title: Selective pressure can influence the resistance of Trypanosoma congolense to normal human serum.
abstract: Resistance and sensitivity to normal human serum (NHS) of Trypanosoma congolense, a parasite believed to cause disease in animals only, were investigated in vivo as well as in vitro. Our results indicate that like Trypanosoma brucei, T. congolense can be grouped into three different phenotypes according to its resistance to NHS. Some strains are completely resistant to NHS, like Trypanosoma brucei gambiense and the resistant form of Trypanosoma brucei rhodesiense. Other strains show a very low degree of resistance comparable to the sensitive form of T. b. rhodesiense, and some are completely sensitive to NHS. Continuous passaging in mice in the presence or absence of NHS shows that the resistance and sensitivity of T. congolense can be reversed like in T. b. rhodesiense. Our data suggest that T. congolense might be able to infect man in regions where animals may serve as reservoirs for the infection.
authors.affiliation: Department of Immunology, Parasitology and Ultrastructure, Flanders Interuniversity for Biotechnology, 65 Paardenstraat, B 1640, St. Genesius Rode, Belgium. xong@dbm.ulb.ac.be
authors.forename: Hoang Van
authors.initials: HV
authors.lastname: Xong
authors.forename: Patrick
authors.initials: P
authors.lastname: De Baetselier
authors.forename: Etienne
authors.initials: E
authors.lastname: Pays
authors.forename: Stefan
authors.initials: S
authors.lastname: Magez
mesh_terms: D000818:Animals; D001790:Blood Physiological Phenomena; D005260:Female; D006801:Humans; D051379:Mice; D018512:Parasitemia / Q000276:immunology / Q000469:parasitology; D010641:Phenotype; D012692:Serial Passage; D014348:Trypanosoma congolense / Q000145:classification / Q000276:immunology* / Q000472:pathogenicity; D014353:Trypanosomiasis, African / Q000276:immunology* / Q000469:parasitology