Detection and molecular characterization of rabies virus in Mongolia during 2008-2010

Aim: We aimed to investigate the prevalence and molecular characterization of rabies virus (RABV) from wild and domestic animals in Mongolia during 2008-2010. Materials and Methods: Brain tissue samples were collected from 24 rabid animals in Zavkhan, Omnogovi, Tov, Dundgovi, Govi-Altai, Selenge, Ovorkhangai, and Khentii provinces in Mongolia. Herein, samples were included from 13 domestic animals (dogs, cattle, camels, sheep, and goat) and 11 wild animals (wolves and foxes) in this study. Direct fluorescent antibody (DFA) test and reverse transcriptase polymerase chain reaction (RT-PCR) were performed for detection of RABV, and positive samples were further processed for molecular characterization of the virus using nucleoprotein gene. Subsequently, the molecular characterization was determined based on the nucleoprotein gene. Results: Out of 24 samples, 22 samples were detected positive for RABV by DFA test, and its nucleoprotein gene was amplified in all of the 24 samples by RT-PCR. These Mongolian RABVs were classified within steppe-type virus clade by phylogenetic analysis of nucleoprotein gene sequences. This steppe-type virus clade was clearly divided by two Sub-clades (A and B). The most of Mongolian RABVs belongs to the Sub-clade A in the phylogenetic tree. Conclusion: These findings have clearly confirmed RABV in domestic and wild animals of Mongolia. Further molecular characterization indicated that this Mongolian strain is steppe-type virus clade consisting of two sub-clades; the Subclade A might be prevalent in Altai, Khangai, Khentii Mountains as a major genotype, whereas the Subclade B seems to be cosmopolitan in the steppe-type virus clade, is spread in northern central Eurasia

17-DMAG inhibits the multiplication of several Babesia species and Theileria equi on in vitro cultures, and Babesia microti in mice

Heat shock protein 90 (Hsp90) is a chaperone protein that stabilizes cells during stress or non-stress responses. Previous reports have shown that Hsp90 is a potential drug target to suppress the multiplication of several protozoan parasites. In this study, 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG), an Hsp90 inhibitor, was evaluated for its inhibitory effect on five in vitro cultures of Babesia and Theileria species, including B. bovis, B. bigemina, B. divergens, B. caballi, and T. equi, and on the multiplication of a B. microti–infected mouse model. 17-DMAG showed the inhibitory effect in all of the species tested. The half maximum inhibition concentration (IC50) of 17-DMAG on B. bovis, B. bigemina, B. divergens, B. caballi, and T. equi was 77.6 ± 2.9, 62.4 ± 1.9, 183.8 ± 3.2, 88.5 ± 9.6, and 307.7 ± 7.2 nM, respectively. The toxicity assay on MDBK and NIH/3T3 cell lines showed that 17-DMAG affected the viability of cells with an IC50 of 15.5 ± 4 and 8.8 ± 2 μM, respectively. Since the IC50s were much lower on the parasites than on the host cell lines, the selectivity index were high for all tested species. Furthermore, the two-drug combination of 17-DMAG with diminazene aceturate (DA) and atovaquone (AV) showed synergism or addition on in vitro cultures of Babesia and Theileria parasites. In the mouse model, 17-DMAG at a concentration of 30 mg/kg BW effectively inhibited the multiplication of B. microti. Moreover, if combined with DA or AV, 17-DMAG showed a comparable inhibition at the half dose. Taken together, these results indicate that 17-DMAG is a potent drug for treating piroplamosis. The data warrant further evaluation of 17-DMAG as an antibabesial drug and as an option in combination with atovaquone for the treatment of human babesiosis. Keywords: 17-DMAG, Babesia, Chemotherapeutic, Hsp90 inhibitor, Theileri