Immunology Flashcards
In X linked SCID which receptor is damaged? What does this mean?
IL2. This means that there is an inability to respond to cytokines leading to failure of T cell and NK cell development.
What is the purpose of lymph nodes?
clearing zones where a foreign material presented by dendritic cells can result in rapid generation of lymphocytes highly selective for the microbe bearing that material.
In SCID is it T cells or B cells that are reduced?
T cells
Describe how a granuloma is formed
Infection with mycoabacteria
Infected macrophages stimulated to produce IL12
IL12 induces T cells to secrete gIFN
gIFN feedsbackk to macrophages and neutrophils and stimulated production of TNF
What is a granuloma?
An organised collected of activated macrophages and lymphocytes
What is deficient in common variable immune deficiency?
IgG IgA IgM
How does variable immune deficiency usually present?
Recurrent bacterial infections such as respiratory
How does selective IgA deficiency present?
Asymptomatic
Recurrent respiratory tract infections
In what way is HIV similar to SCID?
Absence of functional T cell immunity
What is a type 1 hypersensitivity reaction?
Immediate hypersensitivity (IgE-mediated allergy)
What is a type 2 hypersensitivity reaction?
Direct cell killing: antibody mediated
- Activation of complement leading to cell lysis
= Opsonisation leading to antibody-mediated phagocytosis
Give examples of type 2 hypersensitivity reactions
Autoimmune haemolytic anaeamia
Idiopathic thrombocytopaenic purpura
Do biologics such as anti TNF represent passive or active immunity
: Biologicals such as anti-TNF (e.g. Etanercept, Adalimumab) represent a form of passive immunisation.
IF you are on anti TNF treatment what infections are you particularly at risk of?
Granulomatous
What is a type 3 hypersensitivity reaction?
Immune complex mediated (eg SLE)
