One of the most important discoveries about Somatomedin C in the last 30 years comes from the work of Dr. Arthur Johnson of the University of Minnesota in Duluth. Dr. Johnson discovered that Somatomedin C contains a small molecular weight protein which has the unique ability to modulate the immune system. This means that, if the immune system is depressed, this particular protein can dramatically improve it. And, if the immune system is overactive, it can reduce its activity until it reaches the normal range. Somatomedin C has been shown to be capable of modulating the immune system.