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Vaccines against blood-feeding nematodes of humans and livestock

Published online by Cambridge University Press:  02 February 2007

J. M. BETHONY ,
A. LOUKAS ,
P. J. HOTEZ  and
D. P. KNOX
J. M. BETHONY
Affiliation:
Centro de Pesquisas René Rachou/CPqRR, A FIOCRUZ em Minas Gerais. Rene Rachou Research Center/CPqRR, The Oswaldo Cruz Foundation in the State of Minas Gerais, Brazil
A. LOUKAS
Affiliation:
Helminth Biology Laboratory, Division of Infectious Diseases and Immunology Queensland Institute of Medical Research, 300 Herston Rd, Herston, QLD 4006 Australia
P. J. HOTEZ
Affiliation:
Centro de Pesquisas René Rachou/CPqRR, A FIOCRUZ em Minas Gerais. Rene Rachou Research Center/CPqRR, The Oswaldo Cruz Foundation in the State of Minas Gerais, Brazil Dept. of Microbiology and Tropical Medicine, The George Washington University, Ross Hall, Room 736, 2300 Eye St. NW, Washington DC 20037
D. P. KNOX
Affiliation:
Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian, UK, EH26 0PZ
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Abstract

This paper summarises the progress towards vaccine development against the major blood-feeding nematodes of man and livestock, the hookworms and Haemonchus contortus, respectively. The impact of the diseases and the drivers for vaccine development are summarized as well as the anticipated impact of the host immune response on vaccine design. The performance requirements are discussed and progress towards these objectives using defined larval and adult antigens, many of these being shared between species. Specific examples include the Ancylostoma secreted proteins and homologues in Haemonchus as well as proteases used for digestion of the blood meal. This discussion shows that many of the major vaccine candidates are shared between these blood-feeding species, not only those from the blood-feeding stages but also those expressed by infective L3s in the early stages of infection. Challenges for the future include: exploiting the expanding genome information for antigen discovery, use of different recombinant protein expression systems, formulation with new adjuvants, and novel methods of field testing vaccine efficacy.

Keywords

HookwormsAncylostomaHaemonchusvaccineproteasesASPs
Type
Research Article
Information
Parasitology , Volume 133 , Supplement S2: Parasite Vaccines , October 2006 , pp. S63 - S79
Copyright
© 2006 Cambridge University Press

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