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Rathore, G. S.

Publications and source records attributed to Rathore, G. S..

3 recordsLinked to original sources

Mapping early patterning events in human neural development usingan in-vitro microfluidic stem cell model

Stem cell models can provide insights into human brain development at embryonic stages which are normally inaccessible. We previously developed the Microfluidic Stem Cell Regionalisation (MiSTR) model, which recapitulates the rostro-caudal patterning of human neural tube through a WNT activation (WNTa) gradient. Through temporal single cell transcriptomics of rostro-caudal and dorso-ventral gradient-patterned MiSTR, we found that rostro-caudal subtypes were regionally specified and fate-determined already during the late epiblast stage, several days before onset of neuralisation at day 3-4. Rostral cells were characterised by expression of HESX1 and SHISA2 during pre-neuralisation and PAX6 during early neuralisation, whereas caudal cells expressed FST and HOXA1 during pre-neuralisation and SOX1 as the dominant neuralising factor. In contrast to the early rostro-caudal specification, response to ventralisation in telencephalic progenitors was developmentally delayed and occurred around day 9. We further uncovered temporal events in human midbrain-hindbrain boundary formation and ventral forebrain patterning, contributing new knowledge on early human neural region-specification.

neuroscience↗

Patterning effects of FGF17 and cAMP on generation of dopaminergic progenitors for cell replacement therapy in Parkinson's disease

Cell replacement therapies using human pluripotent stem cell-derived ventral midbrain (VM) dopaminergic (DA) progenitors are currently in clinical trials for treatment of Parkinsons disease (PD). Recapitulating developmental patterning cues, such as fibroblast growth factor 8 (FGF8), secreted at the midbrain-hindbrain boundary (MHB), is critical for the in vitro production of authentic VM DA progenitors. Here, we explore the application of alternative MHB-secreted FGF-family members, FGF17 and FGF18, for VM DA pro-genitor patterning. We show that while FGF17 and FGF18 both recapitulate VM DA progenitor patterning events, FGF17 induced expression of key VM DA progenitor markers at higher levels than FGF8 and transplanted FGF17-patterned progenitors fully reversed motor deficits in a rat PD model. Early activation of the cAMP pathway mimicked FGF17-induced patterning, although strong cAMP activation came at the expense of EN1 expression. In summary, we identified FGF17 as a promising candidate for more robust VM DA progenitor patterning, with the potential to improve cell products for treatment of PD. Summary statementIn this article we find that FGF17 induces high expression of key dopamine progenitor markers and that these cells can provide functional rescue in a rat model of Parkinsons disease.

developmental biology↗

Decoding morphogen patterning of human neural organoids with a multiplexed single-cell transcriptomic screen

Morphogens, secreted signalling molecules that direct cell fate and tissue development, are used to direct neuroepithelial progenitors towards discrete regional identities across the central nervous system. Neural tissues derived from pluripotent stem cells in vitro (neural organoids) provide new models for studying neural regionalization, however, we lack a comprehensive survey of how the developing human neuroepithelium responds to morphogen cues. Here, we produce a detailed map of morphogen-induced effects on the axial and regional specification of human neural organoids using a multiplexed single-cell transcriptomics screen. We find that the timing, concentration, and combination of morphogens strongly influence organoid cell type and regional composition, and that cell line and neural induction method strongly impact the response to a given morphogen condition. We apply concentration gradients in microfluidic chips or a range of static concentrations in multi-well plates to explore how human neuroepithelium interprets morphogen concentrations and observe similar dose-dependent induction of patterned domains in both scenarios. Altogether, we provide a detailed resource that supports the development of new regionalized neural organoid protocols and enhances our understanding of human central nervous system patterning.

developmental biology↗