{"product_id":"cst-16399s","title":"CST,  16399S, Phospho-CD28 (Tyr191) (E5B9Z) Rabbit Monoclonal Antibody","description":"Monoclonal Antibody for studying CD28 (Tyr191) phosphate. Validated for Western Blotting,Immunoprecipitation. Available in 2 sizes. Highly specific and rigorously validated in-house, Phospho-CD28 (Tyr191) (E5B9Z) Rabbit Monoclonal Antibody (CST #16399) is ready to ship.\n\n\u003cb\u003eProduct Usage Information\u003c\/b\u003e\nWestern Blotting: 1:1000\nImmunoprecipitation: 1:200\n\u003cb\u003eStorage\u003c\/b\u003e\nSupplied in 10 mM sodium HEPES (pH 7.5), 150 mM NaCl, 100 µg\/ml BSA, 50% glycerol and less than 0.02% sodium azide. Store at -20°C. Do not aliquot the antibody.\n\u003cb\u003eProtocol\u003c\/b\u003e\nAvailable protocols: Western Blotting, Immunoprecipitation\n\u003cb\u003eSpecificity \/ Sensitivity\u003c\/b\u003e\nPhospho-CD28 (Tyr191) (E5B9Z) Rabbit Monoclonal Antibody recognizes endogenous levels of CD28 protein only when phosphorylated at Tyr191. This antibody shows cross-reactivity with phosphorylated EGFR, ERBB2, and CSF1R, and detects a 70-80 kDa band of unknown origin in some treated cell lines.\nSpecies Reactivity: Human, Mouse\n\u003cb\u003eSource \/ Purification\u003c\/b\u003e\nMonoclonal antibody is produced by immunizing animals with a synthetic peptide corresponding to residues surrounding Tyr191 of human CD28 protein.\n\u003cb\u003eBackground\u003c\/b\u003e\nCD28 is a transmembrane glycoprotein expressed by T cells as well as some other hematopoietic cells (1, 2). T cell activation requires T cell receptor (TCR) recognition of antigen presented in the context of MHC molecules. CD28 acts as a T cell costimulatory receptor, and interaction of CD28 with its ligands CD80 or CD86 provides the second signal required for naïve T cell activation (3-5). Activation of naïve T cells in the absence of CD28 stimulation can result in a state of T cell anergy, or unresponsiveness (3). CD28 signals through cytoplasmic phospho-tyrosine motifs that bind several SH2 or SH3 domain-containing proteins involved in T cell activation (2). Recently, CD28 was demonstrated to be a preferred target of PD-1-mediated dephosphorylation. Consistently, CD28 expression was required for T cell proliferation following PD-1 blockade and CD28 stimulation was required for effective anti-PD-1 cancer immunotherapy in mice (6, 7). Several CD28 isoforms are produced by alternative splicing (8).\n\u003cb\u003eAlternate Names\u003c\/b\u003e\nCD28; CD28 antigen; CD28 molecule; MGC138290; T-cell-specific surface glycoprotein CD28; TP44\n\n\u003cb\u003eSpecification\u003c\/b\u003e\n\nREACTIVITY: H M\nSENSITIVITY: Endogenous\nMW (kDa): 40\nSource\/Isotype: Rabbit IgG","brand":"CST","offers":[{"title":"Default Title","offer_id":46797630341289,"sku":"16399S","price":0.99,"currency_code":"USD","in_stock":true}],"url":"https:\/\/iright.com\/products\/cst-16399s","provider":"Iright","version":"1.0","type":"link"}