Intended Use
The Human CD200 ELISA Pair Set is for the quantitative determination of Human CD200.
Contents of Kit
Capture Antibody - 0.5 mg/mL of Rabbit anti-CD200 monoclonal antibody (in PBS, pH 7.4). Dilute to a working concentration of 1 μg/mL in PBS before coating.
Detection Antibody - 0.2 mg/mL rabbit anti-CD200 polyclonal antibody conjugated to horseradishperoxidase (HRP) (in PBS, 50 % HRP-protector, pH 7.4). Dilute to a working concentration of 0.5 μg/mL in detection antibody dilution buffer before use.
Standard - Each vial contains 190 ng of recombinant CD200. Reconstitute with 1 mL detection antibody dilution buffer. After reconstitution, store at -20°C to -70°C in a manual defrost freezer. A seven-point standard curve using 2-fold serial dilutions in sample dilution buffer, and a high standard of 2 ng/mL is recommended.
Storage
Capture Antibody: Aliquot and store at -20°C to -70°C for up to 6 months from date of receipt. Avoid repeated freeze-thaw cycles.
Detection Antibody: Store at 4°C and protect it from prolonged exposure to light for up to 6 months from date of receipt. DO NOT FREEZE!
Standard: Store lyophilized standard at -20°C to -70°C for up to 6 months from date of receipt. Aliquot and store the reconstituted standard at -20°C to -70°C for up to 1 month. Avoid repeated freeze-thaw cycles.
Sensitivity
The minimum detectable dose of Human CD200 was determined to be approximately 31.25 pg/ml. This is defined as at least three times standard deviations above the mean optical density of 10 replicates of the zero standard.
General Description
CD200, also known as OX-2, is a transmembrane immunoregulatory protein belonging to the immunoglobulin superfamily. The human CD200 cDNA encodes a 278 aa precursor that includes a 30 aa signal sequence, a 202 aa extracellular domain (ECD), a 27 aa transmembrane segment, and a 19 aa cytoplasmic domain. The ECD is composed of one Ig-like V-type domain and one Ig-like C2-type domain, and shares 76% aa sequence identity with mouse and rat CD200. CD200 interacts with a structurally related receptor (CD200R) expressed mainly on myeloid cells and is involved in regulation of macrophage and mast cell function. CD200 and CD200R associate via their respective Nterminal Ig-like domains. In myeloid cells, CD200R initiates inhibitory signals following receptor-ligand contact. In T cells, CD200 functions as a costimulatory molecule independent of the CD28 pathway. In addition, CD200 also plays an important role in prevention of graft rejection, autoimmune diseases and spontaneous abortion.