autoimmunity Flashcards
What was the origion of the adaptive immune system
500 million years ago in vertibrates
invertibrates do not have
jawless vertibrates
What is an immune difficeny
how is it caused
Immune difficency is a lack of response by the immune system which can be inherited or virally induced
What is a genetic and virally dirrived immune difficeny disorders
Survere combined immunodeficiency
- X linked genetic disorder
- Removes functional B cells and T cells
- impacts males more than females
HIV
- Virus which targets CD4 T-cells
- bind to the CD4 receptor
- loss of CD4 helper t cells leads to lack of CTL and B cells
- impacts immunity to other microbes and cancers
What is autoimmunity
When your body creates an immune response againt self antigen
main reponse from adaptive system
What normally prevents autoimmunity
Self tollerance developed in the thymus for T-cells and the bone marrow for B-cells. they remove self reactive lymphocytes
What are two examples of auto immune diseases
Rheumatoid arthritis:
- targets the joints
- more common in old people
- impacts 1% of poeple due to autoreative T and B cells
- leads to remodeling of the joint and tissue damage
type 1 diabetes:
- CTL attack the Beta islets of the pancrease
- leads to no insulin production
What is an allergy and alergen
An alergen is an antigen which produces allergy reponse
allergens are normally acepted foriegn antigen
triggers can be chemical and lead to effects from hay fever to anaphlaxis
Describe the order of events for a general alergic reponse
Phagocytes phagocytose allergen which is then presented on MHC-2
MHC-2 is red by CD4 helper cell sends cytokines to B-cells which differentiate to plasma cells
Plasma cells then secreate IgE which binds to Fc receptors on mast cells with the Fc domain
When these Fc receptors encounter antigen then mast cell degranulate releasing histomines + inflamitory mediators causing a large immune reponse
What is class switching
An event which can happen late in the primary immune reponse or in the secondary immune reponse
Section of the heavy chain swaps to become a new IG, variable/antigen recognising region remains constant throughout this process
How long are detected peptides
9 amino acids
