Effector T Lymphocytes Flashcards
Broadly speaking, how do Cytotoxic T Lymphocytes kill infected cells?
Inducing apoptosis
What are the two mechanisms by which CTLs kill cells?
Granzyme + perforin – perforin makes a pore in the cell membrane through which granzyme can enter and trigger apoptosis
Fas ligand on T cell binds to Fas receptor on infected cell
When Fas has been engaged – it releases CASPASES
Both pathways upregulate CASPASES which drives apoptosis
What are the four main effector functions of CD4+ T Lymphocytes?
Macrophage Activation
B cell Activation
Delayed Type Hypersensitivity
Regulation
What are the two phases involved in Delayed Type Hypersensitivity?
Sensitisation – initial exposure to the antigen
Effector – delayed response
What are the five T helper cell subsets?
Th1 – inflammatory responses
Th2 – boosts anti-multicellular organism responses
Th17 – important in control of bacteria
Follicular T helper cells – essential for generation of isotype-switched antibodies
Treg – regulation of T cell responses
What is the main difference between T cell memory and B cell memory?
T cell memory doesn’t undergo isotype switching or affinity maturation – it does not get better