Evidence for multiple B- and T-cell epitopes in Plasmodium falciparum liver-stage antigen 3.

Liver-stage antigen 3 (LSA-3) is a new vaccine candidate that can induce protection against Plasmodium falciparum sporozoite challenge. Using a series of long synthetic peptides (LSP) encompassing most of the 210-kDa LSA-3 protein, a study of the antigenicity of this protein was carried out in 203 inhabitants from the villages of Dielmo (n = 143) and Ndiop (n = 60) in Senegal (the level of malaria transmission differs in these two villages). Lymphocyte responses to each individual LSA-3 peptide were recorded, some at high prevalences (up to 43%).

Anti-NANP antibody and treatment efficacy in patients with acute uncomplicated falciparum malaria attacks.

African patients originating from the hypoendemic, urban area of Greater Dakar (Senegal, West Africa) who presented with an acute Plasmodium falciparum infection were studied using an in-vivo chloroquine sensitivity assay for 28 days. Forty-seven patients with acute malaria infections were treated with 25 mg/body weight of chloroquine. Adequate responses to treatment were observed in 24 patients (51%), whereas 23 (49%) were resistant.

Apoptosis modulation in mononuclear cells recovered from individuals exposed to Plasmodium falciparum infection.

In endemic areas, asymptomatic infection by the malaria parasite Plasmodium falciparum was found associated with elevated percentages of human host's mononuclear cell spontaneous in-vitro apoptosis. In Dielmo, a village where malaria is holoendemic, apoptosis was age-and parasite-dependent. In-vitro exposure of peripheral blood mononuclear cells (PBMC) to the parasite extract induced a marked increase in the mononuclear cell membrane expression of functional CD95 antigen: a 3-h exposure of the mononuclear cells to anti-CD95 antibodies led to a detectable increase in the mean percentage of apoptotic nuclei found in the cultures carried out in the presence of P.

Reduced immune activation and T cell apoptosis in human immunodeficiency virus type 2 compared with type 1: correlation of T cell apoptosis with beta2 microglobulin concentration and disease evolution.

This study analyzes the degree of immune activation and characterizes apoptosis in lymphocytes from healthy West African donors or patients infected with human immunodeficiency virus (HIV)-1 or -2. The lower decline of CD4 T cells in HIV-2- compared with HIV-1-infected donors is associated with lower levels of immune activation, evaluated by HLA-DR expression on lymphocytes and sera concentrations of IgG and beta2 microglobulin (beta2m). Ex vivo apoptosis was found in both infections in all lymphocyte subsets, including CD4 and CD8 T cells, as well as B cells, but was lower in HIV-2 than in HIV-1 infection.

Prognostic value of anti-Plasmodium falciparum-specific immunoglobulin G3, cytokines, and their soluble receptors in West African patients with severe malaria.

Forty-one African patients suffering from clinically defined severe malaria were studied in the intensive medical care unit of the main hospital in Dakar, Senegal, West Africa. All of these individuals lived in Greater Dakar, an area of low and seasonal Plasmodium falciparum endemicity. Twenty-seven patients (mean age +/- 1 standard deviation, 19.