ABSTRACT: Microtus fortis (M. fortis) is the only mammal in which the growth, development and maturation of schistosomes (Schistosoma japonicum) is prevented, resulting in the failure of the parasite to mature and complete its life cycle. MicroRNAs (miRNAs) are a class of endogenous, non-coding small RNAs, has been found to introduce a whole new layer of gene regulation in eukaryotes. The anti-schistosomiasis mechanosm of M. fortis may require the participation of miRNA-mediated gene expression. In the present study, the difference pathological change of different tissue such as liver, spleen and lung of M. fortis were observed by using haematoxylin-eosin staining. Also, the miRNA expression in different tissue of M. fortis and mice before challenge and 10 days post-infection with schistosomes were first compared using microRNA microarray analysis. Histological analyses showed that S. japonicum infection in M. fortis resulted in more intensive inflammatory response and pathologic change than mice. The microarray investigations showed that 388 miRNAs detected common expressed in the two species, and 11 miRNAs in liver, 25 miRNAs in spleen and 28 miRNAs in lung differentially expressed in non-permissive M. fortis while increased, decreased or nearly fixed in mice. Further studies of the differentially expressed miRNAs demonstrated that many important signal pathway were triggered after the S. japonicum infection in M. fortis rather than the mouse, such as the metabolism of some nutrient material such as fatty-acid, cholesterol, lipid, insulin, and carbohydrate; immune response such as B and T cell differentiation, monocyte differentiation, the inflammation, NF-kappaB binding, even the in innate immune system; Cell differentiation and apoptosis such as erythrocytic differentiation and targeting proapoptotic and antiapoptotic proteins. These results may provide new insights into general mechanisms of regulation in non-permissive M. fortis, exploit the potential miRNA regulatory networks and the interaction between parasites and different hosts, which provide valuable new information on schistosome biology and valuable information for the better understanding of schistosome development and host-parasite interactions. We collected liver, spleen and lung from control and 10 days post-infection with schistosomes of M. fortis, mice and rat, respectively.
