Antibodies are a protein which are produced by white blood cells, more specifically B-Cells or B-lymphocytes. They’re produced when the body is invaded or infected by a pathogen which have a certain unique sets of molecules on their surface called antigens.

When the B-Cells come into contact with a foreign antigen, so one that has not been in the body previously, they will start creating antibodies to lock onto the pathogen. This is so that other white blood cells may find them and engulf them. These type of blood cells are in a group which are called macrophages or phagocytes. This process is called phagocytosis. These type of cells are called the T-Cells and when they do kill the invasive pathogen they also save a part of its DNA so if it’s to return, the body would be able to produce many more antibodies to kill the pathogen much more quickly. It’s also worth mentioning that the antibodies created by the B-Cells are specific to that pathogen. This means that after the pathogen has been in the body twice and provided the body defeats it, one is then has natural immunity. This is different from acquired immunity where you have to insert an inactive strand of pathogen into the body for the T-Cells to engulf and remember them.

White blood cells can also be called leukocytes and these are distinguishable from red blood cells due to the fact that they have a nucleus, whilst red blood cells do not.