Immuno Flashcards
Lymph drainage of anal canal above pectinate line, bladder, middle third vagina, cervix and prostate
Internal iliac
Lymph drainage of testes, ovaries, kidneys and uterus
Para-aortic
Lymph drainage of anal canal below pictinate line, skin below umbilicus, scrotum and vulva
Superficial inguinal
Right lymphatic duct drains into
right side of body above diaphragm
Thoracic duct drains into which veins
left subclavian and internal jugular
Why does splenic dysfunction or asplenia increase risk of infection by encapsulated organisms
decreased IgM, decreased complement activation (C3b opsonization)
Where does APC between macrophages and B cells occur in the spleen?
Marginal zone (between red pulp and white pulp)
Where are T cells found in the spleen?
PALS (periarteriolar lymphatic sheath within white pulp)
Where are B cells found in spleen?
In follicles within white pulp
In which two conditions is thymus hypoplastic?
DiGeorge (loss of 3rd pharyngeal pouch) and SCID
In which condition is thymus enlarged
Myasthenia gravis
What are the three loci that encode MHCII
HLA-DP, HLA-DQ, HLA-DR
What are the three loci that encode MHC I
HLA-A, HLA-B, HLA-C
Peptide loading onto MHC in RER after delivery via TAP is mechanism for which MHC molecule
MHC I
Antigen loading following release of invariant chain in acidified endosome (lysosome) is which MHC mechanism
MHC II
How do NK cells kill virally infected cells and tumor cells
Induce apoptosis via perforin and granzyme
What induces NK cell killing?
Exposure to nonspecific antigen signal or absence of MHC I on target cell surface
Which signal activates antibody-dependent cell-mediated cytotoxicity in NK cell?
CD16 binding Fc region of bound Ig
IL-2, IL-12, IFN-alpha and IFN-beta enhance activity of which immune cell
NK cell
HLA B27 type diseases
PAIR (non-RF arthritis): Psoriatic, Ankylosing spondylitis, IBD-associated arthritis, Reactive arthritis
HLA DQ2/DQ8
Celiac disease
HLA DR-4
Rheumatoid arthritis
HLA-DR3
Diabetes mellitus type 1, SLE, Graves, Hashimoto’s thyroiditis, Addison (hormonal diseases)
HLA-DR5
Hashimoto, Pernicious anemia (B12 deficiency)
3 ways antibody generates antigen-independent diversity
- VDJ (heavy chain) and VJ (light chain) recominbation
- Random addition of nucleotides by TdT
- Random combination of heavy chains with light chains
2 mechanisms of antigen-dependent antibody specificity generation
- Somatic hypermutation and affinity maturation of variable region (Fab)
- Isotype switching of constant region (Fc)
Three ways antibodies mediate immunity
- Opsonization (promote phagocytosis)
- Neutralization (prevent bacterial adherence)
- Complement activation (enhance opsonization and lysis via MAC)
why do bacterial vaccines typically require boosters and adjuvants?
They lack antigens with a peptide component so can’t bind MHC and induce thymus-dependent immune response (weakly immunogenic)
Formation of memory cells requires a thymic-dependent immune response. This is typically done for which type of antigen
Peptides presented on MHC molecules
What is C-reactive protein
Measurement of ongoing inflammation, induces complement
Why is ferritin activated in immune response
Sequesters iron so microbes cant use it
Why is albumin downregulated in illness
reduction conserves amino acids for positive reactants
Why is transferrin reduced in immune response
Sequesters iron by macrophage
What causes amyloidosis in chronic illness
elevated serum amyloid A
Function of hepcidin
decrease iron absorption by degrading ferroportin and decreasing iron release from macrophage
Which cytokine stimulates acute phase reactants?
IL-6
Where are complement proteins synthesized
Liver
Function of C3b
Opsonization and help clear immune complexes
Function of C3a, C4a, C5a
anaphylaxis
Function of C5a
neutrophil chemotaxis
Function of C5b-C9
MAC cytolysis
Which enzyme is deficiency in heriditary angioedema
C1 esterase (ACE inhibitors contraindicated)
Severe recurrent pyogenic sinus and URI infections, increased susceptibility to type III HS reactions due to
C3 deficiency
List the two types of C3 convertase
C4b2B (Classic and Lectin pathways) or C3bBb (Alternate)