What role does the immune system play in aging? How do senescent cells evade it and promote inflammation? And what does it reveal about developing effective interventions? Immunologist Arne Akbar joins Gordon to break down the array of actors and pathways involved, including sestrins, immune memory, the gut microbiome, and more. Along the way, Arne highlights the need to connect across research areas, and shares why courage is the most important quality for a scientist to cultivate.