Serum thrombospondin-2 (TSP-2 or THBS2) is a glycoprotein expressed in the extracellular matrix (ECM), which increases during tissue remodeling. It is a potential risk factor in heart disease.  Gene expression population studies point to the TSP2 gene as significantly upregulated in NAFLD and NASH populations.  These studies have been further explored with TSP2 protein in serum samples of NASH human subjects and show a correlation with NASH activity and fibrosis.  The ImmunoDiagnostics Human TSP2 ELISA kit is one of the commercial kits being used and published in clinical studies to date.

PRINCIPLE OF THE ASSAY

This assay is a quantitative sandwich enzyme-linked immunosorbent assay (ELISA). The microtiter plate is pre-coated with a monoclonal antibody specific for human TSP-2. Standards and samples are pipetted into the wells and any human TSP-2 present is bound by the immobilized antibody. After washing away any unbound substances, a biotin labelled polyclonal antibody specific for human TSP-2 is added to the wells. After wash step to remove any unbound reagents, streptavidin-horseradish peroxidase (HRP) conjugate (STP-HRP) is added. After the last wash step, an HRP substrate solution is added and color develops in proportion to the amount of human TSP-2 bound initially. The assay is stopped, and the optical density of the wells is determined using a microplate reader. Since the increases in absorbance are directly proportional to the amount of captured human TSP-2, the unknown sample concentration can be interpolated from a reference curve included in each assay.

Each kit is sufficient for one 96-well plate and contains the following components:

  1. Microtiter Strips (96 wells), coated with a monoclonal antibody against human TSP-2, sealed
  2. 10×Wash buffer, 50 mL
  3. 5×Assay buffer, 20 mL
  4. 100×Detection antibody solution, a biotin labelled polyclonal antibody against human TSP-2, 0.12 mL
  5. Human TSP-2 standard, 10 ng of recombinant human TSP-2, lyophilized
  6. 200×STP-HRP solution, 0.06 mL
  7. Substrate solution, 12 mL, ready for use
  8. Stop solution, 12 mL, ready for use

Samples:  serum or plasma samples

Sample volume:  100 uL, serum or plasma sample generally requires a 2-fold dilution

Species:  Human

Detection Range:  0.156 – 10 ng/mL

Sensitivity:  0.156 ng/mL

Run time:  < 4 hours

Storage:  2-8°C upon receipt, and all reagents should be equilibrated to room temperature before use