In amyotrophic lateral sclerosis (ALS), motor neurons that are required for muscle contractions die off, leading to progressive paralysis affecting most muscles of the body. The molecular causes of ALS are poorly understood, and effective treatments are missing.  

To study ALS in the lab, Hideyuki Okano and his colleagues from Keio University, Japan, developed a new method to make motor neurons from stem cells taken directly from ALS patients. The results were just published in the journal Stem Cell Reports.

When thinking about the immune system, most people think about B and T cells and how they can be trained to recognize pathogens, preventing re-infections. Besides this “adaptive” immune system, we also have an “innate” immune system which acts as first line defense against e.g. bacteria and viruses. The textbook view is that the innate immune system is non-specific so that it’s response always follows the same pattern, even for recurring infections. However, research published today in Stem Cell Reports provides evidence that brief exposure to certain “danger signals” can prime the body’s innate immune system into a long-term hyperreactive and inflammatory state termed “trained innate immunity.”