CD28/TP44 (N-His) (recombinant human/cynomolgus)

Activity: Immobilized  Human/Cynomolgus CD28-His(Cat#PKSH033840) at 2µg/ml (100 µl/well) can bind Anti-CD28 mAb. The ED50 of  Anti-CD28 mAb is 15.3 ng/ml. Protein Construction: Recombinant Human T-cell-specific Surface Glycoprotein CD28 is produced by our Mammalian expression system and the target gene encoding Asn19-Pro152 is expressed with a 6His tag at the N-terminus. Sequence: Asn19-Pro152. Fusion tag: N-6His Endotoxin: < 1 IEU/µg as determined by LAL test. Apparent Molecular Mass: 30-40 kDa. Protein function: T-cell-specific surface glycoprotein CD28(CD28) is a single-pass typeI membrane protein which contains one Ig-likeV-type (immunoglobulin-like) domain. It belongs to the immunoglobulin(Ig) superfamily. CD28 is one of the molecules expressed on T cells that provide co-stimulatory signals, which are required for T cell activation.CD28 co-stimulation is necessary for CD4 positive T-cell proliferation and survival, interleukin-2 production, and T-helper type-2 development. Human post-thymic regulatory T cells require CD28 co-stimulation to expand and maintain potent suppressive function in vivo. Apoptosis plays a key role in the age-related decline of CD28 expression and in immunosenescence. CD28 is the receptor for CD80 (B7.1) and CD86 (B7.2). When activated by Toll-like receptor ligands, the CD80 expression is upregulated in antigen presenting cells (APCs). The CD86 expression on antigen presenting cells is constitutive. CD28 is the only B7 receptor constitutively expressed on naive T cells. Protein function: Involved in T-cell activation, the induction of cell proliferation and cytokine production and promotion of T-cell survival. Enhances the production of IL4 and IL10 in T-cells in conjunction with TCR/CD3 ligation and CD40L costimulation (PubMed:8617933). Isoform 3 enhances CD40L-mediated activation of NF-kappa-B and kinases MAPK8 and PAK2 in T-cells (PubMed:15067037). [The UniProt Consortium]