Differential expression of muscarinic acetylcholine receptor subtypes in Jurkat cells and their signaling

Muscarinic acetylcholine receptors expression and signaling in the human Jurkat T cell line were investigated. Semiquantitative real-time PCR and radioligand binding studies, using a wide set of antagonist compounds, showed the co-existence of M3, M4, and M5 subtypes. Stimulation of these subpopulations caused a concentration and time- dependent activation of second messengers and ERK signaling pathways, with a major contribution of the M3 subtype in a Gq/11-mediated response. In addition, we found that T-cell stimulation leads to increased expression of M3 and M5 both at transcriptional and protein levels in a PLC/PKCθ dependent manner. Our data clarifies the functional role of AChR subtypes in Jurkat cells and pave the way to future studies on the potential cross-talk among these subpopulations and their regulation of T lymphocytes immune function.