IMMUNOLOGICfANDfINFECTIOUSfDISORDERS
DefinitionfoffTerms:
1. Antigen:fanfagentfcapablefoffproducingfAb
2. Antibody:fanfimmunoglobulinfwhichfreactsfwithfafspecificfAgfthatfinducefitsfsynthesis
3. Antiserum:fserumfcontainingfAbfgivenftofprovidefimmunityfagainstfafspecificfdse
fffff:f(passive)f temporaryf protectionf [example:f antitetanus fserumf(ATS)]
4. Antitoxin:fanfAbfthatfneutralizesfbacterialftoxinf[passivefimmunity]
5. Endemic:foccursfhabituallyfwithinfafgivenfgeographicalflocation/area
:fdsefoccursfatfafconstantfratefaffectingfaboutfthefsamef#foffpeoplefoverfa
ffffffgivenf time
• Example:fMalariafinfPalawan,fSchistosomiasisfinfBicol,fSamar,fLeytef&fDavao
• “belonging”,f“nativefto”,f“characteristicfof”
6. Epidemic:fafdefinitefincreasefoverfitsfexpectedfendemicfpatternsf(“outbreak”finfoneflocale)
:fdsefattacksfmanyfpeoplefinfafgivenfcommunityfsimultaneouslyf
• Example:fSARSfinfChina
7. Sporadic:foccasional,firregularfappearancefoffcasesfinfafpopulationfoverfafgivenfperiodfof
fftime
:foccursfsinglyfandfwidelyfscattered,fpatternless
• Example:fRabies
8. Pandemic:fextensivefepidemicfoccurringfoverfaflargefareaf(global)
• Example:fAIDS
9. Exanthem:feruptionsfonfthefskin
10. Enanthem:feruptionsfonfthefmucousfmembranes
11. Toxin:fpoisonousfsubstancefproducedfbyfbacterialfaction
12. Toxoid:fafmodifiedftoxinfcapablefoffstimulatingfthefproductionfoffAbf(ex:fTT)
13. Vaccine:fafsuspensionfoffattenuatedfmicroorganismsfgivenftofbuildfupfactivefimmunity
againstfinfectiousfdsesf(ex:fOPV,fDPT,fBCG)
14. Endotoxin:fafpoisonfretainedfwithinfthefbodyf&fisfreleasedfwhenftheforganismsfhas
ffff disintegrated/lysed
15. Exotoxin:fsolubleftoxinfthatfemergesfintofthefbody/outsidefthefbody
16. Quarantine:flimitationfofftheffreedomfoffmovementfoffmanf&fanimalsfexposedfto
fffffcommunicablef dse
17. Isolation:fseparatingfpersonsfhavingfcommunicablefdseffromfthefgeneralfpublic
fffffffffff:fseparatingf infectiousf pxffromf otherf individuals
18. Contamination:fmerefpresencefoffanfinfectiousfmaterial
19. Infection:fimplantationf&fsuccessfulfreproductionfoffanfinfectiousfagentfinfaflivingfhost
20. Symbiosis:fbenefitsfonlyfthefhumanf&ftherefisfnofharmftoftheforganism
21. Mutualism:fbenefitsfbothfhumanf&forganism
22. Commensalism:fbenefitsfonlyftheforganismf&fnofharmftofthefhuman
23. Opportunism:fwhenfbenignforganismsfbecomefpathogenicf(ex:fsuperinfection,fAIDS)
24. Pathogenicity:frelationshipfthatfharmsfthefhumanf&fbenefitsftheforganism
fffffff:f abilityf tof causef dsef (ex:f parasitism;f infxn)
25. Bacteremia:fbacteriafentersfbloodstreamfbutfdoesfnotfmultiply
26. Septicemia:fbacterialfmultipliesfcausingfinfxn
27. Immunity:fisfthefresultfoffAb-Agfrxnforfthefresistancefthatfafpersonfhasfagainstfafdse
TypesfoffInfxn
A.fSourcefoffAgent
