DIT immunology Flashcards
Where are B cells in lymph node?
Follicles
Where are T cells in lymph nodes?
Paracortex (big if viral infection, small if DiGeorge)
What is in the medulla of lymph nodes?
Plasma cells are in the cords and in the sinus between the cords there are macrophage
Where are lymph follicles in intestine?
MALT mucosa associaed lympatic tissue (aka GALT)
Peyer’s patch in Ileum!!! Unencapsulated (how to tell ileum)
In lamina propria of ileum
lymphatics drain to this place if they are from arm and lateral breast
axillary (check with breast exam)
lymphatics drain to this place if they are from lateral dorsal foot?
popliteal
lymphatics drain to this place if they are from thighs
superficial inguinal
lymphatics drain to this place if they are from GI
Stomach: celiac (matches blood supply)
Duodenum and jejunum: superior mesenteric
Sigmoid colon is inferior mesenteric
lower rectum internal iliac
Below pectinate line: superficial inguinal nodes
lymphatics drain to this place if they are from testes?
Para-aortic (b/c fundamentally not external)
lymphatics drain to this place if they are from scrotum
Superficial inguinal node (like other superficial stuff down there)
right arm and right head drains to lymph where?
Right lymphatic duct. Obstruction causes non-pitting edema
The rest of the body drains into what (lymph from not right arm or right face)
Thoracic duct: Subclavian and internal jugular junction
Where are peyer’s patches?
ileum in lamina propria
What is CD3?
is a marker for all T cells and associated with TCR
What does CD4 do?
Binds MHCII and CD4 and CD3 can work together to activate if TCR matchtoo
What does CD8?
Recognizes MHCI which is on all cells (except RBC) and when weird thing is expressed to surface, a TCR may recognize it
What genes make up MHCI?
HLA A, HLA B and HLA C (no D, D is for the MHC II stuff!)
What genes make up MHCII?
HLA DR, DQ and DP
HLA B27 is a gene for what? What is associated with it?
MHC I (recognizing Self)
PAIR Psoriatic arthritis Ankylosing spondylitis IBD Reactive Arhtritis
HLA DR3/DR4 is associated with what? What are they genes for?
They are for MHC II.
Is associated with Diabetes M I (also DR4 is rheumatoid arthritis)
What is B7? CD80/86
On macrophage: binds to T cell proteins to increase signal (binds CD28)
What is CD40?
On antigen presenting cells to further activate APC (so cells show off more!).
What is langerhan cell histiocytosis? What is marker?
What will you see on Step 1?
Excess proliferation of langahan cells (dendritic cell in epidermis). Causes lytic lesion or rash or otitis media with mastoid bone
Marker is S-100 and CD1a
Step 1 will have Birbeck granules (Granules look like tennis rackets pg 396)
What are 3 cell types to present antigen?
Dendritic
B cell
Macrophage
What happens in cortex of thymus?
positive selection. T cells posive for both CD4 and 8 (same cell) bounce until match MHC just right (not to tight or too lose, or they will die) to graduate to medulla
They will lose marker (either CD4 or 8) that doesn’t fit and advance
Th1 vs Th2?
Th1 stimulate macrophage and CD8 (IL 2 and IFN gamma)
Th2 stim plasma cells to make antibodies. IL 2, 4, 5 and IL 10
When naive T cell is exposed to IL-12 what happens?
What will it secrete?
IL-12 turns it into Th1 cell
It will secrete IL-2 to create more T cells
It will secrete IFN gamma which activates macrophage and stops Th2 production
What does IL-10 do?
inhibits Th0 from turning into Th1
When Th0 is hit by IL-4, what happens?
What will t cell then secrete?
IL-4 turns it into Th2
IL-2 to make more T cells
IL 4 Th2 production and b cell
IL 5 b cell activation
IL 10 will block Th1 production
KNOW THAT
T cell activation?
TCR and CD4 or 8 complex then CD28 recognizes B7 for cosignal
What does IL-2 do?
More T cell production
B cell activation?
BCR takes in antigen, then it is presented on MHC II to Th2 TCR
CD40 on B cell binds CD40 ligand for costim signal
Th2 secretes IL-4 and 5 so immunoglobulins happen
IL 2? IL 4 IL 5 IL10 IL 12 IFN gamma
All pg 200
2: proliferation of T cells 4 B cell prolif. Th0->Th2 5 B cell prolif 10 is less Th1 and macrophage 12 more Th1 IFN gamma is less Th2 and more macrophage
Th 1: IL2 and IFN gamma
Th2: IL2, 4, 5, 10
Il 12 from macrophage/dendritic