Comparative Assay on Dengue IgM-ELISA Using Reagents From 2 Sources

Abstract

In order to distribute dengue IgM-capture ELISA to the peripheral laboratories, supply of key reagents should be established by local production. In this study, comparative IgM-capture ELISA was carried out on a total of 237 sera using key reagents from 2 sources. The current set consisted of suckling mouse brain (SMB)-derived dengue type 2 (D2) antigen and a D2 monoclonal antibody (MAb) supplied from the United States. While an alternative set was supplied by one of the authors, consisting of tissue culture-derived dengue antigen (TCA) and MAb established in USM. When the IgM-ELISA results were compared with those by the hemagglutination-inhibition (HI) test as a gold standard, the sensitivity was 50.0% by the current set and 75.0% by the alternative set of reagents, respectively. While the specificity was 95.2% by the current set and 90.3% by the alternative set of reagents. The results showed that the alternative set of reagents can effectively be used in dengue IgM-ELISA and is significantly more sensitive than the current set of reagents (Chi SQR=12.26, P<0.01) at less than 1% risk. However there is no significant difference in specificity between the two reagents (Chi SQR=2.45, 0.5>P>0.1) at 10% risk.