Cat. No.
MABL-1009
Application
Block, ELISA, FC
Isotype
Engineer antibody
Species Reactivity
Human
Clone No.
h4C1
From
Recombinant Antibody
Specificity
This antibody binds the FG loop of the human CD47, which interacts with SIRPα and several other known CD47/SIRPα-blocking mAb. CD47 is broadly distributed on normal adult tissues, as well as ovarian tumors, and is especially abundant in some epithelia and the brain. IAP or integrin assocaited protein has a role in both cell adhesion by acting as an adhesion receptor for THBS1 on platelets, and in the modulation of integrins. It further plays an important role in memory formation and synaptic plasticity in the hippocampus. It also acts as a receptor for SIRPA. Binding to SIRPA prevents maturation of immature dendritic cells and inhibits cytokine production by mature dendritic cells.
Alternative Names
IAP; MER6; OV-3; Leukocyte surface antigen CD47; Antigenic surface determinant protein OA3; Integrin-associated protein; Protein MER6; ovarian cancer marker; 4C1
UniProt
Q08722
Immunogen
The original mouse antibody was generated by immunizing BALB/c mice with human CD47- ecto recombinant protein emulsified with complete Freund's adjuvant. Later on the original mouse antibody was used to generate the humanized version of the antibody using sequence homology and computational prediction.
Application Notes
This antibody specifically binds to the CD47 molecule to block the binding of CD47 to SIRPα, thereby activating macrophages and killing tumor cells. The blocking activity was demonstrated using flow cytometry assay. This antibody also bound CD47 ectodomain in an ELISA. Surface plasmon resonance (SPR)-binding assays demonstrated that h4C1 bound to the human CD47-ECD antigen with a KD of 0.85 nM. Macrophage-mediated phagocytosis activity was investigated by a tumor cell phagocytosis assay with bone marrow-derived macrophages (BMDMs) and tt was reported that h4C1 exhibited significant phagocytosis in Raji cells. In in vivo experiments this antibody improved survival and enhanced suppression of Raji cell xenografts in mice (PMID" 32296041). This antibody was also used in the generation of a bispecific antibody (BsAb) in a dual-variable-domain immunoglobulin (DVD-Ig) format targeting CD47 and PD-L1. The variable-domain from the PD-L1-blocking mAb #18 was introduced in tandem onto h4C1 to generate a dual variable domain bsAb that binds bivalently to both CD47 and PD-L1. This BsAb retained retained blocking activity for both interactions but lacked the hemagglutinating activity of the parental m4C1 (PMID: 32296041; 33244513).
Antibody First Published
Shi et al. The identification of a CD47-blocking "hotspot" and design of a CD47/PD-L1 dual-specific antibody with limited hemagglutination. Signal Transduct Target Ther. 2020 Mar 6;5(1):16. PMID:32296041
Note on publication
Describes the generation of a bispecific antibody targeting CD47 and PD-L1 using this 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.
