The use of experimental artefacts in African trypanosome research.

When trypanosomes are removed from the field and maintained in laboratory conditions, phenotypic changes commonly occur such that the lines used by many investigators in routine work show several differences from the populations that affect humans and cattle in Africa. Whether these differences are important or irrelevant of course depends on the purpose of each particular experiment, but an awareness of what the differences are can be a useful aid in the interpretation of results. Furthermore, trypanosomes can be manipulated in the laboratory to possess particular characteristics that aid in the testing of hypotheses that are difficult to test using 'wild-type' trypanosomes. In this article, Mike Turner describes how some defined trypanosome lines have been created, how they differ from one another and several of their uses.