An improved method for the rescue of of recombinant Newcastle disease virus

Reverse genetics has been used to generate recombinant Newcastle disease virus with enhanced immunogenic properties for vaccine development. The system, which involves co-transfecting the viral antigenomic plasmid with three helper plasmids into a T7 RNA polymerase-expressing cell to produce viral progenies, poses a great challenge. We have modified the standard transfection method to improve the transfection efficiency of the plasmids, resulting in a higher titer of virus progeny production. Two transfection reagents (i.e., lipofectamine and polyethylenimine) were used to compare the transfection efficiency of the four plasmids. The virus progenies produced were quantitated with flow cytometry analysis of the infectious virus unit. The modified transfection method increased the titer of virus progenies compared with that of the standard transfection method

Development of a T7 RNA polymerase expressing cell line using lentivirus vectors for the recovery of recombinant Newcastle disease virus

The development of a T7 RNA polymerase (T7 RNAP) expressing cell line i.e. BSR T7/5 cells marks an improvement of reverse genetics for the recovery of recombinant Newcastle disease virus (rNDV). BSR T7/5 is developed by transient transfection of plasmid encoding T7 RNAP gene for rNDV rescue. However, the gene expression decreases gradually over multiple passages and eventually hinders the rescue of rNDV. To address this issue, lentiviral vector was used to develop T7 RNAP-expressing HEK293-TA (HEK293-TA-Lv-T7) and SW620 (SW620-Lv-T7) cell lines, evidenced by the expression of T7 RNAP after subsequent 20 passages. rNDV was rescued successfully using HEK293-TA-Lv-T7 clones (R1D3, R1D8, R5B9) and SW620-Lv-T7 clones (R1C11, R3C5) by reverse transfection, yielding comparable virus rescue efficiency and virus titres to that of BSR T7/5. This study provides new tools for rNDV rescue and insights into cell line development and virology by reverse genetics

Antiproliferative activity of methanolic extracts of genus Allium on human osteosarcoma SAOS-2 cells

Conventional treatments towards cancer bring along side effects to the patients. Plant extract treatments appear as new candidates for cancer treatment with fewer side effects. However, cytotoxicity effects of plant extracts on cancer are still lacking in scientific evidence. Allium plant extracts were hypothesed to able to inhibit growth of cancer cells. In this study, the cytotoxicity effects of two Allium plant extracts on Human osteosarcoma, Saos-2 cells were examined. Cell viability of Saos-2 cells was compared to the normal cells, Chang Liver Cells. Allium sativum fruit bodies and Allium ampeloprasum leaves were dried and blended into powder form. Then, they were extracted with methanol and evaporated to obtain crude extracts. Various concentrations of Allium extracts were used to treat the Human Saos-2 osteosarcoma cells. MTT assay was performed after 24, 48 and 72 hours of post treatment to evaluate the cytotoxicity effects. Allium sativum showed inducing of cell proliferation on Chang Liver Cells after 24h of treatment. In the other hand, it did not inhibit significant cell viability of Saos-2 cells for three different time slots. Allium ampeloprasum exhibit cytotoxicity towards both cell lines, but it kills more Chang Liver Cells than Saos-2 cells