L 4 - Anatomy Of IS Flashcards
(27 cards)
Tissues and organs of IS
Name primary lymphoid organs and their function
Draw haematopoesis differentiation of cells
Function of secondary lymphoid organs
structure of lymph node and immune functions
- fluid carrying antigens/ pathogens enter lymph node through afferent lymphatic vessels and filtered through sinuses
- antigen presentation- DC and other APC in cortex and paracortex capture and process antigens presenting them to naive T cells ➡️ activation and proliferation of T cells. When activated T cells migrate to medulla where they can interact with B cells
- activated B cells in medulla differentiate into PC which produce Ab specific to recognised antigen. Enter blood stream
-lymphatic recirculation- T and B cells can enter lymph node via blood vessels and afferent and efferent lymphatic lymphatic vessels , allowing continuous monitoring for threats
Are the immune cells in lymphoid tissues compartmentalised
Yes. T and b cells are activated In different ways. T-cell by APC and B cells by tropic signals.
T and B cells can mix and interact on the edge of T zones in follicles
How do T and B cells find each other in the lymph node
How do T and B cells find each other in the lymph node
Does immunoglobulins on B cells change through differentiation
Immature naive= express mainly IgD and IgM (more M normally). This coexpression is a hall mark of early B cell development
Activated= encounted Ag. Down regulate IgD and expresses other classes eg IgG IgA or IgE
PC= plasma cells. Terminal,y activated. Lost surface expression of IgM and IgD and secrete large amounts of specific immunolglobulins
Memory B cells = activated but haven’t immediately differentiate into B cells- can rapidly respond to subsequent infections
Structure of spleen- where are T and B cells
What are the modes of B cell activation
Phases of 2 and B ell activation
What occurs in germinal centres
Key IS cells that enter and leave spleen
Describe lymphocyte recirculation (eg spleen, blood…)
What regulates lymphocyte passage across high endothelial venules
What regulates lymphocytes leaving blood
Describe how adhesions regulate lymphocyte traffic
3 families of adhesion molecules
Selectins - mediate initial binding of lymphocyte as they move through blood vessel
Integrins- transmembrane protein, help cell-cell and extracellular matrix adhesion.
Ig superfamily- critical for inflammation
Describe how adhesions regulate lymphocyte traffic
4 main steps of lymphocyte migration from blood
Describe T cell adherence in high endothelial venule
How do cells know where to go in lymph node
Name Key structures in intestinal lumen /aka mucosal lymphoid tissue
Name the 4 mucosa associated tissues
