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hUC-MSCs hold great promise in vitro neuronal differentiation and therapy for neurodegenerative disorders including Parkinson’s disease. Recent studies provided that Lmx1α play an important role in the midbrain dopamine cells differentiation. Neurturin is desired candidate gene for providing a neuroprotective to DA neurons. In this study, we investigated a novel neuronal differentiation strategy in vitro with Lmx1α and NTN. We transferred these two genes to hUC-MSCs by recombinant adenovirus combined with Lmx1α regulatory factor and other inductor to improve the efficiency of inducing. Then those induced cells were implanted into the striatum and substantia nigra of MPTP lesioned hemi-parkinsonian rhesus monkeys. Monkeys were monitored by using behavioral test for six months after implantation. The result showed that cells isolated from the umbilical cord were negative for CD45, CD34 and HLA-DR, but were positive for CD44, CD49d, CD29. After those cells were infected with recombinant adenovirus, RT-PCR result shows that both Lmx1α and NTN genes were transcribed in hUC-MSCs. We also observed that the exogenous were highly expressed in hUC-MSCs from immunofluorescence and western blot. Experiments in vitro have proved that secretion NTN could maintain the survival of rat fetal midbrain dopaminergic neurons. After hUC-MSCs were induced with endogenous and exogenous factors, the mature neurons specific gene TH, Pitx3 was transcripted and the neurons specific protein TH, β-tubulinIII, NSE, Nestin, MAP-2 was expressed in those differentiated cells. In addition, the PD monkeys, transplanted with the induced cells demonstrated the animals’ symptoms amelioration by the behavioral measures. Further more, pathological and immunohistochemistry data showed that there were neuronal-like cells survived in the right brain of those PD monkeys, which may play a role as dopaminergic neurons. The findings from this study may help us to better understand the inside mechanisms of PD pathogenesis and may also help developing effective therapy for Parkinson’s disease.

Rotaviruses are double-stranded RNA viruses that are a major cause of viral diarrhea in infants. Examining virus-host cell interaction is important for elucidating mechanisms of virus proliferation in host cells. Viruses can create an environment that promotes their survival and self-proliferation by encoding miRNAs or miRNA-like molecules that target various host cell. However, it remains unclear whether RNA viruses encode viral miRNAs, and their regulation mechanisms are largely unknown. We previously performed deep sequencing analysis to investigate rotavirus-encoded miRNAs, and identified the small RNA molecule Chr17_1755, which we named RV-vsRNA1755. In our present study, we determined that RV-vsRNA1755 is encoded by the rotavirus NSP4 gene and that it targets the host cell IGF1R, which is part of the PI3K/Akt pathway. We further explored the biological characteristics and functions of RV-vsRNA1755.Our results suggest that rotavirus adapts to manipulate PI3K/Akt signaling at early phases of infection. RV-vsRNA1755 targets IGF1R, blockading the PI3K/Akt pathway and triggering autophagy, but it ultimately inhibits autophagy maturation. A mechanism through which rotavirus encodes a virus-like small RNA (RV-vsRNA1755) that triggers autophagy by targeting the host cell IGF1R gene was revealed. These data provide a theoretical basis for therapeutic drug screening targeting RV-vsRNA1755.

Aims: A novel integrated cell culture/strand-specific reverse transcriptase-polymerase chain reaction (RT-PCR) assay was established for detection of infectious hepatitis A virus (HAV). Methods and Results:The specificity of tagged RT-PCR was assessed using HAV genomic positive-strand RNA extracted from HAV virions as reference. Water samples artificially contaminated with infectious or formalininactivated HAV were subjected to integrated cell culture (ICC)/RT-PCR and ICC/strand-specific RT-PCR assays respectively. The tagged RT-PCR had high specificity for HAV negative-strand RNA. By demonstrating the formation of negative-strand RNA replicative intermediate, ICC/strand-specific RT-PCR can distinguish between infectious and non-infectious HAV. The described method detected infectious HAV at inoculation level of 10 0 TCID 50 per flask within 4 days. Conclusions: The ICC/strand-specific RT-PCR is a novel, rapid, sensitive and reliable method for detection of infectious HAV. Significance and Impact of the Study: Coupled with a suitable virus concentration and purification system, ICC/strand-specific RT-PCR will provide a novel and rapid method for detection of infectious HAV in clinical, environmental and food samples. This assay may be used as an alternative method to test the effective inactivation of inactivated virus vaccines. It may also be adapted to assess the efficacy of disinfection of HAV and enteric viruses in foods and water.

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