Anti-Trypanosoma brucei activity in Cape buffalo serum during the cryptic phase of parasitemia is mediated by antibodies.

Cape buffalo are reservoir hosts of African trypanosomes. They rapidly suppress population growth of the highly antigenically variable extracellular haemoprotozoa and subsequently maintain a cryptic infection. Here we use in vitro cultures of trypanosomes cloned from Cape buffalo blood during cryptic infection, as well as related and unrelated trypanosomes, to identify anti-trypanosome components present in cryptic-phase infection serum.

Characterisation of the QM gene of Trypanosoma brucei.

The QM protein has been reported to have roles in both tumour suppression and transcription factor regulation in vertebrate cells, and in ribosome stability in both yeast and mammals. The present study isolated the QM gene of Trypanosoma brucei and determined its sequence. Alignment with QM sequences from Saccharomyces cerevisiae, Arabidopsis thaliana, Drosophila melanogaster and Homo sapiens revealed greater than 60% identity.

The African trypanosome cyclophilin A homologue contains unusual conserved central and N-terminal domains and is developmentally regulated.

We have cloned and characterized the homologue of cyclophilin A (CypA) from Trypanosoma brucei brucei, Trypanosoma congolense, Trypanosoma evansi and Trypanosoma vivax. The 1-kilobase African trypanosome CypA complementary DNA contains an open reading frame of 531 base pairs, corresponding to 177 amino acids with a calculated molecular weight of 18,700. The CypA gene is present at one copy/haploid genome in T.

Serum xanthine oxidase: origin, regulation, and contribution to control of trypanosome parasitemia.

African trypanosomiasis is caused by Salivarian trypanosomes, tsetse fly-transmitted protozoa that inhabit the blood plasma, lymph and interstitial fluids, and, in the case of Trypanosoma brucei species, also the cerebrospinal fluid of mammal hosts. Trypanosomiasis in people and domestic animals manifests as recurring waves of parasites in the blood and is typically fatal. In contrast, trypanosomiasis in Cape buffaloes, which are naturally selected to resist the disease, is characterized by the development of only one or a few waves of parasitemia, after which the infection becomes cryptic, being maintained by the presence of 1-20 mammal-infective organisms/ml of blood.

Recombinant tumor necrosis factor alpha does not inhibit the growth of African trypanosomes in axenic cultures.

Mice whose tumor necrosis factor alpha (TNF-alpha) genes were disrupted developed higher levels of parasitemia than wild-type mice following infection with Trypanosoma congolense IL1180 or T. brucei brucei GUTat3.1, confirming the results of earlier studies.