細胞小知識 - 長春藤生命科學

免疫細胞是什麼？保護人體不被病菌侵擾 · 巨噬細胞(Macrophage)：白血球中最大的細胞，約占總血球5%，能像變形蟲般蠕動，將異物吞噬分解。

· 淋巴球(Lymphocyte)：接收由巨噬 ...  CellFYIWhatareimmunecells?Protectthehumanbodyfrombeinginfestedbygerms Specificimmunecells:Tcells,Bcells Immunecellsarethegeneraltermforcellsthatparticipateintheimmuneresponseinthehumanbody.Whenthebodyisinvadedbyvirusesorbacteria,immunecellscanrecognizeantigens,andtheninitiatethebody'simmuneresponsetoprotectthebodyfromillness.Immunecellscanbedividedintothreetypes:specificimmunecells,non-specificimmunecellsandantigenpresentingcells.   SpecificimmunecellsincludeTcellsandBcells,whichhaveamemoryfunctionintheimmuneresponse,canrememberdifferentantigens,andmakeatargetedimmuneresponseagainsttheantigen.   Non-specificimmunecells:NKcells,macrophages,neutrophils,mastcells Non-specificimmunecellsarethefirstlineofdefenseofthehumanimmunesystem.Theycanidentifymultipleantigensanddestroyinvadingbacteria,buttheycannotmakespecificimmuneresponsesagainstdifferentantigens.Macrophages,neutrophils,NKcells,mastcells,etc.areallnon-specificimmunecells.   Antigenpresentingcells:dendriticcells,macrophages,Bcells Helpcapturetheantigeninthehumanbody,presenttheantigentoTcells,andstrengthentheabilityofTcellstorecognizeantigens.Dendriticcells,macrophagesandBcellscanallplaytheroleofantigenpresentation.Simplyput,immunityisthebody'sdefensemechanism.Whenthehumanbodyencounters"foreignbody"invasion,ifitisallowedtoproliferateinlargenumbers,itwillcausedisease.Whitebloodcellsusuallypatrolthebodytomonitoranysubtlereactions.Onceaforeignbodyinvades,theimmunesystemwillsendout"soldiers"toquicklycollectintelligence,organize"armies"toresistforeignenemies,andeliminatethemwhennecessary.Inotherwords,soldiersmusthavetheabilitytodistinguishbetween"self"and"non-self."Thisisthewonderoftheimmunesystem.Aslongasdiscernmentandresistancecanwork,peoplewillnotgetsick.Therefore,oncetheimmunityisreduced,variousdiseaseswilleasilyfollow. ​Whitebloodcellsplayaroleinmonitoringforeignbodiesinthebodyandkillinggermsandcancercellsinthehumanbody.Whichisdividedinto: ​ Macrophage(macrophage):Thelargestcellinwhitebloodcells,accountingforabout5%ofthetotalbloodcells,canwrigglelikeanamoebatoswallowanddecomposeforeignbodies. ​ Lymphocytes:Receivingcommandsfrommacrophages,somecellsreleaseadhesivemoleculestofightforeignbodiesandproduceantibodies. ​ Granulocytes:Aftertheforeignbodyiswrappedinamembrane,itisdigestedanddecomposedbyenzymesandactiveoxygentostrengthenthepowerofmacrophagestoswallowtheforeignbody. ​ ​ Firstofall,macrophageswillmeasurethesizeoftheforeignbody.Iftheforeignbodyistoosmalltobeswallowedbythepellet,themacrophagewillissueanattackcommandtothelymphocyte.Afterthelymphocytefindsaforeignbody,itreleasesadhesivemoleculestocaptureandprocesstheforeignbody.Somelymphocyteswilllabelforeignbodiesas"antigens",andthelymphocytescanbeprocessedfirstwhenthesameantigeninvadesnexttime.Lymphocytesalsoinclude:Tcells,BcellsandNKcells. Tcells:playtheroleofcommander-in-chief,responsibleforreceivingandsendingcombatmessages,accountingfor70-80%ofperipheralbloodlymph; Bcells:Speciallyproduceantibodiestodealwithforeignbodiesinthebody,accountingforabout5-10%; NKcells:non-specificcytotoxicity,accountingforabout15-20%.Backtotop