• Purity

  >97%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie? Blue Staining.

• Endotoxin Level

  <0.10 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its ability to agglutinate human red blood cells. Hadari, Y.R.     et al. (2000) J. Cell Sci.     113:2385. The ED    ₅₀ for this effect is 0.5?3 μg/mL.

• Source

  E. coli-derived Ala2-Asp135

• Accession #

• N-terminal Sequence    
  Analysis

  Ala2

• Predicted Molecular Mass

  15 kDa

Carrier Free

What does CF mean?

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

What formulation is right for me?

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: Galectin-1

Galectin-1, gene name LGALS1 (lectin, galactoside-binding, soluble 1), is a 135 amino acid (aa), 14 kDa, pleiotropic, non-glycosylated, monomeric or homodimeric carbohydrate-binding protein of the prototype galectin family (1-3). Galectins lack a classical signal peptide and can be localized to the cytosolic compartments, or secreted via non-classical pathways (1). Secreted Galectin-1 has immunosuppressive and anti-inflammatory properties and suppresses acute and chronic inflammation and autoimmunity. It contributes to negative selection of developing T cells, immunosuppression by regulatory T cells, resolution of the inflammatory response, and inhibition of immune cell migration, inflammatory cytokine production, and mast cell degranulation (1, 2, 4-6). Galectin-1 preferentially binds laminin, fibronectin, 90K/Mac-2BP, CD45, CD43, CD7, CD2, CD3, integrins alpha ₄ beta ₁, alpha ₅ beta ₁ and alpha ₄ beta ₇, and ganglioside GM1 (2, 3). It is produced in a variety of tissues by cells that include endothelial cells, connective tissue fibroblasts, thymic stromal cells, tumor cells, muscle cells, platelets, regulatory T cells, and activated tissue macrophages, B cells, T cells and dendritic cells (2, 3, 6-11). Most of this expression is cytosolic. Human Galectin-1 shares 88% aa sequence identity with mouse, equine and ovine, 90% with rat, and 87% with bovine and porcine Galectin-1.  Endothelial cell surface expression, including tumor endothelial cells, is greatly increased by cell activation (9). Galectin-1 is highly expressed at the maternal-fetal interface and contributes to fetal immune privilege (5, 12). Its immunosuppressive properties appear to also allow tumor cells to evade immune detection (4, 5). It selectively controls T cell survival by inducing apoptosis of activated Th1 and Th17 cells, which express Galectin-1-binding glycans, while promoting Th2 cell survival where glycans are sialylated and less recognized (4, 13). It also induces apoptosis of immature thymocytes (3, 6). Galectin-1 secreted from bone marrow stromal cells aids B lymphocyte development by contributing to pre-B cell integrin adhesion and receptor signaling (3). The dimer form of Galectin-1 also induces neutrophil down?regulation by inducing cell surface exposure of phosphatidylserine that marks the cell for phagocytosis (14). Galectin-1 can also modulate cell-cell and cell-matrix interactions, and can promote either cell attachment or detachment depending on the cell type and developmental stage (1, 2).

• References:

1. Di Lella, S. et al. (2011) Biochemistry 50:7842.

2. Rabinovich, G.A. and J.M. Ilarregui (2009) Immunol. Rev. 230:144.

3. Rabinovich, G.A. and M. Vidal. (2011) Curr. Opin. Hematol. 18:443.

4. Cedeno-Laurent, F. and C.J. Dimitroff (2012) Clin. Immunol. 142:107.

5. Than, N.G. et al. (2012) Trends Endocrinol. Metab. 23:23.

6. Rubinstein, N. et al. (2004) Tissue Antigens 64:1.

7. Courad, P.O. et al. (1989) J. Biol. Chem. 264:1310.

8. Hirabayashi, J. et al. (1989) Biochim. Biophys. Acta 1008:85.

9. Thijssen, V.L. et al. (2008) Am. J. Pathol. 172:545.

10. Nio-Kobayashi, J. et al. (2009) J. Histochem. Cytochem. 57:41.

11. Dias-Baruffi, M. et al. (2010) Glycobiology 20:507.

12. Than, N.G. et al. (2008) Proc. Natl. Acad. Sci. USA 105:15819.

13. Toscano, M.A. et al. (2007) Nat. Immunol. 8:825.

14. Stowell, S.R. et al. (2009) J. Biol. Chem. 284:4989.

• Entrez Gene IDs:

  3956 (Human); 16852 (Mouse)

• Alternate Names:

  14 kDa laminin-binding protein; 14 kDa lectin; Beta-galactoside-binding lectin L-14-I; BHL; DKFZp686E23103; GAL1; gal-1; Galaptin; galectin 1; Galectin1; Galectin-1; GBP; HBL; HLBP14; HPL; L-14; Lactose-binding lectin 1; Lectin galactoside-binding soluble 1; lectin, galactoside-binding, soluble, 1; LGALS1; Putative MAPK-activating protein PM12; S-Lac lectin 1