Specific immune responses and mechanisms in malaria exposed Gabonese

Many efforts are devoted for the control of malaria, particularly in sub-Saharan Africa. Antigen diversity including allelic polymorphism and antigenic variation, the lack of good animal models for malaria, and the lack of surrogate markers of protection are some of the obstacles for effective drugs and vaccines development. In the present thesis specific humoral immune responses and mechanisms that occur in populations exposed to malarial infection was evaluated. First, IgG antibodies were assessed against GLURP among people with asymptomatic malarial infection. The second study focussed on the identification of factors involved in the activation of antibody production against a P. falciparum antigen. The third part of the work was devoted to the investigation of the presence of endothelium damaged factors in plasma samples from P. falciparum infected patients and their implications. The results showed: 1)- a significant lower level of IgG4 in hemoglobin AS children, 2)- a significant correlation between IgG1 and IL21 levels, 3)- a positive correlation between levels of both sE-Selectin, TM and clinical, biological and immunological factors.