IMMUNOLOGY ADAPTIVE AND INNATE IMMUNITY ADAPTIVE IMMUNITY - highly specifc or a certain pathogen - response improves with each successive encounters - remembers remembers and prevents p revents an inectious agent that had already been encountered - 2 key eatures are specifcity and memory. INNATE IMMUNITY - Non-specifc - Same response ater repeated exposure - Has no memory ELL! O" T#E IMMUNE !Y!TEM - All cells o the immune system arise rom pluripotent stem cells through two main line o dierentiation! "# the $ymp%oid $inea&e $produces lymphocytes#% 2# the mye$oid $inea&e $produces phagocytes and other cells# P#AGOYTI ELL!' P#AGOYTE!' ANTIGEN-P(E!ENTING &' ELL! )AP* - mono monocy cyte tes( s( mac macrropha ophage ges( s( )*N )*Ns s - engul enguls s pathog pathogens ens(( inter internal nali+e i+es s them them and dest destrroys them them within the cell - us uses es nonnon-spe speci cifc fc rec recogn ognit itio ion n syst system ems s - medi mediat ate e inna innate te immu immuni nity ty - consid consider ered ed the frst frst cellul cellular ar line line o dee deense nse
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A' MONONULEA( ELL!' MONOYTE! - ,eri ,erive ved d rom rom the the bon bone e mar marrow ste stem m cell cells s - unctio unction n is to engu engul l parti particle cles( s( in inter ternal nali+ i+e e them them and and destroy them - .ective in presentin& anti&ens to T $ymp%ocytes - /ong /ong-l -liv ived ed pha phago gocy cyti tic c cell cells s 0' PMN!) POLYMO(P#ONULEA( !EGMENTE(!*' NEUT(OP#IL - 1onsti 1onstitut tutes es the maori maority ty o blood blood leuk leukocy ocytes tes - !%ort-$i+ed p%a&ocytic ce$$s $ater internali+ing and destroying pathogens( they die# LYMP#OYTE! - 1entral 1entral cells cells in adaptiv adaptive e immuni immunity ty'' )roduce )roduced d at a rate rate o "345 per day'
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6he adult constitutes about "34"2 lymphoid cells( and the lymphoid tissue as a whole is about 27 o the total body weight' 1an recogni+e individual pathogens whether inside or outside o host cells Specifc immune recognition ,erived rom the bone marrow stem cells( although the 6 lymphocytes develop urther in the thymus $ the bone marrow and thymus are considered the primary lymphoid organs.#
D MA(,E(' LU!TE( O" DI""E(ENTIATION - 8eers to groups o monoclonal antibodies( each cluster binding specifcally to a particular cell marker - ,epends on computer analysis o monoclonal antibodies produced mainly in mice against human leukocyte antigens' - .xample is D also known as the common leukocyte antigen A' / ELL! )/ 0 /U(!A1 23rsa o4 4a2rici3s in c%ic5ens* - D MA(,E(6 D78 9 main marker to identiy 0 cells' D:; 9 main marker to identiy 0 cells' D:7 9 also known as 182( which is the complement receptor or 19d' 1ommonly ound in 0 cells' Associated with homing o cells' D:: 9 main marker to identiy 0 cells' D< 9 also known as 18"( which is the complement receptor or 19b' 1ommonly ound in 0 cells' Associated with homing o cells' D<: 9 c receptors or exogenous &g:( which play a role in negative signalling to 0 cells' D=: 9 ligand o 1,; in 6 cells' - 8epresents ;-";7 o circulating lymphoid pool( and are classically defned by the presence o surace immunoglobulins( seen with
pattern $when cold# or cap-like $when warm# pattern' - 6he main immunoglobulin seen on their surace are &g* and &g, - Specifcally recogni+es a particular antigen using a receptor molecule on its surace - ,evelops in the 4eta$ $i+er or ad3$t 2one marro>.
