Rational design of nematode vaccines; natural antigens.

Bacterial and viral vaccines have been used for several decades and have made an invaluable impact on the control of both human and animal diseases. As these vaccines are based on the induction of the "natural" protective immune response of the host, there is ample proof that this approach is effective and there is no a priori reason why a similar approach should not work for other infectious organisms, including helminth parasites. Two main stumbling blocks have so far precluded the development of effective anti-nematode vaccines: (i) the identification and isolation of the protective parasite antigens; and (ii) the induction of the appropriate protective immune effector mechanisms through vaccination. This paper will discuss the unique characteristics of nematode vaccine development and the significant progress that has been made in recent years in this area.