Tissues of the Immune System Flashcards
What are the primary/central lymphoid organs?
Bone marrow, thymus
This is where lymphocytes acquire immunocompetency
What are the secondary/peripheral lymphoid organs?
Lymph nodes, spleen, MALT (mucosa-associated lymphoid tissue)
This is where lymphocytes undergo activation
What do lymphatics contain?
Lymph - interstitial fluid, lymphocytes, antigens
What are some cellular components of the lymphatic system?
T and B lymphocytes, macrophages, plasma cells, dendritic cells
What cells form the tissue framework of the lymphatic system?
Reticular cells form the reticular tissue framework
What are the functions of the lymph node?
- Filtration of lymph
- Antigen presentation
- Lymphocyte stimulation and proliferation
- Plasma cell formation and antibody production
What makes up the cortex of the lymph nodes?
Lymphoid follicles, mantle zone, germinal center
What are the parts of a lymph node?
- Cortex
- Paracortex
- Medulla
What makes up the medulla of the lymph nodes?
Sinuses, cords
How do lymphocytes enter the lymph nodes?
Via lymphatics and leaky high endothelial venules
How do lymphocytes reenter circulation from the lymph nodes?
Via medullary sinuses
What type of cells can be found in the cortex of lymph nodes?
B cells
Lymphoid nodules
What kind of cells can be found in the paracortex of lymph nodes?
T cells
Diffuse lymphoid tissue
What type of cells can be found in the medulla of lymph nodes?
Both B and T cells
Cords, sinuses
Describe the circulation of lymph through the lymph node
- Lymph in afferent lymphatics enter through the capsule
- Subcapsular sinus
- Trabecular sinuses
- Cortex
- Paracortex
- Medullary sinuses
- Efferent lymphatic at hilum
- Single efferent lymphatic leaves through hilum
Discontinuous endothelium lines passage