28. ExogenousfInfxn:fcausativefagentfreachfthefbodyffromfthefoutside
29. EndogenousfInfxn:fcausativefagentfisfnormallyfpresentfinfthefbody
B.fLocation
30. LocalizedfInfxn:fremainsfconfinedftofafparticularfarea
31. GeneralizedfInfxn:finfectionfspreadsfoverfthefbodyfthroughfthefbloodforflymphaticfsystem
,C.fOthers
32. MixedfInfxn:ftwoforfmoreforganismsfcausefthefdse
33. Subclinical/inapparent:finfxnsfthatfdoesfnotfcausefdetectablefmanifestationsf(ex:fSTD)
34. Latent:finfxnfisfcontrolledfbyfdefensivefpowersfbutfactivatedf(ex:fPTB)
35. CommunicablefDisease:fdsefcapablefoffbeingftransmittedffromfonefpersonftofanother
Immunity
>fafstatefoffhavingfsufficientfbiologicalfdefensesftofavoidfinfxn,fdse,forfotherfunwantedfbiologicalfinvas
ion
>fderivedffromf“immunis”f–
f Latinfmeaningf “exemptionffromfmilitaryf service,f taxf paymentsf &f otherf publicf services”
2fGeneralfTypes:
1. Innate:fnonspecific;fpresentfatfbirth
:fresponseftofafforeignfinvaderfisfveryfsimilarffromfonefencounterftofthefnext
ffregardlessf off thef #f off timesf thef invaderf wasf encountered
• 2fStages
o Immediate:foccursfwithinf4fhours
o Delayed:fbetweenf4-96fhrsfafterfexposure
• Classes
I. WhitefBloodfCellfAxn
II. InflammatoryfResponse
III. Physicalf&fChemicalfbarriers
IV. Immunefregulation:fidentifyfAgfasf“non-self”;fprodxnfoffcytokines
2. Acquiredf(Adaptive):fspecific;fdevelopsfafterfbirth
ffffffff:fresponsef tof afforeignf invaderf thatf increasesf inf intensityf with
ffffffffffrepeatedf exposuref tof thef invadingf agent
• 2fTypes
o Natural:foccursfthrufcontactfwithfagent
o Artificial:fdevelopsfonlyfthrufdeliberatefaxns
• 2fSubtypes:finvolvefhumoralf&fcellularfimmunologicfresponses
o Active:fimmunologicfdefensesfdevelopedfbyfthefperson’sfownfbody
ffff:f lastsfforfmanyf yrsf orf evenf af lifetimef(ex:fvaccines)
o Passive:ftemporaryfimmunityftransmittedffromfafsourcefoutsidefthefbody
fffffffffthatf hasf developedf immunityf thruf previousf dsef orf immunization
(ex:fimmunefglobulins/antiserum;ftransferfoffAbffromfmotherfinfuteroforfthrufBF)
fLouisfPasteur:fGERM fTHEORYfoffDse:ftalksf aboutf howf bacteriaf causedf dse
a. NaturalfPassive:fimmunityfacquiredffromfmaternalfAb
b. NaturalfActive:fimmunityfacquiredfafterfanfinfxn
c. ArtificialfPassive:fantibodyftransferf
d. ArtificialfActive:facquiredffromfimmunization
IMMUNEfSYSTEM
➢ afcomplexf&fintricatefnetworkfoffspecializedfcells,ftissuesf&forgans
➢ cellsfoffthefimmunefsystemfseekfoutf&fdestroyfdamagedfcellsf&fforeignftissue,fyetfrecognizef
&fpreservefhostfcells
➢ FUNCTIONS:
a. Defendingf&fprotectingfthefbodyffromfinfxnfbyfbacteria,fviruses,ffungif&fparasites
b. Removingf&fdestroyingfdamagedforfdeadfcells
c. Identifyingf&fdestroyingfmalignantfcells,ftherebyfpreventingftheirffurtherfdevtfintoftu
mors
➢ Activatedfbyfminorfinjuriesfsuchfasfsmallflacerationsforfbruises,forfbyfmajorfinjuriesfsuchfasfb
