Immunity in trypanosomiasis. II. Agglutination reaction with African trypanosomes

Abstract

Agglutination reactions between living trypanosomes and sera of experimentally infected rabbits is described.Agglutinins in infected rabbits and in hyperimmunized rabbits with dead trypanosomes appeared between 5 and 8 days and reached their maximum within 14 days. They persisted in infected untreated rabbits until death, but in infected rabbits treated with Suramin they persisted for only 3 months. In hyperimmunized rabbits the titre of agglutinins gradually fell and disappeared 4 weeks after the last inoculation.Agglutinins appear to be species specific; sera of rabbits infected with T. brucei agglutinated homologous and heterologous strains of the T. brucei, but failed to agglutinate heterologous species of trypanosomes. Similar results were obtained with sera of other species of trypanosomes.Four sera from naturally occurring cases of T. rhodesiense infection in man produced agglutination reactions with titre varying from 1:80 to 1:1280 with T. rhodesiense, but did not agglutinate T. brucei.