L7 - Adaptive Immunity (T Cells)

Do T-cells recognise free antigen in its native conformation?

No, antigen needs to be processed by a APC to be recognised

Steps of T cell development

• Hematopoietic stem cells in BM go to thymus

• T cells undergo thymic education

• Mature naive T cells move to peripheral lymphoid tissues

• T cell are activated, turning into effector T cells to mount immune response

What gene segments encode the TCR-alpha genes?

V, J, C gene segments

What gene segments encode the TCR-beta genes?

V, D, J, C gene segments

Proteolysis

Process where proteins break down, which is required to create epitopes for TCRs to recognise antigens

What chromosome is MHC genes found on in humans?

Chromosome 6

What type of T cell binds to MHC-II?

CD4+

TAP

Transporter associated with antigen processing

What does dendritic cell activation result in?

• Increased expression of MHC markers

• Expression of co-stimulatory molecules (CD80, CD86)

• Secretion of cytokines

• Migration of DC from the tissue to secondary lymphoid organs

Role of APCs

• Take up antigens and display peptides of MHC

• Activate T-cells

• Signalling by PRRs following ligation with PAMPs

MHC-II presents peptides largely derived from…

exogenous proteins

MHC-I presents peptides largely derived from…

endogenous proteisn