For a whole slew of terms check out the glossary . The reaction of the immune system to abnormal articles. Antibodies can bind to and, in turn, destroy certain antigens. When you test positive for HIV, they are actually testing for antibodies. A substance which is recognized as foreign by the immune system.
Antigens are either whole microorganisms, or they can be part of an organism or virus.
These are a specific type of leukocytes which are mononuclear. They are a critical part of immune response because they provide the specificity and memory which is needed for long-term immunity. The two main types of lymphocytes are T cells and B cells. Cytokines are chemical substances that are secreted by lymphocytes, monocytes and macrophages. T cells mediate cellular reactions.