urns,fsurgeriesf&fsystemicfdses
➢ Responsefoffthefimmunefsystemfmayfbefnonspecificforfspecific
,Components
1. LEUKOCYTESf(4,500-10,000fcells/mm3)
➢ WBCsfarefthefprimaryfcellsfinvolvedfinfbothfnonspecificf&fspecificfimmunefsystemfresponses
➢ Mobilefunitsfoffthefimmunefsystemfthatfdetect,fattackf&fdestroyfanythingfthatfisfrecognizedfasffo
reign
➢ Ableftofmovefthruftissuefspaces,flocatingfdamagedftissuesf&finfxnfbyfrespondingftofthefchemic
alsfreleasedfbyfotherfleukocytesforfdamagedftissuef–fCHEMOTAXIS
➢ Dividedfintof3fmajorfgroups:fgranulocytes,fmonocytesf&flumphocytes
a. Granulocytesf(60-80%)
• Havefafshortflifespan,fmeasuredfinfhrsftofdays
• Playfafkeyfrolefinfprotectingfthefbodyffromfharmfulfmicroorganismsfduringfacutefinf
lammationf&finfxn
• 3ftypes:fneutrophils,fbasophils,feosinophils
➢ Neutrophilsf(55-70%)
• alsofcalledfpolymorphonuclearfleukocytesf(PMNs/polys)
• mostfplentiful
• arefphagocyticfcellsfresponsiblefforfengulfingf&fdestroyingfforeignfagents,fparticul
arlyfbacteriaf&fsmallfparticles
• 1stfpagocyticfcellsftofarrivefatfthefsitefoffinvasion,fdrawnfbyfchemicalsfreleasedfbyfd
amagedftsef&finvadingforganismsf(chemotaxis)
• Segmentedforfsegsf(maturefform),fbandsf(immature)
➢ Eosinophilsf(1-4%)
• arefalsofphagocyticfcellsfbutfareflessfefficientfatfthisfprocessfthanfneutrophils
• foundfinflargef#sfinfthefrespif&fGIftracts
• thoughtftofprotectfbodyffromfparasiticfworms
• thesefcellsfsurroundfthefparasitef&freleaseftoxicfenzymesffromftheirfcytoplasmicfgr
anules
• alsofinvolvedfinfthefhypersensitivityfresponse
➢ Basophilsf(0.5-1%)
• arefnotfphagocytic
• granulesfcontainfproteinsf&fchemicalsfsuchfasfheparin,fhistamine,fbradykinin,fser
otonin,f&fslow-reactingfsubstancesfoffanaphylaxisf(Leukotrienes)
• thesefsubstancesfarefrelasedfintofthefbloodstreamfduringfanfacutefhypersensitivit
yfrxnforfstressfresponse
b. Monocytesf(2-3%)f&fMacrophages
• theflargestfoffthefleukocytes
• migrateftofvariousftissuesfthroughoutfthefbody,fattachingfthemselvesftoftheftissue,f
whereftheyfremainfforfmonths/yrsfuntilftheyfarefactivated
• maturefintofmacrophagesfafterfsettlingfintoftheftissuesf&farefdifferentiatedfbyfthefti
ssuefinfwhichftheyfreside:
➢ histiocytesf–floosefconnectiveftissue
➢ Kupfferfcellsf–fliver
➢ Alveolarfmacrophagesf–flungs
➢ Microgliaf–fbrain
• alsoffoundfinfthefspleen,ftonsils,flymphfnodesf&fbonefmarrow
• activelyfphagocyticfwhichfthefcapacityftofphagocytizeflargefforeignfparticlesf&fcellf
debris
• likefneutrophils,fmacrophagesfarefdrawnftofanfinflamedfareafbyfchemicalsfrelease
dffromfdamagedftissues
• importantfinfthefbody’sfdefensefagainstfchronicfinfxnsfsuchfasfTB,fviralfinfxnsf&fcer
tainfintracellularfparasiticfinfxns
c. Lymphocytesf(20-40%)
, • principalfeffectorf&fregulatorfcellsfoffspecificfimmunefresponse
