Immunohistochemistry

Immunohistochemistry is a discipline comprising of immunology and histology5.It has gradually developed into a major diagnostic tool in cellular pathology. It is used to identify specific or highly selective cellular epitope (say a particular antigen) which is usually a protein in nature. It also helps to determine the antigenic status of particular cells within a tissue expressing antigens and cellular location of the antigen. Immunohistochemistry (IHC) uses antibodies to distinguish the antigenic differences between cells or say to identify functional differences between cells. It is based on the exquisite specificity of the antibodies for particular antigens7. Since mid 80s it has made significant impact on histological diagnosis due to the use of routinely processed paraffin wax embedded tissues with an antibody and appropriate labeling system5.