Trypanosoma brucei: Analysis of relapsing populations in sensitive and resistant breeds of cattle

• Published in: Experimental parasitology Vol. 60; no. 1; pp. 18 - 31
• Main Authors: Roelants, G.E., Duvallet, G., Hirsch, W., Kanwe, B., Pinder, M., Guidot, G., Libeau, G., Van Melick, A.
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01.08.1985; Elsevier
• Subjects: Agglutination Tests; Animals; Antibody Formation; ANTIGENE; ANTIGENOS; ANTIGENS; Antigens, Protozoan - analysis; Antigens, Protozoan - immunology; Biological and medical sciences; BREEDS; CATTLE; CEBU; Clone Cells; Experimental protozoal diseases and models; Fluorescent Antibody Technique; GANADO BOVINO; GLICOPROTEINAS; GLYCOPROTEINE; GLYCOPROTEINS; Glycoproteins - analysis; GROS BETAIL; Human protozoal diseases; Immunity, Innate; Infectious diseases; Medical sciences; Mice; Molecular Weight; Parasitic diseases; PEST RESISTANCE; Protozoal diseases; RACE; RAZAS; RESISTANCE AUX RAVAGEURS; RESISTENCIA A LAS PLAGAS; Tropical medicine; TRYPANOSOMA; TRYPANOSOMA BRUCEI; Trypanosoma brucei brucei - classification; Trypanosoma brucei brucei - immunology; Trypanosoma brucei brucei - pathogenicity; Trypanosomiasis; Trypanosomiasis, Bovine - immunology; Trypanosomiasis, Bovine - parasitology; variable antigen type; Variant Surface Glycoproteins, Trypanosoma; VIRULENCE; VIRULENCIA; ZEBU; ZEBU CATTLE; Glycoprotein isolation; Blood inhibition infectivity test; Human serum; Cattle, bovid; Rabbit; Variant specific glycoprotein; Hemoflagellate; Variable antigen type; Concanavalin A; Trypanosoma brucei brucei; Molecular weight; Mouse; Isoelectric point; N-cbz- l-phenylalaninechloromethylketone; p I; Trypanotolerance; Protozoa, parasitic; Octyl-β- d-glucopyranoside; African trypanosomiasis; Bovine; Pathogenesis; Virulence; Glycoproteins; Parasitosis; Experimental animal; Cell surface; Infection; Variant; Experimental disease; Parasitemia; Trypanosoma brucei; Clone
• ISSN: 0014-4894; 1090-2449
• DOI: 10.1016/S0014-4894(85)80019-9

The clone DiTat 1.1 of Trypanosoma brucei brucei was injected into four bovids, and clones obtained from successive waves of parasitemia were used to study the expressed variant-specific surface glycoprotein repertoire. Twenty-four clones were obtained which could be classified into 12 different variable antigen types, in addition to the clone injected, using agglutination or immunofluorescence with monospecific antisera. The variable surface glycoproteins of the 25 clones were extracted using the detergent octyl-β- d-glucopyranoside in the presence of the protease inhibitor, N-cbz- l-phenylalaninechloromethylketone. The molecular weights varied from 52,000 to 69,000 and the p I from 5.0 to 8.8. The virulence of 14 clones representing 13 variable antigen types was ascertained in mice. The mean survival time ranged from 20.5 to 43.0 days. Clones isolated from early peaks of parasitemia in the bovid were the most virulent while clones derived from later peaks were less virulent. It seems that organisms of diminishing virulence appear in bovids, leading to self-cure of the disease. All clones were sensitive to human serum in a blood infectivity inhibition test. Antibody against all virulent clones appeared in 20 cattle (10 Zebus, 10 Baoulés) which had been injected with T. brucei DiTat 1.1. There was no evidence for parasites of high or low virulence being preferentially expressed in resistant or sensitive hosts.