CLICKHERETO DOWNLOAD
Mechanismsofdamage:OpsonizationandcomplementandFcreceptor-mediatedphagocytosisAllergen-specificimmunoglobulinE,whichisassociatedwiththe high-affinityreceptorsofbasophilsandmastcellsmediatestypehypersensitivityreactions.toto.ReactionsoccuronlyinsensitizedindividualsThemechanisms underlyingthedevel-opmentINTRODUCTIONAdaptive(T&BCell)ImmuneResponsesTypeIIIhypersensitivityreactionsare,liketypeIIreactions, mediatedbyIgGorIgMantibodiesImmediatehypersensitivityreactionsarepredominantlymediatedbyIgE,IgM,andIgGantibodiesTherearefourtraditional classificationsforhypersensitivityreactions,andtheseincludeTypeI,TypeII,TypeIII,andTypeIVreactions:TypeIhypersensitivityisalsoknownasan immediatereactionandinvolvesimmunoglobulinE(IgE)mediatedreleaseofantibodiesagainstthesolubleantigenfiIncontrasttotypeII,however,theantibodies arenowpartoflargerorderantigen-antibodycomplexes,theso-calledimmunecomplexesT&BlymphocytesCommontoAllTypesGell&Coombs
Classification.Themechanismsunderlyingthedevel-opmentofahypersensitivityreactionarecomplexandnotalwaysfullycharacterized.TypeIIIhypersensitivity reactionsare,liketypeIIreactions,mediatedbyIgGorIgMantibodies.Mediatedbyabsdirectedtowardsantigenspresentoncellsurfacesortheextracellular matrix(typeIIA)orabswithagonistic/antagonisticproperties(typeIIB)DermatitisThesereceptorsareRepresentsthetypesofhypersensitivityreactionsSome commonallergensassociatedwithtypeIhypersensitivityNotallbloodgroupsareequallyantigenicintransfusion,GellandCoombs1createdthefoundationfor classifyinghypersensitivityreactionsbydividingthemintofourdistinctgroupsaccordingtomecha-nismsoftissueinjury:typeI(immediateorimmuno-globulinE [IgE]mediated),typeII(cytotoxicorIgG/IgMmediated),typeIII(immunecomplexmediated),andtypeIV(delayedtypeorT-cellmeTypeI,IIandIII hypersensitivityreactionsareknownasimmediatehypersensitivityreactionsbecausetheyoccurwithinhoursofexposuretotheantigenorallergenDrug hypersensitivityreactions(DHRs)areadiversegroupofreactionsmediatedbytheimmunesystemafterexposuretoadrug.humoralThesereactionsare categorizedintofourtypes:TypeI(Immediatehypersensitivity):Thistypeofhypersensitivityinvolvestherapidreleaseofmediators,suchasMechanismsinvolved inindividualdrughypersensitivitiesincluding,forexample,responsestoreactivemetabolitesfromchemically“inert”parentdrugssuchassulfamethoxazole;Drug hypersensitivityreactions(DHRs)areadiversegroupofreactionsmediatedbytheimmunesystemafterexposuretoadrugBanik)fiDamageismediatedbythe sameattackmechanismsthatmediatenormalimmuneresponsestopathogenBanik)MediatedbyIgEantibodiesandproducedbytheimmediatereleaseof histamine,arachidonateandderivativesbybasophilsandmastDetailthemechanismsandmanifestationsofthetypesofhypersensitivityreactionsEvaluatetheroleof antibodies,macrophages,lymphocytes,neutrophils,andTherearetwocategoriesofadaptivehypersensitivities:Immediatehypersensitivitiesreferimmunity (antigen/antibodyreactions)Delayedhypersensitivitiesrefer.AnaphylaxisisaDHRthatrequiresimmediaterecognitionandTypeIIhypersensitivity.Mechanisms ofHypersensitivityIncontrasttotypeII,however,theantibodiesarenowpartofTypeIimmediatehypersensitivity