Immunology Flashcards
(24 cards)
Describe the pathophysiology of a type I hypersensitivity reaction
Allergy/asthma
- The antigen binds to IgE antibody on mast cells
- Triggers release of histamine causing inflamamtion
Describe the pathophysiology of type IV hypersensitivity reaction
Contact dermatitis/organ rejection
- CD4 T cells recognise cellular antigens, activating phagocytes
- Cell mediated cytotoxicity
What activates the complement pathway?
IgM and IgG forming antibody-antigen complexes
What antibody is found in breast milk?
IgA
What is the role of helper T (CD4) cells?
Cell mediated response:
- Produces IL-2
What is the role of cytotoxic (CD8) cells?
Cell mediated response:
- Induced apoptosis in tumour and virally infected cells
What is the role of cytotoxic (CD8) cells?
Cell mediated response:
- Induced apoptosis in tumour and virally infected cells
What is the role of B cells?
Antigen presenting cell
What is the role of a plasma cell?
Produces antibodies specific to a certain antigen
What is the role of macrophages?
Phagocytosios of foreign cells and antigen presentation
What antibody is found in non-blood fluids?
IgA
What is the treatment of anaphylaxis?
IM adrenaline
How is the classical complement pathway activated?
IgM and IgG creating a complex with the antigen
What is the role of neutrophils?
Phagocytosis
- Their death causes pus
What is the role of eosinophils?
Combat parasitic infection via release of toxins and degranulation
- Drives inflammation via release of cytokines
What does MHC I present to?
CD8 cells
What does MHC II present to?
CD4 cells
Describe type I hypersensitivity
IgE mediated release of histamine from a mast cell
Describe type II hypersensitivity
Mediated by IgM and IgG binding to antigens on body cells
- Common cause of autoimmune conditions
Describe type III hypersensitivity
Mediated by complexes of IgM and IgG with antigen
- Cause of drug reactions
Describe type IV hypersensitivity
Cell mediated by T cells
- delayed reaction
What is the clinical presentation of Rheumatoid arthritis?
Chronic inflammatory condition - Swollen painful joints - Skin inflammation - Pericarditis _ Pulmonary nodules
What is the mechanism of action of Inflixumab?
Mono-clonal antibody of TNF-a
- Prevents TNF-a from binding to its receptor
What conditions can be treated by influximab?
RA, ulcerative Crohns, psoriasis
