Sialyl-LewisX

Sialyl-Lewis X

Identifiers
CAS Number	98603-84-0 Y
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL375586 Y
ChemSpider	559072 Y
MeSH	sialyl+Lewis+X
PubChem CID	643990
InChI InChI=1S/C31H52N2O23/c1-9-18(43)21(46)22(47)28(51-9)53-24(12(5-34)32-10(2)38)25(15(42)7-36)54-29-23(48)27(20(45)16(8-37)52-29)56-31(30(49)50)4-13(40)17(33-11(3)39)26(55-31)19(44)14(41)6-35/h5,9,12-29,35-37,40-48H,4,6-8H2,1-3H3,(H,32,38)(H,33,39)(H,49,50)/t9-,12-,13-,14+,15+,16+,17+,18+,19+,20-,21+,22-,23+,24+,25+,26+,27-,28-,29-,31-/m0/s1 Y Key: LAQPKDLYOBZWBT-NYLDSJSYSA-N Y InChI=1/C31H52N2O23/c1-9-18(43)21(46)22(47)28(51-9)53-24(12(5-34)32-10(2)38)25(15(42)7-36)54-29-23(48)27(20(45)16(8-37)52-29)56-31(30(49)50)4-13(40)17(33-11(3)39)26(55-31)19(44)14(41)6-35/h5,9,12-29,35-37,40-48H,4,6-8H2,1-3H3,(H,32,38)(H,33,39)(H,49,50)/t9-,12-,13-,14+,15+,16+,17+,18+,19+,20-,21+,22-,23+,24+,25+,26+,27-,28-,29-,31-/m0/s1 Key: LAQPKDLYOBZWBT-NYLDSJSYBC
SMILES O=C(N[C@@H]1[C@@H](O)C[C@](O[C@H]1[C@H](O)[C@H](O)CO)(O[C@@H]2[C@@H](O)[C@@H](O[C@H](CO)[C@@H]2O)O[C@@H]([C@H](O[C@@H]3O[C@H]([C@@H](O)[C@@H](O)[C@@H]3O)C)[C@H](C=O)NC(=O)C)[C@H](O)CO)C(=O)O)C
Properties
Chemical formula	C31H52N2O23
Molar mass	820.744 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Sialyl Lewis^X, also known as sialyl Le^X or SLe^X, is a tetrasaccharide carbohydrate with the sequence Neu5Acα2-3Galβ1-4[Fucα1-3]GlcNAcβ- that is usually attached to O-glycans on the surface of cells. It is known to play a vital role in cell-to-cell recognition processes. It is also the means by which an egg attracts sperm; first, to stick to it, then bond with it and eventually form a zygote. The discovery of the essential role that this tetrasaccharide plays in the fertilization process was reported in August 2011.

Sialyl Lewis ^X is also one of the most important blood group antigens and is displayed on the terminus of glycolipids that are present on the cell surface. The sialyl Lewis ^X determinant, E-selectin ligand carbohydrate structure, is constitutively expressed on granulocytes and monocytes and mediates inflammatory extravasation of these cells. Resting T- and B-lymphocytes lack its expression and are induced to strongly express sialyl Lewis ^X upon activation. The sialyl Lewis ^X determinant is expressed preferentially on activated Th1 cells but not on Th2 cells.

The term Lewis in its name comes from the name of a family of people who suffered from a red blood cell incompatibility. The studies done on these individuals’ red blood cells led to the discovery of sialyl Lewis x. Sialyl Lewis x is a very important red blood cell antigen present on the glycolipids on the plasma membrane of the cell.

Defective synthesis of the sialyl Lewis ^X antigen results in immunodeficiency (leukocyte adhesion deficiency type 2). Defective synthesis can be caused by the loss of fucosyltransferase, impairing the glycosylation of the glycosphingolipid.

Sialyl Lewis x is being used in studies to fight tumors and cancer cell growth. It has been shown that there is frequent overexpression of sialyl Lewis x on cancer cells and is found on both N-glycan and O-glycans. Sialyl Lewis x is being researched with CD markers to find new ways to create biosensors for cancer cells. Also, it is being used in new ways to target cancer cells specifically for cancer treatment.

It is also being used to achieve greater rates of fertilization of eggs in women by coating the eggs with sialyl Lewis x. It plays a key role in the inflammatory response and may be used to increase the leukocyte response to infections.