Immune System Flashcards
What are the two major immune responses?
- Cell-mediated response (T-lymphocyte driven)
- Humoral response (B-lymphocyte driven)
Where do B and T lymphocytes originate from?
Both originate from bone marrow, T-lymphocytes mature in the thymus gland with macrophage assistance.
How do B-lymphocytes act?
They secrete antibodies (aka immunoglobulins), which can specifically attack an antigen.
What are six ways that antibodies and other complement proteins can attack antigen bearing particles?
- Lysis (digesting plasma membrane)
- Opsonization (make plasma membrane susceptible to phagocytosis)
- Agglutination (clumping of antigen bearing cells)
- Chemotaxis (attracting other cells (ie. phagocytes) to the area
- Inflammation (migration of cells, release of fluids and dilation of blood vessels)
What is an activated antibody secreting B-lymphocyte called?
Plasma cells
True or false? Both T and B lymphocytes produce memory cells
true!!
What are the lymphatic organs?
- Lymph nodes
- Thymus
- Spleen
In addition to being the place where T-lymphocytes mature, what does the thymus do to promote T-lymphocyte activity?
Secretes thymosin
What are two general functions of lymph nodes?
- Non-specific filtration of bacteria and other particles from the lymph using the phagocytic activity of macrophages
- The storage and proliferation of T-cells, B-cells and antibody production
What do the two components of the spleen do?
White pulp
- Filter damaged RBCs
- Filter cellular debris
- Filter foreign particles from the blood
Red Pulp
- Store erythrocytes
Superantigens bind with 20% of T lymphocytes that they are presented to. Conventional antigens bind with about 1 in 100,000 T cells.
Superantigens increase the number of activated T cells over conventional activation levels by a factor of ___?
20,000
Taking 20% of 100,000 yields 20,000