• protectfthefbodyffromfmicroorganisms,fforeignftissuef&fcellfmutationsforfalteration
s
• immunefsurveillance:flymphocytesfmonitorfthefbodyfforfcancerousfcellsf&feliminat
eforfdestroyfthem
• constantlyfcirculatefthenfreturnftofconcentratefinflymphoidftissuesf(lymphfnodes,fs
pleen,fthymus,ftonsils,fPeyer’sfpatchesf&fappendix)
• 3ftypes:fTflymphocytesf(T-cells),fBflymphocytesf(B-
cells)f&fnaturalfkillerfcellsf(NKforfnullfceslls)
LYMPHOIDfSYSTEM
➢ consistsfofftheflymphfnodes,fspleen,fthymus,ftonsils,flymphoidftissuefscatteredfinfconnectivef
tissuesf&fmucosa,fandfthefbonefmarrow
➢ centralf&fperipheralflymphoidforgans
• LymphfNodes
o arefsmall,froundforfbean-
shapedfencapsulatedfbodiesfthatfvaryfinfsizef&farefdistributedfthroughoutfthefbody
o 2ffunctions
▪ Filterfforeignfproductsforfantigensffromftheflymph
▪ Housef&fsupportfproliferationfofflymphocytesf&fmacrophages
• ThymusfGland
o locatedfinfthefsuperior,fanteriorfmediastinalfcavityfbeneathfthefsternum
o reachesfmaximumfsizefatfpubertyfthenfbeginsftofatrophy
o byfadulthood,fitfisfdifficultftofdifferentiateffromfsurroundingfadiposeftissuefevenfthoug
hfitfremainsfactive
o infthefelderly,fthefvastfmajorityfoffthefthymusftissuefhasfbeenfreplacedfbyfadiposef&ffi
brousfconnectiveftissue
o duringffetalflifef&fchildhood,fthefthymusfservesfasfafsitefforfthefmaturationf&fdifferenti
ationfoffTfcells
o Thymosin,fanfimmunoregulatoryfhormonefoffthefthymus,fstimulatesflymphopoiesis
• ComplementfSystem
o Consistsfoffapproxf20fcomplexfplasmafCHONsfthatfarefactivatedfbyfaftissuefinjuryforf
Ag-Abfrxn
o Involvedfinfbothfnonspecificf&fspecificfimmunefresponses
o Resultsfinfthefproductionfoffeffectorfmoleculesfthatfarefinvolvedfinfthefprocessfoffinfla
mmation,fphagocytosisf&fcellflysisforfdestruction
f A.fNONSPECIFICfINFLAMMATORY/IMMUNEfRESPONSE
▪ barrierfprotectionfisfthefbody’sf1stflinefoffdefensefagainstfinfxn
▪ skinfasfthefprimaryfbarrier
▪ mucousfbarrierfwhichftrapfmicroorganismsf&fotherfforeignfsubstancesfprotectsfmembrane
sfliningfinnerfsurfacesfoffthefbodyf
▪ ciliaryfmovt
▪ washingfaxnfofftearsforfurine
▪ bactericidalfsubstancesffoundfinfbodyffluidsfsuchfasfgastricffluid,fzincfinfprostaticffluidf&flys
ozymefinftears,fnasalfsecresions,fsalivaf&fsweat
▪ whenf1stflinefoffdefensesfarefbreached,fresultingftissuefdamageforfforeignfmaterialfenterin
gfthefbodyfinducesfafnonspecificfimmunefresponsefisfknownfasfinflammation
▪ Inflammation:fanfadaptivefresponseftofinjuryfthatfbringsffluid,fdissolvedfsubstancesf&fblo
odfcellsfintofthefinterstitialftissuesfwherefthefinvasionforfdamagefhasfoccurredfthereby,fthefi
nvaderfisfneutralizedf&feliminated,fdestroyedftissuefremovedf&fthefprocessfoffhealingfandfr
epairfinitiated
▪ 3fstages:fVascularfResponse,fCellularfResponsef&fTissuefRepair
