CD222 (CIMPR, cation-independent mannose 6-phosphate receptor; IGF2 receptor) is a ubiquitously expressed 250 kDa transmembrane lectin, which serves as one of the central protein transporters. No more than 10% of CD222 is present on the cell surface where it serves as a multifunctional receptor. Intracellular (major) fraction of CD222 is involved in transport of newly synthesized lysosomal enzymes modified by mannose 6-phosphate from Golgi apparatus to lysosomes. The cell surface CD222 binds and internalizes exogeneous mannose 6-phosphate-containing ligands. CD222 thus constitutively recycles between cell surface and intracellulal vesicles.
CD222 plays important roles in the organism. It is crucial for internalization and degradation of insulin-like growth factor 2, thus controling cell growth. It also complexes CD87 (urokinase-type plasminogen-activator receptor), plasminogen and latent TGF-beta, affecting their functions. CD222-mediated phagocytosis of plasminogen-coated apoptotic bodies is important for terminal phase of apoptosis. Impaired CD222 expression can indicate risk of tumor development. Last but not least CD222 serves as a receptor for heparanase and even for antigens of Listeria, and can mediate mannose 6-phosphate-dependent virus entry into various cells.
A soluble 205 kDa form of CD222 can be shedded from the cell surface into the blood, where it participates in the transport of mannose 6-phosphated proteins, and neutralizes plasminogen. This seems to be an important regulatory mechanism to inhibit angiogenesis and migration of cells. Higher levels of sCD222 have been detected in patients with liver diseases, as well as in case of breast cancer and multiple myeloma. Blocking of CD222 expression supports tumor progression.
Fig. 1: Schematic image of CD222 glycoprotein in its transmembrane form.
The mouse monoclonal antibody MEM-238 recognizes an extracellular (luminal) epitope between amino acids 192-697 of human CD222.
Workshop: HLDA VII; WS Code 70640
Applications: WB, FC(IC), FC
Available formats: 11-315-C100, 1B-315-C100, 1F-315-T100, 1P-315-T100, A6-315-T100, 1A-315-T100
The mouse monoclonal antibody MEM-240 recognizes an extracellular (luminal) epitope between amino acids 698-1262 of human CD222.
Workshop: HLDA VII; WS Code 70641
Applications: WB, FC(IC), IP, FC
Available formats: 11-790-C100, 1P-790-T100
Fig. 2: Flow cytometry analysis of cell surface-expressed CD222 in human peripheral blood using mouse monoclonal antibody MEM-238 conjugated with Alexa Fluor® 647.
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CD274 (PD-L1) glycoprotein stands at an important immunoregulatory checkpoint.
Today we introduce three mouse monoclonal antibody clones, that have been added to our portfolio: anti-human CD37 (clone MB-1), anti-human CD49e (clone SAM1), and anti-human galectin-9 (clone 9M1-3).
Mesenchymal stem cells have become a promissing topic. Here we present our antibodies to human and murine mesenchymal stem cell markers.