Differentiation of KISS1-Expressing Cells from Human Pluripotent Stem Cells: Many Roads To Rome
This study presents two effective strategies for differentiating human pluripotent stem cells into KISS1-expressing neurons, which could enhance our understanding of human reproductive biology.
Where it sits
this study against the rest of the kisspeptin (kp-10) corpusSummary and findings
This study measured the differentiation of human pluripotent stem cells into neuron cultures expressing KISS1. Two distinct strategies were employed: the FGF8 protocol and the SHH protocol. Both strategies resulted in significant KISS1 expression in the neuron cultures.
Abstract
<h4>Introduction: </h4> Kisspeptin-secreting (Kiss) neurons govern human puberty and reproduction. In the arcuate nucleus (ARC), they control pulsatile release of gonadotropin-releasing hormone (GnRH), while Kiss neurons in the preoptic area (POA) control GnRH surge. Since animal models do not fully recapitulate the human phenotype, a human model to study these neurons is crucial. Methods We differentiated human pluripotent stem cells (hPSCs) into neuron cultures using two distinct strategies: FGF8 protocol, consisting of dual SMAD inhibition (dSMADi), FGF8b, and Notch inhibition; and SHH protocol, consisting of dSMADi and SHH activation, followed by Notch inhibition. Neuron cultures obtained on day 45 were characterized at the mRNA level using RT-qPCR. Results Both strategies resulted in neuron cultures where significant KISS1 expression could be detected. SHH-derived neuron cultures expressed high NKX2-1 and the ARC markers POMC, NHLH2, and NR5A2, while FGF8-derived neuron cultures expressed low NKX2-1 and the anterior POA marker FOXG1. Conclusions We provide the first ever strategies to differentiate hPSCs into neuron cultures that express KISS1. Future studies providing in depth transcriptomic, protein, and functional characterization are needed to establish the properties of these models.
Background
This paper addresses the differentiation of KISS1-expressing neurons from human pluripotent stem cells, which is crucial for understanding human puberty and reproduction. Previous studies have relied on animal models that do not fully mimic human physiology, highlighting the need for human-specific models. The differentiation of these neurons could provide insights into the mechanisms governing gonadotropin-releasing hormone (GnRH) release.
Methods
The study utilized two differentiation strategies: the FGF8 protocol involving dual SMAD inhibition, FGF8b, and Notch inhibition, and the SHH protocol involving dual SMAD inhibition and SHH activation followed by Notch inhibition. Neuron cultures were characterized at the mRNA level using RT-qPCR on day 45. The primary outcome measure was the expression of KISS1 and other neuronal markers.
Results
Both differentiation strategies resulted in significant KISS1 expression in the neuron cultures. SHH-derived cultures showed high expression of NKX2-1 and markers associated with the arcuate nucleus, while FGF8-derived cultures exhibited low NKX2-1 levels and expressed the anterior preoptic area marker FOXG1.
Interpretation
The results indicate successful differentiation of hPSCs into KISS1-expressing neurons, which may advance the understanding of Kisspeptin's role in human physiology. However, the clinical significance of these findings remains unclear, as the study does not report quantitative measures or functional assessments. Limitations include the lack of detailed characterization and potential confounding factors related to the protocols used.
Key findings
- Significant KISS1 expression detected in both FGF8 and SHH-derived neuron cultures.
- SHH-derived cultures expressed high NKX2-1 and ARC markers POMC, NHLH2, and NR5A2.
- FGF8-derived cultures expressed low NKX2-1 and anterior POA marker FOXG1.
Limitations
- Not reported in abstract.
- No quantitative measures or functional assessments provided.
- Limited characterization of neuron cultures.