Modelling monogenic epilepsy in human brain slice cultures
Faye McLeod (Newcastle University)
C44 Biomedical Sciences Building
A Snapshot seminar hosted by the School of Physiology, Pharmacology and Neuroscience
Abstract: Early infantile developmental and epileptic encephalopathies of genetic origin are devastating conditions, but the pathological mechanisms often remain obscure. A major obstacle is the difficulty of studying human cortical brain development, in utero. To date, no in vitro preparations have been developed that accurately reproduce the complex cellular networks found beyond the first trimester. To address this, we established human brain slice cultures prepared from ethically sourced, 14-17 post conception week brain tissue. The gross anatomical structures of the marginal zone, cortical plate and subplate are maintained in these cultures for several months, while new synaptic networks form. -- We used this model system to induce STXBP1 haploinsufficiency, a common genetic cause of developmental and epileptic encephalopathy. We achieved a ~50% reduction in STXBP1 expression, using a short hairpin RNA interference introduced by adeno-associated viral vectors. Loss of STXBP1 had divergent effects upon glutamatergic and GABAergic synaptic number and function, without altering subplate neurite length and number at individual neurons. At the network level, using multi-electrode array recordings and Ca2+ imaging, we show a striking reduction in the number of low frequency events and their putative correlate, synchronised calcium transients, in the subplate of slices that have reduced STXBP1 levels. In summary, we provide a critical proof-of-principle for how to investigate the aetiology of monogenic epilepsy in prenatal neurodevelopment.
Contact information
Host: Jack Mellor