JournalofVirologicalMethods90(2000)51–57Determinationoftumornecrosisfactor-alphalevelsindenguevirusinfectedpatientsbysensitivebiotin-streptavidinenzyme-linkedimmunosorbentassayL.Kittigula,*,W.Temproma,D.Sujiraratb,C.KittigulcaDepartmentofMicrobiology,FacultyofPublicHealth,MahidolUni�ersity,Bangkok,ThailandbDepartmentofEpidemiology,FacultyofPublicHealth,MahidolUni�ersity,Bangkok,ThailandcDepartmentofMicrobiology,FacultyofScience,KasetsartUni�ersity,Bangkok,ThailandReceived31March2000;receivedinrevisedform16June2000;accepted16June2000AbstractAmodifiedsandwichenzyme-linkedimmunosorbentassayusingbiotin-streptavidinsystem(BS-ELISA)wasdevelopedtodeterminelevelsoftumornecrosisfactor-alpha(TNF-�)inserumsamplesofchildreninfectedwithdenguevirus(n=99)andhealthycontrols(n=41).TheminimumdetectableconcentrationofTNF-�bytheBS-ELISAwas3.3pg/ml.ThemeanTNF-�levelwashighestinthosepatientswithdengueshocksyndrome(DSS)ordenguehemorrhagicfever(DHF)gradeIII(37.44�42.0pg/ml).LowerlevelswerefoundinDHFgradeI(28.44�42.7pg/ml),DHFgradeII(24.21�25.4pg/ml)anddenguefever(DF)(14.10�24.0pg/ml).TNF-�intheseraofDFandDHFpatientscouldbedetectedondays2–6aftertheonsetoffever,thehighleveloccuringonday5.TNF-�wasdetectedin41.4%(24.01�35.2pg/ml)ofdenguevirusinfectedpatientsand7.3%(4.2�15.6pg/ml)ofcontrolsubjects.TheseraofpatientscontainedsignificantlyhigherlevelsofTNF-�thantheseraofcontrols,P-value�0.001.DHFpatientshadsignificantlyhigherlevelsofTNF-�thanDFpatients(P-value=0.020)butnodifferenceintheTNF-�levelsfromseraofDHFgradesI–IIIpatientswasobserved(P-value=0.295).TheresultsindicatethattheBS-ELISAisaverysensitivemethodfordeterminingTNF-�inserumsamplesofDFandDHFpatients.TheTNF-�levelsmightbeassociatedwithdenguevirusinfectionandrelatedtodiseaseseverityofDHF.©2000PublishedbyElsevierScienceB.V.Keywords:Tumornecrosisfactor-alpha;Denguehemorrhagicfever;Denguefever;Biotin-streptavidinELISAwww.elsevier.com/locate/jviromet1.IntroductionDenguevirusinfectionisacommondiseasewhichoccurrsworldw...