1. VascularfResponse
DefinitionfoffTerms:
1. Antigen:fanfagentfcapablefoffproducingfAb
2. Antibody:fanfimmunoglobulinfwhichfreactsfwithfafspecificfAgfthatfinducefitsfsynthesis
3. Antiserum:fserumfcontainingfAbfgivenftofprovidefimmunityfagainstfafspecificfdse
fffff:f(passive)f temporaryf protectionf [example:f antitetanus fserumf(ATS)]
4. Antitoxin:fanfAbfthatfneutralizesfbacterialftoxinf[passivefimmunity]
5. Endemic:foccursfhabituallyfwithinfafgivenfgeographicalflocation/area
:fdsefoccursfatfafconstantfratefaffectingfaboutfthefsamef#foffpeoplefoverfa
ffffffgivenf time
• Example:fMalariafinfPalawan,fSchistosomiasisfinfBicol,fSamar,fLeytef&fDavao
• “belonging”,f“nativefto”,f“characteristicfof”
6. Epidemic:fafdefinitefincreasefoverfitsfexpectedfendemicfpatternsf(“outbreak”finfoneflocale)
:fdsefattacksfmanyfpeoplefinfafgivenfcommunityfsimultaneouslyf
• Example:fSARSfinfChina
7. Sporadic:foccasional,firregularfappearancefoffcasesfinfafpopulationfoverfafgivenfperiodfof
fftime
:foccursfsinglyfandfwidelyfscattered,fpatternless
• Example:fRabies
8. Pandemic:fextensivefepidemicfoccurringfoverfaflargefareaf(global)
• Example:fAIDS
9. Exanthem:feruptionsfonfthefskin
10. Enanthem:feruptionsfonfthefmucousfmembranes
11. Toxin:fpoisonousfsubstancefproducedfbyfbacterialfaction
12. Toxoid:fafmodifiedftoxinfcapablefoffstimulatingfthefproductionfoffAbf(ex:fTT)
13. Vaccine:fafsuspensionfoffattenuatedfmicroorganismsfgivenftofbuildfupfactivefimmunity
againstfinfectiousfdsesf(ex:fOPV,fDPT,fBCG)
14. Endotoxin:fafpoisonfretainedfwithinfthefbodyf&fisfreleasedfwhenftheforganismsfhas
ffff disintegrated/lysed
15. Exotoxin:fsolubleftoxinfthatfemergesfintofthefbody/outsidefthefbody
16. Quarantine:flimitationfofftheffreedomfoffmovementfoffmanf&fanimalsfexposedfto
fffffcommunicablef dse
17. Isolation:fseparatingfpersonsfhavingfcommunicablefdseffromfthefgeneralfpublic
fffffffffff:fseparatingf infectiousf pxffromf otherf individuals
18. Contamination:fmerefpresencefoffanfinfectiousfmaterial
19. Infection:fimplantationf&fsuccessfulfreproductionfoffanfinfectiousfagentfinfaflivingfhost
20. Symbiosis:fbenefitsfonlyfthefhumanf&ftherefisfnofharmftoftheforganism
21. Mutualism:fbenefitsfbothfhumanf&forganism
22. Commensalism:fbenefitsfonlyftheforganismf&fnofharmftofthefhuman
23. Opportunism:fwhenfbenignforganismsfbecomefpathogenicf(ex:fsuperinfection,fAIDS)
24. Pathogenicity:frelationshipfthatfharmsfthefhumanf&fbenefitsftheforganism
fffffff:f abilityf tof causef dsef (ex:f parasitism;f infxn)
25. Bacteremia:fbacteriafentersfbloodstreamfbutfdoesfnotfmultiply
26. Septicemia:fbacterialfmultipliesfcausingfinfxn
27. Immunity:fisfthefresultfoffAb-Agfrxnforfthefresistancefthatfafpersonfhasfagainstfafdse
TypesfoffInfxn
A.fSourcefoffAgent
28. ExogenousfInfxn:fcausativefagentfreachfthefbodyffromfthefoutside
