CDB25:0004551 Cd200 — Cd200r4
Experimentally validated in Mouse; Orthology-inferred in Rat, Chicken, Macaque, Pig, Cow, Chimp, Horse, Marmoset, Sheep
Title
Journal:; Year Published:
Abstract
CD200 is a ligand for all members of the CD200R family of immunoregulatory molecules.
Journal of immunology, 2004; PubMed, Mus Musculus Cd200 — Mus Musculus Cd200r4
ABSTRACT: CD200Fc, a chimeric molecule including the extracellular domain of CD200 and a murine IgG2a Fc region, regulates immune responses following engagement of a cell surface receptor, CD200R, expressed on cells of the myeloid and T cell lineage. A recent report focused attention on a family of CD200Rs, but concluded that only one member used CD200 as its ligand. We have also cloned and sequenced a family of CD200Rs, but identify an amino terminus to two of the three isoforms not recognized by previous researchers. We show by FACS, using FITC-labeled CD200Fc, that COS7 cells transfected with all CD200R isoforms bind CD200 as ligand, although the functional consequences of this binding likely differs between the different isoforms. mAbs directed against the CD200 R1/R4 isoforms altered IL-2/IL-4 cytokine production and suppressed CTL responses in a fashion comparable to CD200Fc, with a significantly lesser effect seen following addition of anti-CD200 R2/R3.
New assay to detect low-affinity interactions and characterization of leukocyte receptors for collagen including leukocyte-associated Ig-like receptor-1 (LAIR-1).
European journal of immunology, 2009; PubMed, Mus Musculus Cd200 — Mus Musculus Cd200r4
ABSTRACT: Leukocyte activity is controlled by numerous interactions between membrane receptors and ligands on the cell surface. These interactions are of low affinity making detection difficult. We developed a sensitive assay that could readily detect extremely weak interactions such as that between CD200 and the activating receptor CD200RLa (K(d)>500 microM) at the protein level. We used the new technology to screen for interactions of inhibitory receptors for collagens. We confirmed that both human and mouse leukocyte-associated Ig-like receptor-1, and in addition the related inhibitory leukocyte Ig-like receptor subfamily B member 4 (CD85K, Gp49B), bound collagen specifically, whereas other cell surface proteins gave no binding. The monomeric affinities of the interactions were then determined to allow comparison with other leukocyte interactions and indicate conditions when these interactions might lead to inhibitory signals.