Across
- 4. (3 words) Unlike normal endothelial cells lining blood vessels that overlap each other like shingles, the cells making up this structure do not overlap, but rather, are lined next to one another like columns. The space between these columns is just enough space for lymphocytes to wriggle through.
- 6. (1 word) One of the ways of locking in a helper T cell profile is through a ______ feedback loop where cytokines produced by one Th cell subset inhibits the proliferation of other Th cell profiles.
- 8. (3 words) This is demonstrated by injection of the tuberculin protein, where if you’ve previously been infected with tuberculosis, your immune system will have memory Th1 cells that were made in response to the TB, leading to inflammation at the injection site.
- 12. (2 words) A cell type within secondary lymphoid organs. These are not actual white blood cells produced in the bone marrow, but rather, regular somatic cells that take up their final positions in the secondary lymphoid organs as the embryo develops.
- 13. (2 words) A secondary lymphoid follicle that becomes a hub of B cell development after the B cells find their cognate antigens. Looks like it contains a “dark zone” under the microscope due to the density of B cells.
- 14. (2 words) A secondary lymphoid organ that serves to provide an organized and concentrated environment for antigen, APCs, T cells, and B cells to meet and communicate.
- 15. (1 word) One of the ways of locking in a helper T cell profile is through a ______ feedback loop where committed T cells secrete cytokines that encourage the proliferation of that Th cell.
- 16. (2 words) A feature of all secondary lymphoid organs, which can be thought of as islands of follicular dendritic cells within a sea of B cells.
- 17. The helper T cell profile that is best suited for intracellular pathogens such as bacteria and viruses.
- 18. (2 words) An example of MALT in the small intestine. M cells in this tissue transports antigen from the small intestine lumen into underlying tissues.
- 19. (1 word) A “messy” type of cell death where enzymes and chemicals that are normally safely contained within a living cell are released by the dying cell into the surrounding tissues where they cause damage.
- 20. The helper T cell profile that is best suited for parasitic infection in the intestine or bacterial-contaminated food.
Down
- 1. (2 words) Manufactured in cytotoxic T cells. Triggers an enzymatic chain reaction in infected cells that triggers the cell to die by apoptosis.
- 2. (1 word) A close relative of the C9 complement protein. Cytotoxic T cells use this protein to drill holes in the membranes of infected cells.
- 3. The helper T cell profile that is best suited to defend against invaders that do NOT enter cells (ex. fungi and extracellular bacteria).
- 5. (4 words) The region of the spleen where T cells are retained.
- 7. (3 words) Includes the lymph nodes, spleen, and MALT (mucosal-associated lymphoid tissue). Recognition of threats to the immune system takes place in these tissues.
- 9. (3 words) The tissues where lymphocytes are made. Includes the bone marrow and the thymus.
- 10. (2 words) Expressed on the surface of cytotoxic T cells. Binds the Fas protein on the surface of a target cell, triggering the target cell to die by apoptosis.
- 11. (1 word) A secondary lymphoid organ that functions as a blood filter, and screens blood for pathogens.