Lentiviral microarrays for real-time monitoring of gene expression dynamics.

We developed scalable live-cell microarrays to measure gene expression dynamics in real time and in a high-throughput manner. To this end, we generated dual-promoter lentiviral vectors harboring a transcriptional regulatory element encoding for green fluorescence protein to monitor cell activation in response to exogenous stimuli and a constitutive promoter driving red fluorescence protein for internal signal normalization. Lentivirus preparations were immobilized in a microarray format and after transduction on the array surface target cells were treated with cytokines and interrogated in real time using automated fluorescence microscopy, providing rich dynamic information over a period of several days. Data normalization by red fluorescence intensity eliminated errors due to spot-to-spot variability in transduction efficiency or changes in cell proliferation upon cytokine treatment. These results suggest that the lentivirus microarray can monitor gene expression in real-time and high-throughput manner thereby providing a useful tool for quantitative measurements of gene expression dynamics.