B7-H3 Protein

B7-H3 Protein Overview

B7-H3 reagents

Costimulatory B7 molecules (e.g., B7-1, or CD80; 112203) signal through CD28 (186760) family molecules, such as CD28, CTLA4 (123890), and ICOS (604558). By searching sequence databases with the extracellular regions of B7 family members, Chapoval et al. (2001) identified a cDNA encoding CD276, which they called B7H3, in a dendritic cell (DC) cDNA library. Sequence analysis predicted that the 316-amino acid type I transmembrane protein contains an N-terminal signal peptide; extracellular V- and C-like Ig domains with 4 conserved cysteine residues; a transmembrane region; and a 45-amino acid cytoplasmic tail. The extracellular receptor-binding domain of B7H3 shares 27% and 25% identity with those of B7H1 (605402) and B7H2 (605717), respectively. Northern blot analysis detected highest expression of a 4.1-kb transcript in heart, liver, placenta, prostate, testis, uterus, pancreas, small intestine, colon, and lymphoid organs, with lower expression in brain, skeletal muscle, kidney, and lung, and no expression in peripheral blood leukocytes. B7H3 expression was detected in most tumor cell lines tested. Sun et al. (2002) identified a mouse homolog of B7H3. By probing an EST database using mouse B7h3, they identified a human B7H3 variant, which they termed B7H3b, that has a different N-terminal sequence. RT-PCR analysis detected wide expression of both B7H3 isoforms. B7H3b was the major isoform in all tissues examined except brain and placenta. Using monoclonal antibodies reacting with monocyte-derived DCs, retroviral expression cloning, and flow cytometric analysis, Steinberger et al. (2004) obtained a cDNA identical to the B7H3 cDNA reported by Chapoval et al. (2001) at its 5-prime end. However, full-length DNA sequence analysis indicated that B7H3 encodes a 534-amino acid protein with a short leader sequence and 4, rather than 2, Ig-like domains, followed by a transmembrane domain and a short cytoplasmic tail. RT-PCR and EST database analyses showed that only the 1.3-kb transcript corresponding to the larger molecule was expressed in various tissues and cell lines. Western blot analysis revealed strong expression of a 110-kD protein corresponding to the larger molecule in both mature and immature DCs.

B7-H3 protein family

Belongs to the immunoglobulin superfamily. BTN/MOG family.

B7-H3 protein name

Recommended name
CD276 antigen
B7H3, B7-H3, B7RP-2
Alternative name
4Ig-B7-H3 B7 homolog 3 B7-H3 Costimulatory molecule CD antigen CD276

B7-H3 Gene family protein

B7-H3 Protein Sequence

Species Human B7-H3 protein
Length 534
Mass (Da) 57235
Sequence Human B7-H3 protein sequence
Species Mouse B7-H3 protein
Length 316
Mass (Da) 34001
Sequence Mouse B7-H3 protein sequence
Species Rat B7-H3 protein
Length 316
Mass (Da) 34075
Sequence Rat B7-H3 protein sequence

B7-H3 Protein Molecular Weight & PI

CD276 antigen precursor (4Ig-B7-H3) (B7 homolog 3) (B7-H3) (Costimulatory molecule) Homo sapiens (Human).

The parameters have been computed for the following feature

FT CHAIN 29-534 CD276 antigen.

Molecular weight (Da)


Theoretical pI


B7-H3 Protein Interaction

Recombinant B7-H3 Protein Feature

B7-H3 Protein, Human, Recombinant (His Tag)

High Purity
> 98 % as determined by SDS-PAGE
Low Endotoxin
< 1.0 EU per μg of the protein as determined by the LAL method

Bulk Order of Recombinant B7-H3 Protein

Please Leave Us a Message if you have any questions regarding bulk price quote of our products on the website, our customer specialist will get back to you in 24 hours by email.

Custom Recombinant Protein Production Service Features

  • Over 10 years' experience for 6000+ recombinant proteins production.
  • One-stop service from gene synthesis and vector construction to protein expression and purification.
  • Multiple protein expression systems: bacterial, yeast, baculovirus-insect and mammalian expression system.
  • Multiple purification systems (30+) to choose.
  • High R & D ability with over 1000 new proteins per year and quick problem-solving ability.
  • Close to 100 bioreactors with various volume between 2-1000 L to guarantee high-throughput and large-scale production.

Custom Recombinant Protein Production Service Advantages

  • High-efficiency expression vectors
  • High cell density culturing
  • Proprietary medium formulation
  • >6000 proteins expression and purification experience
  • High-efficiency expression vectors
  • High cell density culturing

Recombinant Protein Production Service Description

We offer one-stop services for recombinant protein production using our advanced protein expression platform technologies. Our full services include protein gene synthesis, protein codon optimization, protein expression vector design, large scale cell culture and fermentation, protein purification, and protein quality control testing. We offer significant cost saving advantages and record speed in protein expression and bulk production. We also have extensive experiences and expertise in handling various types of recombinant protein purification projects, with or without purification tags.