Chemokine ligand 10 (CXCL10), also known as interferon-gamma-induced protein 10 (IP-10) or small inducible cytokine B10, is a low-molecular-weight cytokine belonging to the CXC chemokine family. It can be secreted by various types of cells, including monocytes, endothelial cells, and fibroblasts. CXCL10/IP-10 has multiple functions, such as chemotaxis for monocytes/macrophages, T cells, NK cells, and dendritic cells, promoting T cell adhesion to endothelial cells, exhibiting anti-tumor activity, and inhibiting bone marrow colony formation and angiogenesis

This assay kit employs the double antibody sandwich enzyme-linked immunosorbent assay (ELISA) technique. Specific anti-human CXCL10/IP-10 antibodies with high affinity are pre-coated onto the enzyme-linked plate. In the wells of the enzyme-linked plate, standards, test samples, and biotinylated detection antibodies are added. After incubation, CXCL10/IP-10 present in the samples binds to the solidphase antibody and the detection antibody, forming an immune complex. After removing unbound substances, streptavidin-horseradish peroxidase labeled with horseradish peroxidase (HRP) is added. After wash step to remove any unbound substances, 3,3′,5,5′-Tetramethylbenzidine (TMB)substrate is added and color develops in proportion to the amount of CXCL10/IP-10 bound initially. The assay is stopped, and the optical density of the wells is determined using a micro-plate reader at 450nm wavelength (with a reference wavelength of 540nm or 570nm) for quantification.

Recovery
Human CXCL10/IP-10 of different levels was spiked into cell culture medium samples to determine its recovery rate. The recovery rate ranged from 78-114%, with an average recovery rate of 93%.
Sensitivity
The minimum detectable dose (MDD) of Human CXCL10/IP-10 is typically less than 3.50 pg/mL.
The MDD was determined by adding two standard deviations to the mean O.D. value of ten zero standard replicates and calculating the corresponding concentration.
Linearity
To assess the linearity of the assay, four samples spiked with high concentrations of Human CXCL10/IP-10 were diluted with 1×Reagent Diluent to bring them within the detection range.

Specificity
This assay recognizes natural and recombinant Human CXCL10/IP-10.
The factors listed below were prepared at 50 ng/mL in 1×Reagent Diluent and assayed for cross-reactivity.
Preparations of the following factors prepared at 50 ng/mL in a mid-range Human CXCL10/IP-10 were assayed for interference. No significant cross-reactivity or interference was observed.