Antibodies directed against the E region of pro-insulin-like growth factor-II used to evaluate non-islet cell tumor-induced hypoglycemia.

Abstract

Detection of incompletely processed precursor forms of insulin-like growth factor-II ("big" IGF-II) in plasma is essential for both the diagnosis and follow-up of non-islet cell tumor-induced hypoglycemia (NICTH) and may be relevant to other diseases as well. RIA using an antibody raised against a synthetic peptide consisting of the first 21 amino acids of the E domain [E(68-88)] of human pro-IGF-II cannot distinguish between E-peptide-containing big IGF-II and cleaved E domain or fragments. We therefore developed and validated an ELISA that specifically detects big IGF-II in plasma.