The Istar 1 Serodeme of Trypanosoma brucei: Development of a New Serodeme

Abstract

An extensive serodeme of sequentially-isolated antigenic variants of African trypanosomes has been produced from both syringe-passaged and cyclically-transmitted Trypanosoma brucei of the IsTaR 1 clone derived from EATRO 164. The majority of the antigenic variants were isolated from chronically-infected deer mice (Peromyscus leucopus). The pattern of parasitemias during the course of infections initiated with syringe-passaged trypanosomes differed from those initiated with cyclically-transmitted trypanosomes. Trypanosome populations from syringe-passaged (192) and cyclically-transmitted (31) clones were each amplified by growth in lethally-irradiated mice and cryopreserved for retrospective analysis. Five clones derived from a single deer mouse during the first 44 days of infection, and 2 clones derived from an acutely-infected rat were established from these amplified populations. Homogeneous populations were grown in lethally-irradiated rats and mice for antigenic analysis purification of variant-specific glycoprotein. Six of the 7 clones were distinct variants by immunological criteria using antisera derived from whole cells or purified surface glycoproteins. Two clones, one derived from the acutely-infected rat, and the other from the first parasitemia in a chronic infection that was initiated with the former clone, were immunologically identical. Production of these clones established a well-defined serodeme that will allow detailed analysis of antigenic variation.

The trypanosome spliced leader small RNA gene family: stage-specific modification of one of several similar dispersed genes

“…Antigenically homogeneous bloodstream stage trypanosomes of various variant antigen types (VATs) of the IsTaR serodeme of Trypanosoma brucei brucei were grown and isolated as described (17,18). Procyclic stage trypanosomes were propagated in vitro (14).…”

“…As described in this report, we have cloned and analyzed in detail one of the SL orphons from the IsTaR serodeme of T. brucei (17). Comparison of this orphon with the other IsTaR SL orphons indicates that, unlike orphons of other gene families, three of the four SL orphons are embedded in similar regions of genomic DNA.…”

Creation of AUG initiation codons by addition of uridines within cytochrome b transcripts of kinetoplastids.

“…Clones of L. tarentolae (University of California strain) and C. fasciculata (Cf-cl) were grown in brain heart infusion medium supplemented with 10-20 ,g of, hemin per ml, as described (20). Clone IsTaR 1 of T. b. brucei (stock EATRO 164) was grown in procyclic culture as described (21). Cells of all three species were harvested at late logarithmic or stationary phase and either were used immediately or were frozen in liquid nitrogen and stored at -80°C.…”

Trypanosoma brucei gBP21

“…The protein was enriched from low salt detergent extracts of T. brucei mitochondria isolated from the procyclic life cycle stage of strain IsTaR 1 (19). As an assay system for the enrichment we used the demonstrated ability of the polypeptide to specifically bind to gRNA molecules, which was monitored in an UV light induced label transfer experiment as described in Ref.…”

“…Isolation-The procyclic life cycle stage of T. brucei brucei strain IsTaR 1 (19) was grown in SDM-79 as described (20). Bloodstream trypanosomes (clone MITat 1.2) were grown in HMI-9 medium according to Ref.…”