http://repub.eur.nl/res/aut/4889/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/9522/ 2000-01-01T00:00:00Z The performance of six commercially available immunoassay systems for the detection of dengue virus-specific immunoglobulin M (IgM) and IgG antibodies in serum was evaluated. These included two IgM and IgG enzyme immunoassays (EIA) from MRL Laboratories and PanBio, a rapid immunochromatographic test (RIT) from PanBio, immunofluorescence assays (IFA) from Progen, a dot blot assay from Genelabs, and a dipstick EIA from Integrated Diagnostics (INDX). For this study a panel of 132 serum samples, including 90 serum samples from patients with suspected dengue virus infection and 42 serum samples from patients with other viral infections, was used. In addition, serial serum samples from two monkeys experimentally immunized and challenged with dengue virus type 2 were used. Results were considered conclusive when concordant results were obtained with four of the six antibody-specific assays. Based on this definition, the calculated overall agreement for the human serum samples for the respective IgM immunoassays was 97% (128 of 132), with 34% (45 of 132) positive serum samples, 63% (83 of 132) negative samples, and 3% of samples (4 of 132) showing discordant results. The calculated overall agreement for the IgG assays was 94% (124 of 132), with 49% (65 of 132) positive, 45% (59 of 132) negative, and 6% (8 of 132) discordant results, respectively. The sensitivities of the dengue virus-specific assays evaluated varied between 71 and 100% for IgM and between 52 and 100% for IgG, with specificities of 86 to 96% and 81 to 100%, respectively. The relative sensitivities of the respective IgM assays measured with the monkey serum samples were comparable with those obtained with 12 serial serum samples from humans. Overall performance, based on the sum of the agreement, sensitivity, specificity, and Kappa statistics of the IgM and IgG immunoassays, showed that the antibody detection systems from INDX and Genelabs and the MRL and PanBio EIA are useful and reliable assays for dengue virus serodiagnosis. http://repub.eur.nl/res/pub/3689/ 1999-11-01T00:00:00Z The diagnostic value of dengue virus (DV)-specific immunoglobulin A (IgA) serum antibody detection, by an indirect immunofluorescence assay (IFA) was evaluated. For this study, the kinetics of DV-specific IgA serum antibodies was analysed in two experimentally immunised macaques, paired samples from 35 patients suspected of a primary or secondary DV infection, paired sera from patients with high levels of IgA specific antibodies against influenza virus (n = 15), sera from patients with other viral infections (n = 40) and healthy blood donors (n = 10), which served as controls. The presence of DV-specific IgA serum antibodies in humans and in monkeys was compared with that of DV-specific IgM demonstrated in a capture enzyme-linked immunosorbent assay (ELISA). The development of DV-specific IgA and IgM antibodies in macaques proved to be similar to that observed in humans with a DV infection. In sera obtained from suspected primary DV patients during the acute phase and convalescent phase, DV-specific IgA was detected in 1/6 (17%) and 6/6 (100%), whereas IgM was detected in 4/6 (67%) and 5/6 (83%), respectively. In sera from suspected secondary DV patients during the acute phase and convalescent phase, DV-specific IgA was detected in 18/29 (62%) and 28/29 (97%), whereas IgM was detected in 20/29 (69%) and 28/29 (97%), respectively. The control group consisted of five paired serum samples from yellow fever vaccinated individuals and a patient with acute tick-borne encephalitis, 15 paired serum samples from patients with high levels of IgA antibodies specific for influenza virus and 40 serum samples from patients with specific IgM antibodies against other viruses. Ten serum samples from healthy blood donors were included. Among the control serum samples, in one patient, both DV-specific IgA and IgM antibodies were present, and in three sera DV-specific IgM antibodies could be demonstrated. These data suggest that detection of DV-specific IgA serum antibodies by IFA may have additional value for the diagnosis of DV infection.