29. EndogenousfInfxn:fcausativefagentfisfnormallyfpresentfinfthefbody
B.fLocation
30. LocalizedfInfxn:fremainsfconfinedftofafparticularfarea
31. GeneralizedfInfxn:finfectionfspreadsfoverfthefbodyfthroughfthefbloodforflymphaticfsystem
,C.fOthers
32. MixedfInfxn:ftwoforfmoreforganismsfcausefthefdse
33. Subclinical/inapparent:finfxnsfthatfdoesfnotfcausefdetectablefmanifestationsf(ex:fSTD)
34. Latent:finfxnfisfcontrolledfbyfdefensivefpowersfbutfactivatedf(ex:fPTB)
35. CommunicablefDisease:fdsefcapablefoffbeingftransmittedffromfonefpersonftofanother
Immunity
>fafstatefoffhavingfsufficientfbiologicalfdefensesftofavoidfinfxn,fdse,forfotherfunwantedfbiologicalfinvas
ion
>fderivedffromf“immunis”f–
f Latinfmeaningf “exemptionffromfmilitaryf service,f taxf paymentsf &f otherf publicf services”
2fGeneralfTypes:
1. Innate:fnonspecific;fpresentfatfbirth
:fresponseftofafforeignfinvaderfisfveryfsimilarffromfonefencounterftofthefnext
ffregardlessf off thef #f off timesf thef invaderf wasf encountered
• 2fStages
o Immediate:foccursfwithinf4fhours
o Delayed:fbetweenf4-96fhrsfafterfexposure
• Classes
I. WhitefBloodfCellfAxn
II. InflammatoryfResponse
III. Physicalf&fChemicalfbarriers
IV. Immunefregulation:fidentifyfAgfasf“non-self”;fprodxnfoffcytokines
2. Acquiredf(Adaptive):fspecific;fdevelopsfafterfbirth
ffffffff:fresponsef tof afforeignf invaderf thatf increasesf inf intensityf with
ffffffffffrepeatedf exposuref tof thef invadingf agent
• 2fTypes
o Natural:foccursfthrufcontactfwithfagent
o Artificial:fdevelopsfonlyfthrufdeliberatefaxns
• 2fSubtypes:finvolvefhumoralf&fcellularfimmunologicfresponses
o Active:fimmunologicfdefensesfdevelopedfbyfthefperson’sfownfbody
ffff:f lastsfforfmanyf yrsf orf evenf af lifetimef(ex:fvaccines)
o Passive:ftemporaryfimmunityftransmittedffromfafsourcefoutsidefthefbody
fffffffffthatf hasf developedf immunityf thruf previousf dsef orf immunization
(ex:fimmunefglobulins/antiserum;ftransferfoffAbffromfmotherfinfuteroforfthrufBF)
fLouisfPasteur:fGERM fTHEORYfoffDse:ftalksf aboutf howf bacteriaf causedf dse
a. NaturalfPassive:fimmunityfacquiredffromfmaternalfAb
b. NaturalfActive:fimmunityfacquiredfafterfanfinfxn
c. ArtificialfPassive:fantibodyftransferf
d. ArtificialfActive:facquiredffromfimmunization
IMMUNEfSYSTEM
➢ afcomplexf&fintricatefnetworkfoffspecializedfcells,ftissuesf&forgans
➢ cellsfoffthefimmunefsystemfseekfoutf&fdestroyfdamagedfcellsf&fforeignftissue,fyetfrecognizef
&fpreservefhostfcells
➢ FUNCTIONS:
a. Defendingf&fprotectingfthefbodyffromfinfxnfbyfbacteria,fviruses,ffungif&fparasites
b. Removingf&fdestroyingfdamagedforfdeadfcells
c. Identifyingf&fdestroyingfmalignantfcells,ftherebyfpreventingftheirffurtherfdevtfintoftu
mors
➢ Activatedfbyfminorfinjuriesfsuchfasfsmallflacerationsforfbruises,forfbyfmajorfinjuriesfsuchfasfb
