Allison Ebert, from the Medical College of Wisconsin, described methods for generating astrocyte cultures of improved purity from hiPSCs. In contrasting other recent reports (Emdad et al., 2012, Krencik et al., 2011, Serio et al., 2013), she noted the lengthy duration of existing protocols, which required months to differentiate and expand astrocytes, and she reported on recent attempts to use magnetic activated cell sorting (MACS)-based methods, and even simple cellular passaging, to positively select for astrocyte fate within weeks. Despite some successes, she challenged the field to thoughtfully consider which type of astrocyte each protocol in fact yields and the relevance of these astrocytes to those occurring in vivo. Ebert closed by discussing recent findings from hiPSC astrocyte studies regarding the cell non-autonomous effects underlying reduced synaptic puncti in spinal muscular atrophy (SMA) hiPSC-derived motor neurons (Ebert et al., 2009, Sareen et al., 2012). SMA is a genetic childhood disease characterized by motor neuron loss that is believed to be due to a reduction in the amount of survival motor neuron (SMN) protein in motor neurons. She reported that astrocyte
