Obtaining such proliferating taste cell lines has in the past been hampered by the fact that taste cells are functionally specialized cells with limited life span and no proliferative potential, which are embedded in the context of a taste bud. This group of researchers delivers hTERT and BMI1 via adenovirus and obtains stably proliferating cell lines, which originated from individual cells and were expanded separately.
With cell lines stable for more than 25 passages the group could investigate expression of taste reception and signal transduction genes and measure endogenous responses to chemical stimuli in cell-based assays. They found that HTC-8 cells express 13 of 25 human TAS2R bitter taste receptor genes.