SkipNavigationAdvertisementPeyer'sPatchesBy:TimTaylorLastUpdated:Dec13,2016Peyer’spatchesaresmallmassesoflymphatictissuefoundthroughouttheileumregionofthesmallintestine.Alsoknownasaggregatedlymphoidnodules,theyformanimportantpartoftheimmunesystembymonitoringintestinalbacteriapopulationsandpreventingthegrowthofpathogenicbacteriaintheintestines.Peyer’spatchesareroughlyegg-shapedlymphatictissuenodulesthataresimilartolymphnodesinstructure,exceptthattheyarenotsurroundedbyaconnectivetissuecapsule.Theybelongtoaclassofnon-encapsulatedlymphatictissueknownaslymphaticnodules,whichincludethetonsilsandlymphatictissueoftheappendix.ContinueScrollingToReadMoreBelow...AnatomyExplorerCysternaChyliIliacNodesInguinalNodesIntestinalTrunkLumbarTrunkLymphNodeOverviewPeyer'sPatchesSpleenThoracicDuct(LeftLymphaticDuct)«BackShowonMap»AnatomyTermDisplayedonotherpageJoinourNewsletterandreceiveourfreeebook:GuidetoMasteringtheStudyofAnatomyFirstNameEmail*SubscribeWehatespamasmuchasyoudo.Unsubscribeatanytime.ClickToViewLargeImageContinuedFromAbove...SpecialepithelialcellsknownasmicrofoldcellslinethesideofthePeyer’spatchfacingtheintestinallumen,whiletheoutersidecontainsmanylymphoidcellsandlymphaticvessels.ThefunctionofPeyer’spatchesistoanalyzeandrespondtopathogenicmicrobesintheileum.AntigensfrommicrobesinthegutareabsorbedviaendocytosisbymicrofoldcellsliningthesurfaceofeachPeyer’spatch.Theseantigensarepassedontothelymphoidtissue,wheretheyareabsorbedbymacrophagesandpresentedtoTlymphocytesandBlymphocytes.Whenpresentedwithdangerouspathogenicantigens,lymphocytestriggertheimmuneresponsebyproducingpathogen-specificantibodies;turningintopathogen-killingcytotoxicTlymphocytes;andmigratingthroughlymphaticvesselstolymphnodestoalerttheothercellsoftheimmunesystem.Thebodythenpreparesafullbody-wideimmuneresponsetothepathogenbeforeitisabletospreadbeyondtheintestines.Copyright©InnerbodyResearch1999-2021.AllRightsReserved.InnerbodyResearchdoesnotprovidemedicaladvice,diagnosis,ortreatment.Youmustconsultyourownmedical