CDx Antibodies | Emerging Targets B7-H3/H4, Facilitating ADC Drug Development
06 Aug 2025
B7-H3
B7-H3 (also known as CD276) is a type I transmembrane protein and a newly identified member of the B7 family of immune regulatory proteins. It has emerged as a key target in cancer immunotherapy because of its overexpression in tumor tissues and limited expression in normal tissues, thereby contributing to the shaping and development of the tumor microenvironment (TME). To date, numerous B7-H3 -based immunotherapeutic strategies have demonstrated effective antitumor activity and acceptable safety profiles in preclinical models.
Numerous studies have shown that B7-H3 is overexpressed in many types of tumors. It is not expressed or is expressed at low levels in lymphocytes but exhibits increased expression upon induction. These expression patterns suggest that B7-H3 may play an important role in tumor development and cancer immunology.
Figure 1. The role of B7-H3 in the TME
Targeting B7-H3 via ADCC
Antibody-dependent cellular cytotoxicity (ADCC) targeting B7-H3
Antibody-drug conjugate (ADC) therapies targeting B7-H3 combine the target specificity of monoclonal antibodies (mAbs) with cytotoxic drugs, thereby delivering cytotoxic agents to tumors and improving therapeutic indices.
Currently, more than 90 clinical trials have been or are being conducted to evaluate the safety and efficacy of B7-H3 -targeted antibodies, bispecific antibodies, ADCs, and CAR-T -based immunotherapeutic strategies.
Figure 2. B7-H3 -based tumor immunotherapy strategies
B7-H4
B7-H4 is a transmembrane protein and an important member of the B7 family. It can bind to an unknown receptor on activated T cells, thereby inhibiting T cell effector functions through cell cycle arrest, reduced proliferation, and decreased IL-2 production. B7-H4 is upregulated on cancer cells and immunosuppressive tumor-associated macrophages (TAMs) in various human cancers. Notably, B7-H4 expression levels are negatively correlated with patient survival in ovarian cancer, cholangiocarcinoma, breast cancer, and endometrial cancer, making B7-H4 a novel biomarker or therapeutic target for treating tumors, inflammation, autoimmune diseases, and organ transplantation.
Figure 3. Blocking the B7-H4: B7-H4R interaction
StarMab® Related Products
B7H3, an emerging target in immune checkpoint therapy, has brought another member of the B7 family, B7H4, into the spotlight. The future trend in tumor immunotherapy will involve studying cell therapies for different organoids based on the new targets B7-H3 and B7-H4.
StarMab Bio stays at the forefront of target information and has developed a series of B7-H3/H4 antibodies and protein products to facilitate the development of antibody drugs.
StarMab® B7-H3
Antibody Name: S-RMab® B7-H3/CD276 Recombinant Rabbit mAb (SDT-R158)
Tissue Type: Human colorectal cancer, human breast cancer
IHC Staining Localization: Cell membrane
Recommended Catalog Number: S0B2169
Antibody Type: Recombinant rabbit monoclonal antibody
StarMab® B7-H4
Antibody Name: B7-H4 Recombinant Rabbit mAb (SDT-314-447)
Tissue Type: Human breast cancer, human ovarian cancer
IHC Staining Localization: Cell membrane
Recommended Catalog Number: S0B2234
Antibody Type: Recombinant rabbit monoclonal antibody
Click on the product catalog numbers below to be redirected to the official website for more details.
Product Information
| Gatalog Num | Product Name | Product Parameters | Price |
| S0B2235 | B7-H4 Recombinant Rabbit mAb (SDT-314-447-2) | Host : Rabbit | Inquiry |
| Conjugation : Unconjugated | |||
| S0B2234 | B7-H4 Recombinant Rabbit mAb (SDT-314-447) | Host : Rabbit | Inquiry |
| Conjugation : Unconjugated | |||
| S0B2169 | S-RMab®B7-H3/CD276 Recombinant Rabbit mAb (SDT-R158) | Host : Rabbit | Inquiry |
| S0B2244 | B7-H3 Recombinant Rabbit mAb (SDT-249-26) | Host : Rabbit | Inquiry |
| Conjugation : Unconjugated | |||
| S0B2245 | CD11c Recombinant Rabbit mAb (SDT-396-48) | Host : Rabbit | Inquiry |
| Conjugation : Unconjugated | |||
| S0B2247 | S-RMab® S100B Recombinant Rabbit mAb (SDT-518-45) | Host : Rabbit | Inquiry |
| Conjugation : Unconjugated | |||
| S0B2248 | S-RMab® ATRX Recombinant Rabbit mAb (SDT-458-37) | Host : Rabbit | Inquiry |
| Conjugation : Unconjugated | |||
| S0B2249 | Glutamine Synthetase (GS) Recombinant Rabbit mAb (SDT-549-25) | Host : Rabbit | Inquiry |
| Conjugation : Unconjugated | |||
| S0B2250 | Villin Recombinant Rabbit mAb (SDT-R255) | Host : Rabbit | Inquiry |
| Conjugation : Unconjugated | |||
| S0B2251 | SAGE1 Recombinant Rabbit mAb (SDT-317-60) | Host : Rabbit | Inquiry |
| Conjugation : Unconjugated |
