Enzyme-Linked immunosorbent Assay-Format tissue culture infectious Dose-50 test for titrating dengue virus

Abstract

A dengue nonstructural protein 1 (NS1) antigen capture enzyme-linked immunosorbent assay (ELISA)-based tissue culture infectious dose-50 (TCID 50) test (TCID 50-ELISA) was developed as an alternative to the standard plaque assay for titrating dengue virus. Virus titers obtained by TCID 50-ELISA were comparable to those obtained by the plaque assay and by the traditional TCID 50-cytopathic effect (CPE) test (TCID 50-CPE), with a better reproducibility and a lower coefficient of variation. Quantitative comparison of TCID 50-ELISA and TCID 50-CPE resulted in a correlation coefficient of 0.976. Moreover, this new method showed a wider application to C6/36, Vero E6, BHK-21, and Vero cells compared with other titration methods. In summary, the novel TCID 50-ELISA method described here provides a more reliable and more accurate alternative compared to the plaque assay and TCID 50-CPE for titration of dengue virus. © 2011 Li et al.