reference values were obtained from the FDA Or from results obtained wit h an in-house ELISA. Commercial ELISAs were compared with respect to their reproducibility and variability, their ability to detect significant titer rises in paired serum samples, their ability to detect an immune response a fter vaccination, and the comparability of semiquantitative and quantitativ e results. Reproducibility was generally good (>89%), intra-assay variation ranged from 2.3 to 28.7%, and indeterminate results were recorded in up to 18.5% of all specimens, Most kits correctly identified the antibody respon se to an acellular pertussis vaccine. None of the commercial kits identifie d all cases of pertussis correctly, and the sensitivity ranged between 60 a nd 95%. All five commercial ELISAs showed great discrepancies when comparin g semiquantitative results and contained obviously different antigen prepar ations, Our data suggest that the five commercial ELISAs tested here need f urther improvement and standardization.