Plasma cells are a kind of immune cells, and the immune cells in the human body mainly refer to white blood cells, especially lymphocytes, which are further divided into two major categories, namely, T-lymphocytes and B-lymphocytes. When bacteria, fungi, mycoplasma and other microorganisms invade the human body through broken wounds, the immune cells in the human blood will quickly recognize these invaders, and at the same time activate the immune function of the cells, using various ways to remove these invaders, preventing the organism from being infected, in which the B-lymphocytes activated to become plasma cells, secrete the appropriate antibodies, and remove the pathogenic microorganisms that cause disease through antibody encapsulation, phagocytosis and other ways. It can be seen that plasma cells are B lymphocytes in the activated state, and their main function is to participate in the humoral immune response to remove pathogenic microorganisms that invade the human body.