exercise 38 the lymphatic system and immune response
TRANSCRIPT
Exercise 38
The Lymphatic System and Immune Response
Lymphatic System
Lymphatic vessels Lymphatic tissues
Tonsils Primary lymphatic organs
Thymus and Bone marrow Secondary lymphatic organs
Lymph nodes, spleen
Lymphatic System
Lymphatic System
LymphFluid lost from the capillariesEdema
Functions of the lymphatic system:Transport lymph to the blood vesselsProtects the body
Lymphatic vessels
Lymphatic capillaries Lymphatic collecting vessels Lymphatic trunk Right lymphatic duct - drains lymph
from:Head right upper extremityRight thoraxDrains into right subclavian vein
Lymphatic vessels
Thoracic duct – drains lymph from:Rest of the bodyDrains into left subclavian vein
Cisterna chyli Characteristic of the lymphatic vessels
Walls with 3 tunicsPresence of valvesPresence of abundant anastomoses
Lymphatic vessels
Primary lymphoid organs
Bone marrowContain the stem cell that will give
rise to all lymphocytesSite of B cell differentiation or
immunocompetency Thymus
Site of T cell differentiation or immunocompetency
Thymus
Secondary lymphatic organs
Lymph nodesBean-shaped NumerousRegional lymph nodes:
• Cervical• Axillary• Inguinal, etc
HilusAfferent and efferent vessels
Secondary lymphatic organs
MicroscopyCapsule and subcapsular sinusTrabeculaCortex
• Outer cortex (follicles)• Germinal center containing
dividing B cells• Deep cortex or paracortical area
• Contain T cells
Secondary lymphatic organs
Medulla• Medullary cords• Medullary sinuses• Contain macrophages and plasma
cells
Secondary lymphatic organs
SpleenCapsuleWhite pulp
• Central artery• Lymphocytes
Red pulp• Venous sinuses• Reticular tissue• Macrophages arranged I splenic
cords
Spleen
Lymphoid tissues
TonsilsOne pharingeal Two palatinesTwo lingualsPresence of germinal centerPresence of crypts
Tonsils
The immune response It is a systemic response Destroys or neutralizes foreign substances Characteristics of immune responses
Memory• Immunocompetent lymphocytes are
monospecificSpecificityAbility to differentiate self from nonself
The immune response
AntigensForeign proteinsPolysaccharidesHaptens
Lymphocytes Responsible for the immune
response Autoimmunity
Organ, cells and cell interaction of the immune response
Hemocytoblasts in the bone marrow give rise to lymphocytes
Types of Lymphocytes:B - will stay in the bone marrow for
maturation (immunocompetence)T - will migrate to thymus for
maturation (immunocompetence)Natural Killers
Organ, cells and cell interaction of the immune response
B and T cell will then leave bone marrow and thymus, enter the blood stream and travel to secondary lymphatic organs Site for clonal selection
Organ, cells and cell interaction of the immune response
B and T cell will bind to specific antigens and then undergo clonal multiplication
B cell may becomeMemoryPlasma cellHumoral immunity
Organ, cells and cell interaction of the immune response
T cell may becomeMemoryCytotoxicHelperSuppressorCellular immunity
Antibodies and tests for their presence
Characteristics of antibodies or Immunoglobulins (Igs)Produced only by plasma cellsThey are plasma proteins
(gamaglobulins)Found in all body secretions
Antibodies and tests for their presence
Classes of antibodiesIgM, IgG, IgA, IgD, IgE
Structure of the immunoglobulins2 heavy chains2 light chains
Antibody