Intact Proinsulin, ELISA

Measurements of proinsulin are used in the diagnosis and treatment of patients with
type 2 diabetes
Proinsulin is a precursor molecule for insulin and is synthesized by the pancreatic
β-cells. Under normal circumstances, virtually all proinsulin is cleaved at residues 32-
33 and 65-66 to produce insulin during the formation of secretory granules. Some
unmodified proinsulin is released into the circulation, though it is believed to have
little or no biological activity. Increased concentrations of circulating proinsulin may
occur in insulin-resistant syndromes such as type 2 diabetes and in patients with
insulinoma. When used in conjunction with a highly specific insulin assay, it may provide
useful information on changes in the processing of insulin in such situations.