AffinityImmuno Products

Introduction

GDF15 is a stress-induced hormone that, despite belonging structurally to the TGF-beta superfamily, signals through its own dedicated receptor system: circulating GDF15 binds GFRAL, a receptor expressed on neurons in the brainstem area postrema and nucleus tractus solitarius, which in turn engages the RET co-receptor to trigger downstream ERK signaling. This brainstem circuit converts cellular stress signals – tissue injury, hypoxia, inflammation, oxidative stress, or drug exposure – into an aversive response marked by nausea, reduced appetite, and weight loss. GDF15 is synthesized as a precursor that is proteolytically cleaved into a disulfide-linked mature dimer, and elevated circulating levels have been documented in cancer-associated cachexia, cardiovascular and metabolic stress states, and pregnancy, where high early-pregnancy levels are linked to the severity of nausea and vomiting, including hyperemesis gravidarum.

GDF15’s role as a p53-inducible cellular stress signal has extended its research relevance beyond cancer cachexia into obesity and metabolic disease, where GDF15/GFRAL-pathway agonists are being explored as a complement to GLP-1 therapies for appetite and weight regulation — a fast-growing area of pharmaceutical interest.

Principle of the Assay

This kit uses a sandwich enzyme immunoassay format in which the microtiter plate wells are pre-coated with a capture antibody specific to Human GDF15. Standards or samples are added to the appropriate wells, followed by an HRP-conjugated detection antibody also specific to Human GDF15. Upon addition of TMB substrate solution, only wells containing the target analyte bound to the HRP-conjugated antibody produce a colorimetric signal. The enzymatic reaction is stopped by the addition of sulfuric acid stop solution, and absorbance is measured at 450 nm (± 10 nm). Sample concentrations are determined by comparing the optical density of each sample against a standard curve generated from the provided GDF15 standards.