Astrocytes and microglia are able to degrade potentially neurotoxic β-amyloid (Aβ) deposits typical for Alzheimer's disease (AD) pathology. Contrary to microglia, astrocytes degrade human Aβ from tissue sections in vitro without any additional stimulation, but it has remained unclear whether transplanted astrocytes are able to clear deposited human Aβ in vivo. We transplanted adult mouse astrocytes into the hippocampi of transgenic mice mimicking AD and observed their fate, effects on microglial responses, and Aβ clearance. After 2-months follow-up time, we discovered a significant reduction in Aβ burden compared with AD mice infused with PBS only. The remaining Aβ deposits were fragmented and most of the Aβ immunoreactivity was seen within the transplanted astrocytes. Concomitant to Aβ reduction, both CD68 and CD45 immunoreactivities were significantly upregulated but phagocytic microglia were often surrounding and engulfing Aβ burdened, TUNEL-positive astrocytes rather than co-localizing with Aβ alone. Astrocytes are known to degrade Aβ also by secreting proteases involved in Aβ catabolism. To study the contribution of neprilysin (NEP), angiotensin-converting enzyme-1 (ACE-1), and endothelin-converting enzyme-2 (ECE-2) in human Aβ clearance, we utilized an ex vivo assay to demonstrate that adult astrocytes respond to human Aβ by upregulating NEP expression. Further, incubation of adult astrocytes with known inhibitors of NEP, ACE-1, or ECE-2 significantly inhibited the removal of human Aβ from the tissue suggesting an important role for these proteases in Aβ clearance by adult astrocytes ex vivo.

Transplantation of human neural progenitor cells (hNPCs) is a promising therapeutic approach for various diseases of the central nervous system (CNS). Reliable testing of hNPC transplantation in animal models of neurological diseases requires that these cells can be produced in sufficient amounts, show consistent homogeneity as a neural cell population, and be reliably labeled for in vivo tracking. In addition, the cells should be characterized as being at the optimal state of differentiation favoring successful engraftment. Here, we show that high numbers of purified hNPCs can be produced from human embryonic stem cells (hESCs) by manually selecting specifically sized and shaped spheres followed by fluorescence-activated cell sorting based on the relative cell size. In addition, we report that labeling of hNPCs with ultra-small superparamagnetic iron oxide (USPIO) particles does not affect the cellular morphology or growth. More importantly, we show that the transduction with lentiviral vector encoding green fluorescent protein (GFP) decreases the neurality of the cell population. We conclude that our cost-effective protocol of generating hNPCs is widely applicable for preclinical studies on CNS disorders. This improved method of producing large quantities of high-purity hNPCs maybe useful also when generating hNPCs from human induced pluripotent stem (hiPS) cell lines. However, caution should be used when lenti-GFP transduction is applied for hNPC labeling.

Mobile devices have become an important part of adult life, where they are now used for media consumption and creation instead of traditional telephony function only. The same trend is visible in teens and children, both of whom are using mobile devices increasingly.Naturally the extensive use of technology easily brings up new threats, especially as mobile devices are mobile, and they cannot be tied to fixed locations that could be monitored. Nevertheless, the technology may also be beneficial for communication and family life when used smartly. These positive interaction possibilities need to be highlighted, as they provide new space for innovation.Developing our understanding further in this matter requires a multidisciplinary approach. Hence we ask for contributions from several fields, such as ethnography, education and design studies. This way we can enhance dialogue and co-create new solutions together.