Recombinant human CD44 Protein, 100µg

Background
CD44 antigen is a cell-surface glycoprotein involved in cell–cell interactions, cell adhesion and migration. CD44 is expressed in a large number of mammalian cell types. CD44 is a receptor for hyaluronic acid and can also interact with other ligands, such as osteopontin, collagens, and matrix metalloproteinases (MMPs). CD44 function is controlled by its posttranslational modifications. One critical modification involves discrete sialofucosylations rendering the selectin-binding glycoform of CD44 called HCELL (for Hematopoietic Cell E-selectin/L-selectin Ligand). CD44 participates in a wide variety of cellular functions including lymphocyte activation, recirculation and homing, hematopoiesis, and tumor metastasis. Transcripts for this gene undergo complex alternative splicing that results in many functionally distinct isoforms.

Source
Recombinant Human CD44 Protein (rhCD44) Gln 21 - Pro 220 (Accession # AAH04372) was produced in human 293 cells (HEK293).

Molecular Characterization
This protein carries a polyhistidine tag at the C-terminus.
The protein has a calculated MW of 22.9 kDa. The protein migrates as 35-58 kDa under reducing (R) condition (SDS-PAGE) due to glycosylation.

Endotoxin
Less than 1.0 EU per μg of the rhCD44 by the LAL method.

Purity
>95% purity as determined by SDS-PAGE.

Formulation
Lyophilized from 0.22 μm filtered solution in PBS, pH7.4. Normally Mannitol or Trehalose are added as protectants before lyophilization.

Reconstitution
See Certificate of Analysis for details of reconstitution instruction and specific concentration.

Storage
Avoid repeated freeze-thaw cycles. No activity loss was observed after storage at:
In lyophilized state for 1 year (4°C-8°C); After reconstitution under sterile conditions for 1 month (4°C-8°C) or 3 months (-20°C to -70°C).

References

(1) Goodison S., et al., 1999, MP, Mol. Pathol. 52 (4): 189–96.
(2) Hanley WD., et al., 2005, Cancer Res. 65 (13): 5812–7.
(3) Burdick MM., et al., 2006, J. Biol. Chem. 281 (20): 13899–905.
(4) Thomas SN., et al., 2008, J Biol Chem 283 (23): 15647–55.