urns,fsurgeriesf&fsystemicfdses
➢ Responsefoffthefimmunefsystemfmayfbefnonspecificforfspecific
,Components
1. LEUKOCYTESf(4,500-10,000fcells/mm3)
➢ WBCsfarefthefprimaryfcellsfinvolvedfinfbothfnonspecificf&fspecificfimmunefsystemfresponses
➢ Mobilefunitsfoffthefimmunefsystemfthatfdetect,fattackf&fdestroyfanythingfthatfisfrecognizedfasffo
reign
➢ Ableftofmovefthruftissuefspaces,flocatingfdamagedftissuesf&finfxnfbyfrespondingftofthefchemic
alsfreleasedfbyfotherfleukocytesforfdamagedftissuef–fCHEMOTAXIS
➢ Dividedfintof3fmajorfgroups:fgranulocytes,fmonocytesf&flumphocytes
a. Granulocytesf(60-80%)
• Havefafshortflifespan,fmeasuredfinfhrsftofdays
• Playfafkeyfrolefinfprotectingfthefbodyffromfharmfulfmicroorganismsfduringfacutefinf
lammationf&finfxn
• 3ftypes:fneutrophils,fbasophils,feosinophils
➢ Neutrophilsf(55-70%)
• alsofcalledfpolymorphonuclearfleukocytesf(PMNs/polys)
• mostfplentiful
• arefphagocyticfcellsfresponsiblefforfengulfingf&fdestroyingfforeignfagents,fparticul
arlyfbacteriaf&fsmallfparticles
• 1stfpagocyticfcellsftofarrivefatfthefsitefoffinvasion,fdrawnfbyfchemicalsfreleasedfbyfd
amagedftsef&finvadingforganismsf(chemotaxis)
• Segmentedforfsegsf(maturefform),fbandsf(immature)
➢ Eosinophilsf(1-4%)
• arefalsofphagocyticfcellsfbutfareflessfefficientfatfthisfprocessfthanfneutrophils
• foundfinflargef#sfinfthefrespif&fGIftracts
• thoughtftofprotectfbodyffromfparasiticfworms
• thesefcellsfsurroundfthefparasitef&freleaseftoxicfenzymesffromftheirfcytoplasmicfgr
anules
• alsofinvolvedfinfthefhypersensitivityfresponse
➢ Basophilsf(0.5-1%)
• arefnotfphagocytic
• granulesfcontainfproteinsf&fchemicalsfsuchfasfheparin,fhistamine,fbradykinin,fser
otonin,f&fslow-reactingfsubstancesfoffanaphylaxisf(Leukotrienes)
• thesefsubstancesfarefrelasedfintofthefbloodstreamfduringfanfacutefhypersensitivit
yfrxnforfstressfresponse
b. Monocytesf(2-3%)f&fMacrophages
• theflargestfoffthefleukocytes
• migrateftofvariousftissuesfthroughoutfthefbody,fattachingfthemselvesftoftheftissue,f
whereftheyfremainfforfmonths/yrsfuntilftheyfarefactivated
• maturefintofmacrophagesfafterfsettlingfintoftheftissuesf&farefdifferentiatedfbyfthefti
ssuefinfwhichftheyfreside:
➢ histiocytesf–floosefconnectiveftissue
➢ Kupfferfcellsf–fliver
➢ Alveolarfmacrophagesf–flungs
➢ Microgliaf–fbrain
• alsoffoundfinfthefspleen,ftonsils,flymphfnodesf&fbonefmarrow
• activelyfphagocyticfwhichfthefcapacityftofphagocytizeflargefforeignfparticlesf&fcellf
debris
• likefneutrophils,fmacrophagesfarefdrawnftofanfinflamedfareafbyfchemicalsfrelease
dffromfdamagedftissues
• importantfinfthefbody’sfdefensefagainstfchronicfinfxnsfsuchfasfTB,fviralfinfxnsf&fcer
tainfintracellularfparasiticfinfxns
c. Lymphocytesf(20-40%)
, • principalfeffectorf&fregulatorfcellsfoffspecificfimmunefresponse
