L. KittigulW. TempromD. SujiraratC. KittigulMahidol UniversityKasetsart University2018-09-072018-09-072000-10-01Journal of Virological Methods. Vol.90, No.1 (2000), 51-57016609342-s2.0-0033817321https://repository.li.mahidol.ac.th/handle/123456789/25969A modified sandwich enzyme-linked immunosorbent assay using biotin-streptavidin system (BS-ELISA) was developed to determine levels of tumor necrosis factor-alpha (TNF-α) in serum samples of children infected with dengue virus (n=99) and healthy controls (n=41). The minimum detectable concentration of TNF-α by the BS-ELISA was 3.3 pg/ml. The mean TNF-α level was highest in those patients with dengue shock syndrome (DSS) or dengue hemorrhagic fever (DHF) grade III (37.44±42.0 pg/ml). Lower levels were found in DHF grade I (28.44±42.7 pg/ml), DHF grade II (24.21±25.4 pg/ml) and dengue fever (DF) (14.10±24.0 pg/ml). TNF-α in the sera of DF and DHF patients could be detected on days 2-6 after the onset of fever, the high level occuring on day 5. TNF-α was detected in 41.4% (24.01±35.2 pg/ml) of dengue virus infected patients and 7.3% (4.2±15.6 pg/ml) of control subjects. The sera of patients contained significantly higher levels of TNF-α than the sera of controls, P-value<0.001. DHF patients had significantly higher levels of TNF-α than DF patients (P-value=0.020) but no difference in the TNF-α levels from sera of DHF grades I-III patients was observed (P-value=0.295). The results indicate that the BS-ELISA is a very sensitive method for determining TNF-α in serum samples of DF and DHF patients. The TNF-α levels might be associated with dengue virus infection and related to disease severity of DHF. Copyright (C) 2000 Elsevier Science B.V.Mahidol UniversityImmunology and MicrobiologyArticleSCOPUS10.1016/S0166-0934(00)00215-9