Anti-Human CD28 (Clone 9.3) – Purified No Carrier Protein

Human T lymphocytes

This recombinant monoclonal antibody is aseptically packaged and formulated in 0.01 M phosphate buffered saline (150 mM NaCl) PBS pH 7.2 - 7.4 with no carrier protein, potassium, calcium or preservatives added. Due to inherent biochemical properties of antibodies, certain products may be prone to precipitation over time. Precipitation may be removed by aseptic centrifugation and/or filtration.

Liquid

Recombinant antibodies are manufactured in an animal free facility using only in vitro protein free cell culture techniques and are purified by a multi-step process including the use of protein A or G to assure extremely low levels of endotoxins, leachable protein A or aggregates.

Functional grade preclinical antibodies may be stored sterile as received at 2-8°C for up to one year. For longer term storage, aseptically aliquot in working volumes without diluting and store at ≥ -80°C. Avoid Repeated Freeze Thaw Cycles.

Research Use Only

2 – 8° C Wet Ice

The Anti-Human CD28 Mouse IgG2a, Clone 9.3 antibody, targets human CD28

CD28, a glycoprotein weighing 44 kDa is a member of the Ig superfamily and plays a vital role, in the activation and survival of T cells^{1, 2} by enhancing the production of interleukin and the activity of T cells. CD28 is unique among B7 receptors as it is consistently expressed on T cells. The interaction between CD28 and B7 is crucial for preventing T cells from becoming anergic and unable to respond to antigen/MHC complexes highlighting its role in an immune response^3-6.

The clone 9.3 has gained recognition for its ability to stimulate the growth of human T cells in vitro making it a valuable tool for research focused on studying T cell activation and immune responses. It was developed by immunizing mice with human T cells. It has demonstrated effectiveness in inducing T cell activation and proliferation when combined with TPA thereby influencing IL 2 receptor expression and IL 2 production⁷. This clone can be utilized for staining a portion of T cells through immunofluorescence methods and has proven successful in immunoprecipitating CD28 from Jurkat cells⁸. Given its ability to activate T cells and its reactivity with CD28, the 9.3 clone stands as a resource for research.

CD28 is primarily expressed by thymocytes, most peripheral T cells, and natural killer (NK) cells.

CD80 (B7-1) and CD86 (B7-2)

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