GM-CSFR Reporter Assay System (Human)

This Granulocyte-Macrophage Colony-Stimulating Factor Receptor (GM-CSFR) assay kit is an all-inclusive luciferase reporter assay system that includes, in addition to GM-CSFR Reporter Cells, optimized culture medium for use in reviving the cryopreserved cells, a culture medium for use in preparing test sample treatments, the physiological activator GM-CSF as a positive control, Luciferase Detection Reagents, a cell culture-ready assay plate, and a detailed protocol. INDIGO's cell-based reporter assays allow scientists to detect any biological activity that their test samples may exert against a specific receptor present in the cell. They utilize firefly luciferase reporter gene technology which provides superior precision and sensitivity. Since the receptor binding controls the expression of the luciferase reporter gene, luciferase activity in the cells can be correlated directly with the activity of the receptor. The strength of an interaction of a chemical with the target receptor is quantified using a luminometer to measure the level of light emitted. Thaw, Feed, Dose, Read Fast, reproducible, easy-to-analyze results are only four steps away Many luciferase reporter assays require the user to grow their own cells and take time to optimize the results. INDIGO's reporter cells contain the receptor of interest and the luciferase reporter gene. Reporter cells have been optimized to provide extreme sensitivity to quantify even small changes in receptor activity. With INDIGO's cell-based reporter assays, the process is as easy as Thaw, Feed, Dose, and Read. GM-CSFR Reporter Cells GM-CSFR Reporter Cells are prepared using INDIGO's proprietary CryoMite(TM) process. This proprietary cryopreservation process, enables long-term preservation of our unique reporter cells, so we can ship our cryopreserved reporter cells and assay reagents to you via overnight delivery, for your immediate use. Or, you can store the assay kits at -80°C. Once thawed, reporter cells are ready for immediate use so there is no need to take time on intermediate spin-and-wash steps, viability determinations, or cell titer adjustments. GM-CSFR Luciferase Reporter INDIGO's GM-CSFR assay kits feature a luciferase detection reagent specially formulated to provide stable light emission between 5 and 90+ minutes after initiating the luciferase reaction. Incorporating a 5-minute reaction-rest period ensures that light emission profiles attain maximal stability, thereby allowing assay plates to be processed in batch. By doing so, the signal output from all sample wells, from one plate to the next, may be directly compared within an experimental set. Human GM-CSFR Background: The glycoprotein, granulocyte-macrophage colony-stimulating factor (GM-CSF) was originally defined as a growth factor that induces the differentiation and proliferation of myeloid progenitors in response to stress, infections, and cancers. The activity of GM-CSF is mediated through binding interactions with the GM-CSF Receptor (GM-CSFR, also known as CSF2R). GM-CSFR is expressed in myeloid cells and some non-hematopoietic cells as a heterodimer comprising a ligand-specific alpha subunit and a beta subunit. The beta subunit is also shared with the heteromeric IL-3 and IL-5 receptors. GM-CSF is known to play an important role in cancer development and progression. GM-CSF stimulates the production and maturation of neutrophils, macrophages and dendritic cells that mediate the initial host responses to cancers. However, a fine balance exists. Too little GM-CSF prevents the appropriate production of innate immune cells and subsequent activation of adaptive anti-cancer immune responses. Conversely, too much GM-CSF production can exhaust immune cells and promote cancer growth. GM-CSF is also commonly described as a cytokine, and is known to contribute to chronic inflammatory diseases by stimulating the activation and migration of myeloid cells to inflammation sites. An imbalance in GM-CSF production and signaling has been associated with autoimmune diseases like multiple sclerosis (MS), rheumatoid arthritis (RA), myasthenia gravis (MG), inflammatory bowel disease (IBD) and systemic lupus erythematosus (SLE). Consequently, GM-CSF and its specific receptor, GM-CSFR, command considerable interest in therapeutics development and drug safety screening. JAK2 dependent phosphorylation and activation of the transcription factor STAT5 is a prominent outcome of GM-CSFR activation, and it is the signaling pathway exploited by the reporter cells included in this assay kit. Specifically, INDIGO's Reporter Cells contain the luciferase reporter gene functionally linked to an engineered minimal promoter sequence with upstream tandem STAT5 genetic response element (GRE) sequences. GM-CSF activates the GM-CSFR in a dose-dependent manner, thereby triggering the JAK2/STAT signal transduction cascade. Activated STAT5 binds to its consensus GREs to initiate the formation of a complete transcription complex that drives expression of the Luc reporter gene. Therefore, quantifying changes in luciferase activity from peptide-, drug- or antibody-treated reporter cells relative to that of 'untreated' cells provides a sensitive, dose-dependent surrogate measure of changes in the activity of GM-CSFR. Protein function: Low affinity receptor for granulocyte-macrophage colony- stimulating factor. Transduces a signal that results in the proliferation, differentiation, and functional activation of hematopoietic cells. [The UniProt Consortium]