title: Attenuation of Trypanosoma brucei is associated with reduced immunosuppression and concomitant production of Th2 lymphokines.
abstract: Mechanisms regulating resistance to African trypanosomes were addressed by comparing the immune responses of mice infected with attenuated Trypanosoma brucei brucei lacking the phospholipase C gene (PLC-/-) and those of mice infected with wild-type (WT) parasites. Inhibition of concanavalin A (ConA)-induced T cell proliferation occurred in spleen and lymph nodes of PLC-/-- and WT-infected mice. Although suppressive cells were elicited in spleen and lymph nodes of WT-infected animals, such cells were not detected in lymph nodes of PLC-/--infected mice. PLC-/--infected mice had more interleukin-4 and -10 in their blood than did WT-infected mice. Correspondingly, PLC-/--infected mice had higher IgG1 antibody levels against variant surface glycoprotein than did WT-infected mice. These data indicate that attenuation of T. b. brucei correlates with the absence of cells suppressing ConA-induced T cell proliferation in the lymph nodes, with increased production of Th2 cytokines and a stronger IgG1 antibody response to trypanosome antigens.
authors.affiliation: Department of Immunology, Parasitology, and Ultrastructure, Flemish Interuniversity Institute for Biotechnology, St.-Genesius-Rode, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Namangala
authors.forename: P
authors.initials: P
authors.lastname: de Baetselier
authors.forename: L
authors.initials: L
authors.lastname: Brijs
authors.forename: B
authors.initials: B
authors.lastname: Stijlemans
authors.forename: W
authors.initials: W
authors.lastname: Noël
authors.forename: E
authors.initials: E
authors.lastname: Pays
authors.forename: M
authors.initials: M
authors.lastname: Carrington
authors.forename: A
authors.initials: A
authors.lastname: Beschin
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000096:biosynthesis; D016207:Cytokines / Q000096:biosynthesis*; D005260:Female; D007108:Immune Tolerance; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D016513:Mice, SCID; D018512:Parasitemia / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology*; D014353:Trypanosomiasis, African / Q000276:immunology*; D010738:Type C Phospholipases / Q000502:physiology
chemical_list: D000913:Antibodies, Protozoan; D016207:Cytokines; D010738:Type C Phospholipases