Final answer:
The cardiovascular system, specifically via its network of capillaries, is responsible for the release of nutrients, immune factors, and oxygen to the tissues within the interstitial spaces.
Step-by-step explanation:
The structure that is located in the interstitial spaces within tissues and releases nutrients, immune factors, and oxygen to those tissues is the cardiovascular system. The capillaries of the cardiovascular system are specifically the sites where such exchanges take place. These small vessels are situated within the interstitial spaces, and they allow for the diffusion of oxygen and nutrients from the blood into the surrounding tissue, while also enabling the removal of carbon dioxide and metabolic waste back into the bloodstream for elimination.
The lymphatic system, on the other hand, plays an essential role in transporting excess interstitial fluid back to the bloodstream and in the immune response by circulating lymphocytes. However, it is not directly involved in the exchange of nutrients, oxygen, and immune factors in the way that the cardiovascular system's capillaries are.