The neuroimmunoendocrine network during worm helminth infections

Abstract

The physiological interactions during the course of the immune response to helminthes are
complex. As our understanding of the neuroendocrine system grows, it has become increasingly clear that this complex network of neurotransmitters, hormones, and cytokines plays an important role in mediating immunity, in general, but in the case of helminthes this interaction among different systems is crucial. Helminthes present a complex relationship in the host’s physiological systems, with neuro and hormonally dependent host factors such as sex, age, and the host physiological status correlated with parasite success. On top of the effect that this particular type of parasites may have on the invaded host, recent experimental evidence suggest that helminth parasites not only actively evade immune response, but are also able to exploit the hormonal microenvironment within their host to favor their establishment, growth and reproduction. The close interaction of the worm with the host’s homeostatic systems, the molecules produced by them, and the activation of immune mediated mechanisms to eliminate it, activate a complex neuroendocrine network, that produces strong behavioral changes in the infected host. Understanding how the host’s neuroendocrine system can under certain circumstances favor the establishment of a parasitic infection opens interesting perspectives into the host parasite relationship field. This review focuses on the host-parasite neuroendocrine network activated by parasite worm infections.