Time-Resolved Fluorescence Assays for Quantification of Insulin Precursors in Plasma and Serum

: In metabolic diseases such as obesity and type 2 diabetes mellitus, the conversion of proinsulin to mature insulin can be impaired. This could mean that insulin molecules with lower activity toward the insulin receptor can be released under conditions of high metabolic demand, resulting in an inadequate glucoregulatory response. The chapter describes a fluorescent monoclonal antibody-based protocol for measurement of human proinsulin and the proinsulin conversion intermediates (split proinsulins). An example assay is presented using serum from non-diabetic, normal body mass index individuals.