1 Most of these diseases are infections, caused by a variety of bacteria, viruses, and parasites that can be foodborne. 2  Other diseases are poisonings, caused by harmful toxins or chemicals that have contaminated the food, for example, poisonous mushrooms.
(cluster designation 4) symbol for a glycoprotein expressed on the surface of helper T lymphocytes and other immune cells. CD4 serves as a receptor for human immunodeficiency virus envelope glycoprotein gp120.
1 The HIV enzyme protease, which is produced by the cell's biochemical machinery from the viral DNA incorporated into the cell's chromosomes, catalyzes the cutting of these proteins to their proper size. 2  New HIV particles (viruses) are assembled inside the cell from the cut viral proteins and the viral RNA copies.he immune system is a collection of cells found in the blood and in tissues throughout the body that help to protect the body from infection. These cells perform a variety of nonspecific and specific functions to defend the body against harmful particles (e.g. , bacteria, viruses, toxins, and cancerous cells).