Humanized Anti-Human CD28 mAb
Catalog Number: TL-102
Product name
Generic names: Humanized Anti-Human CD28 mAb
Product information
Species Reactivity: Human
Specificity: Detects human CD28 in direct ELISAs and Western blots. In direct ELISAs, approximately 20% crossreactivity with recombinant mouse CD28 is observed
Source: CHO cells
QC Testing Purity: > 95 % as determined by SDS-PAGE
Purification: Protein A purified from cell culture supernatant
Immunogen: Recombinant human CD28
Endotoxin: Level <0.1 EU/μg
Formulation: Lyophilized from a 0.2 μm filtered solution in PBS with HSA
Stability & Storage: Samples are stable for up to 24 months from date of receipt at 4 ℃. Avoid repeated freeze-thaw cycles.
Applications: 1. ELISA(recommended concentration 1:5000-1:10000). 2. T Cell Stimulation: This antibody can be used to activate T cells when immobilized at 1-10
μg/mL (100 μL/well).
Background
CD28 and CTLA-4, together with their ligands, B7-1 and B7-2, constitute one of the dominant costimulatory pathways that regulate T and B cell responses. CD28 and CTLA-4 are structurally homologous molecules that are members of the immunoglobulin (Ig) gene superfamily. Both CD28 and CTLA-4 are composed of a single Ig Vlike extracellular domain,a transmembrane domain and an intracellular domain. CD28 and CTLA-4 are both expressed on the cell surface asdisulfide-linked homodimers or as monomers. The genes encoding these two molecules are closely linked on human chromosome 2 and mouse chromosome 1. Mouse CD28 is expressed constitutively on virtually 100% of mouse T cellsand on developing thymocytes. Cell surface expression of mouse CD28 is down-regulated upon ligation of CD28 in thepresence of PMA or PHA. In contrast, CTLA-4 is not expressed constitutively but is up-regulated rapidly following Tcell activation and CD28 ligation. Cell surface expression of mouse CTLA-4 peaks approximately 48 hours afteractivation. 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. CD28/B7 interaction has been shown to prevent apoptosis of activated T cells viathe upregulation of Bcl-xL. CD28 ligation has also been shown to regulate Th1/Th2 differentiation.
BEIJING T&L BIOLOGICAL TECHNOLOGY CO.,LTD. For research use only.
References
1. Lenschow, D.J. et al. (1996) Annu. Rev. Immunol. 14:233.
2. Hathcock, K.S. and R.J. Hodes (1996) Advances in Immunol. 62:131.
3. Ward, S.G. (1996) Biochem. J. 318:361.
Trial dosage: A customer can apply for up to five samples a year (the actual trial dosage is determined by telephone or email communication).
Scope of use: Samples are limited to testing and research purposes.
Cost: Free for samples, customer is responsible for shipping and handling charges, reference cost is $50 in the US, €60 in the EU, and $50 in other countries.
How to apply: You can apply by telephone or by email (the email application should specify the sample name, item number, contact person, telephone number, consignee address, etc.).
