t cell activation Flashcards
what are the requirements for t cell activation?
Antigen presented as peptides
by APCs using MHC molecules
Co-stimulators on the APCs
Cytokines
what are co- stimulators
APCs express molecules that are required for t cell activation in addition to the antigen
what are co stimulators (2)
Co-stimulators are important molecules that help activate our immune system
what happens when you have an activated APC
increased expression of co stimulators and secretion of cytokines
what are b7 co stimulautors?
molecules found on immune cells that play a crucial role in activating T cells.
what do t helpers do?
T helper cells
co-ordinate the immune response
what does a non specifc defense lead to?
macrophage/ neutrophil activation/ leukocyte migration
what does humoral immunity lead to?
activation of B cells
what does cellular immunity lead to?
activation of t cytoxic cells
what is the role of naiive t cells
Naïve T cells differentiate into different types of T helper cells
what is naive t cells dependant on?
is dependent on the type of cytokine secreted by the APC also dependant on what other cells are there as well
what does Pro-inflammatory macrophages give rise to?
Tissue damage
what does Anti-inflammatory macrophages give rise to?
Tissue repair
what does the TREG cell do? 1/2
Immunosuppression by binding to B7 molecules on APCs
what does the TREG cell do? 2/2
inhibit activation of neutrophils
- promotes angiogenesis
summarise Cytotoxic T cell activation
APCs are usually dendritic cells
Antigens need to be presented on MHC I molecules
T helper cells aid in CTLs activation in 2 ways