Antigenic variation in Trypanosoma vivax: isolation of a serodeme.

Studies of antigenic variation in Trypanosoma vivax have been hindered by its low infectivity to laboratory hosts and difficulties in obtaining defined cloned populations. The recent isolation of mouse-infective T. vivax has partially overcome the first problem. We have developed a highly efficient cloning technique which has been applied to the isolation of a collection of 71 clones, representing 31 distinct variable antigen types, of mouse-infective T. vivax from Nigeria. This serodeme showed no cross-reaction with several T. brucei-group serodemes, but some cross-reaction with naturally occurring Kenyan T. vivax.