Global Analyses of mRNA Expression in Human Sensory Neurons Reveals eIF5a as a Conserved Target for Inflammation-associated Pain

Abstract

Sensory neurons derived from human induced pluripotent stem cells (hiPSCs) are a promising model. One limitation posed by the use of monocultures is the loss of cellular heterogeneity found in tissues. Here we make use of high-throughput RNA sequencing to quantify gene expression in hiPSC-derived mono-cultured and co-cultured sensory neurons. The following groups were compared: human induced pluripotent stem cells (hiPSCs) prior to differentiation, mature hiPSC-derived sensory neurons, mature co-cultures containing hiPSC-derived astrocytes and sensory neurons, mouse dorsal root ganglion (DRG) tissues, and mouse DRG cultures. We find that co-culture of sensory neurons and astrocytes enhances expression of transcripts enriched in native DRG tissues. Numerous well-established genes linked to pain and most translation factors are consistently expressed in both hiPSC and mouse samples. Marker genes for various neuronal subtypes are also present in the hiPSC cultures. As a proof of concept for the potential use of the dataset for hypothesis generation, we validated the expression of eukaryotic initiation factor 5A (eIF5A) in DRG tissue and hiPSC samples. eIF5A is a unique translation factor in that it requires a post-translational hypusine modification to be active. We show that inhibition of hypusine synthesis prevents hyperalgesic priming by inflammatory mediators in vivo and diminishes hiPSC neuronal firing in vitro. In total, we present the transcriptomes of hiPSC sensory neuron models and evaluate the requirement of a functional translation factor. This work was supported by NIH grants R01NS100788 (ZTC), R01NS114018 (ZTC), and 1UG3TR003149 (BJB). Sensory neurons derived from human induced pluripotent stem cells (hiPSCs) are a promising model. One limitation posed by the use of monocultures is the loss of cellular heterogeneity found in tissues. Here we make use of high-throughput RNA sequencing to quantify gene expression in hiPSC-derived mono-cultured and co-cultured sensory neurons. The following groups were compared: human induced pluripotent stem cells (hiPSCs) prior to differentiation, mature hiPSC-derived sensory neurons, mature co-cultures containing hiPSC-derived astrocytes and sensory neurons, mouse dorsal root ganglion (DRG) tissues, and mouse DRG cultures. We find that co-culture of sensory neurons and astrocytes enhances expression of transcripts enriched in native DRG tissues. Numerous well-established genes linked to pain and most translation factors are consistently expressed in both hiPSC and mouse samples. Marker genes for various neuronal subtypes are also present in the hiPSC cultures. As a proof of concept for the potential use of the dataset for hypothesis generation, we validated the expression of eukaryotic initiation factor 5A (eIF5A) in DRG tissue and hiPSC samples. eIF5A is a unique translation factor in that it requires a post-translational hypusine modification to be active. We show that inhibition of hypusine synthesis prevents hyperalgesic priming by inflammatory mediators in vivo and diminishes hiPSC neuronal firing in vitro. In total, we present the transcriptomes of hiPSC sensory neuron models and evaluate the requirement of a functional translation factor. This work was supported by NIH grants R01NS100788 (ZTC), R01NS114018 (ZTC), and 1UG3TR003149 (BJB).