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
How does CD8 kill?
Either perforin/granzyme B
or Fas L
Who does NK cell kill?
What activates it?
What does it secrete?
Cells not showing MHC I (good b/c cancer or infected cells may hide it)
IL 12, 2, IFN alpha and beta (all released in viral infection)
Secretes IFN-gamma (not surprising as it activates macrophage)
What does CD 16 do?
NK cell marker and binds Fc of Ig to activate it and kill for Antibody Dependent Cell Mediated Cytotoxicity
some macrophage and neurtophils have it
5 surface markers of b cells? (what are the 2 bonus markers not specific for b cells?)
19 20 21 IgM IgD
APC cells so B7 and MHC2, CD40
What is CD14?
Macrophage marker (also have MHC II, B7 and CD40 to be more sensitive to IFN gamma)
Binds to LPS of gram negative bacteria so they make acute phase cytokines: IL-1, 6 and TNF-alpha
Idiotype vs isotype?
Idiotype is what specific binding there is
Isotype is Fc types (IgM, IgD, IgE, IgA, IgE)
Why do we care about kappa and lambda?
Normally kappa:lambda is 2:1, if it is thrown wayyyy off suspect neoplasm (Mult myel)
Summarize the important sites, and proteins for variation creation in receptors?
VDJ unites in DNA have Recombination sequences around them that can be cut by recombination activating gene complex.
No B or T cell deco if it is off the rag
IgG does what? What is significance of half life?
It is the prototypical antibody
Fixes complement
Crosses placenta
Opsonize bacteria
Passive immune system from mom lasts about a mont b/c thats a half life
What does IgE bind to
Allergen and hits mast cells and basophils to attack worms by activating eosinophils.
Passive vs active immunity? When do you give one of them?
Passive is giving preformed antibodies (3 week half-life) and happens with IgA in breast milk, IgG from placenta, antitoxin or humanized antibody
Active is exposure and letting blody learn it
To Be Healed Rapidly
Tetanus, Botulism, HBV, Rabies (RSV in premies with pavilizumab)
What is pavilizumab?
Anti RSV. Give to premature babies who you don’t want to get severe resp infection.
What is difference between response from live attenuated vaccine vs inactivated or kileld?
Live attenuated gets a small population of cells infected so you can mount a CELLULAR response (strong and no booster needed)
Killed is cells making humoral response (weaker and usually needs booster)
Where are live attenuated contraindicated? Exceptions?
Pregnant and immunocompromised
But IF HIV IS OVER over 200, MMR, Varicella and Yellow fever benefit outweighs risk b/c can mount some response.
Egg based vaccine?
Influenza. Yellow fever
What is a thymus independent antigen? What is an example? Outcome?
Thymus independent are antigen lacking peptide component can’t be presented by MHC. Nonimmunigenic or weakly immunogenic.
Vaccines often need boosters (example is pneumococcal polysaccharide vaccine)
Thymus dependent antigen?
Protein component like diphtheria so class switching and memory happens b/c B cells with Th receptor and CD40 interaction to make them go nuts and strong response!
AL amyloidosis?
L for Light chains of Ig. Plasma cell disorder
AA amyloidosis (secondary)?
Secondary amyloids from chronic conditions like rh arthritis, IBD, spondyloid. Amyloid A is where it got its name.
Amyloidosis causes what in heart?
Thickening of heart: CHF or affect conduction: arrhythmia
amyloidosis causes what in kidney?
Nephrotic syndrome, failure
amyloidosis causes what in blood vessels?
Issues.
What amyloid causes alzheimer?
Amyloid Beta protein cleaved from amyloid precursor protein
What is Islet amyloid polypeptide?
Type 2 diabetes deposits amylin in pancreas (b/c islet cells in overdrive lots of amylin is kicked out)
What is dialysis related amyloid?
Beta2 microglobulin on dialysis may have carpal tunnel syndrome
What is serum sickness?
