Open AccessDetection of Circulating Parasite-Derived MicroRNAs in Filarial Infections
Author(s) -
Lucienne Tritten,
Erica Burkman,
Andrew R. Moorhead,
Mohamed Satti,
James Geary,
Charles D. Mackenzie,
Timothy G. Geary
Publication year - 2014
Publication title -
plos neglected tropical diseases
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.99
H-Index - 135
eISSN - 1935-2735
pISSN - 1935-2727
DOI - 10.1371/journal.pntd.0002971
Subject(s) - biology , dirofilaria immitis , parasite hosting , onchocerca volvulus , microrna , brugia pahangi , onchocerca , infectivity , dirofilaria , virology , microfilaria , filariasis , immunology , helminths , onchocerciasis , virus , gene , genetics , world wide web , computer science
Filarial nematodes cause chronic and profoundly debilitating diseases in both humans and animals. Applications of novel technology are providing unprecedented opportunities to improve diagnosis and our understanding of the molecular basis for host-parasite interactions. As a first step, we investigated the presence of circulating miRNAs released by filarial nematodes into the host bloodstream. miRNA deep-sequencing combined with bioinformatics revealed over 200 mature miRNA sequences of potential nematode origin in Dirofilaria immitis -infected dog plasma in two independent analyses, and 21 in Onchocerca volvulus -infected human serum. Total RNA obtained from D. immitis -infected dog plasma was subjected to stem-loop RT-qPCR assays targeting two detected miRNA candidates, miR-71 and miR-34. Additionally, Brugia pahangi -infected dog samples were included in the analysis, as these miRNAs were previously detected in extracts prepared from this species. The presence of miR-71 and miR-34 discriminated infected samples (both species) from uninfected samples, in which no specific miRNA amplification occurred. However, absolute miRNA copy numbers were not significantly correlated with microfilaraemia for either parasite. This may be due to the imprecision of mf counts to estimate infection intensity or to miRNA contributions from the unknown number of adult worms present. Nonetheless, parasite-derived circulating miRNAs are found in plasma or serum even for those species that do not live in the bloodstream.