Measuring NAADP-Evoked Ca²⁺ Release in Permeabilized T Cells

Nicotinic acid adenine dinucleotide phosphate (NAADP) is a highly potent Ca²⁺ releasing second messenger with a distinct role during early T cell activation. While studies have proposed NAADP signaling in T cells as a target for treating autoimmune diseases, there are currently no pharmacologic inhibitors available for clinical trial. This is in part due to the fact, that investigating NAADP-evoked Ca²⁺ signals in T cells currently requires laborious techniques such as microinjections. We have combined recent advances on NAADP signaling to develop a protocol for measuring NAADP-evoked Ca²⁺ release from permeabilized T cells, that can be used to further characterize this pathway in T cells and validate new pharmacologic agents.