CUSABIO’s Human glial fibrillary acidic protein (GFAP) ELISA Kit is an in vitro enzyme-linked immunosorbent assay for the quantitative measurement of human GFAP in serum, plasma, and tissue homogenates. GFAP is a type III intermediate filament protein uniquely present in astrocytes of the central nervous system (CNS), non-myelinating Schwann cells in the PNS, and enteric glial cells. It is used as a classical marker for astrocytes in the vertebral CNS. And it plays a role in the de-differentiation of the axon and is responsible for the cytoskeleton structure of glial cells and for maintaining their mechanical strength, as well as supporting neighboring neurons and the blood-brain barrier (BBB). The expression of GFAP is significantly increased during the chronic inflammation of Rheumatoid Arthritis (RA), an autoimmune inflammatory disease that damages systemic joints.

This kit has many advantages including high sensitivity, excellent specificity, precision less than 10%, high recovery, good linearity, and high consistency between batches. The assay employs the quantitative sandwich enzyme immunoassay technique. Standards and samples are pipetted into the wells and any GFAP present is bound by the anti-GFAP antibody pre-coated onto the microplate. After removing any unbound substances, the biotin-conjugated GFAP antibody is added to the wells. HRP-avidin and the TMB substrate solution are respectively added to the wells in-order. The solution color develops in proportion to the amount of GFAP bound in the initial step. The color development is stopped and the intensity of the color is measured at 450 nm via a microplate reader.