• protectfthefbodyffromfmicroorganisms,fforeignftissuef&fcellfmutationsforfalteration
s
• immunefsurveillance:flymphocytesfmonitorfthefbodyfforfcancerousfcellsf&feliminat
eforfdestroyfthem
• constantlyfcirculatefthenfreturnftofconcentratefinflymphoidftissuesf(lymphfnodes,fs
pleen,fthymus,ftonsils,fPeyer’sfpatchesf&fappendix)
• 3ftypes:fTflymphocytesf(T-cells),fBflymphocytesf(B-
cells)f&fnaturalfkillerfcellsf(NKforfnullfceslls)
LYMPHOIDfSYSTEM
➢ consistsfofftheflymphfnodes,fspleen,fthymus,ftonsils,flymphoidftissuefscatteredfinfconnectivef
tissuesf&fmucosa,fandfthefbonefmarrow
➢ centralf&fperipheralflymphoidforgans
• LymphfNodes
o arefsmall,froundforfbean-
shapedfencapsulatedfbodiesfthatfvaryfinfsizef&farefdistributedfthroughoutfthefbody
o 2ffunctions
▪ Filterfforeignfproductsforfantigensffromftheflymph
▪ Housef&fsupportfproliferationfofflymphocytesf&fmacrophages
• ThymusfGland
o locatedfinfthefsuperior,fanteriorfmediastinalfcavityfbeneathfthefsternum
o reachesfmaximumfsizefatfpubertyfthenfbeginsftofatrophy
o byfadulthood,fitfisfdifficultftofdifferentiateffromfsurroundingfadiposeftissuefevenfthoug
hfitfremainsfactive
o infthefelderly,fthefvastfmajorityfoffthefthymusftissuefhasfbeenfreplacedfbyfadiposef&ffi
brousfconnectiveftissue
o duringffetalflifef&fchildhood,fthefthymusfservesfasfafsitefforfthefmaturationf&fdifferenti
ationfoffTfcells
o Thymosin,fanfimmunoregulatoryfhormonefoffthefthymus,fstimulatesflymphopoiesis
• ComplementfSystem
o Consistsfoffapproxf20fcomplexfplasmafCHONsfthatfarefactivatedfbyfaftissuefinjuryforf
Ag-Abfrxn
o Involvedfinfbothfnonspecificf&fspecificfimmunefresponses
o Resultsfinfthefproductionfoffeffectorfmoleculesfthatfarefinvolvedfinfthefprocessfoffinfla
mmation,fphagocytosisf&fcellflysisforfdestruction
f A.fNONSPECIFICfINFLAMMATORY/IMMUNEfRESPONSE
▪ barrierfprotectionfisfthefbody’sf1stflinefoffdefensefagainstfinfxn
▪ skinfasfthefprimaryfbarrier
▪ mucousfbarrierfwhichftrapfmicroorganismsf&fotherfforeignfsubstancesfprotectsfmembrane
sfliningfinnerfsurfacesfoffthefbodyf
▪ ciliaryfmovt
▪ washingfaxnfofftearsforfurine
▪ bactericidalfsubstancesffoundfinfbodyffluidsfsuchfasfgastricffluid,fzincfinfprostaticffluidf&flys
ozymefinftears,fnasalfsecresions,fsalivaf&fsweat
▪ whenf1stflinefoffdefensesfarefbreached,fresultingftissuefdamageforfforeignfmaterialfenterin
gfthefbodyfinducesfafnonspecificfimmunefresponsefisfknownfasfinflammation
▪ Inflammation:fanfadaptivefresponseftofinjuryfthatfbringsffluid,fdissolvedfsubstancesf&fblo
odfcellsfintofthefinterstitialftissuesfwherefthefinvasionforfdamagefhasfoccurredfthereby,fthefi
nvaderfisfneutralizedf&feliminated,fdestroyedftissuefremovedf&fthefprocessfoffhealingfandfr
epairfinitiated
▪ 3fstages:fVascularfResponse,fCellularfResponsef&fTissuefRepair
1. VascularfResponse