III hypersensitivity against happen (drugs)
Fever, urticaria, arthralgia, proteinuria, lymphadenopathy
What is arthus reaction?
Subacute antibody mediated hypesensitivity III reaction.
Intradermal injection of antigen causes antibodies to make antigen complex in skin
Edema, necrosis and activation of complement
3 mechanism of type II hypersensitivity?
Antibodies against cells
1 Opsonization causing phagocytosis or complement ctivation
2 Complement mediated lysis
Antibody depnent cytotoxicity
3 NK Cells with CD 16
What are three pathways of complement and what activates them?
Classic pathway: IgG or IgM antigen and then C1 complement
Alternative: spontaneously activating by molecules on surface of invading microbes
Lectin pathway: MAnnose-binding lectin binds mannose on surface of microbe
What is starting point for classic pathway?
What blocks it?
C1 inhibitor inhibits cleavage of C1 into active components
AKA C1 esterase inhibitor
What is end product of complement? What makes it up?
Membrane attack complement.
C5b, 6, 7, 8, 9, 9, 9, 9
What complement is opsonization?
C3b
What complement parts cause anaphylaxis?
C3a (mast and basophils)
C5a (neutrophil chemotaxis)
Deficiency in C1 esterase inhibitor? What is contraindicated?
Hereditary angiodema (bradykinin is up_ unknown mechanism. ACE is contraindicated
C3 deficiency causes what? What weird thing but understandable thing are you more susceptible to?
recurrent pyogenic sinus infections and resp infectin
Strep pneumo
H influ
More susceptible to Type III hypersenstivity (not being phagocytksed b/c no opsonization)
Deficiency in MAC?
Neisseria bacteremia risk (both gonoccal and meningocacal)
Deficiency of DAF (decay accelerating factor)?
Unable to protect self from alternate pathway.
Complete mediated lysis of RBCs and paroxysmal nocturnal hemoglobinuria
What causes paroxysmal nocturnal hemoglobinuria?
How do you Dx?
Deficiency in glycolphosphatidylinositol so no DAF attachment and susceptible RBC to alternative complement pathway
Hemosidourea Thrombosis (b/c platelets destroyed and release factors)
Dx: Ham’s Test: if lyse in acid, it is positive
Flow cytometry for CD 55
Tx for paroxysmal nocturnal hemoglobinuria?
Eculizumab: inhibits complement
Transfusions (duh)
Warfarin (duh b/c thrombosis)
What are functions of spleen?
Macrophage remove RBC and encapsulated bacteria
STORES PLATELETS and RBC so splenomegaly: thromboctopenia
Eosinophilia is caused by what?
NAACP
Neoplsm Asthma/allergies (sturge strauss) Adrenal insufficiency Collagen vascular disease (Polyarteritis nadosa, dermatosytisi) Parasites
What is there to know about mast cells? 3 things
Histamine in it
Found in tissues
Cromolyn prevents degranulation
IL mnemonic
Hot TBone stEAK
fever T cells Bone marrow igG and igg production igA and eosinophils (its snotty) aKute proteins
What 5 things does a macrophage secrete?
IL 1, 6
TNF-alpha septic shock and leukocyte attractor
IL-8 MAJOR NEUTROPHIL chemotactic factor
IL 12 more Th1 and NK activation
Neutrophil chemotactic agents?
IL-8, C5a, Leukotriene B4
What is aldesleukin?
recombinant IL-2 (more t cells
Metastatic melanoma and renal cell carcinoma
GMCSF activates bone marrow. What are drugs?
FilGRASTIM, sanGRAnoSTIM (GRA and stim)
What is an IL11 derivative used for? What is its name?
Oprelvekin (oprELEVINkin)
Thrombocytopenia
What is IFNalpha given for?
Tough viruses to get rid of and
Kaposi sarcoma
Hairy cell leukemia
Melanoma
What is IFNbeta given for?
multiple sclerosis (weird right?)
What is IFNgamma given for?
Chronic granulomatous disease when no NADPH oxidase
