In this edition, we’ll discuss the controversy over direct-to-consumer stem cell sales, with Leigh Turner and Paul Knoepfler, Cell Stem Cell (00:00); how building design can impact your respiratory health, with Jordan Peccia, Trends in Microbiology (10:10); the complex link between Alzheimer’s disease and the immune system, with Morgan Sheng and Felix Yeh, Neuron (16:15); and an eye-opening look at the risky business of experimenting on yourself (25:30).