SciELO - Scientific Electronic Library Online

 
vol.87 suppl.5Coevolution of hosts and microorganisms: an analysis of the involvment of cytokines in host-parasite interactions author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Journal

Article

Indicators

Related links

Share


Memórias do Instituto Oswaldo Cruz

Print version ISSN 0074-0276On-line version ISSN 1678-8060

Mem. Inst. Oswaldo Cruz vol.87  suppl.5 Rio de Janeiro  1992

http://dx.doi.org/10.1590/S0074-02761992000900001 

Vaccine strategies against schistosomiasis

A. Capron1 

J. P. Dessaint1 

M. Capron1 

R. J. Pierce1 

Institut Pasteur, CNRS 624, Unité Mixte INSERM U167. Centre d'Immunologie et de Biologie Parasitaire, Lille, France

ABSTRACT

Schistosomiasis, the second major parasitic disease in the world after malaria affects at least 200 million people, 500 million being exposed to the risk of infection. It is widely agreed that a vaccine strategy wich could lead to the induction of effector mechanisms reducing the level of reinfection and ideally parasite fecundity would deeply affect the incidence of pathological manifestations as well as the parasite transmission potentialities. Extensive studies performed in the rat model have allowed the identification of novel effector mechanisms involving IgE antibodies and various inflammatory cell populations (eosinophils, macrophages and platelets) whereas regulation of immune response by blocking antibodies has been evidencial. Recent epidemiological studies have now entirely confirmed in human populations the the role of IgE antibodies in the acquisition of resistance and the association of IgG4 blocking antibodies with increased susceptibility. On the basis of these concepts, several schistosome glutathion S-transferase (Sm 28 GST) appears as a pronising vaccine candidate. Immunization experiments have shown that two complementary goals can be achieved: (a) a partial but significant reduction of the worm population (up to 60//in rats); (b) a significant reduction of parasite fecundity (up in the mice and 85//in cattle) and egg viability (up to 80//). At least two distinct immunological mechanisms account for these two effects. IgE antibodies appear as a major humoral component of acquired resistance whereas IgA antibodies appear as a major humoral factor affecting parasite fecundity. These studies seem to represent a parasite diseases through the identification of potentially protective antigens and of the components of the immune response which vaccination should aim at inducing.

Key words: schistosomiasis; vaccine; IgE; IgA; protection

 

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License