Insulin is a peptide hormone produced in the pancreas by the B cells of the islets of Langerhans. Its functional role is to promote glucose utilization, protein synthesis, and the formation and storage of neutral lipids. Lack of this hormone gives rise to diabetes mellitus. Insulin-producing B cells are one of at least seven different cell types within the islets. These pancreatic endocrine cells are present not only within the islets but also in small and variable numbers in extrainsular locations. They can be present either singly or in small clusters along the pancreatic ductular epithelium, as well as within the particular acinar elements. The development of specific antibodies to various polypeptide hormones have made IHC localization of these hormones the most sensitive and reliable means available for an accurate characterization of the function of islet cell tumors. Since many islet cell tumors are multihormonal in nature, classification of the tumor is based on the predominant hormone present. Tumors producing large amounts of insulin are referred to as insulinomas. Insulin producing B cells occupy a central position in the islet, constituting 60% to 80% of the islet cell population. Islet cell hyperplasia and/or multiple adenomas are present in approximately 10% of hyperinsulinism cases. Multiple insulin-producing tumors, hyperplastic islets, areas of nesidioblastosis, and cells budding from the ductular structures stain positive for insulin. This antibody recognizes the A chain loop of human insulin. Cross-reactivity with bovine, rat and mouse insulin has been observed.
|Tissue Type/Cancer Type|
0.5 mL – Manual – Concentrate, 1 mL – Manual – Concentrate, 6 mL – Manual – RTU, 50 Tests – Automation – Xmatrx, 100 Tests – Automation – i6000, 200 Tests – Automation – Xmatrx, 5 slides – Xmatrx, 5 slides – Manual