0 cells are occasionally seen with a de+e$opin& ro3&% endop$asmic retic3$3m' - 1ombats e?trace$$3$ar pat%o&ens by release o anti2odies( that bind to a particular target molecule called anti&en - ,ivide and dierentiate into p$asma ce$$s ( which produce large amounts o receptor molecule in soluble orm which are also otherwise known as antibodies ♦ ANTI/ODIE! 9 large glycoproteins ound in blood and tissue %ere t%ey de+e$op* - D MA(,E(6 D7 ? maturation marker or 6 cells 1 on$y 4o3nd in ce$$s de+e$opin& in t%e t%ym3s( and is not present in circulating 6 cells D: ? ability o 6 cells to bind to sheep erythrocytes also known as rosette 4ormation' D< 9 e?c$3si+e 4or T ce$$s ( and is involved in cell triggering' D 9 marker or T %e$per ce$$s D 9 ligand o 1,@2 in 0 cells' D@ 9 marker 4or T cytoto?ic ce$$s or T s3ppressor ce$$s D: 9 activation marker or 6 cells( also known as the 6 cell growth actor receptor or IL: receptor. - &nvolved in the control o 0 lymphocyte development and production - 6 helper and 6 cytotoxic cells are smaller( nongranular and with high N!1 ratio' 6hey also carry a structure called a =Ga$$ /ody>( which consists o a c$3ster o4 primary $ysoymes( seen in cytochemistry' - &nteracts with phagocytic cells and helps them destroy pathogens - 8ecogni+es inected cells by viruses and destroys them - ses the T() T ELL (EEPTO(* to recogni+e antigens' -
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Has the ability to release cytokines 1A6.:B8&.S B 6 1.//S! "' T #ELPE( ELL )DB ELL!* - )ositively init%o3t prior sensitiation. - ses a non-specifc recognition system - ,oes not express antigen receptors - Has the ability( ANTI/ODY-DEPENDENT ELLULA( YTOTOCIITY )AD*.
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&t is neit%er a T $ymp%ocyte nor / $ymp%ocyte.
LYMP#OYTE ATIVATION - 0oth 6 and 0 cells utili+e a :6)-dependent component $or :-protein# to induce signalling reactions' 6hese :-proteins stimulate phosphatidylinositol metabolism( at the same time a number o surace receptors or cytokines such as &/2 are produced'
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OT#E( IMPO(TANT ELL! O" T#E IMMUNE !Y!TEM A' EO!INOP#IL! )EO!IN 0 (ED 0 AIDOP#ILI* - Has the ability to engage and damage extracellular parasites 0' AUCILLA(Y ELL! - &nvolved in the development o immune response by the production and release o mediators a# Mast e$$s 9 cells that lie close to the blood vessels in all tissues' &t unctions in hypersensitivity reactions b# /asop%i$s 9 cells in the blood circulation that unction similarly to the mast cells c# P$ate$ets 9 attracts leukocytes to site o inury
!OLU/LE MEDIATO(! O" IMMUNITY I. AUTE P#A!E P(OTEIN! - )roteins produced by the $i+er that are increased rapidly during inection A' (P' -(EATIVE P(OTEIN - Name comes rom the ability to bind with the 1 protein o pneumococci OMPLEMENT &&' - D MA(,E(6 D:7 9 also known as 182( which is the complement receptor or 19d' 1ommonly ound in 0 cells' D< 9 also known as 18"( which is the complement receptor or 19b' 1ommonly ound in 0 cells - :roup o 23 serum proteins that control in
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E' ,amages plasma membranes o cells( gram $-# bacteria( and enveloped viruses 2 *AFB8 )A6HGACS B 1B*)/.*.N6 A16&A6&BN! "' LA!!IAL PAT#AY 9 initiated by antigen-antibody reaction 2' ALTE(NATIVE PAT#AY 9 initiated by certain microorganisms
YTO,INE! - *olecules involved in the signalling between cells A' INTE("E(ON! )I"N* - 1onsidered the frst $ine o4 resistance to many +ir3ses' - ,etermines how eective tissue cells interact with lymphocytes - &nduces a state o4 anti-+ira$ resistance in 3nin4ected ce$$s - &mportant in limiting certain viral inactions ♦ 9 1A6.:B8&.S B &N6.8.8BNS! 7. I"N ALP#A :. I"N /ETA <. I"N GAMMA I0oth &N A/)HA and 0.6A are produced by virally inected cells /. INTE(LEU,IN! )IL* - )roduced mainly by T $ymp%ocytes( some by mononuclear cells - *ost are involved in directing cells to divide and dierentiate . OLONY !TIMULATING "ATO(! )!"s* - ,irect division and dierentiation o bone marrow stem cells - 6he balance o the dierent 1Ss partly determines the proportion o dierent cell types which will be produced D. TUMO( NE(O!I! "ATO( )TN" ALP#A and TN" /ETA* and T(AN!"O(MING G(OT# "ATO( )TG" /ETA* - &mportant in mediating in
