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.
Human immunodeficiency virus (HIV) infects the cells of the immune system. In particular, HIV attacks and destroys the T helper lymphocytes, or T-cells, which are crucial to the immune system and immune response.These cells are also called CD4-positive lymphocytes because HIV uses the protein CD4, present on the surface of the cell, to attach itself and pry its way into the cell.) Each day, your body produces millions of CD4+ T-cells to help maintain your immunity and fight off invading viruses and germs.