Immunology Flashcards
What is the most common subclass of IgG? Which IgG subclass best recognizes polysaccharide antigens?
IgG1 = most common subclass (66%); IgG2 = 23%, IgG3 = 7%, IgG4 = 4%
All subclasses involved important for defence against bacteria and viruses via neutralization (toxins + viruses, opsonisation, complement activation, NK cells).
IgG2 best recognizes polysaccharide antigens.
What is the name of the receptor that IgE binds? Which cells is it found on?
FC epsilon receptor 1
Mast cells, basophils, eosinophils
What is the function of IgA?
Found on mucosal surfaces.
Inhibits pathogenic colonization of mucosal surgaces, tissues, binds to mucus and traps surfaces, inhibits penetration of bacterial toxins
What is the most common immunglobulin isotype?
IgA
Complement studies in acquired vs hereditary angioedema?
Acquired:
Low-normal C1INH, low C1q
Low = type 1, normal = type 2
HAE 1:
low C1INH
normal C1q
HAE2:
normal C1INH, abnormal functional studies
normal C1q
All - low C4, C2, normal C3
Negative acute phase proteins (decrease in inflammation)
ATTTRA albumin transferrin transthyretin transcortin retinol-binding protein antithrombin
Acute phase proteins (increase in inflammation)?
Which cytokines stimulate their release/formation?
Amyloid A Alpha 2-macroglobulin C-reactive protein Ceruloplasmin Complement factors Ferritin Mannose-binding protein Haptoglobin Serpins
Inflammatory interleukins - IL-1, IL-6, IL-8, and TNF-α, released from neutrophils, granulocytes and macrophages .
HLA associated with:
- RA
- SLE
- Ank spond
HLA-DR3 = SLE, myasthenia, graves, T1DM, addisons
HLA-DR4 = RA
HLA-B27 = ank spond
Th1 cells:
- differentiate under influence of which cytokines?
- what cytokines do they release?
- what is their major role?
Differentiate under influence of IFN-y, IL-12
Secrete IFN-Y, TNF-a
Role - defense against intracellular infections (inc. TB, mycobacteria)
Th17 cells:
- differentiate under influence of which cytokines?
- what cytokines do they release?
- what is their major role?
Differentiate under influence of TGF-b, IL-6, IL-1 (reinforced by IL-23)
Secrete IL-17, IL-22
Role - defense against fungi + staph; pro-inflammatory (sitmulate release of IL-16, TNF, G-CSF, GM-CSF); role in psoriasis; recruitment of neutrophils
Th2 cells
- differentiate under influence of which cytokines?
- what cytokines do they release?
- what is their major role?
Differentiate under influence of IL-4
Secrete IL-4, IL-5, IL-13 (allergy cytokines)
Role - allegy; atopic responses; defence against helminths
Treg cells
- differentiate under influence of which cytokines?
- what cytokines do they release?
- what is their major role?
Differentiate under influence of TGF-beta
Secrete IL-10, TGF-Beta
Role - immune regulation (inhbitory)
T follicular cells
- what cytokines do they release?
- what is their major role?
Secrete IL-21 Role - B cell help (class switching, affinity mautiation)
Which cell surface protein does memory T lymphocytes express?
CD45Ro
Major roles of CRP
Promotes recognition and elimination of pathogens (can bind to Fc receptors on phagocytic cells)
Enhances clearance of necrotic apoptotic cells
Complement system activation via C1q binding (binds to phosphocholine residues on bacterial polysaccharides)
Induction of inflammatory cytokines and tissue factor
