title: Relationship between Antibody Levels, IgG Binding to Plasmodium falciparum-Infected Erythrocytes, and Disease Outcome in Hospitalized Urban Malaria Patients from Dakar, Sénégal.
abstract: Background. Management of clinical malaria requires the development of reliable diagnostic methods and efficient biomarkers for follow-up of patients. Protection is partly based on IgG responses to parasite antigens exposed at the surface of infected erythrocytes (iRBCs). These IgG responses appeared low during clinical infection, particularly in severe disease. Methods. We analyzed the IgG binding capacity to the surface of live erythrocytes infected by knob positive FCR3 strain. Sera from 69 cerebral malaria (CM) and 72 mild malaria (MM) cases were analyzed by ELISA for IgG responses to five antigens from iRBC and by flow cytometry for IgG binding as expressed in labeling index ratio (LIR). The relationship between IgG levels, LIR, parasitemia, age, and the clinical outcomes was evaluated. Results. We found a significant decrease of LIR in adult CM fatal cases compared to surviving patients (p = 0.019). In MM, LIRs were correlated to IgG anti-iRBC and anti-PfEMP3/5 levels. In CM, no correlation was found between LIR, IgG levels, and parasitemia. Conclusion. The IgG binding assay was able to discriminate outcome of cerebral malaria cases and it deserves further development as a potential functional-associated assay for symptomatic malaria analysis.
authors: Service d'Immunologie FMPO, Université Cheikh Anta Diop de Dakar, Dakar, Senegal; Unité d'Immunogénétique, Institut Pasteur de Dakar, Dakar, Senegal.
authors: Babacar
authors: B
authors: Mbengue
authors: Service de Réanimation, Hôpital Principal de Dakar, Dakar, Senegal.
authors: Mouhamadou Mansour
authors: MM
authors: Fall
authors: Service d'Immunologie FMPO, Université Cheikh Anta Diop de Dakar, Dakar, Senegal.
authors: Maguette
authors: M
authors: Sylla Niang
authors: Service de Réanimation, Hôpital Principal de Dakar, Dakar, Senegal.
authors: Birahim
authors: B
authors: Niang
authors: Unité d'Immunologie, Institut Pasteur de Dakar, Dakar, Senegal.
authors: Marie Louise
authors: ML
authors: Varela
authors: Unité d'Immunogénétique, Institut Pasteur de Dakar, Dakar, Senegal.
authors: Antoine Marie
authors: AM
authors: Diatta
authors: Service d'Immunologie FMPO, Université Cheikh Anta Diop de Dakar, Dakar, Senegal.
authors: Moustapha
authors: M
authors: Mbow
authors: Service d'Immunologie FMPO, Université Cheikh Anta Diop de Dakar, Dakar, Senegal.
authors: Kantome
authors: K
authors: Ndiaye
authors: Unité d'Immunogénétique, Institut Pasteur de Dakar, Dakar, Senegal.
authors: Rokhaya
authors: R
authors: Ndiaye Diallo
authors: Service d'Immunologie FMPO, Université Cheikh Anta Diop de Dakar, Dakar, Senegal; Unité d'Immunogénétique, Institut Pasteur de Dakar, Dakar, Senegal.
authors: Alioune
authors: A
authors: Dieye
authors: Unité d'Immunologie, Institut Pasteur de Dakar, Dakar, Senegal.
authors: Ronald
authors: R
authors: Perraut
mesh_terms: D000913:Antibodies, Protozoan / Q000097:blood / Q000276:immunology*; D004912:Erythrocytes / Q000276:immunology* / Q000378:metabolism / Q000469:parasitology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D016779:Malaria, Cerebral / Q000097:blood / Q000453:epidemiology / Q000276:immunology*; D016778:Malaria, Falciparum / Q000097:blood / Q000453:epidemiology / Q000276:immunology*; D008297:Male; D010963:Plasmodium falciparum / Q000276:immunology* / Q000378:metabolism; D012675:Senegal / Q000453:epidemiology
chemical_list: D000913:Antibodies, Protozoan; D007074:Immunoglobulin G