Polyclonals can be used for Western blot, immunohistochemistry on frozen slices or parrafin fixed tissues. The advantage is that there are more epitopes available in a polyclonal antiserum to detect the proteins than in monoclonal sera.Rabbits are used for polyclonal antibody production by BT-Laboratory. Rabbit antibodies are very stable and can be stored for several days at room temperature. BT-Laboratory adds sodium azide and glycerol to enhance the stability of the rabbit polyclonal antibodies. Anti-human, anti mouse antibodies to highly immunogenic selected peptide sequences are" monoclonal like" since the epitope to which they are directed is less than 35 amino acids long.