Immunology Flashcards
IL associated with pyrexia
IL-1
IL-6
IL associated with neutrophil chemotaxis
IL-8
IL associated with B cell differentiation
IL-6
Site of action of IL-1
Action
Macrophages
Fever
Site of action of IL- 8
Action
Macrophages
Neutrophil chemotaxis
Site of action of IL-6
Action
Macrophages
Fever
B-cell differentiation
Mastocytosis
- What is it?
- What are the symptoms?
= proliferation of mast cells, neoplasm
Symptoms of carcinoid + urticaria
Marker in hereditary angioedema
Deficiency
C4 (because we have been there BEFORE)
Deficient = C1
C1 = vascular permeability > leaky vessels
CD4 T cells
- Express
- Also known as
MHC Class II
T helper cells
CD8 T cells
- Express
- Also known as
MHC Class I
Cytotoxic T cells
Further subdivision of CD4 cells
- How can they be told apart?
Th1 and Th2 cells
Classification depends on cytokines released
Th2 = humoral immunity (cytokines focus on Ab release)
Th1 = cell mediated immunity (cytokines focus on killing T cells)
How does IL-1 mediate the sepsis response?
Activates platelet activating factor, prostaglandin and nitric oxide
= potent vasodilators
Action of IL-5
Production and activation of eosinophilsA
Action of G-CSF
Allows development and activation of neutrophils
Action of TNF-alpha
Fever
Macrophage activation
Action of INF-gamma
Activation of macrophages
Cytokines which result in fever (3)
IL-1
IL-6
TNF-alpha
Action of INF-alpha
Activates macrophages
What activates the classical complement pathway?
IgM antibodies
IgG antibodies
What activates the alternative complement pathyway?
IgA
Endotoxin - LPS released from lysis of bacterial cell wall
Complement deficiency associated with immune complex disease
- Examples (3)
C2 and C4
- SLE, HSP, glomerulonephritis
Complement deficiency in recurrent infections
C5-C9
Alternative pathway
C3
Classical pathway
C1 > C4 > C2 > C3 > C5-9
Which antibody is the most abundant?
IgG
Can IgG cross the placenta?
Yes - hence issue with anti-D IgG antibodies in future pregnancy
Monomer antibodies (2)
IgG
IgD
Pentamer antibody
IgM
Which antibody activates the alternative complement pathway?
IgA
Autoimmune haemolytic anaemia
- Cold
- Warm
Cold = IgM because cold is Miserable: intravascular
Warm = IgG
Cryoglobulinaemia
Type 1
Type 2
Type 3
Type 1 = monoclonal
Type 2 = mixed monoclonal, polyclonal
Type 3 = polyclonal
Association with Type 1 cryoglobulinaemia (2)
Myeloma, Waldenstroms
- one clonal cell proliferating
Association with Type 2 cryoglobulinaemia (2)
Hepatitis C, Lymphoma
Type II hypersensitivity
- problem
- example (5)
Cell bound = antibody binds to cell surface
e.g. autoimmune haemolytic anaemia, transfusion reaction, post-streptococcal glomerulonephritis, goodpastures, ITP
What type of hypersensitivity is Grave’s disease?
Type II - TSH antibody binds to receptor, causing thyroid effects
Type III hypersensitivity
- problem
- example (4)
Immune complex = antibodies, free antigen and complement bind together to form complexes
e.g. drug induced haemolytic anaemia, hypersensitivity pneumonia, malaria, SLE
Direct Coomb’s Test
- aim of test
- example
Aim = looking for antibodies bound to red blood cells
- AIHA - will be positive
Indirect Coomb’s Test
- aim of test
- application
Looking for free antibodies in serum
e.g. prior to transfusion, pregnancy for anti-D/other sensitising antibodies
What mediates hyperacute organ rejection?
B cell mediated - antibodies attack and destroy graft
- Present due to previous sensitisation event
What mediates acute organ refection?
T cell mediated - T cells migrate out of graft, processed then invade
Pathogenesis of graft vs host disease
Donor lymphocytes attack antigen of recipient
B cell only disorders (4)
IgA deficiency
Common variable immunodeficiency
Bruton’s
Hypogammaglobulinaemia
Infection pattern in B cell disorders
Pyogenic bacteria
Yeasts
Giardia
Bruton’s immunodeficiency
- genetics
- presentation age
- problem
X-linked inheritance
Under 6 months at presentation
No B cells present
Combined B cell and T cell deficiencies (3)
Severe combined immunodeficiency
Ataxic Telangiectasia
Wiskott-Aldrich
Ataxic Telangiectasia
- genetics
- presentation (4)
Autosomal recessive
Cerebellar ataxia, occular telangiectasia
ENT, chest infections
Wiskott-Aldrich Syndrome
- genetics
- infection
X-linked recessive
Pyogenic infections
Infection pattern in T cell disorders
Opportunistic infections
T cell disorder (1)
DiGeorge Syndrome
DiGeorge syndrome
- genetic mutation
- pathogenesis
- presentation (3)
22q11 deletion - part of long arm Ch 22 is missing
- Absence of a thymus due to issue with 3rd/4th pharyngeal pouch
Hypoparathyroidism, CV problems, opportunistic infections
Infection pattern in neutrophil disorders
Gram -VE bacteria
Staph aureus
Viral infections
Aspergillus
Chronic Granulomatous Disease
- genetics
- pathogenesis
- when presents?
X-linked
Defect in NADPH oxidase axis
Presents in first 2 years of life
What kind of hypersensitivity reaction is ITP?
Type II - antibodies bind to platelets
Function of IgD antibodies
Activate B cells
Hyperacute transplant rejection mediated by which antibody?
IgG
