6/28 - Diseases of Immune System Flashcards
immune reactant for Type II HS
IgG and some cases IgM
antigen for Type II HS
cellular or extracellular matrix antigens
what causes type II HS? what does it result in?
cause: destruction of cells
result: inflammation or interference w/ normal cell function (dysfunction)
mechanisms of type II HS
- opsonization and phagocytosis (destruction)
- inflammation (destruction)
- cellular dysfunction
describe opsonization and phagocytosis in type II HS
antibody coats cell and and is marked for phagocytosis
what causes tissue damage in type II HS
cellular lysis induced by direct binding of antibody to cell surface antigens
what do antibodies attack in inflammation of type II HS
attack leukocytes or RBCs (mobile cells) or bind to fixed cells (part of solid tissues)
what do antibodies involved in inflammation activate? what does this result in
activate complement generating by-products , including chemotactic agents (mainly C5a)
this directs migration of neutrophils and monocytes and anaphylaxtonins
what are the anaphylatoxins? what does it do?
C3a, C4a, and C5a
increase vascular permeability
pathway for type II HS inflammation and tissue injury
- antigen + target cell + antibody
- complement protein (C3a and mainly C5a)
3a. complement 5b-9MAC
3b. + membrane attack complex (MAC) insert into cell
4b. results in osmotic lysis or drill holes in cell membrane
- complement protein (C3a and mainly C5a)
2 main examples of antibody-mediated cellular destruction. what type of HS?
- autoimmune hemolytic anemia
- erythroblastosis fetalis (hemolytic disease of newborn)
both type II
what is the disease where individuals produce antibodies to their own blood? HS type?
autoimmune hemolytic anemia - type II
what is the disease where there is an antigenic difference between mother and fetus and IgG antierythrocyte antibodies from the mother cross the placenta and destroy the fetal red cells? HS type?
erythroblastosis fetalis - type II
what are the two main examples of cellular dysfunction for type II HS
- myasthenia gravis (interferes w/ cellular function)
- grave’s disease (cellular hyperfunction)
what disease:
antibodies reactive with Ach receptors in motor end plates of skeletal muscles block neuromuscular transmission and cause muscle weakness? what type of HS
myasthenia gravis - type II HS
what disease:
antibody-mediated stimulation of cell function is the basis; antibodies against the TSH receptors on thyroid epithelial ells stimulate the cells, resulting in hyperthyroidism
what type of HS
Grave’s disease = type II HS
autoimmune hemolytic anemia
target antigen, mechanism of disease, clinical manifestation, HS type
TA: red cell membrane protein
MoD: opsonization and phagocytosis of RBCs
CM: hemolysis anemia
HS: type II
autoimmune thrombolytic purpura
target antigen, mechanism of disease, clinical manifestation, HS type
TA: platelet membrane protein
MoD: opsonization and phagocytosis of platelets
CM: bleeding
HS: type II
B)
pemphigus vulgaris
target antigen, mechanism of disease, clinical manifestation, HS type
TA: protein in intercellular junctions
MoD: antibody-mediated activation of proteases disruption of intercellular adhesion
CM: skin vesicles
HS: type II
vasculitis caused by antineutrophil cytoplasmic AB
target antigen, mechanism of disease, clinical manifestation
TA: neutrophil granule proteins released from activated neutrophils
MoD: neutrophil degranulation and inflammation
CM: vasculitis
HS: type II
good pasture syndrome
target antigen, mechanism of disease, clinical manifestation, HS type
TA: non collagenous protein in BM of kidneys
MoD: complement and Fc receptor mediated inflammation
CM: nephritis, lung hemorrhage
HS: type II
acute rheumatic fever
target antigen, mechanism of disease, clinical manifestation, HS
TA: streptococcal cell wall antigen, antibody-cross react w/ myocardial antigens
MoD: inflammation, macrophage activation
CM: myocarditis, arthritis
HS: type II
