简介:Wehavepreviouslydemonstratedtheabilityofmalariaparasitestointerferewithspecificimmuneresponses.CD4Tcellsspecifictoparasiteantigens,butnotCD4Tcellsspecifictoanirrelevantantigen,ovalbumin(OVA),aredeletedviaapoptosisduringmalariainfection.Itisofinterest,therefore,toinvestigatetheimmuneresponsesthatdevelopedfollowingvaccinationwiththe19kDacarboxylterminusofthemerozoitesurfaceprotein1(MSP119)inmicethathadpreviouslyexperiencedmalariainfection.Inthisstudy,pre-exposureofmicetoPlasmodiumyoeliielicitednativeanti-MSP119antibodyresponses,whichcouldbeboostedbyvaccinationwithrecombinantMSP119,Likewise,infectionofMSP119-primedmicewithPlasmodiumyoelii(P.yoelii)ledtoanincreaseofanti-MSP119antibodies.MSP119vaccinationofmalariapreexposedmiceorimmunizationbyinfection/cureofMSP119-primedmiceenabledthemicetosurvivechallengeinfection,withtheformergrouphavingslightlylowerparasitaemia.Thedatasuggestthatexposuretomalariainfectionprimesanaturalimmuneresponsewhichcanbeboostedbyvaccination.Thisinformationisrelevanttothedevelopmentofavaccineforuseinindividualslivinginmalaria-endemicareas.
简介:Toinvestigatethematernal-infantileinfectionwithhumanparvovirusB19,theIgGandIgMantibodiesagainsthumanparvovirusandtheB19-DNAinserumandperipheralbloodmononuclearcells(PBMC)ofpregnantwomenaswellastheserumIgMantibodyagainstB19andtheB19-DNAinserumandcordbloodnucleatedcells(CBNC)ofnewbornsweredeterminedbyELISAandnestedPCRrespectively.ItwasfoundthatthepositiverateoftheIgGantibodyagainsthumanparvovirusB19inseraof92pregnantwomenwas38.04%(35/92),andthatoftheIgMantibodyin720pregnantwomenwas9.03%(65/720).However,theIgMantibodyagainsthumanparvovirasB19wasnegativeinthecordbloodseraof95newborns.AstothehumanparvovirasB19DNA,noneof720pregnantwomenand95newbornswasprovedtobepositiveintheirsera,Nevertheless,thepositiverateoftheparvovirasB19DNAinPBMCwas3.06%(3/98)in98pregnantwomenand1.12%(1/89)inCBNCof89newborns.ItisconcludedthatthehistoryofinfectionwithhumanparvovirasB19existsincertainpregnantwomenwithasmallpercentageofpregnantwomeninfectedwithrecentoracuteinfectionsofB19virus.ThedetectionratesoftheB19viralDNAinPBMCofpregnantwomenandCBNCofnewbornswerehigherthanthoseinsera,indicatingthattheriskforverticaltransmissionisverylow.