Cat. No.
MABL-3679
Application
Blocking, IP, FC
Isotype
Engineer antibody
Species Reactivity
Human, Rhesus Monkey, Cynomolgus Monkey
Clone No.
hL22 (Epratuzumab)
From
Recombinant Antibody
Specificity
This antibody is specific for the 3rd Ig-like domain of human CD22 (epitope B), a cell surface glycoprotein present on mature B-cells and on many types of malignant B-cells.
Alternative Names
Leu14; B-cell receptor CD22; B-lymphocyte cell adhesion molecule; BL- CAM; Sialic acid-binding Ig-like lectin 2; Siglec-2; T-cell surface antigen Leu-14
UniProt
P20273
Immunogen
This antibody was prepared by the humanization of LL2 (EPB-2), a murine anti-CD22 IgG2a raised against Raji Burkitt lymphoma cells. Murine sequences comprise 5–10% of the molecule, with the remainder being human framework sequences, which greatly reduces the potential for immunogenicity (Traczewski, 2010).
Application Notes
Epratuzumab binds to the third extracellular domain of CD22, inducing CD22 phosphorylation, resulting in negative modulation of BCR activation, and rapid CD22 internalization, leading to modulation of B-cell homing (Traczewski, 2010). Initial phase II and two terminated early phase III studies suggest that the use of this antibody to treat systemic lupus erythematosus is effective and well tolerated, but both phase III trials failed to meet primary clinical efficacy endpoints. Additionally, in vitro studies and clinical trials indicate that this antibody can be used in combination therapy with another inhibitor of B-cell activity, rituximab (anti-CD20), in the treatment of non-Hodgkin lymphoma (Traczewski, 2010).
Antibody First Published
Pawlak-Byczkowska et al., Leung et al. Two new monoclonal antibodies, EPB- 1 and EPB-2, reactive with human lymphoma & Construction and characterization of a humanized, internalizing, B-cell (CD22)-specific, leukemia/lymphoma antibody, LL2 Cancer research, 15 August 1989, Vol.49(16), pp.4568-77 & Molecular Immunology, 1995, Vol.32(17), pp.1413-1427
Note on publication
Pawlak-Byczkowska et al (1989) describes the use of LL2 (EPB-2) in IHC analysis to stain malignant lymphoma tissue sections. Leung et al (1995) describes the generation of a humanized LL2 antibody.
Size
100 μg Purified antibody.
Concentration
1 mg/ml.
Purification
Protein A affinity purified
Buffer
PBS with 0.02% Proclin 300.
Storage Recommendation
Store at 4⁰C for up to 3 months. For longer storage, aliquot and store at - 20⁰C.
