Shop Now Contact

Mouse CD200 (OX-2) Protein (C-His-Avi)

Mouse CD200 (C-His-Avi) on SDS-PAGE under reducing condition (P+) and non-reducing condition (P-). The gel was stained for 1 hour with BlinkBlue (catalog 700102). The purity of this protein appears to be greater than 95% based on reducing conditions.

Cat #	Size	Price	Quantity
815601	25 ug	$145
815602	100 ug	$295

Bulk/Custom

Product Details

Application	ELISA, BLI
Format	Liquid, Purified
Expression Host	CHO
Target Name	CD200, MOX1, MOX2, MRC, OX-2, My033
Species	Mouse
Sources	Recombinant Mouse CD200 (Gln31-Gly232) with C-terminus His-Avi-tag is expressed in CHO cell.
Accession Number	O54901
Molecular Weight	The protein has a predicted molecular weight of 26.1 kDa. Under DTT-reducing conditions, it migrates at approximately 45 kDa on SDS-PAGE.
Affinity Tag	C-His-Avi
Purity	>95% based on SDS-PAGE under reducing condition
Regulatory Status	RUO
Formulation	1xPBS buffer, pH7.4, 0.22 µm filtered
Endotoxin level	Not tested
Protein Concentration	25µg size is bottled at 0.2mg/mL concentration. 100 µg size is supplied at a lot-specific concentration.
Storage and Handling	Briefly centrifuge the vial upon receipt. An unopened vial can be stored at 4°C for up to 2 weeks, or at -20°C or below for up to six months. The protein may be further diluted to 0.1 mg/mL using 0.22 µm-filtered PBS buffer (pH 7.4). For long-term storage, the diluted stock solution should be aliquoted and stored at ≤ –70°C to minimize freeze-thaw cycles. If additional dilution is required, carrier proteins such as FBS or BSA should be added to maintain protein stability.
Research Areas	B cells, Neurons, vacular endothelial cells, Cancer Marker, Immune Homeostasis

Background Information

CD200, also known as OX-2, is an immunoregulatory cell surface glycoprotein that plays a key role in maintaining immune tolerance and limiting inflammatory responses. It is broadly expressed on a variety of cell types, including thymocytes, B cells, activated T cells, dendritic cells, endothelial cells, neurons, and certain tumor cells. CD200 functions primarily by delivering inhibitory signals to myeloid lineage cells, thereby suppressing excessive immune activation and protecting tissues from immune-mediated damage.

Structurally, CD200 is a type I transmembrane protein belonging to the immunoglobulin superfamily. It consists of two extracellular immunoglobulin-like domains (one variable-like and one constant-like), a single transmembrane helix, and a short cytoplasmic tail that lacks known signaling motifs. Unlike many immune receptors, CD200 does not signal intracellularly through its own cytoplasmic domain. Instead, its biological effects are mediated through engagement of its receptor, CD200R, which is expressed predominantly on macrophages, monocytes, dendritic cells, mast cells, and some T cell subsets.

The primary ligand for CD200 is CD200R (CD200 receptor), an inhibitory receptor containing cytoplasmic signaling motifs that recruit adaptor proteins and downstream inhibitory pathways. Binding of CD200 to CD200R suppresses pro-inflammatory cytokine production, reduces antigen presentation capacity, and promotes an anti-inflammatory or tolerogenic phenotype in myeloid cells. This interaction is particularly important in immune-privileged sites such as the central nervous system, where CD200 expression on neurons helps restrain microglial activation.

Dysregulation of CD200 signaling has been implicated in several diseases. Overexpression of CD200 is observed in various malignancies, including chronic lymphocytic leukemia (CLL), multiple myeloma, and certain solid tumors, where it contributes to immune evasion by suppressing antitumor immunity. Conversely, insufficient CD200 signaling may exacerbate autoimmune or inflammatory conditions due to unchecked myeloid activation.

Therapeutically, CD200 is being explored as a target in oncology and immune modulation. Blocking antibodies against CD200 aim to restore antitumor immune responses by relieving myeloid suppression. In contrast, agonistic strategies enhancing CD200–CD200R signaling are being investigated for inflammatory and autoimmune diseases. By modulating innate immune checkpoints, CD200 represents a promising target for rebalancing immune responses in diverse clinical settings.

Frequently Asked Questions

How is a fluorescence labeled recombinant protein different from a labeled antibody for the same target?

A labeled protein (e.g., a fluorescent ligand or receptor domain) binds its natural counter-receptor or binding partner directly, making it useful for functional binding assays, competition/blocking studies, and receptor occupancy measurements — whereas an antibody typically binds a specific epitope regardless of the protein's natural binding activity. Choose the labeled protein format when you need to assess biologically relevant binding interactions rather than simple target detection.

Can these proteins be used in flow cytometry, and are they compatible with other panel reagents?

Yes, fluorescence labeled proteins are commonly used in flow cytometry panels to detect receptor expression or ligand binding on live cells, and are designed to be compatible with standard antibody panels. As with any multicolor panel, confirm spectral compatibility and run proper compensation controls when combining labeled proteins with labeled antibodies.

What controls should I use with fluorescence labeled recombinant proteins?

Recommended controls include an unlabeled/unconjugated version of the same protein (for competition/blocking controls), an irrelevant labeled protein of the same conjugate as a background control, and standard unstained/FMO controls for gating. Species- or format-matched controls are noted on the product page where available.

What applications are these proteins validated for?

Common applications include receptor binding assays, flow cytometry-based ligand-receptor studies, ELISA-based detection, and blocking/competition assays to study receptor occupancy or antagonist activity. Specific validated applications and recommended usage concentrations vary by product and are detailed on the individual product page.

Have a product or application question? Consult our FAQs or contact us.

Search Tips