Trypanosoma congolense: re-expression of a deleted metacyclic variable antigen type in vivo and in vitro.
The expression of variable antigen types (VATs) was determined among dividing populations of T. congolense growing in vivo in rabbit chancres and in vitro on bovine aorta endothelial cell monolayers. Experiments were performed in which a single metacyclic VAT (M-VAT) was deleted from a cultured metacyclic population by neutralisation with a monoclonal antibody and complement. Subsequent expression of the deleted M-VAT and two unrelated M-VATs was determined by an indirect immunofluorescent antibody test. The deleted M-VAT was re-expressed both in vivo and in vitro and the proportions of unrelated M-VATs were not markedly affected by the neutralisation of this single M-VAT. In addition, an overall similarity was observed between M-VAT expression and re-expression in vivo and in vitro.
Centre for Tropical Veterinary Medicine, Roslin, Midlothian, U.K.
D V
DV
Sutherland
C A
CA
Ross
A G
AG
Luckins
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000940:Antigenic Variation; D000953:Antigens, Protozoan / Q000032:analysis / Q000276:immunology*; D002478:Cells, Cultured; D005455:Fluorescent Antibody Technique; D009500:Neutralization Tests; D014348:Trypanosoma congolense / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000953:Antigens, Protozoan