0.00/10 2001-02-04 30 minutes.HDWhy some people have allergic reactions, and others don't. How your immune system works - or doesn't work is discussed. A look at auto-immune disease is discovered. The team focuses on the structure and function of living systems, the immune system, including auto-immune response, and regulation and behaviour of living systems.An: 2001Studio: TVOntarioPays: Canada, United States of America