
Description:
Anti-Jo-1antibodyisamyositisspecificautoantibodymostcommonlyfoundinpatientsofPolymyositis(PM)andDermatomyositis(DM).PMandDMareidiopathicinflammatorymyopathies,characterizedbyproximalmuscleweakness,elevatedmuscleenzymeactivitiesandelectromyographicandhistologicalfeature.Thisantibodyisdirectedagainstthehistidyl-tRNAsynthetasewhichcatalysesthebindingofthehistidinetoitscognatetRNAduringproteinsynthesis.Anti-Jo-1antibodyispredominantlyfoundin20-30%ofPMpatientsand60-70%ofPMwithinterstitialpulmonaryfibrosis.TheantibodyisalsofoundinDM,althoughlessfrequentlythaninPM.,ItisrareinchildrenwithPMorDMandinotherconnectivetissuediseases.Moreover,theserumlevelsofanti-Jo-1antibodystronglycorrelatewithdiseaseactivityrepresentingagoodMarkerfordiseasemonitoring.Principle:
AutoimmuneELISAkitsmeasureautoimmuneantibodiesintheserum.Itisbasedontheprincipleofasolidphaseenzyme-linkedimmunosorbentassay.Theassayutilizesaspecificantigenforimmobilizationonthemicrotiterwellsandanti-humanIgGantibodyconjugatedtohorserADIshperoxidase(HRP)fordetection.Thetestsampleisallowedtoreactsimultaneouslywiththetwocomponents,resultingin autoimmuneantibodiesbeingsandwichedbetweenthesolidphaseandenzyme-linkedantibodies.Afterincubation,thewellsarewashedtoremoveunbound-labeledantibodies.AHRPsubstrate,TMB,isaddedtoresultinthedevelopmentofabluecolor.ThecolordevelopmentisthenstoppedwiththeadditionofStopSolutionchangingthecolortoyellow.Theconcentrationofautoimmuneantibodies isdirectlyproportionaltothecolorintensityofthetestsample.Absorbanceismeasuredspectrophotometricallyat450nm.