In simple terms, a monoclonal antibody is derived from a single cell line made by using one type of an immune cell that is a clone of a unique parent cell. It is produced by injecting a specific antigen into a mammal (mouse) to create a monoclonal antibody that binds specifically to the epitope on that antigen. In most cases, they are produced in mice, but other species have been used. Monoclonal antibodies are purer and have a higher affinity and selectivity than polyclonal antibodies. Monoclonal antibodies are homogeneous and free of non-specific antibodies, which are some advantages to using them.