title: Label-Free Imaging of Histamine Mediated G Protein-Coupled Receptors Activation in Live Cells.
abstract: G protein-coupled receptors (GPCRs) are the largest protein family for cell signal transduction, and most of them are crucial drug targets. Conventional label-free assays lack the spatial information to address the heterogeneous response from single cells after GPCRs activation. Here, we reported a GPCRs study in live cells using plasmonic-based electrochemical impedance microscopy. This label-free optical imaging platform is able to resolve responses from individual cells with subcellular resolution. Using this platform, we studied the histamine mediated GPCRs activation and revealed spatiotemporal heterogeneity of cellular downstream responses. Triphasic responses were observed from individual HeLa cells upon histamine stimulation. A quick peak P1 in less than 10 s was attributed to the GPCRs triggered calcium release. An inverted P2 phase within 1 min was attributed to the alternations of cell-matrix adhesion after the activation of Protein Kinase C (PKC). The main peak (P3) around 3-6 min after the histamine treatment was due to dynamic mass redistribution and showed a dose-dependent response with a half-maximal effective concentration (EC50) of 3.9 ± 1.2 μM. Heterogeneous P3 responses among individual cells were observed, particularly at high histamine concentration, indicating diverse histamine H1 receptor expression level in the cell population.
authors: Biodesign Center for Bioelectronics and Biosensors, Arizona State University , Tempe, Arizona 85287, United States.|Department of Chemistry, Beijing Key Laboratory for Microanalytical Methods and Instrumentation, Tsinghua University , Beijing 100084, China.
authors: Jin
authors: J
authors: Lu
authors: Biodesign Center for Bioelectronics and Biosensors, Arizona State University , Tempe, Arizona 85287, United States.|School of Electrical Computer and Energy Engineering, Arizona State University , Tempe, Arizona 85287, United States.
authors: Yunze
authors: Y
authors: Yang
authors: Biodesign Center for Bioelectronics and Biosensors, Arizona State University , Tempe, Arizona 85287, United States.
authors: Wei
authors: W
authors: Wang
authors: Department of Chemistry, Beijing Key Laboratory for Microanalytical Methods and Instrumentation, Tsinghua University , Beijing 100084, China.
authors: Jinghong
authors: J
authors: Li
authors: Biodesign Center for Bioelectronics and Biosensors, Arizona State University , Tempe, Arizona 85287, United States.|School of Electrical Computer and Energy Engineering, Arizona State University , Tempe, Arizona 85287, United States.
authors: Nongjian
authors: N
authors: Tao
authors: Biodesign Center for Bioelectronics and Biosensors, Arizona State University , Tempe, Arizona 85287, United States.
authors: Shaopeng
authors: S
authors: Wang
mesh_terms: D002470:Cell Survival; D017097:Electric Impedance; D055664:Electrochemical Techniques; D006367:HeLa Cells; D006632:Histamine / Q000032:analysis* / Q000378:metabolism; D006801:Humans; D061848:Optical Imaging; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D014407:Tumor Cells, Cultured
chemical_list: D043562:Receptors, G-Protein-Coupled; D006632:Histamine