This document describes the major lymphoid organs and cells of the immune system. It discusses the thymus, spleen, bone marrow, and lymph nodes as the major lymphoid organs where lymphocytes develop and mature. It also describes the minor lymphoid organs. The document outlines the development of B and T cells and their circulation through lymphoid tissues. It provides details on the structure and function of lymph nodes and discusses the roles of macrophages, mast cells, basophils, eosinophils, neutrophils, and natural killer cells in the immune response.

1. Figure'1)7'

2. Major&Lymphoid&Organs&
• Thymus&
– Located(in(the(front(of(the(upper(chest(
– Nursery(for(the(development(of(T(cells.(
• Spleen(
– Located(in(the(upper(le=(side(of(your(abdomen(
– Filters(out(foreign(organisms(from(blood(
– Removing(old(or(damaged(platelets(and(red(blood(cells(
– Stores(extra(blood(and(releases(it(as(needed(
– Developmenof(white(blood(cells(
– Removal(may(lower(resistance(to(infecDon.(
• Bone&marrow(
– Located(in(the(middle(of(bones,(specifically(vertebrae,(pelvic,(and(leg(
bones(
– Generates(T(cells,(B(cells,(and(macrophages(
No es parte d los major lymphoid organs

3. • Lymph&nodes&
– Hundreds'of'lymph'nodes'are'located'throughout'your'body'
– Filter'lymph'fluid'
– Remove'anDgens,'bacteria,'and'cancer'cells'
– Weblike'structure'traps'foreing'agents'allowing'macrophages,'
anDbodies,'and'T'cells'to'destroy'them.''
– Removal'any'lymph'nodes'during'breast'cancer'surgery'does'not'
compromise'your'overall'lymph'node'protecDon.''
Minor&Lymphoid&Organs&

4. Figure'1)11'

6. Copyright(©(The(McGrawIHill(Companies,(Inc.((
B&and&T&cell&
Developpment&

7. CirculaDng(lymphocytes(encounter(anDgen(in(peripheral(
lymphoid(organs.(
• Naive(lymphocytes(recirculate(constantly(through(
peripheral(lymphoid(Dssue,(here(illustrated(as(a(
popliteal(lymph(node—a(lymph(node(situated(
behind(the(knee.((
– In(the(case(of(an(infecDon(in(the(foot,(this(will(be(the(
draining(lymph(node,(where(lymphocytes(may(
encounter(their(specific(anDgens(and(become(
acDvated.(
• Both(acDvated(and(nonacDvated(lymphocytes(are(
returned(to(the(bloodstream(via(the(lymphaDc(
system.(

9. OrganizaDon'of'a'lymph'node.'
• As'shown'in'the'diagram'on'the'le=,'which'shows'a'
lymph'node'in'longitudinal'secDon,'a'lymph'node'
consists'of'an'outermost'cortex'and'an'inner'medulla.'
The'cortex'is'composed'of'an'outer'cortex'of'B'cells'
organized'into'lymphoid'follicles,'and'deep,'or'
paracorDcal,'areas'made'up'mainly'of'T'cells'and'
dendriDc'cells.''
• When'an'immune'response'is'under'way,'some'of'the'
follicles'contain'central'areas'of'intense'B)cell'
proliferaDon'called'germinal'centers'and'are'known'as'
secondary'lymphoid'follicles.'These'reacDons'are'very'
dramaDc,'but'eventually'die'out'as'senescent'germinal'
centers.''

11. • Lymph'draining'from'the'extracellular'spaces'of'the'body'
carries'anDgens'in'phagocyDc'dendriDc'cells'and'phagocyDc'
macrophages'from'the'Dssues'to'the'lymph'node'via'the'
afferent'lymphaDcs.'These'migrate'directly'from'the'sinuses'
into'the'cellular'parts'of'the'node.'Lymph'leaves'by'the'efferent'
lymphaDcs'in'the'medulla.'The'medulla'consists'of'strings'of'
macrophages'and'anDbody)secreDng'plasma'cells'known'as'the'
medullary'cords.''
• Naive'lymphocytes'enter'the'node'from'the'bloodstream'
through'specialized'postcapillary'venules'(not'shown)'and'leave'
with'the'lymph'through'the'efferent'lymphaDc.'The'light'
micrograph'shows'a'transverse'secDon'through'a'lymph'node,'
with'prominent'follicles'containing'germinal'centers.'

