Principle of the Assay

This assay employs the quantitative sandwich enzyme immunoassay technique. A monoclonal antibody specific for TSLP has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any TSLP present is bound by the immobilized antibody. Following incubation unbound samples are removed during a wash step, and then a detection antibody specific for TSLP is added to the wells and binds to the combination of capture antibody- TSLP in sample. Following a wash to remove any unbound combination, and enzyme conjugate is added to the wells. Following incubation and wash steps a substrate is added. A coloured product is formed in proportion to the amount of TSLP present in the sample. The reaction is terminated by addition of acid and absorbance is measured at 450nm. A standard curve is prepared from seven TSLP standard dilutions and TSLP sample concentration determined.

For Use with serum, plasma and cell culture supernatants. For Research Use Only. Not for use in diagnostic procedures.

Target Information

Thymic Stromal Lymphopoietin (TSLP) is a 23 kDa member of the IL-7 family of a-helical cytokines. It is a monomeric glycoprotein that is synthesized as a 159 amino acid (aa) precursor. TSLP appears to have species-specific functions. In mouse, TSLP was initially reported to act on NK cells, mast cells, and B cells, but this does not appear to occur in humans. In humans, TSLP is produced by a number of divergent cell types, all of which appear to target T cells, monocytes, and/or dendritic cells. On TCR-activated T cells, TSLP directly induces T cell proliferation. The significance of this direct action is unclear. On monocytes, TSLP is reported to induce the release of multiple chemokines that target CCR4, a receptor associated with the Th2 subset. TSLP is best known for its direct action on subsets of dendritic cells. In thymic medulla, Hassell’s corpuscle epithelium produces TSLP that acts on resident CD11c+ dendritic cells. This induces the expression of B7 family molecules on dendritic cells, which subsequently convert regional CD4+CD25+ (potentially) autoreactive T cells into CD4+CD25+FOXP3+ regulatory T cells. Allergen-challenged keratinocytes are also known to produce TSLP in skin where TSLP acts on Langerhans cells (CD1a+ immature dendritic cells) which then migrate to regional lymph nodes and express B7-2/CD86, CD83, high levels of MHC-II, and TARC. TARC attracts naive CD4+ T cells to the TSLP-activated Langerhans cells, and this interaction induces a Th2 phenotype. TSLP-induced Th2 cells are strong producers of IL-13, IL-5, and TNF-a, all of which promote allergic-type inflammations.

GENE ID 85480

Materials Supplied

Kit Components 96 Wells Quantity/Size
Aluminium pouches with a Microwell Plate coated with monoclonal antibody to human TSLP (8﹡12) 1 plate
Human TSLP Standard lyophilized, 500 pg/ml upon reconstitution 2 vials
Concentrated Biotin-Conjugate anti-human TSLP monoclonal antibody 2 vials
Streptavidin-HRP solution 2 vials
Standard /sample Diluent 1 bottle
Biotin-Conjugate antibody Diluent 1 bottle
Streptavidin-HRP Diluent 1 bottle
Wash Buffer Concentrate 20x (PBS with 1% Tween-20) 1 bottle
Substrate Solution 1 vial
Stop Solution 1 vial
Adhesive Films 4 pieces
Product data sheet 1 copy


Storage Store at 2 - 8°C

Performance Characteristics

REPEATABILITY The coefficient of variation of both intra-assay and inter-assay were less than 10%.
SENSITIVITY The minimum detectable dose was 4pg/mL.
ASSAY RANGE 7.8 - 500 pg/mL
SPECIFICITY This assay recognizes both natural and recombinant human TSLP. The factors listed below were prepared at 50ng/ml in Standard /sample Diluent and assayed for cross-reactivity and no significant cross-reactivity or interference was observed.
Factors assayed for cross-reactivity
Recombinant human IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-5, IL-6, IL-8, IL-9, IL-10, IL-12, IL-17, IL-22, LIF, Leptin, TNF-α, TNF-β, IFN-γ
Recombinant mouse IL-1α, IL-1β, IL-3, IL-4, IL-5, IL-6, IL-7, IL-10, IL-13, LIF, TSLP, TNF-α
Recombinant rat IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-10, Leptin, TNF-α