Hypersensitivity and autoimmune disease Flashcards
Types of hypersensitivity
Immediate (type 1)
Antibody-mediated (type II)
Immune complex-mediated (type III)
Delayed-type hypersensitivity (type IV)
Immune mechanism of type I hypersensitivity
Activation ot Th2 cells resulting in the production of IgE which in turn binds to FCER on mast cell, basophils and eosinophils
Immune mechanism of type II hypersensitivity
IgM and IgG against surface
Immune mechanism of type III hypersensitivity
Deposition of immune complexes comprised of IgM or IgG and soluble antigen
Immune mechanism of type IV hypersensitivity
Inflammatory cytokines, IFN-Y and IL-17, produced by CD4+ Th1 and Th17 cells
Mechanisms of tissue injury in type I hypersentivity
Immediate reaction - degranulation and release of vasoactive amines and proteases
Late-phase reaction - Synthesis and secretion of prostaglandins and leukotrienes
cytokine-induce inflammation and leukocyte recruitment
Mechanisms of tissue injury in type II hypersensitivity
Opsonization and enhaces phagocytosis
recruitment and activation of inflammatory cells
Mechanisms of tissue injury in type IV hypersensitivity
IFN-y activation of macrophage
IL-17 recruitment and activation of neutrophil
CTL-mediated cellular death
Only hypersensitivity mediated by IgE
Type I
Mast cell mediators - Mediators stored and released
histamine
heparin
eosinophil chemotactic factor A
Mediators newly synthesized from arachidonic acid
prostaglandin D2, E2, F2a
Leukotrienes C4, D4, E4 (lipoxygenase pathway)
Leukotriene B4
Target antigen of acute rheumatic fever
streptococcal cell-wall Ag; Ab cross-reacts with myocardial Ag
Target antigen for Goodpasture syndrome
Type IV collagen in basement membranes of kidney glomeruli and lung alveoli
Target antigen in transfusion reaction
ABO blood glycoproteins
Target antigen for myasthenia gravis
Acetylcholine receptor
Target antigen for Graves disease
TSH receptor
Target antigen for pernicious anemia
instrinsic factor of gastric parietal cells
Type of hypersensitivity of HDNB
type II
Antigen involved in systemic lupus erythematosus
dsDNA, Sm, other nucleo-proteins
Clinical manifestations of systemic lupus erythematosus
nephritis, arthritis, vasculitis, butterfly facial rash
Antigen involved in poststreptococcal glomerulonephritis
streptococcal cell wall Ags
HLA genes
Among the strongest genetic associations with the development of autoimmmune disease
HLA allele for rheumatoid arthritis
DR4
HLA allele for insulin-dependent diabetes mellitus
DR3/DR4
HLA allele for multiple sclerosis, goodpasture’s
DR2
HLA allele for systemic lupus erythematosus
DR2/DR3
HLA allele for celiac disease
DQ2 or DQ8
HLA allele for Graves disease
B8
HLA allele for ankylosing spondylitis, psoriasis, inflammatory bowel disease, reactive arthritis
B27
Infection with what is at the highest risk for Guillain-Barré syndrome?
Campylobacter