14. Mucosal Associated Lymphoid Tissues (MALT)

15. 86'RTA'

16. 87(RTA(

17. 88'RTA'

18. Macrophage(phagocytosing(Streptococcus*pyogenes((

19. 90'RTA'

20. 91(

21. MONOCYTE7MACROPHAGES&
Types&
– &&&&&&&&Macrophages&7&in&connecGve&Gssues&
– &&&&&&&&Alveolar&macrophages&7&in&lung&
– &&&&&&&&Kupffer&cells&7&liver&
– &&&&&&&&Langerhans&cells&7&epidermis&
– &&&&&&&&DendriGc&–travel&from&Gssues&to&lymph&nodes&
– &&&&&&&&Microglia&7&brain& 92'RTA'

22. Macrophages(are(phagocytes(
• Recognize(pathogens(via(surface(receptors(
– Mannose(and(scavenger(receptors(
– TollIlike(Receptors((TLRI2,(TLRI4)(
– CD14(
• Destroy(pathogens(in(phagosomes(
– May(be(able(to(stop(invasion(at(this(stage(
• Secrete(numerous(cytokines(
93(RTA(

23. Macrophage&cytokine&funcGons&
• AcDvate'natural'killer'cells'
• Induce'the'inflammatory'vascular'response'
• Induce'the'inflammatory'cellular'response'
Empece a grabar 1:34

24. Chemotaxis
Mast
Cell
Mast
Cell
PMN
Eosinophil
95(RTA(

25. Chemotaxis'

26. Release&of&macrophage&chemotacGc&
factor&

27. Figure'1)12'
Extrabasacion‣

28. PMN&ROLLING,&STOPPING,&AGGREGATING,&
AND&MIGRATING&
ROLLING STOPPING
AGGREGATION &
SHAPE CHANGE
TRANSENDOTHELIAL
MIGRATION
L-SELECTIN
P-SELECTIN
E-SELECTIN
INTEGRINS
ICAMS
VCAMS
CD11/CD18
P-SELECTIN
INTEGRINS
ICAM
VCAM
PCAM
99(RTA(

29. SEROUS&AND&&
FIBRINOUS&&EXUDATES&

30. Interferones&(IFN)&
• Propiedades(anDvirales(
– Modulan(la(acDvidad(de(las(células(NK(y(
macrófagos(
• Interferones(α,(β(y(γ(
– se(encuentran(en(muchas(especies(
– producidas(por(muchas(células(
• fibroblastos,(leucocitos(
• célula(infectada(con(un(virus(
101(RTA(

31. Interferones&(IFN)&
Protege'células'no'infectadas'por'virus'
• produce'derrepresión'de'dos'genes'
– proteína'quinasa'bloquea'la'transcripción'de'mRNA'
• gene'que'cataliza'la'formación'de'un'polímero'pequeño'
– acDva'una'endonucleasa''
– degrada'el'mRNA'viral'y'del'huésped''
• Produce'un'círculo'de'células'sanas'
102'RTA'

32. MAST(CELLS(
103(RTA(

33. MAST CELL
Chemicals
Mechanical
Injury
IgE + Allergen
Activated
Complement
Mast Cell Degranulation
104'RTA'
Dentro de los granos hay acido araquidonico.•

34. Arachidonic&acid&metabolites&
a. Prostaglandins&
&&&L&vasodilaGon,&vascular&permeability,&pain&
b. Thomboxane&A2&(from&platelets)&
&&L&&vasoconstricGon,&bronchoconstricGon,&and&platelet&
aggregaGon&
c. Leukotrienes&(from&mast&cells&and&WBC)&
&L&LTC4,D4,E4&=&SRSA&(Slow&reacGng&substance&of&
anaphylaxis)&
&L&LTB4&=&ECFA&(chemotacGc&for&eosinophils&and&
neutrophils)&
d. Platelet&acGvaGng&factor&
105(RTA(
Parte d las histaminas, leucotrienos,etc......van a nurstros tejidos y x eso gotea la nariz, etc•
Benadryl- bloquea los receptores d la histamina (1rst genration)•
De 2nd generacion (allegra, etc) bloquea la histamina•

35. 106'RTA'

36. ARACHIDONATE&METABOLISM&
ARACHIDONATE
PROSTAGLANDIN
PRECURSOR
PROSTAGLANDINS
EX. PGI2 AND PGE THROMBOXANES
LEUKOTRIENE
PRECURSOR
LTB4
LTC4
LTD4
LTE4
OXYGEN
RADICALS
PLATELET
ACTIVATING
FACTOR
COX 1 &2 LIPOXYGENASE
107(RTA(
Todas son bn inflamatorias (los ultimos de cada columna)‣
Leucotrienos bn importantes en el asma•
Cingulair bloquea leucotrienos◦

37. BASOPHILS&
a. PhagocyGc&
b. Release&histamine,&leukotrienes,&
prostaglandins&
108'RTA'

38. EOSINOPHILS&
a. Release&numerous&inflammatory&cytokines&that&can&
result&in&prolonged&or&recurrent&inflammaGon&and&
Gssue&damage&
b. Produce&basic&caGonic&protein&which&kills&parasites,&
also&produces&chemotacGc&factors&to&parasites&
c. Are&a&key&part&of&anaphylaxis&and&allergy&response&
109(RTA(

39. INFLAMMATORY&CELLS&IN&TISSUES&
110'RTA'
*****empece otra vez amgrabar 1:50

40. POLYMORPHONUCLEAR&
NEUTROPHIL&
111(RTA(
Pare a las 1:55 y emepce 1:57

41. PMNs&aracted&to&wound&area&by&chemotacGc&
factors&of&the&immune&response&or&by&products&of&
bacterial&infecGon.&
112'RTA'
Animacion leucotrinos extravasation (kuby inmunology)•
pare 1:59
Comenzo 2:08

