ThehCGELISAisanenzymeimmunoassayforthequantitativeinvitrodiagnosticmeasurementofintacthumanchorionicgonadotropin(hCG)inserumorplasma.
ChorionicGonadotropin(hCG)isaglycoproteinhormonewhichisnormallyproducedbytheplacentaduringpregnancy.Afterconception,thehCGconcentrationincreasesrapidlytoreachapeakneartheendofthefirsttrimester.Highconcentrationsareobservedthroughoutpregnancy.Afterdelivery,hCGlevelsfallrapidlyandbecomeundetectableafterafewdays.
StructurallyintacthCGmoleculesarecomposedofanalphaandabetasubunitwithamolucularweightof38.4kDa.Thealphasubunitisnearlyidenticaltothealphasubunitsofotherglycoproteinhormones,suchasThyroidStimulatingHormone(TSH),LuteinizingHormone(LH),andFollicleStimulatingHormone(FSH):Thedifferencesinthebetasubunitoftherespectivehormonesaccountfortheir
BIOLOGicalspecificityandimmunochemicaldistinctiveness.MonoclonalantibodiesrecognizinguniquesitesonthebetachainofthehCGmoleculeareessentialfordifferentiationbetweenhCGandLH,FSHandTSH.
hCGAssaysareusedfortheearlydetectionofpregnancy.
1.InadditiontotheelevatedhCGlevelsduringpregnancy,highconcentrationsofhCGmaybeassociatedwithneoplasmsoftrophoblasticandnontrophoblasticoriginsuchashydatiformmole,chorionepithelioma,embryonalcellcarcinoma,andmanyothers.
2.HCGiscommonlyelevatedindifferenttesticulartumorsandisthususedasatumor
MarkerfortesticulartumorsincombinationwithAFP.ThereisagoodcorrelationbetweenchangesinhCGlevelsandresponsetotherapy.
3.Extragonadalgerm-cellcancersintheabsenceofclinicallyorultrasonographicallydetectabletesticularabnormalitieshavebeeinobservedaswell.Over50%ofpatientswithmalignantinsulinomashaveelevatedhCGlevels:thehormoneisnotdetectedinassociationwithbenignadenomas.EctopicsecretionofhCGalsohavebeenfoundinasmallpercentageofpatientswithadenocarcinomaoftheovary,pancreasandstomach,hepatomas,andislet-cellcarcinomas.
ForconcretedatapleaseconsulttheInstructionforUseinthedownloadboxontherightside.