Comparison of the unique characteristics of the immune system in different species of mammals.

The current interpretation of how cytokines regulate immune responses is based largely on studies conducted in humans and rodents. As summarized here, comparative studies have revealed significant differences in the composition of the immune system in other species. The difference noted emphasize that it will not be possible to fully understand the role of cytokines in immune regulation without comparative studies that include analysis of cytokine function in additional species.