42. Phagocytosis
C3b
Antibody
Encapsulated
Bacteria
Lysozyme and
elastase
Cationic
Proteins
Lactoferrin
Lactic Acid and
Toxic Oxygen
Radicals
113(RTA(
Fagositosis ayudada x la opsonizacion‣

43. Quimiotáxis'y'Fagocitósis'
Video (garland science)‣

44. Neutrophil&phagocytosis&&
occurs&by&extension&of&&
pseudopods&toward&
&bacteria&and&debris&&
with&engulfment&and&&
digesGon&through&release&&
of&hydrolyGc&enzymes&&
and&oxygen&radicals.&
115(RTA(

45. OpsonizaDon'
Video‣

46. Phagocytosis&is&facilitated&by&
opsonizaGon&
CoaGng&of&the&bacteria&with&anGbody&and&
complement&C3b.&&
Neutrophils&bind&with&C3b&and&anGbody&at&Fc&
receptor.&&
FibronecGn&and&CLreacGve&protein&can&opsonize&
bacteria&
117(RTA(

47. 118'RTA'

48. Fagocitosis&y&Muerte&Intracelular(
119(RTA(

49. Mecanismo&de&Muerte&Dependientes&de&O2&
• Formación'de'Intermediarios'ReacDvos'de'Oxígeno'(ROI)'
– a'parDr'del'NADPH'
– Vía'del'Monofosfato'de'Hexosa'(presencia'de'una'oxidasa)'
• NADPH'+'O2''NADP+'+'•'O2
)''
' ' 'Aniones'de'superóxido'(•O2
))''
' ' ' '' ' ''''''dismutasa'de'H2O2'
' ' 'estables'H2O2'
' ' ' '' ' 'Fe2+''
' ' 'Radicales'hidroxilo'(•OH)' ''
' ' ' ' ' '''''mieloperoxidasa'(MPO)'
' ' ' ' ' '''''halógenos'
' ' 'estables'haloaminas'(cloramina)'
120'RTA'

50. Mecanismos&de&muerte&intracelular&
dependientes&de&oxígeno(
121(RTA(

51. Mecanismos&de&muerte&dependientes&de&O2.'
• Intermediarios'ReacDvos'de'Nitrógeno'(RNI)''
– a'parDr'de'O2'y'L)arginina'
– sintasa'del'óxido'nítrico'(iNOS)'
• enzima'inducible'
• Radicales'de'peroxinitritos'(•NOOO)'
– (•NO)+'(•O2
))''
– para'eliminar'organismos'que'escapan'del'fagosoma'
• invaden'el'citosol'
122'RTA'

52. Mecanismos&Independientes&de&O2(
– Catepsinas(
– Defensinas(de(bajo(peso(molecular(
– Proteínas(caDónicas(de(alto(peso(molecular(
– Permeability(Increasing(Protein((BPI)(
– Lisozima(
– Lactoferrina(
– Enzimas(proteolíDcas(
123(RTA(

53. Mecanismos&Independientes&de&
Oxígeno'
124'RTA'

54. Células&Citotóxicas(
Células(NK((natural'killer)'
 Linfocitos(grandes((granulares)(
 Reconocen(células(infectadas(con(virus((receptores)(
 Inducen(apoptosis((PCD)(
 FasL(se(une(al(receptor(Fas(en(la(célula(blanco(
 Degranulación((
 Perforinas(
 TNFβ(
 Granzimas(
 ATP(ionizado(
 inducen(apoptosis(
125(RTA(
matan celulas w estan infectadas, le salen senales en la superficies.•
Ellas matan a la celula pero las d alrededor no se afectan, el atp ionizadp hace q halla‣
apoptosis.

55. 126'RTA'

56. Todo lonq liberan los macrofagos. Sirven d semales•

57. 128'RTA'

58. 129(RTA(
****Aprenderse las marcadas****

59. 130'RTA'

60. 131(RTA(

61. Stos mismo sreceptores los encontramos en los macrofagos‣

62. InfecDon(triggers(an(inflammatory(response.(
• Macrophages(encountering(bacteria(or(other(types(of(
microorganisms(in(Dssues(are(triggered(to(release(cytokines(that(
increase(the(permeability(of(blood(vessels,(allowing(fluid(and(
proteins(to(pass(into(the(Dssues.(They(also(produce(chemokines,(
which(direct(the(migraDon(of(neutrophils(to(the(site(of(infecDon.((
• The(sDckiness(of(the(endothelial(cells(of(the(blood(vessel(wall(is(
also(changed,(so(that(cells(adhere(to(the(wall(and(are(able(to(crawl(
through(it;(first(neutrophils(and(then(monocytes(are(shown(
entering(the(Dssue(from(a(blood(vessel.((
• The(accumulaDon(of(fluid(and(cells(at(the(site(of(infecDon(causes(
the(redness,(swelling,(heat,(and(pain(known(collecDvely(as(
inflammaDon.(Neutrophils(and(macrophages(are(the(principal(
inflammatory(cells.((
PAMPs- pathogen associated molecular patterns‣

63. Innate'RecogniDon'of'Microbes'
Video