ChiFan_Immunology Flashcards
What are the differences between the innate vs. adaptive immune response?
Innate: Low pathogen specificity, rapid response (min-hours), no immunological memory, less diverse antigens.
Examples: Skin, mucosa, complement system, cells (neutrophil, macrophage, NK cells)
Adaptive: high pathogen specificity, slow response (days) and needs activation by antigens; does have immunological memory; highly diverse antigens.
Examples: T lymphocytes (cell-mediated system), B lymphocytes (humoral system)
What do neutrophils do? How long do neutrophils live?
Phagocytosis, degranulation.
6 hours to a few days.
What do macrophages do? How long do they live?
Phagocytosis, antigen presentation to T cells.
Months to years
What do monocytes do? How long do they live?
Differentiate into macrophage & dendritic cells.
Hours to days
What do eosinophils do? How long do they live?
Degranulation, release of cytokines and enzymes.
8 - 12 days (circulate for 4-5 hours)
What does TLR2 and TLR4 bind to?
What study discusses TLR2 and TLR4 in periodontitis?
TLR2 - Lipoproteins
TLR4 - LPS (lipopolysaccharides)
Mori ‘03 - gene expression levels of TLR2 and TLR4 are significantly higher in patients with periodontal disease than people with healthy periodontium.
Describe the 3 complement cascades
Classical, leptin, alternative pathways
Classical: Ag-Ab complexes –> C1, C4, C2 then the C3 path
Leptin: Lectin binds mannose on pathogens –> MASP’s, C4, C2, then the C3 pathway
Alternative: Pathogens, injured tissue –> C3b, fB, fD, P, then C3 pathway
C3 pathway (shared among all three): C3 –>C3a, C3b opsonizes, C5 –> C5a, C5b attracts C6, C7, C8, C9. These form C5b-9 (the Membrane Attack Complex) –> Cell lysis
Which of the Immune reactions (I, II, III, IV) includes complement?
Type II and III
Describe the types of immune reaction (I, II, III, IV) and examples of each
Type I: Acute. IgE (anaphylaxis, asthma, angioedema)
Type II: Cytotoxic. Complement C3b, IgG/IgM (Goodpasture’s syndrome, hemolytic anemia, erythroblastosus fetalis)
Type III: Immune complex. Complex C3B (arthritis, lupus erythematosus, serum sickness, Arthus reaction, necrotizing vasculitis, etc)
Type IV: Delayed. T cell (tuberculosis, contact dermatitis, graft rejection)
Mnemonics: “ACID” - Acute, Cytotoxic, Immune complex, Delayed
How does smoking affect the immune system response to P. gingivalis?
Smoking suppresses the total production of IgG. (small sample sizes)
What recognizes MHC I and MHC II?
MHC I: Expressed on all nucleated cells in the body; recognized by CD8+ T cells
MHC II: Expressed on APC’s (dendritic cells, macrophages, B cells) and recognized by CD4+ T cells
Compare the Th1, Th2, Th17, and Treg cells ( cytokines, functions, targets and consequences of overactivation).
Th1: IFN-gamma. Function: cell-mediated adaptive immunity. Targets: intracellular pathogens (viruses, bacteria). Overactivation causes delayed-type hypersensitivity and autoimmunity.
Th2: IL-4, IL-5, IL-13. Function: Humoral adaptive immunity. Targets: Extracellular pathogens (parasites, bacteria). Overactivation causes allergies
Th17: IL-17A, IL-17F, IL-21, IL-22. Function: neutrophilic infilammation and innate immunity. Targets: Extracellular pathogens (bacteria, fungi). Overactivation causes inflammation and autoimmunity
Treg: IL-10, TGFß. Function: Immune regulation. Targets: Effector T cells. Overactivation causes immune suppression
What are the five cardinal signs of inflammation?
Calor, Rubor, Tumor, Dolor, Functio laesa
(Heat, redness, swelling, pain, loss of function)
Aspirin irreversibly inhibits which enzyme and pathway?
COX enzyme
Arachidonic acid pathway
