title: Determination of tumor necrosis factor-alpha levels in dengue virus infected patients by sensitive biotin-streptavidin enzyme-linked immunosorbent assay.
abstract: A modified sandwich enzyme-linked immunosorbent assay using biotin-streptavidin system (BS-ELISA) was developed to determine levels of tumor necrosis factor-alpha (TNF-alpha) in serum samples of children infected with dengue virus (n=99) and healthy controls (n=41). The minimum detectable concentration of TNF-alpha by the BS-ELISA was 3.3 pg/ml. The mean TNF-alpha 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-alpha in the sera of DF and DHF patients could be detected on days 2-6 after the onset of fever, the high level occurring on day 5. TNF-alpha 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-alpha than the sera of controls, P-value<0.001. DHF patients had significantly higher levels of TNF-alpha than DF patients (P-value=0.020) but no difference in the TNF-alpha 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-alpha in serum samples of DF and DHF patients. The TNF-alpha levels might be associated with dengue virus infection and related to disease severity of DHF.
authors.affiliation: Department of Microbiology, Faculty of Public Health, Mahidol University, Bangkok, Thailand. phlkt@mahidol.ac.th
authors.forename: L
authors.initials: L
authors.lastname: Kittigul
authors.forename: W
authors.initials: W
authors.lastname: Temprom
authors.forename: D
authors.initials: D
authors.lastname: Sujirarat
authors.forename: C
authors.initials: C
authors.lastname: Kittigul
mesh_terms: D000293:Adolescent; D001710:Biotin; D002648:Child; D002675:Child, Preschool; D003715:Dengue / Q000276:immunology* / Q000503:physiopathology / Q000821:virology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D011994:Recombinant Proteins; D012680:Sensitivity and Specificity; D019595:Severe Dengue / Q000276:immunology* / Q000503:physiopathology / Q000821:virology; D012720:Severity of Illness Index; D019809:Streptavidin; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis* / Q000235:genetics
chemical_list: D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D001710:Biotin; D019809:Streptavidin