Question

Differentiate immunogen from antigen. Explain the natural and potential antigens.

Answer 1

Immunogen is the term which is used to describe a molecule that can generate an immune response and hence, is called an immunogen.

The molecule which can react with the antibody which is produced, or with the activated cellular constituents of cell-mediated immunity is referred to as an antigen.

Antigens may be natural or artificial ones. Natural antigens are of two types, particulate and soluble antigens. Bacteria, viruses erythrocytes and cells represent particulate type antigens. Bacterial toxins, proteins, carbohydrates, glycoproteins and lipoproteins represent the soluble antigens.

Chemical compounds, biological macromolecules, synthetic polypeptides are regarded as potential antigens.Several polysaccharides, nucleoproteins and lipoproteins are also considered as antigens.