Coevolution of the coagulation and immune systems.

BACKGROUND: Higher organisms rely on the coagulation and immune systems to fight disease-causing pathogens and other foreign invaders in the body. Coagulation has an important role as a barrier against foreign bodies, including bacteria, viruses, and protozoa. The protective responses associated with the coagulation and immune systems can protect the host organism from a wide range of pathogens, such as viruses, parasites, fungi, and even bacteria.

AIM: The purpose of this paper was to review available research on the evolution of the coagulation and immune systems.

MATERIALS AND METHODS: The study analyzed evidence from studies that have examined the coagulation and immune systems in the context of evolutionary processes. The articles used in the review were identified from the PsycINFO, CIHAHL, PubMed, Web of Science, and CIHAHL databases.

RESULTS: Studies have shown that both the coagulation system and the early immune system originated from the same initial system in early organisms. Some researchers argue that hemocytes from lower organisms are the common link from which the immune system and coagulation system developed.

DISCUSSION AND CONCLUSION: Simple organisms have hemocytes that can carry out both immune response and coagulation processes. Evolution led to the separation of these processes in higher organisms. Furthermore, this divergence resulted in the emergence of thrombocytes and plasmatic coagulation subsystems. These observations explain why there is some form of overlap between immunity and hemostasis, even in advanced organisms such as vertebrates. Several phenomena in clinical medicine related to coagulation and immunity can be explained by this overlap and are consistent with the hypothesis of the coevolution of coagulation and the immune system.