Background:Flt-3 Ligand
Flt-3 Ligand, also known as FL, is an alpha-helical cytokine that promotes the differentiation of multiple hematopoietic cell lineages. Mature human Flt-3 Ligand consists of a 158 amino acid (aa) extracellular domain (ECD) with a cytokine-like domain and a juxtamembrane tether region, a 21 aa transmembrane segment, and a 30 aa cytoplasmic tail. Within the ECD, human Flt-3 Ligand shares 71% and 65% aa sequence identity with mouse and rat Flt-3 Ligand, respectively. Human and mouse Flt-3 Ligand show cross-species activity. Flt-3 Ligand is expressed as a noncovalently-linked dimer by T cells and bone marrow and thymic fibroblasts. Each 36 kDa chain carries approximately 12 kDa of N- and O-linked carbohydrates. Alternate splicing and proteolytic cleavage of the transmembrane form can generate a soluble 30 kDa fragment that includes the cytokine domain. Alternate splicing of human Flt-3 Ligand also generates membrane-associated isoforms that contain either a truncated cytoplasmic tail or an 85 aa substitution following the cytokine domain. Both transmembrane and soluble Flt-3 Ligand signal through the tyrosine kinase receptor Flt-3/Flk-2. Flt-3 Ligand induces the expansion of monocytes and immature dendritic cells as well as early B cell lineage differentiation. It synergizes with IL-3, GM-CSF, and SCF to promote the mobilization and myeloid differentiation of hematopoietic stem cells. It cooperates with IL-2, -6, -7, and -15 to induce NK cell development and with IL-3, -7, and -11 to induce terminal B cell maturation. Animal studies also show Flt-3 Ligand to reduce the severity of experimentally induced allergic inflammation.
原厂资料:
Product Summary:
The Quantikine Mouse/Rat Flt-3 Ligand Immunoassay is a 4.5 hour solid phase ELISA designed to measure mouse or rat Flt-3 Ligand levels in cell culture supernates and serum. It contains NS0-expressed recombinant mouse Flt-3 Ligand and antibodies raised against the recombinant protein. Results obtained for naturally occurring mouse or rat Flt-3 Ligand showed linear curves that were parallel to the standard curves obtained using the Quantikine kit standards. These results indicate that this kit can be used to determine relative mass values of natural mouse/rat Flt-3 Ligand.
Precision:
Intra-Assay Precision (Precision within an assay)Three samples of known concentration were tested on one plate to assess intra-assay precision.
Inter-Assay Precision (Precision between assays)Three samples of known concentration were tested in separate assays to assess inter-assay precision.
Cell Culture Supernates, Serum
Intra-Assay Precision
Inter-Assay Precision
Sample
1
2
3
1
2
3
n
20
20
20
20
20
20
Mean
79.5
237
775
82.4
242
768
Standard Deviation
3.9
10.1
28.6
6.2
13.6
39.4
CV%
4.9
4.3
3.7
7.5
5.6
5.1
Recovery:
The recovery of mouse Flt-3 Ligand spiked to three levels throughout the range of the assay in various matrices was evaluated.
Sample Type
Average % Recovery
Range %
Mouse Cell Culture Supernates (n=5)
99
88-107
Rat Cell Culture Supernates (n=5)
108
99-119
Mouse Serum (n=5)
95
82-106
Rat Serum (n=5)
95
86-114
Linearity:
To assess the linearity of the assay, five or more samples containing and/or spiked with various concentrations of mouse Flt-3 Ligand in each matrix were diluted with Calibrator Diluent and then assayed.