The work presented in this thesis aimed at increasing our understanding of the effect of helminths on Plasmodium spp. immune response in co-infected individuals living in endemic countries. It... Show moreThe work presented in this thesis aimed at increasing our understanding of the effect of helminths on Plasmodium spp. immune response in co-infected individuals living in endemic countries. It presents data from studies conducted in rural and semi urban areas of Lambaréné (Gabon) where the burden of malaria and helminths is particularly important. Although scarce previous studies have indicated an effect of helminths on malaria outcomes and immune response to Plasmodium spp. parasite in co-infected subjects. However it is still debated how consistent is this effect across study sites and teams and what its immunological basis is. Show less
Early childhood is a critical period where the maturation of the immune system occurs while it receives various challenges from the environment shared with the mother. Children growing in an... Show moreEarly childhood is a critical period where the maturation of the immune system occurs while it receives various challenges from the environment shared with the mother. Children growing in an environment rich in micro-organisms and parasites are thought to have a different pattern of immune response compared to those children growing in a more hygienic environment. This difference might contribute to the lower prevalence of allergic and autoimmune disorders in developing countries compared to affluent countries. Within this context, a number of cohort studies mostly performed in developed countries have focused on finding the link between the pattern of immune responses in early life and health outcomes in later life. In this thesis, we studied child__s innate and adaptive responses during the first 4 years of life in a helminth-endemic area in Indonesia Show less
The studies present in this thesis fall into two broad areas: the first focusing on filarial infection, Ig (immunoglobulin)E levels and risk factors for infection, while the second deals with the... Show moreThe studies present in this thesis fall into two broad areas: the first focusing on filarial infection, Ig (immunoglobulin)E levels and risk factors for infection, while the second deals with the possible associations between nematode infection and allergy. Compared to ELISA, RAST is superior in detecting filarial specific IgE in endemic area of Brugia malayi. Levels of filaria-specific IgE and IgG4 in children up to 10 years correlated with maternal antibody levels. Genetic factors had a more pronounced effect in children than in adults. The use of objective measurements, such as skin prick test (SPT) and IgE levels are required when conducting epidemiological studies of allergic diseases in Indonesia. Study on risk factors of allergy in Indonesia showed that nutritional status of children in the high socioeconomic school negatively associate with SPT and IgE positivity but we did not show a statistically significant role for helminths in inhibiting SPT responses. In endemic area of lymphatic filariasis, genetic factors contribute significantly to both total and allergen-specific IgE, whereas environmental factors influence the clustering of SPT positivity. By using several TLR ligands it was demonstrated that the dynamics of cytokine production following the innate immune stimulation can differ according to helminth infection status. Show less
