专业术语—口腔生理学术语L2(英文详解)（在线收听）

    Lymphocytes - white cells involved in the immune response. B lymphocytes are so called because they mature in bone while T lymphocytes mature in the thymus. Both cells look alike until they recognise a foreign antigen. The B cell starts to make antibodies while the T lymphocytes accumulate vesicles loaded with cytotoxic agents. On contact with a foreign cell, the lymphocytes changes shape so that all it vesicles are pointed at the enemy. The release of cytotoxic agents need to be carefully controlled. One of the methods by which the enemy cell is killed is by agents which make holes in its cell membrane. Enemy cells maybe bacteria, or the bodies own cells which have ingested viruses or they may be cancer cells, or the cells of transplanted organs.

    Lymphokines - a variety of cytokines released by lymphocytes which coordinate the proliferation of T and B lymphocytes. They also regulate the brain's contribution to the immune response via the hypothalamus - adrenal cortex axis.

    Lysosomes - small membrane bound vesicles in the cy lasm of cells which contain toxic enzymes. When a cell dies, these membranes rupture and the enzymes are released. They break down the cells structure, and the debris is removed. The lysosome also contains cytokines which summon inflammatory cells and stimulate inflammation. The contents of lysosomes can be released by macrophages and neutrophils both to kill bacteria and viruses, and to stimulate inflammation.