Immunodiffusion Techniques in Clinical Medicine

A variety of abnormalities in serum protein may be seen in patients afflicted with different diseases. Most of these changes are nonspecific and serve only as indicators of the existence of a pathologic state. Changes may be due to the presence of an anomalous protein in the serum or a significant variation in the concentration of a normal component. Because of the high resolution and specificity, immunodiffusion techniques serve as ideal analytical tools for studies of serum-protein changes. Thesingle diffusiontechnique was developed by Oudin in 1946. He showed that when antigen was layered over an agar antiserum mixture in a tube, the precipitin band formed is directly related to the concentration and the diffusion coefficient of the antigen, and inversely proportional to the concentration of the antibody. Following these observations,double diffusiontechniques were developed independently by Ouchterlony and Elek. Here the antigen and the antibody are allowed