Immunology 4 Flashcards
How does T cell kill each other?
What disorder is this called?
Fas : FasL interaction - pathway
Autoimmune lymphoproliferative syndrome;
CHAI - CTLA4 haplo-insufficiency
LATAIE - LRBA deficiency - decreased CTLA4 expression
Peripheral T cell tolerance mechanisms - 4 types?
- CTLA4/PDL-1
- Anergy ( Only signal 1 )
- Clonal ignorance - ignore low antigen in privileged sites - brain/eye/testis
- Treg cells
T reg cells express what CD?
CD25
IL2R
IL 17 stimulates what and important in pathogenesis of what disease?
IL17 stimulates keratinocytes
IL 17 - psoarisis
Follicular helper T cells secretes what and the function?
IL21 - migrate to lymphoid follicles and help B cell do anything ( affinity maturation, class switching)
Atopic dermatitis has elevated Ig what?
Ig E
Mepolizumab is anti IL5 - so for what asthma?
Omalizumab is anti-IgE - so for what asthma?
Mepolizumab - refractory oesinophilic asthma
Omalizumab - allergic asthma ( IL4 = Ig E mediated)
CD8 cells activated by what cells?
Dendritic cells
Early phase asthma composed of?
Late phase asthma composed of?
Early - vasoactive mediators from mast cells
Late - influx of leucocytes esp. eosinophils ( steroid is good here)
B cells - how it recognises Antigen?
SmIg
HLA I expressed in what cells?
HLA II expressed in what cells?
HLA I = all cells (nucleated cells) except RBC
HLA II = specialised APC
MHC I complex assembled where?
MHC I assembled in golgi
How viruses survive by affecting the MHC I?
- HSV
- Adenovirus
- CMV
HSV = TAP inhibitor protein = Hinders transport of peptides onto MHC
Adenovirus = Anchors MHC in ER
CMV = Chances of binding MHC low - accelerate peptides out of MHC
How cross presentation occurs for CD8 and CD4?
CD8 for EXTERNAL antigen when leaked into cytoplasm
CD4 for INTERNAL antigen when autophagy occurs - peptides is FOREIGN
How cross presentation occurs for CD8 and CD4?
CD8 for EXTERNAL antigen when leaked into cytoplasm
CD4 for INTERNAL antigen when autophagy occurs - peptides is FOREIGN
How HLA causes what transfusion disorder?
Platelet refractoriness
TRALI
Contraindications for immunotherapy?
Malignancy Autoimmune disease Acute illness Asthma + FEV1 < 70% B-blockers
Allergic rhinitis - gold standard test?
Food allergy - gold standard test?
Insect sting - gold standard test?
Anaphylaxis - good test?
Mastocytosis - good test?
Rhinitis = skin prick test = +ve if > 3mm at 15 minutes
food = Oral food challenge
Insect = intradermal test - high sensitivity
anaphylaxis = Serum tryptase levels
Mastocytosis = D816 kit in plasma and BM, serum tryptase > 20
Can mast cell degranulation tells you IgE mediated or non-IgE mediated?
NO
Penicillin has rare cross-sensitivity with cephalosporins - what drug?
1st and 2nd generation cephalosporins
cefaclor and cefalexin
What drug-meds that HIV patient commonly has allergy to?
-for some reason-
Sulfonamides
Chronic idiopathic urticaria - clinical features and tx?
Pruritic hive like lesions - last < 24 hours + intermittent for > 6 weeks
Treatment = Non-sedating anti Histamines H1
2nd line = Omalizumab ( anti IgE)
3rd line = cyclosporin
Roles of steroids in SJS/TEN?
No, referral to burn unit
Treatment of GPA/EPA/Anti-GBM disease/PAN - what’s the common treatment?
PLEX role in ANCA vasculitis?
Induction : Prednisolone and CYP
Maintenance : Prednisolone + RITUX - less relapse
PLEX NO ROLE unless hemoptysis/ lung hemorrhage
Cryoglobulinemia vasculitis types and clinical features?
Type I - all Ig Monoclonal
Type II - all Ig Polyclonal
Type III - all Polyclonal + RF
Acral ischemia ( can be cold induced), Necrotic ulcers
MGUS + Hyper viscosity
Low C4
Kawasaki disease treatment?
Aspirin
IVIG - reduces coronary artery aneurysms
Risk factors of relapse in AAV? - anca a/w Vasculitis?
Young
PR3 - C anca
GPA
chronic nasal carriage of staph aureus
Hyperacute rejection are what mediated?
Acute rejection are what mediated?
Chronic rejection are what mediated?
Hyperacute = Antibody mediated - IgM or antibodies to HLA proteins
Acute - DIRECT allo-recognition
Chronic - INDIRECT allo-recognition ( T cells react to self - but actually foreign HLA)
Hyperacute rejection are what mediated?
Acute rejection are what mediated?
Chronic rejection are what mediated?
Hyperacute = Antibody mediated - IgM or antibodies to HLA proteins
Acute - DIRECT allo-recognition
Chronic - INDIRECT allo-recognition
Hyperacute rejection are what mediated?
Acute rejection are what mediated?
Chronic rejection are what mediated?
Hyperacute = Antibody mediated - IgM or antibodies to HLA proteins
Acute - DIRECT allo-recognition ( Donor HLA antibodies)
Chronic - INDIRECT allo-recognition ( Processed donor proteins)
What is Donor specific antibodies detection vs HLA cross matching?
DSA
- single antigen beads attach to specific HLA antigen OF PATIENT”S SERUM- then fluorescent dye come bind that beads
- then machine detects the light from fluorescent
Cross matching ( flow cytometry)
- DONOR LYMPOCYTES -throw into recipient serum
- if binding of recipient antibodies to DONOR LYMPHOCYTES = hyperacute rejection
