Description: The CD28.2 monoclonal antibody reacts with the human CD28 molecule, a 44 kDa homodimer expressed by thymocytes, mature T cells and plasma cells. CD28 is a ligand for CD80 (B7-1) and CD86 (B7-2) and is a potent co-stimulator of T cells. Signaling through CD28 augments IL-2 and IL-2 receptor expression as well as cytotoxicity of CD3-activated T cells.
Applications Reported: The CD28.2 antibody has been reported for use in flow cytometric analysis, immunoprecipitation, and immunohistochemical staining. The recommended titer for immunoprecipitation is ~2-5 µg per million cells. CD28.2 has also been reported in costimulation of T cells in in vitro functional assays. (Please use Functional Grade purified CD28.2, cat. 16-0289, in functional assays.).
Applications Tested: The CD28.2 antibody has been tested by flow cytometric analysis of normal human peripheral blood cells. This can be used at less than or equal to 1 µg per test. A test is defined as the amount (µg) of antibody that will stain a cell sample in a final volume of 100 µL. Cell number should be determined empirically but can range from 10^5 to 10^8 cells/test. It is recommended that the antibody be carefully titrated for optimal performance in the assay of interest.
Purity: Greater than 90%, as determined by SDS-PAGE.
Aggregation: Less than 10%, as determined by HPLC.
Filtration: 0.2 µm post-manufacturing filtered.
CD28 antigen is a 44 kDa disulfide linked homodimeric T cell specific surface glycoprotein. CD28 is a cell adhesion molecule of the immunoglobulin superfamily which is constitutively expressed on most peripheral blood T lymphocytes. Moreover, CD28 is the critical T cell costimulatory receptor that provides the cell the important second activation signal by binding CD80 and CD86 which are expressed by antigen presenting cells. In addition to its co-stimulation role, CD28 functions by preventing T cells from entering an anergic-hyporesponsive state or from undergoing premature apoptotic cell death. In murine peripheral lymphoid organs and in the blood, all CD4+ and CD8+ T cells express CD28. In the thymus, CD28 expression is highest on immature CD3-, CD8+ and CD4+8+ cells, and on CD4-8- cells that express alpha/beta and gamma/delta TCR. The level of CD28 on mature CD4+ and CD8+ alpha/beta TCR+ thymocytes is two- to fourfold lower than on the immature cells. Diseases associated with CD28 dysfunction include mycosis fungiodes and Sezary's Disease.
For Research Use Only. Not for use in diagnostic procedures. Not for resale without express authorization.
Protein Aliases: CD28; CD28 antigen; MGC138290; T-cell-specific surface glycoprotein CD28; TP44
Gene Aliases: CD28; Tp44
UniProt ID: (Human) Q8NI56
Entrez Gene ID: (Human) 940