The lymphatic system is a network of delicate tubes throughout the body. It drains fluid (called lymph) that has leaked from the blood vessels into the tissues and empties it back into the bloodstream via the lymph nodes.
 

The main roles of the lymphatic system include:

• managing the fluid levels in the body

• reacting to bacteria

• dealing with cancer cells 

• dealing with cell products that otherwise would result in disease or disorders

• absorbing some of the fats in our diet from the intestine.
   

The lymph nodes and other lymphatic structures like the spleen and thymus hold special white blood cells called lymphocytes. These can rapidly multiply and release antibodies in response to bacteria, viruses, and a range of other stimuli from dead or dying cells and abnormally behaving cells such as cancer cells.