myasthenia gravis
target antigen, mechanism of disease, clinical manifestation, HS type
TA: Ach receptors
MoD: antibody inhibits acetylcholine binding, down modulates receptors
CM: muscle weakness, paralysis
HS: type II
insulin-resistant diabetes
target antigen, mechanism of disease, clinical manifestation, HS type
TA: insulin receptor
MoD: antibody inhibits binding to insulin
CM: hyperglycemia, ketoacidosis
HS: type II
graves disease
target antigen, mechanism of disease, clinical manifestation, HS type
TA: TSH receptors
MoD: antibody mediated stimulation of TSH receptors
CM: hyperthyroidism
HS: type II
pernicious anemia
target antigen, mechanism of disease, clinical manifestation, HS type
TA: intrinsic factor of gastric parietal cells
MoD: neutralizatin of intrinsic factor, decreased absorption of Vit B
CM: abnormal erythropoiesis anemia
HS: type II
immune reactant for type III HS
IgG or IgM
antigen for type III HS
solubule antigen
type III HS rxn is mediated by formation of what
antigen-antibody aggregates called immune complexes
how are type III HS rxns frequently initiated
when antigens combine with antibodies in circulation (creating immune complexes)
how are type III HS rxns less frequently initiated
when immune complexes are formed at sites where antigen has been “planted” previously
type III HS immune complexes can precipitate in various tissues (such as skin, joints, vessels, or glomeruli) resulting in what?
tissue damage and inflammation at the site of deposition thru triggering of classical complement pathway
in type III HS rxn, antigens may form immune complexes that are [exogenous OR endogenous]
BOTH! exogenous AND endogenous
what is a foreign protein that is injected or produced by an infectious microbe
exogenous rxns
what are self antigens/autoimmuniy?
endogenous rxns
what is an acute, localized inflammatory response that typically occurs after vaccination? type of HS
acute Arthus rxns - type III
what mediates acute Arthus rxns?
antigen is injected or enters intradermally or subcutaneously, they bind w/ antibody to form localized immune complexes
when do acute arthus rxn form
within 4-8 hours
as acute arthus rxn develops, localized tissue damage and vascular damage results in what?
accumulation of fluids (edema) and RBCs (erythema) at site of antigen entry
what disease: large amounts of antigen enter blood stream (vaccinations of multiple insect bites) and bind to antibody, circulating immune complex forms? type of HS
serum sickness - type III
what disease involve immune complexes that are smaller and soluble and not phagocytosed by phagocytic cells leading to abnormal immune rxn? type of HS
serum sickness - type III
manifestation of serum sickness depends on what
- quantity of immune complex
- overall site of deposition
- accumulation of complexes occurring at site of blood filtration
generalized type III HS rxn at different site results in what?
different diseases:
1. glomerulonephritis - kidney
2. vasculitis - arteries
3. arthritis - synovial joints
systemic lupus erythematosus
antigen involved, clinical manifestation, and HS type
AI: nuclear antigen (circulated or planted in kidney)
CM: nephritis, skin lesions, arthritis others
HS: III
poststreptococcal glomerulonephritis
antigen involved, clinical manifestation, and HS type
AI: streptococcal cell wall antigens; may be planted in glomerular basement membrane
CM: nephritis
HS: III
polyarteritis nodosa
antigen involved, clinical manifestation, and HS type
AI: hep B virus antigen in some cases
CM: systemic vasculitis
HS: III
reactive arthritis
antigen involved, clinical manifestation, and HS type
AI: bacterial antigens
CM: acute arthritis
HS: III
serum sickness
antigen involved, clinical manifestation, and HS type
AI: various proteins (e.g. foreign serum protein)
CM: arthritis, vasculitis, nephritis
HS: III
arthus rxn
antigen involved, clinical manifestation, and HS type
AI: various foreign proteins
CM: cutaneous vasculitis
HS: III
!
