T cell mediated immunity Flashcards
Covers Janeway 7th ed pp 323-325
Mature circulating T cells that have not yet encountered their specific antigens are known as:
Naive T cells
A naive T cell that meets its specific antigen, presented to it as a peptide:MHC complex on the surface of an APC, is induced to:
proliferate and differentiate into effector T cells
All effector T cells act on other …. cells, because they require antigens to be presented on …
Host, MHC
CD8 T cells recognise pathogen presented on
MHC class 1 molecules
Naive CD8 T cells differentiate into ……… T cells that recognise and kill ………. cells
cytotoxic, infected
CD4 T cells recognise pathogen presented on … ….. .
MHC class II
The main CD4 effector subsets are:
Th1, Th2, Th17
The primary function in the adaptive immune response of Th17 CD4 effector T cells is:
To enhance neutrophil response
The two main functions of Th1 CD4 effector T cells in the adaptive immune response is:
- To activate infected macrophages
2. Assist B cells with antibody production
The two main functions of Th2 CD4 effector T cells in the adaptive immune response is:
- Assist B cells with antibody production
2. Assist B cells with switching to IgE
The main function of CD8 cytotoxic T cells is:
To kill virus infected cells
The pathogens targeted by CD8 cytotoxic T cells are:
- Viruses
2. Some intracellular bacteria
The pathogens targeted by CD4 Th1 cells are:
- Microbes that persist in macrophage vesicles (e.g. mycobacteria, Listeria, Leishmania, pneumocystis)
- Extracellular bacteria
The pathogens targeted by CD4 Th2 cells are:
Helminths
The pathogens targeted by CD4 Th17 cells are:
Extracellular bacteria
The general role of CD4 regulatory T cells (various types) is to:
Suppress T cell responses
The activation of naive T cells in response to antigen, and their subsequent proliferation and differentiation into effector cells, constitutes a ……. ….-…….. …… ………
primary cell-mediated immune response
The two major components of cell mediated immunity stimulated by effector T cells are:
- Macrophage activation
- Cytotoxicity
(also stimulate B cell antibody production - non cell mediated immunity)
What type of T cell is generated in addition to effector T cells as part of the primary T cell response?
Memory T cells
The activation and clonal expansion of a naive T cell is often called: ……. . Why?
Priming; to distinguish it from the responses of effector T cells to antigen on their target cells and the responses of primed memory Tcells
In the activation of naive T cells, signal 1 is:
Antigen specific activation of the T cell receptor
In the activation of naive T cells, signal 2 is:
Interaction of costimulatory molecules on APCs with ligands on the T cells
In the activation of naive T cells, signal 3 is:
Cytokines that control differentiation into different types of effector cells
What sets in motion the 3 signals for activation of naive T cells?
Much earlier signals arising from the intial detection of the pathogens by the innate immune system
Give an example of a receptor of the innate immune system
TLRs
What pattern do TLR and other similar receptors recognise? Why is this essential?
They recognise pathogen associated molecular patterns that signify the presence of non-self. These signals are essential to activate APCs so that they can activate naive T cells
What is the most important APC?
The dendritic cell
What is the function of a dendritic cell?
To ingest and present antigen
Are DCs part of the innate or adaptive immune response?
DCs detect antigen at sites of infection and are activated as part of the innate immune response
When a DC is activated, what does it do?
Activated DCs migrate to local lymphoid tissue and mature into cells that are effective APCs for recirculating naive T cells.
