Recombinant human Lipocalin-2 / LCN2 Protein, His Tag, 1mg

Background
Lipocalin-2 (LCN2), also known as oncogene 24p3 or neutrophil gelatinase-associated lipocalin (NGAL), MSFI, The binding of lipocalin-2 to bacterial siderophores is important in the innate immune response to bacterial infection. Upon encountering invading bacteria the toll-like receptors on immune cells stimulate the synthesis and secretion of lipocalin-2. Secreted lipocalin-2 then limits bacterial growth by sequestering iron-containing siderophores.[1-2] Lipocalin-2 also functions as a growth factor.[2] LCN2 is strongly upregulated during inflammation and is upregulated by interleukin 1 (but not TNF alpha) in humans. There are indications that some forms of acne could be caused due to the gene not being transcribed, and that Isotretinoin corrects this.[3] NFAT3 (NFATc4)NFAT by blocking the expression of LCN2 inhibits breast carcinoma cell motility[4]. Recent studies have revealed that NGAL plays an important role in the physiopathology of chronic myeloid leukaemia (CML) mediated by BCR-ABL.

Source
Recombinant human LCN2 (rhLCN2) Gln21-Gly198 (Accession # NP_005555.2) fused with a C-terminal 6×his tag was produced in human HEK293 cells.

Molecular Characterization
This protein carries a polyhistidine tag at the C-terminus.
The protein has a calculated MW of 21.4 kDa. The protein migrates as 22-25 kDa under reducing (R) condition (SDS-PAGE) due to glycosylation.

Endotoxin
Less than 1.0 EU per 1 μg of the rhLCN2 by the LAL method.

Purity
>95% as determined by SDS-PAGE. All lots are greater than 95% pure.

Formulation
Bulk protein in a 0.22 μm filtered solution of PBS, pH 7.4 and delivered as liquid formulation or lyophilized powder. Normally 5-8% trehalose and mannitol 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) Flo TH, et al., 2004, Nature 432 (7019): 917–21.
(2) Schmidt-Ott KM, et al., 2007, J. Am. Soc. Nephrol. 18 (2): 407–13.
(3) Nelson AM, et al., 2008, J. Clin. Invest. 118 (4): 1468–78.
(4) Fougère, M, et al., 2010, Oncogene 29 (15): 2292–301.