Abstract
It is postulated that helminth infections are able to protect their hosts from immune mediated diseases such as allergies and autoimmune diseases, due to strong parasite-driven immune regulatory processes. The development of helminth-based therapies is very attractive to treat those pathologies. In this chapter, we will be reviewing some epidemiological and experimental evidences whereby helminth infection could protects from immune-mediated diseases, the mechanisms that are behind this phenomenon as well as the main strategies that have been used by research groups to develop biological products for treatment and prophylaxis of these immunopathologies based in mild infection by worms or, more importantly, their molecules.