Active Recombinant Human CD28 protein, Fc/Avi-tagged, Biotinylated

• Cat.No.: CD28-051H
• Product Overview: Biotinylated Recombinant Human CD28(Asn19-Pro152) protein, fused to Fc/Avi tag at the C-terminus, was expressed in CHO cells .

Specification

• Description: CD28 is the founding member of a subfamily of structurally homologous costimulatory or immune checkpoint molecules of the immunoglobulin (Ig) superfamily. The CD28/B7 pathway has been shown to play a central role in immune responses against infection, autoimmune diseases, and graft rejection (1). CD28 subfamily members, including ICOS, CTLA4, PD1, PD1H, and BTLA, are characterized by a single Ig V-like extracellular domain (ECD), a transmembrane domain and an intracellular domain with highly conserved tyrosine-based signaling motifs (2). CD28 and ICOS predominately enhance T-cell activation, while CTLA-4, PD-1 and BTLA are inhibitory (1-3). The mature ECD of human CD28 shares 65% and 66% amino acid sequence identity with mouse and rat CD28, respectively. CD28 and CTLA-4, together with their ligands, B7-1 and B7-2, constitute one of the dominant co-stimulatory pathways that regulate T and B cell responses. CD28 is expressed on approximately 80% of CD4+ T cells and 50% of CD8+ T cells in humans, with the proportion of CD28-positive T cells declining with age (1-4). CD28 expression has been identified on other cell lineages, including bone marrow stromal cells, plasma cells, neutrophils, and eosinophils (5). CD28 is expressed on the cell surface as a disulfide-linked homodimer and the covalent bond is required for maximum activity (6,7). Although both CTLA-4 and CD28 can bind to the same ligands, CTLA-4 binds to B7-1 and B7-2 with a 20-100 fold higher affinity than CD28. While, CD28 ligation is critical in promoting proliferation and effector function of conventional T cells, it also promotes the anti-inflammatory function of Treg cells. Thus, CD28 serves both pro- and anti-inflammatory roles depending on the cell type and context in which it is expressed (8). The CD28 pathway has effects both at amplifying signals initiated by the T cell receptor and on a variety of processes, including signaling, metabolism, transcription, epigenetic modifications, post-translational modifications, and RNA splicing (9).Our Avi-tag Biotinylated CD28 features biotinylation at a single site contained within the Avi-tag, a unique 15 amino acid peptide. Protein orientation will be uniform when bound to streptavidin-coated surface due to the precise control of biotinylation and the rest of the protein is unchanged so there is no interference in the protein's bioactivity.
• Source: CHO cells
• Species: Human
• Tag: Fc&Avi
• Predicted N Terminal: Asn19
• Form: Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose.
• Bio-activity: Measured by its binding ability in a functional ELISA. When Recombinant Human CD80 Fc Chimera Protein is immobilized at 10 µg/mL (100 µL/well), the concentration of Biotinylated Recombinant CD28 Fc Chimera Avi-tag that produces a 50% optimal binding response is found to be 0.5-3 µg/mL.
• Molecular Mass: 120-140 kDa, under non-reducing conditions
• Protein length: Asn19-Pro152
• Endotoxin: <0.10 EU per 1 μg of the protein by the LAL method.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Applications: Bioactivity
• Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.12 months from date of receipt, -20 to -70 °C as supplied.2 weeks, 2 to 8 °C under sterile conditions after reconstitution.3 months, -20 to -70 °C under sterile conditions after reconstitution.
• Reconstitution: Reconstitute at 200 μg/mL in sterile deionized water.

Gene Information

• Gene Name: CD28 CD28 molecule [ Homo sapiens ]
• Official Symbol: CD28
• Synonyms: CD28; CD28 molecule; CD28 antigen (Tp44); CD28 antigen; Tp44; MGC138290
• Gene ID: 940
• mRNA Refseq: NM_001243077
• Protein Refseq: NP_001230006
• MIM: 186760
• UniProt ID: P10747

Reviews

08/24/2021

Its unique characteristics contribute to obtaining clear and detailed structural information, enabling researchers to unravel the intricate complexities of protein interactions and conformational changes.

08/24/2021

Researchers can confidently rely on its capabilities to generate precise and significant results, enhancing the understanding of protein function and dynamics.

08/06/2021

the CD28 protein's outstanding performance in ELISA and its utility in protein electron microscopy structure analysis make it a highly recommended tool for researchers.

Q&As

Can CD28 protein be used for personalized medicine?

CD28 protein expression and function may be relevant for personalized treatment strategies in autoimmune diseases and cancer.

What are the potential clinical applications of targeting CD28 protein?

Targeting CD28 protein may have therapeutic potential in treating autoimmune diseases, cancer immunotherapy, and organ transplantation.

How does CD28 protein impact regulatory T cells (Tregs)?

CD28 signaling is important for the function and maintenance of regulatory T cells, which play a role in immune tolerance and suppression of autoimmunity.

How does CD28 protein impact cancer immunotherapy?

CD28 protein is involved in enhancing the anti-tumor immune response, making it a potential target for cancer immunotherapy.

Are there any approved therapies targeting CD28 protein?

Currently, there are no FDA-approved therapies specifically targeting CD28 protein, but research is ongoing in this area.