CD28 Bioassay, Propagation Model
The CD28 Bioassays are bioluminescent cell-based assays used to measure the potency and stability of ligands or antibodies that activate CD28. CD28 binds to the B7 family members CD80 and CD86 (collectively referred to as B7 for this bioassay) on antigen-presenting cells (APCs). Co-stimulation of T cells by CD28 activation initiates signaling cascades that result in AP-1 and NFkappaB transcription factor activation and nuclear translocation. These pathways significantly enhance T cell cytokine production (specifically interleukin-2 [IL-2]), which promotes T cell proliferation, differentiation and survival.Antibodies that agonize CD28 have the potential to enhance immune responses against cancer and chronic infection. The CD28 Bioassay Core Kit reflects the mechanism of action (MOA) of biologics designed to activate CD28.