Sigma-Aldrich Anti-Siglec-15 Clone Mk4.5 25 Mig

Siglec-15 (UniProt: A7E1W8; also known as SIGLEC-I, Sialic acid binding Ig-like lectin 15) is encoded by the Siglec15 gene (Gene ID: 620235) in mouse. SIGLEC15 is a single-pass type I membrane protein that is synthesized with a signal peptide (aa 1-23), which is subsequently cleaved off to produce the mature protein that contains an extracellular domain (aa 24-342), a transmembrane domain (aa 263-283). In human Siglec-15 (UniProt: Q6ZMC9; also known CD33 antigen-like 3) expression is observed in macrophages and dendritic cells of spleen and lymph nodes. Siglec-15 serves as an immune checkpoint molecule and a critical immune suppressor. It suppresses antigen-specific T cell responses in vitro and in vivo. Genetic ablation or antibody blockade of SIGLEC15 is reported to amplify anti-tumor immunity in the tumor microenvironment and inhibits tumor growth in murine models. SIGLEC15-deficient mice also exhibit decreased serum IL-10 levels. Siglec-15 is suggested to be a potential regulator of osteoporosis, cancer, and some infectious diseases. The study with this MK4.5 mouse monoclonal antibody demonstrated an almost exclusive Siglec-15 expression on murine osteoclasts and hardly any other expression on various other immune cell types whereas, human Siglec-15 was more broadly expressed on human myeloid cells, including human osteoclasts. Findings suggest a role of Siglec-15 as a regulator of pathologic bone resorption in arthritis and highlight its potential as a target for future therapies. This MK4.5 antibody has been validated in Flow cytometry and Immunofluorescence. (Ref.: Korn, M.A., et Al. (2020). J Immunol. 205(10):2595-2605).

Murine Siglec-15 Fc fusion protein.

Quality Control Testing

Evaluated by Flow Cytometry in RAW 264.7 cells.

Flow Cytometry Analysis: 1.0 µg from a representative lot detected Siglec-15 in one million RAW 264.7 cells treated with 180 ng/mL of human TNF-related activation-induced cytokine (TRANCE) for 4 days.

Tested Applications

Immunofluorescence Analysis: A representative lot detected Siglec-15 in Immunofluorescence application (Korn, M.A., et Al. (2020). J Immunol. 205(10):2595-2605).

Flow Cytometry Analysis: A representative lot detected Siglec-15 in Flow Cytometry application (Korn, M.A., et Al. (2020). J Immunol. 205(10):2595-2605).

Note: Actual optimal working dilutions must be determined by end user as specimens, and experimental conditions may vary with the end user

Clone MK4.5 is a mouse monoclonal antibody that specifically detects Siglec-15. It targets an epitope within an Extracellular Ig-like 1-2 domain.

Purified mouse monoclonal antibody IgG1 in buffer containing 0.1 M Tris-Glycine (pH 7.4), 150 mm NaCl with 0.05% sodium azide.

0.5 mg/mL. Please refer to guidance on suggested starting dilutions and/or titers per application and sample type.

Recommended storage: +2°C to +8°C.

Concentration: Please refer to the Certificate of Analysis for the lot-specific concentration.

Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals.