APC and Antigens Flashcards
Where would you be most likely to find DCs?
- lymph nodes, skin and mucosa where invaders are
BCR on the surface that can recognize soluble antigen
- B-lymphocytes
Needs to be acquired and presented to CD4+ helper T- lymphocytes by professional APCs
- exogenous antigens
Peptide generated in endosome and or phagosome by lysosomal proteases
- MHC-II antigen processing
Antigen presenting cells only. Present phagocytosed antigens to T-helper (CD4+) cells. Extremely important for mature B cell responses (antibodies)
- MHC class 2
Peptide transported by TAP
- MHC-I antigen processing
Antigen presenting is their only job. 100x more efficient at MHC-II presentation.
- Dendritic cells
Infected nucleated cells process and present endogenous antigen via MHC-I molecules to Cytotoxic T lymphocytes (CD8+ T cell)
- Cell-mediated immune response
Bind antigen with the BCR and then ingest and process the antigen before presenting it via MHC-II (peptide ONLY) molecules to T- helper cells.
- B lymphocytes as APCs
Bind antigen with the BCR which then sends a signal to the B-cell to differentiate into an antibody secreting cell
called a plasma cell. B-cell takes up, processes and presents antigen to a T-helper cell (CD4+)
- B cells as antibody-producing cells
Present exogenous antigens to CD4+ T-lymphocytes (T-helper lymphocytes)
- MHC-2 antigen presentation
Peptide generated in cytoplasm by proteosome
- MHC-I antigen processing
APC process and present exogenous antigen via MHC-II molecules to T helper lymphocytes (CD4+ T cell). T-helper cells can help B cells to make antibody
- humoral immune response
Most T-lymphocytes only recognize antigen when bound to ?
- MHC molecules (MHC restriction)
Main role is antibody production. Has a B cell receptor (BCR)- membrane bound antibody. BCR is not restricted to protein antigens and can directly bind antigen
- B cells
Surface membrane proteins that display both self and non-self antigens for recognition by T lymphocytes
- Major Histocompatibility Complex (MHC) Molecules
Must be activated before antigen exposure to present. Can only present to previously sensitized T-helper cells. The Primary APC of the brain and testis
- Macrophages
Surface membrane proteins that display both self and non-self antigens for recognition by T lymphocytes (CD4 and CD8)
- Major Histocompatibility Complex (MHC) Molecules
The only APC that can present and activate T cells that have never encountered antigen before (naïve T-cells). Thus, they are essential for initiating the primary immune response. Produced from bone marrow stem cells.
- dendritic cells
All nucleated cells. Present cytoplasmic antigens to cytotoxic T-cells (CD8+). Important for killing virally infected cells.
- MHC class I
TCR on the surface that can recognize linear peptide antigen only in the context of MHC
- T-lymphocytes
Present endogenous antigens to CD8+ T- lymphocytes (cytotoxic T-lymphocytes, killer T lymphocytes)
- MHC-I antigen presentation
Express on MHC-II and present exogenous antigens
- Antigen presenting Cells
1. Dendritic Cells
2. Macrophages
3. B-cells
