title: Endogenous gustatory responses and gene expression profile of stably proliferating human taste cells isolated from fungiform papillae.
abstract: Investigating molecular mechanisms underlying human taste sensation requires functionally dedicated and at the same time proliferating human taste cells. Here, we isolated viable human fungiform taste papillae cells from biopsy samples, adenovirally transduced proliferation promoting genes, and obtained stably proliferating cell lines. Analysis of gene expression of 1 human taste cell line termed HTC-8 revealed that these cells express 13 TAS2R bitter taste receptor genes, CD36, OXTR encoding oxytocin receptor, as well as genes implicated with signal transduction and cell fate control. Bitter tastants triggered functionally distinct signaling pathways in HTC-8 cells. Salicin elicited phospholipase C-dependent calcium signaling and no cell depolarization. In contrast, stimulation with saccharin, aristolochic acid, or phenylthiocarbamide triggered cell depolarization and phospholipase C-independent calcium influx. Simultaneous stimulation with salicin and saccharin revealed that saccharin can enhance the phospholipase C-dependent response to salicin indicating crosstalk of signaling pathways. Our results show that HTC-8 cells are programmed to bitter taste reception but are also responsive to fatty acids, oxytocin, and somatosensory stimuli, whereas HTC-8 cells are insensitive to compounds representing other basic taste qualities.
authors.affiliation: BRAIN AG, Darmstaedter Str. 34-36, 64673 Zwingenberg, Germany. ah@brain-biotech.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Hochheimer
authors.forename: Michael
authors.initials: M
authors.lastname: Krohn
authors.forename: Kerstin
authors.initials: K
authors.lastname: Rudert
authors.forename: Katja
authors.initials: K
authors.lastname: Riedel
authors.forename: Sven
authors.initials: S
authors.lastname: Becker
authors.forename: Christian
authors.initials: C
authors.lastname: Thirion
authors.forename: Holger
authors.initials: H
authors.lastname: Zinke
mesh_terms: D034341:Aristolochic Acids / Q000494:pharmacology; D001592:Benzyl Alcohols / Q000494:pharmacology; D018955:CD36 Antigens / Q000235:genetics / Q000378:metabolism; D020013:Calcium Signaling / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D005960:Glucosides / Q000494:pharmacology; D006801:Humans; D010670:Phenylthiourea / Q000494:pharmacology; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism; D018045:Receptors, Oxytocin / Q000235:genetics / Q000378:metabolism; D012439:Saccharin / Q000494:pharmacology; D015398:Signal Transduction / Q000235:genetics; D013650:Taste Buds / Q000166:cytology* / Q000378:metabolism*; D000098706:Taste Receptors, Type 2
chemical_list: D034341:Aristolochic Acids; D001592:Benzyl Alcohols; D018955:CD36 Antigens; D005960:Glucosides; C569600:OXTR protein, human; D043562:Receptors, G-Protein-Coupled; D018045:Receptors, Oxytocin; C431926:taste receptors, type 1; D000098706:Taste Receptors, Type 2; C005696:salicin; D010670:Phenylthiourea; C000228:aristolochic acid I; D012439:Saccharin
keywords: bitter taste; gustatory signaling; human taste cell biology; primary taste cell; taste modulation; taste receptor