Unravelling human trypanotolerance: IL8 is associated with infection control whereas IL10 and TNFα are associated with subsequent disease development.
In West Africa, Trypanosoma brucei gambiense, causing human African trypanosomiasis (HAT), is associated with a great diversity of infection outcomes. In addition to patients who can be diagnosed in the early hemolymphatic phase (stage 1) or meningoencephalitic phase (stage 2), a number of individuals can mount long-lasting specific serological responses while the results of microscopic investigations are negative (SERO TL+). Evidence is now increasing to indicate that these are asymptomatic subjects with low-grade parasitemia. The goal of our study was to investigate the type of immune response occurring in these "trypanotolerant" subjects. Cytokines levels were measured in healthy endemic controls (n = 40), stage 1 (n = 10), early stage 2 (n = 19), and late stage 2 patients (n = 23) and in a cohort of SERO TL+ individuals (n = 60) who were followed up for two years to assess the evolution of their parasitological and serological status. In contrast to HAT patients which T-cell responses appeared to be activated with increased levels of IL2, IL4, and IL10, SERO TL+ exhibited high levels of proinflammatory cytokines (IL6, IL8 and TNFα) and an almost absence of IL12p70. In SERO TL+, high levels of IL10 and low levels of TNFα were associated with an increased risk of developing HAT whereas high levels of IL8 predicted that serology would become negative. Further studies using high throughput technologies, hopefully will provide a more detailed view of the critical molecules or pathways underlying the trypanotolerant phenotype.
Centre International de Recherche-Développement sur l'Elevage en zones Subhumides (CIRDES), Unité de Recherches sur les Bases Biologiques de la Lutte Intégrée, Bobo-Dioulasso, Burkina Faso.
Hamidou
H
Ilboudo
Institut de Recherche pour le Développement (IRD), UMR IRD-CIRAD 177 INTERTRYP, Campus International de Baillarguet, Montpellier, France.
Rachel
R
Bras-Gonçalves
Ministère de la Santé et de l'Hygiène Publique, Programme National de Lutte contre la Trypanosomose Humaine Africaine, Conakry, Guinée.
Mamadou
M
Camara
Centre de coopération Internationale en Recherche Agronomique pour le développement (CIRAD), UMR IRD-CIRAD 177 INTERTRYP, Campus International de Baillarguet, Montpellier, France; Institut National de la Recherche Agronomique (INRA), UMR 1313 GABI, F78350 Jouy-en-Josas, France.
Laurence
L
Flori
Ministère de la Santé et de l'Hygiène Publique, Programme National de Lutte contre la Trypanosomose Humaine Africaine, Conakry, Guinée.
Oumou
O
Camara
Centre International de Recherche-Développement sur l'Elevage en zones Subhumides (CIRDES), Unité de Recherches sur les Bases Biologiques de la Lutte Intégrée, Bobo-Dioulasso, Burkina Faso.
Hassane
H
Sakande
Ministère de la Santé et de l'Hygiène Publique, Programme National de Lutte contre la Trypanosomose Humaine Africaine, Conakry, Guinée.
Mamadou
M
Leno
Institut de Recherche pour le Développement (IRD), UMR IRD-CIRAD 177 INTERTRYP, Campus International de Baillarguet, Montpellier, France.
Elodie
E
Petitdidier
Centre International de Recherche-Développement sur l'Elevage en zones Subhumides (CIRDES), Unité de Recherches sur les Bases Biologiques de la Lutte Intégrée, Bobo-Dioulasso, Burkina Faso; Institut de Recherche pour le Développement (IRD), UMR IRD-CIRAD 177 INTERTRYP, Campus International de Baillarguet, Montpellier, France.
Vincent
V
Jamonneau
Institut de Recherche pour le Développement (IRD), UMR IRD-CIRAD 177 INTERTRYP, Campus International de Baillarguet, Montpellier, France; Ministère de la Santé et de l'Hygiène Publique, Programme National de Lutte contre la Trypanosomose Humaine Africaine, Conakry, Guinée.
Bruno
B
Bucheton
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007113:Immunity, Innate; D016753:Interleukin-10 / Q000097:blood / Q000276:immunology*; D016209:Interleukin-8 / Q000097:blood / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D014347:Trypanosoma brucei gambiense / Q000276:immunology* / Q000378:metabolism; D014353:Trypanosomiasis, African / Q000097:blood / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood / Q000276:immunology*
C508606:CXCL8 protein, human; C508609:IL10 protein, human; D016209:Interleukin-8; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10