"' "a2 9 part o the antibody where the antigen can be bound 2' "c 9 part that interacts with the cells o the immune system
N./. )hagocytes can recogni+e antigens using either an activated $19b# or antibody that act as opsonins( but phagocytosis is more eective i both are present' Anti&en 9 any molecule which can be specifcally recogni+ed by adaptive elements ♦ )A86S B AN AN6&:.N! "' EPITOPE 9 )art o the antigen where the antibody binds to' LONAL !ELETION - .ach lymphocyte is capable o recogni+ing only one particular antigen - A specifc antigen selects or the specifc clones o its own antigenbinding cells IMMUNE E""ETO( ME#ANI!M! A. Anti2ody /indin& - Antibodies bind to the outer membrane o some rhinoviruses $those that cause common colds# can prevent viral paricles rom binding to host cells /. Acti+ation o4 omp$ement 2y Anti2ody - Antibodies in circulation can activate the classical complement pathway in order to cause lysis to oreign antigens . Anti2odies act as Opsonins - Bpsonins are antibodiesJ complement that can coat a pathogen and make phagocytosis more eective D. P%a&ocytosis - )hagocytic cells proceed to engul antigen-carrying microbe by extending their pseudopodia around it' the microbe is then internali+ed in a phagosome and reactive oxygen intermediates $8B&s# produced by monocytes are toxic to bacteria( or neutrophils can secrete transerrin which chelates iron and prevents bacteria rom acKuiring this vital nutrient( or fnally granules rom lysosomes can use with the phagosome( pouring digestive en+ymes into the phagolysosome( digesting its contents' E. ytoto?ic (eactions
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,irected against >%o$e ce$$s which are too large or phagocytosis - Attacking cells direct their granules towards the target cell( in contrast to phagocytosis where it is directed against the phagosome' - 6 cells contain molecules called perorins which can punch holes in the outer membrane o the target - Some cytotoxic cells can signal to the target to seldestruct by ragmentation o ,NA or otherwise known as Apoptosis.
IN"LAMMATION - *aniestation o inection( wherein the body concentrates immune products toward the site o inection' MAFO( EVENT! T#AT OU( DU(ING IN"LAMMATION 7. &ncreased blood supply to site o inection :. &ncreased capillary permeability due to the retraction o endothelial cells' 6his permits larger molecules to escape rom capillaries and allows soluble mediators to reach the site o inection <. /eukocytes migrate out o the capillaries into surrounding tissues $diapedesis*' DE"EN!E! AGAIN!T ECT(AELLULA( AND INT(AELLULA( PAT#OGEN! - &n dealing with extracellular pathogens( the immune system aims to destroy the pathogen itsel( or neutrali+e its products' - &n intracellular pathogens( there are two options' .ither the 6 cells can destroy the inected cell $cytotoxicity# or they can activate the cell to deal with the pathogen itsel' VAINATION - )8&N1&)/.! based on the two key elements o adaptive immunity( namely specifcity and memory' - 6he aim in vaccine development is to alter a pathogen or its toxins in such a way that they become innocuous without losing their antigenicity' IMMUNOPAT#OLOGY - 6he immune system itsel is the cause o disease or other undesirable conseKuences' 9 GACS B &**NB)A6HB/B:C "' Mista5en reco&nition o4 se$4 anti&ens' AUTOIMMUNITY - 6he body reacts to not only oreign pathogens but also to host cells
2' An ineHecti+e imm3ne response' IMMUNODE"IIENY - ,eective immune elements( unable to fght inection 9' An o+eracti+e imm3ne response' #YPE(!EN!ITIVITY - 6he immune response causes more damage than the pathogen itsel'
