FITC-Labeled Siglec-2/CD22 Protein, Human (HEK293, Fc)

The Siglec-2/CD22 protein mediates B cell interactions and may direct B cell localization within lymphoid tissues. It recognizes sialylated glycoproteins, especially α-2,6-linked sialic acid, and participates in cis-interactions at the cell surface. Siglec-2/CD22 Protein, Human (FITC, HEK293, Fc) is the recombinant human-derived Siglec-2/CD22 protein, expressed by HEK293 , with C-hFc labeled tag.

Siglec-2/CD22 Protein serves as a crucial mediator in B-cell interactions, potentially playing a role in the localization of B-cells within lymphoid tissues. Known for its ability to bind sialylated glycoproteins, including CD45, it exhibits a preference for alpha-2,6-linked sialic acid. The sialic acid recognition site may be masked by cis interactions with sialic acids on the same cell surface. During the immune response, ligand-induced tyrosine phosphorylation suggests its involvement in the regulation of B-cell antigen receptor signaling. The protein's multifaceted role encompasses positive regulation through interaction with Src family tyrosine kinases, while concurrently acting as an inhibitory receptor by recruiting cytoplasmic phosphatases via their SH2 domains to block signal transduction through dephosphorylation of signaling molecules. Siglec-2/CD22 predominately exists as a monomer of isoform CD22-beta and can also form a heterodimer with a shorter isoform. Its intricate interactions with key molecules such as PTPN6/SHP-1, LYN, SYK, PIK3R1/PIK3R2, PLCG1, GRB2, INPP5D, and SHC1, especially upon phosphorylation, highlight its pivotal role in orchestrating complex signaling networks within B-cells. Further research is essential to unravel the precise molecular pathways and functional consequences of Siglec-2/CD22 in B-cell regulation and immune responses.

Human

HEK293

C-hFc

P20273 (D20-R687)

933  [NCBI]

Extracellular Domain

DSSKWVFEHPETLYAWEGACVWIPCTYRALDGDLESFILFHNPEYNKNTSKFDGTRLYESTKDGKVPSEQKRVQFLGDKNKNCTLSIHPVHLNDSGQLGLRMESKTEKWMERIHLNVSERPFPPHIQLPPEIQESQEVTLTCLLNFSCYGYPIQLQWLLEGVPMRQAAVTSTSLTIKSVFTRSELKFSPQWSHHGKIVTCQLQDADGKFLSNDTVQLNVKHTPKLEIKVTPSDAIVREGDSVTMTCEVSSSNPEYTTVSWLKDGTSLKKQNTFTLNLREVTKDQSGKYCCQVSNDVGPGRSEEVFLQVQYAPEPSTVQILHSPAVEGSQVEFLCMSLANPLPTNYTWYHNGKEMQGRTEEKVHIPKILPWHAGTYSCVAENILGTGQRGPGAELDVQYPPKKVTTVIQNPMPIREGDTVTLSCNYNSSNPSVTRYEWKPHGAWEEPSLGVLKIQNVGWDNTTIACAACNSWCSWASPVALNVQYAPRDVRVRKIKPLSEIHSGNSVSLQCDFSSSHPKEVQFFWEKNGRLLGKESQLNFDSISPEDAGSYSCWVNNSIGQTASKAWTLEVLYAPRRLRVSMSPGDQVMEGKSATLTCESDANPPVSHYTWFDWNNQSLPYHSQKLRLEPVKVQHSGAYWCQGTNSVGKGRSPLSTLTVYYSPETIGRR

Approximately 130-140 kDa,based on SDS-PAGE under reducing conditions,due to the glycosylation.

≥ 95%, as determined by Bis-Tris PAGE.

<1 EU/μg, determined by LAL method.