Intro to immunology Flashcards
What are the differentiation numbers for T cells? (4)
CD45+
CD3+
CD4+ or CD8+
What do T cells express? (1)
TCR (T-cell receptor)
What are the differentiation numbers for B cells? (2)
CD45+
CD19+
What do B cells express? (1)
BCR (B-cell receptors)
What are the differentiation numbers for macrophages? (3)
CD45+
CD14+
CD11b+
What is an epitope? (1)
The bit of an antigen that a receptor recognises
What does BCR recognise? (1)
Portions of whole proteins
What does TCR recognise? (1)
Short portions of proteins presented to them on MHC
How is receptor diversity created? (2)
Through shuffling genes - produces unique sequences in the TCR or BCR that binds the epitope
What is thymic education and where does it occur? (3)
T cells are ‘tested’ to ensure that they do not recognise self antigens with too high an affinity
Occurs in the thymus
What is central tolerance and where does it occur? (2)
B cells are ‘tested’ to ensure that they do not recognise self antigens with too high an affinity
Occurs in the bone marrow
Where are T cells produced? (1)
Thymus
Where are B cells produced? (1)
Bone marrow
CD45 is expressed by which cells? (1)
By all haematopoetic cells, receptor protein tyrosine phosphatase
CD3 is expressed by which cells? (1)
All T cells
CD19 is expressed by which cells? (1)
All B cells
CD154 is expressed by which cells? (1)
By macrophages
What is clonal deletion? (1)
Developing lymphocytes that are potentially self-reactive are removed before they can mature
What is clonal expansion? (1)
Once a receptor has recognised its antigen it will divide to produce many identical progeny
What are cytokines and what do they do? (3)
Proteins made by cells that affect the behaviour of other cells
Immune cell communication system.
Often dictates the direction of an immune response
What are interleukins? (1)
Cytokines made by lymphocytes
What are chemokines and what do they do? (3)
Small chemoattractant proteins
Stimulate the migration and activation of cells, especially phagocytic cells and lymphocytes
Organise immune cells into discrete compartments in lymphoid follicles
How many types of chemokines are there? (1)
50 types
How can you differentiate between T cells, B cells, and macrophages? (2)
By their differentiation numbers
Express different things on their surface so this allows to differentiate between them (CD number)
How many signals are required to activate an immune response? (2)
At least two signals
Central and proliferate tolerance exists - prevents immune responses towards everything
What is a naive cell? (1)
A cell that has not seen an antigen
What is an activated cell? (1)
A cell that has seen an antigen
What are germinal centres? (3)
Created following an infection
In lymph nodes
Collection of cells that organise themselves in such a way that B cells enter and plasma cells and memory cells leave
What is a transgene? (1)
A mouse strain that is genetically altered by the insertion or deletion of a gene
