Hippocampal reactive neural stem cells are able to phagocytose and have an immunological molecular signature

Abiega, O.; Senovilla-Ganzo, R.; El-Ouraoui, M.; Muro, T.; Ruiz, L.; Fitzsimons, C. P.; Martin Suarez, S.; Encinas Perez, J. M.

doi:10.1101/2024.01.26.577346

bioRxiv · 10.1101/2024.01.26.577346

Hippocampal reactive neural stem cells are able to phagocytose and have an immunological molecular signature

Abiega, O.·Senovilla-Ganzo, R.·El-Ouraoui, M.·Muro, T.·Ruiz, L.·Fitzsimons, C. P.·Martin Suarez, S.·Encinas Perez, J. M.

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Abstract

Hippocampal neural stem cells (NSCs) are the drivers of neurogenesis in the dentate gyrus (DG) of most mammals including humans. During neuronal hyperactivity NSCs become reactive NSCs (react-NSCs), characterized by their activation, morphological changes, and symmetric division, abandoning their neurogenic programme and transforming into reactive astrocytes. Here, using different pathological models that induce react-NSCs in the DG, we looked for novel features of react-NSCs both histologically and by total RNA sequencing. We report that in two pathological models were react-NSCs emerge (mesial temporal lobe epilepsy (MTLE) and traumatic brain injury (TBI)) react-NSCs are capable of phagocytosis of dead cells, a typical immunological function carried out mainly by microglia in the brain. Importantly, MTLE-induced react-NSCs show phagocytic function in tissue and a predominantly immunological molecular signature, with a broad upregulation of phagocytosis-related gene expression. Our results describe a new function of react-NSCs as phagocytic and immunologically active cells in the hippocampal neurogenic niche.

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Abiega, O., Senovilla-Ganzo, R., El-Ouraoui, M., Muro, T., Ruiz, L., Fitzsimons, C. P., Martin Suarez, S., Encinas Perez, J. M.. 2024-01-26. Hippocampal reactive neural stem cells are able to phagocytose and have an immunological molecular signature. https://doi.org/10.1101/2024.01.26.577346

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