CD28 a 44 kD glycoprotein, is a member of the Ig superfamily, expressed on thymocytes, most peripheral T cells, and NK cells, acting as a co-stimulatory receptor of T cell activation. CD28 is expressed on resting T-cells, while the co-inhibitory receptor CTLA-4 is expressed as a on activated T-cells. Both molecules bind CD80 and CD86 on antigen presenting cells, but CTLA4 has higher affinity then CD28. Anti-CD28 along with anti-CD3 can also activate T cells in vitro.

Each lot of antibody has been tested by flow cytometry staining. We suggest use ≤ 0.5 µg per million cells in 100 µl volume of staining buffer. Researchers are recommended to further titrate this antibody at the optimal concentration for each specific application.

Store at 2 °C ~ 8 °C, protected from prolonged light exposure. DO NOT FREEZE.