That is a $50 price cut for the PS4, which currently retails at $399. A contest hints at a PS4 price drop. In a screenshot we see the PS4 Approximate Retail Value (ARV) listed as $349. This value is typically the retail price of the device that a customer will pay in-store without any discounts.
Diseases of the White Blood Cells. 1  Neutropenia (pronounced: new-truh-PEE-nee-uh) occurs when there aren't enough of a certain type of white blood cell to protect the body against bacterial infections. 2  Human immunodeficiency virus (HIV) attacks certain types of white blood cells (lymphocytes) that work to fight infection.
Immunity. Once inside the body, pathogens reproduce. Viruses reproduce inside cells and damage them, while escaping to infect more cells. Bacteria produce toxins - poisons. Cell damage and toxins cause the symptoms of infectious diseases. Once pathogens enter the body, the immune system destroys them. White blood cells are important components of the immune system.