Introduction to Immunology and Pathology Flashcards
What makes up the innate immune system?
- physical epithelial barriers
- Macrophages/monocytes
- dendritic cells
- Natural Killer cells
- circulating plasma proteins
Why can Macrophages recognize bacteria?
-bacteria are made up of fats and carbs non normally found in the human body
What is a phagolysosome?
-vesicle inside a macrophage that contains an ingested bacterium and a lysosome
Why does a bacterial infection lead to a red swollen area?
- macrophages ingest bacteria and release cytokines that increase blood flow to area
- also allows for endothelial cell contraction, allowing more white cells and fluid to escape to the ECF
Which region of the antibody binds onto antigens?
-Fab (light chains)
What is the most common circulating antibody in the blood?
IgG
What happens once a B cell matches a cognate antigen?
- it is triggered to divide
- after a week of dividing there are 20,000 identical copies
- then they all make and secrete antibodies
What is opsonization?
- when antibodies bind to and tag invaders for destruction
- Complement binding is also involved
How doe antibodies fight viruses?
- bind to viruses that are outside of cells
- prevent them from entering cells
- virus then opsonized and phagocytized
What are the three types of T cells?
- Cytotoxic T Lymphocytes (CTLs)
- Helper T cells (Th)
- Regulatory T Cells (Treg)
What proteins present antigens to T cells?
-Major Histocompatiblilty complex (MHCs)
Where are Class I MHCs found?
- found in varying amounts on most cells in the body
- inform killer T cells what’s going on inside the cell
Where are Class II MHCs found?
-only on Antigen Presenting Cells (eg Macrophages)
Which class of MHC can present larger protein fragments?
-Class II
Where is the adaptive immune system activated?
- lymph nodes
- spleen
