简介：TocloneandexpresstherecombinantoutermembraneproteinTp0453ofTreponemapallidumandtoanalyzetheimmuno-reactivityandimmunogenicityoftheexpressedprotein,theimmuno-dominantepitopeoftheTp0453wasamplifiedfromthecompletegenomeofT.pallidumbyPCR,subclonedintoexpressionvectorpQE32togeneratetherecombinantplasmidpQE32/Tp0453,thenexpressedinE.coliM15andanalyzedbySDS/PAGEandWesternblotting.ThefusionproteinexpressedwaspurifiedwithNi-NTAaffinitychromatography.Itsimmuno-reactivitywasassayedbyindirectELISA,andtheimmunogenicitywasdeterminedbyimmunizationwiththisfusionproteininNewZealandrabbits.Inthepresentstudy,afusionproteinofmolecularweightabout32kDawasobtained.AsdemonstratedbyWesternblotting,therecombinantproteincouldreactspecificallywithpositiveIgGseraofpatientswithsyphilis,andtheantibodiesagainstT.palliduminhumanseraweresuccessfullydetectedbyindirectELISA.BoththesensitivityandspecificityofELISAbasedontheTp0453fusionproteinaswere100%(30/30)whendetectedwithcontrolsera.IncomparisonwiththeresultsofIgGELISAwiththoseofTPPA.ItwasfoundthatthesensitivityofELISAwas96.8%andthespecificitywas100%.ThedifferenceofELISAandTPPAwasnotsignificant,andtheconcordanceofresultsbetweenELISAandTPPAwas98.2%.Inaddition,specifichumoralresponsescouldbeelicitedbyimmunizationwiththerecombinantfusionproteininNewZealandrabbitswithaspecificantibodytiterof1:1280after3successivedosesofimmunization.Theseresultsdemonstratethattheexpressedrecombinantfusionproteinshowsexcellentimmuno-competenceandprovidefoundationtodevelopaquickdiagnostickidappliedtodetectthepresenceofT.palliduminfections.