CD22 is a B-lineage restricted 135 kDa glycoprotein whose cell surface expression is limited to resting and activated B lymphocytes. The physiological role of CD22 is still unknown. Targeted disruption of CD22 in mice results in a reduced level of surface IgM on peripheral B cells, suggesting a role for CD22 in limiting antigen receptor signaling. CD22 is a member of the Ig gene superfamily that uniquely binds a sialic acid-dependent ligand. Recombinant Human CD22 is a soluble 75.0 kDa protein which corresponds to the extracellular domain of CD22.

Source: CHO cells

Synonyms: soluble CD22, Leu-14, B-lymphocyte cell adhesion molecule, BL-CAM, Siglec-2

AA Sequence: SKWVFEHPET LYAWEGACVW IPCTYRALDG DLESFILFHN PEYNKNTSKF DGTRLYESTK DGKVPSEQKR VQFLGDKNKN CTLSIHPVHL NDSGQLGLRM ESKTEKWMER IHLNVSERPF PPHIQLPPEI QESQEVTLTC LLNFSCYGYP IQLQWLLEGV PMRQAAVTST SLTIKSVFTR SELKFSPQWS HHGKIVTCQL QDADGKFLSN DTVQLNVKHT PKLEIKVTPS DAIVREGDSV TMTCEVSSSN PEYTTVSWLK DGTSLKKQNT FTLNLREVTK DQSGKYCCQV SNDVGPGRSE EVFLQVQYAP EPSTVQILHS PAVEGSQVEF LCMSLANPLP TNYTWYHNGK EMQGRTEEKV HIPKILPWHA GTYSCVAENI LGTGQRGPGA ELDVQYPPKK VTTVIQNPMP IREGDTVTLS CNYNSSNPSV TRYEWKPHGA WEEPSLGVLK IQNVGWDNTT IACARCNSWC SWASPVALNV QYAPRDVRVR KIKPLSEIHS GNSVSLQCDF SSSHPKEVQF FWEKNGRLLG KESQLNFDSI SPEDAGSYSC WVNNSIGQTA SKAWTLEVLY APRRLRVSMS PGDQVMEGKS ATLTCESDAN PPVSHYTWFD WNNQSLPHHS QKLRLEPVKV QHSGAYWCQG TNSVGKGRSP LSTLTVYYSP ETIGRR

Purity: ≥ 98% by SDS-PAGE gel and HPLC analyses.

Biological Activity: Determined by its ability to inhibit the proliferation of Raji cells. The expected ED₅₀ for this effect is 10-17 μg/ml.