Figure 2. The Elution Profile of 125I-labeled Insulin antibody Complex by Molecular Sieve High-performance Liquid Chromatography. Insulin Autoimmune Syndrome compared to Essential Monoclonal Gammopathy
The ordinate shows counts per minute (cpm) and ultraviolet absorbance at 280 nM. (A) The patient with insulin autoimmune syndrome (see Figure 1A) had a more heterogeneous elution profile with the main peak accounting for 68.2% of the total radioactive counts. (B) The 64-year-old man with monoclonal gammopathy had a more uniform elution profile. Additional studies indicated the molecular size (Mr) of the IgG insulin complex was 170,000. The IgG was 160,000 and insulin 5,700. Because the IgG had two insulin binding sites the complex was calculated to have a molecular size of 171,400, very similar to the 170,000 identified. (From Diabetes Care5 and reprinted with permission of the American Diabetes Association. Copyright 1989.)