Author: Chiweshe SM, Steketee PC, Jayaraman S, Paxton E, Neophytou K, Erasmus H, Labuschagne M, Cooper A, MacLeod A, Grey FE, Morrison LJ
About this Publication:
Human and animal African trypanosomiasis are significant health and economic issues across much of sub-Saharan Africa. Effective control of AAT and potential eradication of HAT require affordable, sensitive and specific diagnostic tests for use in the field. Small RNAs are attractive disease biomarkers due to their stability, accessibility and available technologies for detection. Using RNAseq, we identified a trypanosome specific small RNA present at high concentrations in serum of infected cattle. This small RNA is from the non-coding 7SL RNA of the peptide signal recognition particle, and detected in the serum of infected cattle at significantly higher concentrations than in the parasite suggesting active processing and secretion. We detected the small RNA directly from serum without the need for pre-processing using a single step RT-qPCR assay. The small RNA can be detected before microscopical detection of parasitaemia and can also be detected during remission when no parasitaemia is detectable by microscopy. Small RNA concentrations dropped following treatment with trypanocides, demonstrating accurate prediction of active infection. The small RNA sequence is conserved between different species of trypanosome, but nucleotide differences within the sequence allow generation of highly specific assays to distinguish between infections with Trypanosoma brucei, Trypanosoma congolense and Trypanosoma vivax. Our findings identify a species-specific trypanosome small RNA that can be detected at high levels in the serum of cattle with active trypanosome infections, providing a basis for the development of a cheap, non-invasive and highly effective diagnostic test for trypanosomiasis.
Grant: Tryps2 Suppl
Subject Areas: Research and Development