Embed Size (px)
Citation preview
Cells and Tissues of the Cells and Tissues of the Immune SystemImmune System
AgendaAgenda
Cells of the Immune SystemCells of the Immune System Tissues/Organs of the Immune Tissues/Organs of the Immune
SystemSystem
Menu FB
LymphocytesLymphocytes
Menu FB
LymphocytesLymphocytes
B CellsB Cells T CellsT Cells NK CellsNK Cells
Menu FB
B Cell T HelperCD4+
T CytotoxicCD8+
Lymphocyte Subsets
Naive Activated EffectorPhases of
LymphocyteActivation
Menu FB
Accessory CellsAccessory Cells
Mononuclear PhagocytesMononuclear Phagocytes– Monocytes and MacrophagesMonocytes and Macrophages
Dendritic CellsDendritic Cells
Monocytes and Monocytes and MacrophagesMacrophages
Menu FB
Menu FB
Dendritic CellsDendritic Cells Transport Antigens to L. nodesTransport Antigens to L. nodes InitiationInitiation of T Cell Responses of T Cell Responses
Menu FB
Neutrophil
Eosinophil
Basophil
Thymus
Bone MarrowBursa
Peyer's Patches(Ruminants,Pigs)
Primary/Generative
Spleen
Lymph Nodes
Cutaneous
Mucosal
Secondary
Lymphoid Organs
Lymphoid OrgansLymphoid OrgansThe organs in which lymphocytes develop are called The organs in which lymphocytes develop are called
primary lymphoid organs (PLO)primary lymphoid organs (PLO)..
The organs in which mature lymphocytes reside and The organs in which mature lymphocytes reside and encounter Ag are calledencounter Ag are called secondary lymphoid organs secondary lymphoid organs
(SLO). (SLO).
D
Difference between PLO and SLO
CharactersCharacters PLOPLO SLOSLO
OriginOrigin Ectoendodermal Ectoendodermal junction or endodermjunction or endoderm MesodermMesoderm
Time of developmentTime of development Early in embryonic lifeEarly in embryonic life Late in fetal lifeLate in fetal life
PersistencePersistence Involute after pubertyInvolute after puberty Persists in adultPersists in adult
Effect of removalEffect of removalLoss of lymphocytesLoss of lymphocytesLoss of immune Loss of immune responseresponse
Nil or no effectNil or no effect
Response to antigenResponse to antigen UnresponsiveUnresponsive Fully reactiveFully reactive
ExamplesExamplesThymus, bursa of Thymus, bursa of Fabricius, Peyer’s Fabricius, Peyer’s patches etcpatches etc
Spleen, lymph nodes Spleen, lymph nodes etc.etc.
ThymusThymusEffect of removal/ Function•No. of circulating lymphocytes decreases•Presence of lymphocytes in T dependant area decreases•Failure in graft rejection
•Size is greatest in new born•Absolute size is greatest at puberty•Atrophies after puberty
Having two parts-1.Cortex- produce rapidly dividing thymocytes.
2.Medulla- within medulla, few round bodies are seen, called thymic / Hassall’s corpuscles.
Menu FB
(T Cell Progenitors)
Menu FBSite of T Cell Maturation
Bone MarrowBone Marrow
Site of hematopoiesis.Site of hematopoiesis. Site of B cell maturation in mammals.Site of B cell maturation in mammals.
Bursa of FabriciusBursa of Fabricius• Site of B cell maturation in birds.• Found in birds but not in mammals.Having two parts-1. Cortex- contains lymphocytes, plasma cells and
macrophages2. Medulla- contains lymphocytes
Effect of removal/ Function•Presence of lymphocytes in T independent area decreases•Plasma cells in lymphoid tissues decreases•Serum immunoglobulins decreases •Antibody formation decreases
Peyer’s Peyer’s PatchesPatches
Site of B Cell Site of B Cell Maturation Maturation Found in Found in Pigs and Pigs and Ruminants Ruminants
Two types of PP-•Jejunal•Ileo-cecal
Menu FB
Secondary Lymphoid OrgansSecondary Lymphoid Organs
Lymph NodesLymph Nodes Local sites of specific immune response.Local sites of specific immune response. Strategically placed on lymphatic channels.Strategically placed on lymphatic channels.
Menu FB
Menu FB
SpleenSpleen Site of immunological responses against blood-Site of immunological responses against blood-
borne Ags.borne Ags. White pulpWhite pulp rich in lymphoid cells. rich in lymphoid cells. Red pulpRed pulp rich in myeloide cells. rich in myeloide cells.
Menu FB
Menu FB
Menu FB
Menu FB
Menu FB
Evolutionary distribution of lymphoid tissues
