Host defence - PreRec Flashcards
Define adaptive immunity
An antigen-specific immune response
B cell function?
Produce antibodies
What are the 3 T cell types?
1) Cytotoxic
2) Helper
3) Memory
Cytotoxic T cell function?
Track down infected cells
Helper T cell function?
Secrete cytokines to attract macrophages and neutrophils
What are the 5 properties of the adaptive immune response?
1) Diversity
2) Specificity
3) Effector Functions
4) Self Tolerance
5) Immunological Memory
What is VDJ recombination?
Each type of segment added together to make variable region, generates large diversity with high mutation rate
What is an MHC molecule?
Series of cell surface proteins on immune/non-immune cells needed for T cell recognition
Which antibody is the most abundant type? (And special function?)
IgG, able to cross the placenta to protect the neonate
Define immune tolerance
State of unresponsiveness of adaptive immune system to antigens
Where does central and peripheral tolerance occur?
1) Central: BM and Thymus, (Autoreactive clones deleted, supp reg TC generated)
2) Peripheral: Lymph Nodes (AR clones Escape tolerance, suppressed by Treg/inhibitory)
What are 5 consequences of failing immune system?
1) Failure of T cell function leads to infection
2) Fail tolerance –> AI disease
3) Overactive adap immunity –> Tissue damage
4) Failure of AB production –>Bacterial infections
5) Fail to eliminate pathogens –> Chronic inflammation
What causes inflammation to be chronic?
1) Initiating cause persists
2) Cellular response inappropriate
3) Structural abnormalities
What are the 3 patterns of chronic inflammation?
1) Chronic suppurative
2) Chronic autoimmune
3) Chronic granulomatous
