Specific Cellular Barrier - Adaptive Immunity/3LoD Flashcards
What is the Major Histocompatibility Complex and what are 3 key features of it?
MHC = region on DNA that codes for 3 classes of MHC proteins.
- MHC is inherited
- MHC has the highest rate of mutation (increases likelihood to bind to an antigen)
- MHC binds to processed antigenic peptides
Which MHC class is described?
1. present on surface of all nucleated cells
2. is membrane-bound
3. present endogenous antigens to/bind to CD8+ receptors of cytotoxic T cells
Class I
Which MHC class is described?
1. present on APCs (macrophages, dendritic cells, B cells)
2. present exogenous antigens to/bind to CD4+ receptors of helper T cells
Class II
Which T-cell surface marker is associated with signal transduction?
CD3
What region of the alpha and beta chains of T-cell antigen receptors is where an antigen binds?
Variable region
Where are the majority of T cells eliminated (negative selection)?
In the developing stage/as thymocytes in the thymus (immature lymphocytes)
Where are the non-eliminated T cells (positive selection)?
T cells (mature lymphocytes) are in the secondary lymphoid organs (as CD4+CD8- or CD4-CD8 T cells) such as the spleen or lymph nodes
Where in the thymus are immature T cells vs. mature T cells?
Cortex (immature)
Medulla (mature)
Participation in delayed-type hypersensitivity, and secretion of IFN-gamma cytokines describes which helper T cell?
Th-1
Helping other cells (B or Tc) by secreting IL-4 describes which helper T cell?
Th-2
Regulation of the inflammatory response and secretion of IL-17 describes which helper T cell?
Th-17
What is the function of the cytotoxic T cell “Treg”?
regulation of the immune response via suppression and secretion of TGF-beta cytokine
