Major Histocompatibility Complex And T-Cell Receptor Flashcards
Describe HLA/MHC Class I and II in terms of…
- The chromosome that codes for them
- Their major loci
- What tissues they are found on
- Which T-cells recognize each class
Class I:
- Chromosome: Short arm of chromosome 6
- Major Loci: A, B, C
- Tissues: all nucleated cells
- T-cells: Cytotoxic T-cells (CD-8)
Class II:
- Chromosome: Short arm of chromosome 6
- Major Loci: DP, DQ, DR
- Tissues: B-Cells, Antigen-Presenting Cells, Macrophages
- T-Cells: T-helper Cells (CD-4)
Recognize the MHC Class I and II domains responsible for binding antigen and the types of antigens presented
Class I:
- Viruses, Intracellular Bacteria, Mutations
- Peptide binding domain: alpha 1/alpha 2 (long alpha chain, short beta 2-microglobulin)
- Endogenous Antigens (not phagocytized)
Class II:
- Bacteria
- Peptide binding domain: alpha 1/beta 1 (long alpha and beta chain)
- Exogenous Antigens (phagocytized material)
Recognize the structure of the T-cell receptor (TCR) and explain the function of the CD3 complex
- Heterodimer with one alpha chain and one beta chain
- Top region is variable and binds antigen (epitope) presented by MHC-I or by MHC-II
CD3 Complex: required for TCR development and function; important in signal transduction after activation
Know which type of lymphocytes express CD4, CD8, and CD28
CD-4: MHC Class II
CD-8: MHC Class I
CD-28: co-stimulatory molecules with ligands (T-Cells)
Explain the function of TCR accessory molecules
Stabilize the TCR/CD3:MHC complex
Differentiate the roles of TH1 and TH2 lymphocytes
TH1: promote CELL-mediated responses
- Drive differentiation of cytotoxic T cells and natural killer cells
TH2: promote ANTIBODY-mediated responses
- Drive B cell activation and differentiation
Which (if any) of the following cells lack MHC-1?
- Neutrophils
- Lymphocytes
- Red Blood Cells
Red Blood Cells
