After obtaining consent from parents, blood was from each child and plasma stored at -20C until use

After obtaining consent from parents, blood was from each child and plasma stored at -20C until use. different laboratories. Results The incidence rate of malaria was 0.35 episodes per child per year. Isotype and IgG subclasses for those antigens investigated improved with age, while the risk of malaria decreased with age. After modifying for age, Remodelin higher levels of IgG to GLURP, MSP119, MSP3 and IgM to MSP119, MSP3 and AMA1 were associated with decreased Remodelin Remodelin malaria incidence. Of the IgG subclasses, only IgG1 to MSP119 was associated with reduced incidence of medical malaria. A earlier study in the same location failed to find an association of antibodies to MSP119 with medical malaria. The disagreement may be due to variations in reagents, ELISA and analytical methods used in the two studies. When IgG, IgM and IgG subclass levels for all four antigens were included in a combined model, only IgG1 [(0.80 (0.67C0.97), p = 0.018)] and IgM [(0.48 (0.32C0.72), p 0.001)] to MSP119 were independently associated with safety from malaria. Summary Using standardized methods, the study offers confirmed the importance of antibodies to MSP119 in reducing the risk of medical malaria in Ghanaian children, therefore substantiating its potential like a malaria vaccine candidate. Background Malaria remains probably one of the most important causes of morbidity and mortality in the world. Current methods of control are only partially effective and, therefore, the development of a vaccine which can provide a high degree of safety is a priority. Antibody-mediated immune reactions to malaria antigens are known to be involved in protecting against disease [1-4], but the antigens that induce protecting antibodies have not been conclusively recognized. Immuno-epidemiological studies from different laboratories have sometimes yielded conflicting results [5-8]. This may be partly due to variations in malaria endemicity and the use of different study designs, reagents, assay protocols and statistical methodologies. In an attempt to make such studies more similar, the Afro-Immuno Assay (AIA) network project was Rabbit Polyclonal to OR8J3 initiated. The network includes six African Organizations in Gabon, Ghana, Burkina Faso, Senegal, Tanzania, and Zimbabwe and three Western Organizations from Denmark, The Netherlands and France. The Afro-Immuno Assay network has developed standardized enzyme immuno assays [9-11] that guarantee the use of the same reagents, protocols and statistical methods to assess the association between acquisition of malaria specific antibody reactions to four potential malaria vaccine candidate antigens and possible safety from medical malaria. Samples for the AIA multi-center project were retrospectively from cohort studies in six different geographical and epidemiological settings, comprising low endemic to holoendemic areas. These antigens include the Glutamate High Protein (GLURP), the Merozoite Surface Protein 3 (MSP3) [12], the 19-kilo Dalton region of the Merozoite Surface Protein 1 (MSP119) [13] and the Apical Membrane Antigen 1 (AMA1) [14], which are all thought to induce protecting antibody reactions through various mechanisms [15-18]. Vaccines incorporating these antigens are currently in medical tests and are explained in detail elsewhere [7,19-26]. It is likely that a long term malaria vaccine will comprise multiple rather than solitary Remodelin antigens and it is, therefore, useful to study natural immune reactions to multiple malaria antigens in relation to incidence of malaria in a more standardized way. In this study, the standardized AIA ELISA methods [9-11], were used to assess the relationship between incidence of medical malaria and naturally acquired isotype and IgG subclass reactions to these four leading malaria vaccine candidate antigens, AMA1, MSP119, MSP3 and GLURP in Ghanaian children from three to 10 years of age. Materials and methods Study area, study human population and morbidity monitoring Samples used in this study were acquired in March 2002 from a longitudinal study carried out in Dodowa, in which 352 children aged three to 10 years (in the active phase of acquiring immunity to malaria), were enrolled in a study, whose unique goal had been to assess the part of cytokine rules and immunity to malaria. Dodowa is definitely a semi-rural town in the Dangme Western District of the Greater Accra Region of Ghana, about 50 km from the capital Accra and is an.