Unformatted text preview: lymphocytes which bind to and destroy host cells that are infected by bacteria or viruses, or otherwise damaged (i.e., cancerous cell). (See Figure 5) Figure 5 Helper T-cells are essential in an efficient immune response. When activated by an APC , they secrete stimulatory chemicals that stimulate innate immunity, B-lymphocytes and other T-lymphocytes. These are the cells that are destroyed in HIV infection. (See Figure 6) Figure 6 A minority of T-lymphocytes will differentiate into memory T-lymphocytes which circulate in the blood for weeks, months, years, or decades. These cells respond aggressively and quickly to exposure to the antigen that stimulated the initial immune system response. The presence of memory cells explains the long duration of acquired immunity after exposure to an antigen....
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- Fall '10
- Anatomy, host cells, unique T-cell receptors, T-lymphocytes, Tlymphocytes