ABSTRACT
Objective To observe the effect of brain-derived microvesicles (BDMVs) on cytoskeleton in human umbilical vein endothelial cells (HUVECs).Methods BDMVs were prepared in vitro and identified by transmission electron microscopy and particle size identification.HUVECs were co-cultured with PKH26-1abeled BDMVs for 0.5,1,and 2 h;flow cytometry was used to detect the phagocytosis of HUVECs for BDMVs at different time points.HUVECs cultured in vitro were divided into control group,BDMVs treatment group and nimodipine treatment group;cells in the BDMVs treatment group were given 1.5× 107/mL BDMVs;cells in the nimodipine treatment group were pretreated with 2 μg nimodipine (0.2 mg/mL) for 10 min,and then,given 1.5×107/mL BDMVs.After being stained with rhodamine-labeled phalloidin,the fluorescence intensity and number of stress fibers of fibroactin in HUVECs were observed by laser confocal microscopy.Results BDMVs had complete membrane structure with a diameter of 100-1000 nm under transmission electron microscopy.The proportion of cells phagocytizing BDMVs increased significantly with prolonged incubation time,enjoying significant differences (0.5h:22.7%±1.2%;1 h:52.3%±1.3%;2h:71.6%±1.9%,P<0.05).Laser confocal microscopy showed that,as compared with the control group,the fluorescence intensity ofcytoskeletal protein was obviously increased and the number of stress fibers increased was obviously larger in the BDMVs treatment group.As compared with those in the BDMVs treatment group,the fluorescence intensity of cytoskeletal protein was decreased and the number of stress fibers was obviously smaller in the nimodipine group.Conclusion The role of BDMVs in phagocytosis of HUVECs becomes stronger as time being prolonged,and BDMVs phagocytosis leads to cytoskeletal remodeling,which can be partially blocked by nimodipine.
ABSTRACT
The genomic diversity of Avian leukosis virus subgroup J (ALV-J) was investigated in an experimentally infected chicken. ALV-J variants in tissues from four different organs of the same bird were re-isolated in DF-1 cells, and their gp85 gene was amplified and cloned. Ten clones from each organ were sequenced and compared with the original inoculum strain, NX0101. The minimum homology of each organ ranged from 96.7 to 97.6%, and the lowest homology between organs was only 94.9%, which was much lower than the 99.1% homology of inoculum NX0101, indicating high diversity of ALV-J, even within the same bird. The gp85 mutations from the left kidney, which contained tumors, and the right kidney, which was tumor-free, had higher non-synonymous to synonymous mutation ratios than those in the tumor-bearing liver and lungs. Additionally, the mutational sites of gp85 gene in the kidney were similar, and they differed from those in the liver and lung, implying that organ- or tissue-specific selective pressure had a greater influence on the evolution of ALV-J diversity. These results suggest that more ALV-J clones from different organs and tissues should be sequenced and compared to better understand viral evolution and molecular epidemiology in the field.