Immunology Flashcards
(33 cards)
HLA class 1 presents to
CD8 - cytotoxic T cells
HLA class 2 presents to
CD4 - helper T cells
hypersensivity
immune response is exaggerated or inappropriate to harmless environmental antigens
Ab in type 1 hypersensitivity, also called?
IgE
also called allergy and atopy
allergy is a result of
end result of complex interplay of a number of factors - atopy, environment, immune reactivity
pathogenesis of allergy
mast cells + IgE - stimulate mediators to cause secretions, vasodilation, mucosal oedema
diagnosis of allergy
hx , ex, skin prick tests
IgE (RAST test)
type 2 hypersensitivity
IgG.or IgM
self or exogenous stimulator
examples of type 2 self hypersensitivity
graves
myasthenia gravis
goodpastures
examples of type 2 exogenous hypersensitivity
blood transfusion - haemolytic reaction
HDN
hyper acute graft rejection
type 3 hypersensitivity
antibody antigen complex disposition in tissues = immune complex recruits inflammatory cells - tissue damage
two outcomes from hypersensitivity type 3
serum sickness
arthrus reaction
serum sickness?
systemic illness where immune complexes form in the circulation and are deposited in a widespread fashion throughout many tissues
arthrus reaction
a more localised disorder where complexes are actually formed locally in tissues rather being deposited from the blood
e.g. of Hypersensitivity 3
EAA
post strep GN
SLE
type IV hypersensitivity mediated by
T helper cell mediated and its cytokine products IL2 , gamma interferon
type 4 examples
Mantoux test
contact dermatitis
autoimmunity due to
loss of tolerance - therefore autoreactive T and B cells are able to mature
primary defects of innate immunity
chronic granulomatous disease: problem with intracellular killing
leucocyte adhesion def (LAD): neutrophils unable to attach to endothelium
complement deficiencies?
C1-c4?
C3?
C5-C9?
C1-C4: immune complex disease, infection (strep, haemophilia, meningococcus)
C3: recurrent above infections
C5-C9: recurrent neisserial infection
hereditary angioedema
similar presentation to anaphylaxis - but not itchy, or painful
deficiency of C1 inhibitor (control protein)
tx - infusion of C1 inhibitor
SCID?
severe combined immune deficiency
dysfunction with T AND B cells
SCID pc?
well for first 3 months
persistent superficial candida
diarrhoea and failure to thrive
then cross line –> chronic bronchitis, interstitial pneumonitis, bacterial seps
TX for SCID
supportive until suitable bone marrow donor
earlier the better
