EnzymeimmunoassayforthequalitativedeterminationofIgAclassantibodiesagainstCandidaalbicansinhumanserumorplasma(citrate).Candidaalbicansisanubiquitiouspresentyeastlikefungusbelongingtothefamilyofascomycota.Itisafacultativepathogenbelongingtothenormalmicrobialfloraofskinandmucosa.Besidetheyeastformwhichappearsmainlywithsuperficialinfections,socalledpseudomyceliaareanothermorphologicalformofascomycota.Pseudomyceliaprevailwithinvasivemycosis.AlthoughnotpathogenicinhealthyhumansthefungusmaybeopportuNISTicinthosesufferingfromavarietyofdisorders,andinthosetreatedintensivelywithbroad-spectrumantibioticsorimmunosuppressivemeasures.Candidiasisiscausedtoabout90%byC.albicans.Itisanacute,superficialorsubacute,invasiveinfection.Acuteinfectionswiththefungusmayproducelesionsinthemouth,vagina,skinandnails.Subacuteinfectionsmayaffectbronchi,lungs,heartormeningeal.Inimmunosuppressantpatientswithcellularimmunodeficiency,e.g.,AIDSpatients,C.albicansmayleadtoseverenecrosesofinfectedtissues.ThequalitativeimmunoenzymaticdeterminationofIgA-classantibodiesagainstCandidaalbicansisbasedontheELISA(Enzyme-linkedImmunosorbentAssay)technique.MicrotiterstripwellsareprecoatedwithCandidaalbicansantigenstobindcorrespondingantibodiesofthespecimen.AfterwashingthewellstoremoveallunboundsamplematerialhorserADIshperoxidase(HRP)labelledanti-humanIgAconjugateisadded.ThisconjugatebindstothecapturedCandidaalbicans-specificantibodies.TheimmunecomplexformedbytheboundconjugateisvisualizedbyaddingTetramethylbenzidine(TMB)substratewhichgivesabluereactionproduct.TheintensityofthisproductisproportionaltotheamountofCandidaalbicans-specificIgAantibodiesinthespecimen.Sulphuricacidisaddedtostopthereaction.Thisproducesayellowendpointcolour.Absorbanceat450nmisreadusinganELISAmicrowellplatereader.