what HS is cell-mediated delayed rxn
type IV
type IV HS invovles interaction of what cells
T cells, monocytes, and macrophages
type IV rxn is also called what
delayed-type HS
how long does it take for type IV to develop
several days
what rnx is mediated by T cells that provoke inflmamatory rxn against exogenous or endogenous antigens
type IV
what HS rxn can occur in response to contact w/ certain allergens (contact dermatitis) or in response to some diagnostic procedures as in the tuberculin skin test
type IV HS
pathway of type IV HS rxn
- activated CD4+ T h1 cells recognized foreign antigen in complex w/ MHC class II on surface of antigen presenting cells
- secrete: IL2 & interferon gamma thus mediatin immune response
do activated CD8+ T cells destroy target cells on contact
YES
activated macrophages produce hydrolytic enzymes and on presentation w/ certain intracellular pathogens, transform into what?
multinucleated giant cells
what is also known as purified protein derivative
tuberculin
what is a combination of proteins that are used in the diagnosis of TB
tuberculin
when is TB test considered positive
after 48-72 hours, if there is more than 5-10 mm area of swelling
microscopically, what is causing TB test to be positive
CD4+, TH1 cells secrete cytokines (most importantly INF-gamma) causing vascular leakage leading to edema and fibrin deposition
with persistent or nondegradable antigens colonizing the lungs or other tissues, the infiltration in TB is dominated by ___ over a period of 2-3 weeks
macrophages
dominated macrophages in TB undergo transformation into ___
epithelioid cells
what is a microscopic aggregation of epithelioid cells, usually surrounded by a collar of lymphocytes
granuloma/granulomatous inflammation
B!
what are the clinical conditions which granulomas are formed
- myobacteria tuberculosis
- deep fungal infections
- parasitic infections
- foreign bodies
what results from the contact of an offending chemical or antigen w/ the skin, and the subsequent T-cell mediated response
allergic contact dermatitis
what is an inflammatory disease of the skin
allergic contact dermatitis
what are the best indicators of the offending agent in ACD
morphology and location of the dermatitis
what is a common cause of ACD and presents as linear streaks where the plant encounters the skin
poison ivy
what is a common cause of ACD and presents as dermatitis where necklaces and earrings containing this are worn
nickel
what is a common cause of CHRONIC dermatitis
rubber glvoes
what cells mediate ACD
CD8+ T cells
where are ACD CD8+ T cells primed? recruited?
primed: lymphoid organs during sensitization phase
recruited: into the skin upon exposure to antigen
rheumatoid arthritis
specificity of pathogenic T cells, mechanism of tissue injury, clinical manifestation, and HS type
specificity: collagen, citrullinated self-protein
MoT: inflammation mediated by cytokines, role of antibodies and immune complexes?
CM: chronic arthritis w/ inflammation, destruction of articular cartilage
HS: III
multiple sclerosis
specificity of pathogenic T cells, mechanism of tissue injury, clinical manifestation, and HS type
specificity: protein antigen in myelin sheath
MoT: inflammation mediated by cytokines, myeline destruction by activated macrophages
CM: demylenination in CNS w/ perivascular inflammation; paralysis
HS: IV
type I DM
specificity of pathogenic T cells, mechanism of tissue injury, clinical manifestation, and HS type
specificity: antigen of pancreatic islet of beta cell
MoT: t cell mediated inflammation; destruction of islet cells by CTLs (CD8 T lymphocytes??)
CM: chronic inflammation of islets, destruction of beta cells, diabetes
HS: IV
inflammatory bowel disease
specificity of pathogenic T cells, mechanism of tissue injury, clinical manifestation, and HS type
specificity: enteric bacteria, self antigens?
MoT: inflammation by cytokines
CM: chronic intesetinal inflammation
HS: IV
psoriasis
specificity of pathogenic T cells, mechanism of tissue injury, clinical manifestation, and HS type
specificity: unkown
MoT: inflammation mediated by cytokines
CM: destructive plaques in the skin
HS: IV
contact dermatitis
specificity of pathogenic T cells, mechanism of tissue injury, clinical manifestation, and HS type
specificity: various environmental chemicals (uroshiol from poison ivy or poison oak)
MoT: inflammation mediated by cytokines
CM: epidermal necrosis, dermal inflammation, causing skin rash and blisters
HS: IV