Aged ; Cardiomyopathy, Hypertrophic ; surgery ; Catheter Ablation ; methods ; Female ; Humans ; Male ; Middle Aged ; Ventricular Septum ; surgery

Besides its function as a pathogenicity determinant, the Tombusvirus P19 also serves as a suppressor of RNA interference (RNAi) by sequestering intracellular small RNAs such as the small interfering RNAs (siRNAs) and microRNAs (miRNAs). However, the effect of P19 on mammalian cells has not been evaluated before. A human embryonic kidney 293 cell line that stably expressed p19 (HEK293-p19) was generated. Flow cytometric analysis revealed that over-expression of P19 caused a significant accumulation of G2/M phase cells. Cell proliferation assays demonstrated a reduced DNA replication and cell growth in HEK293-p19 cells. Moreover, p19 altered the expression profiles of a number of cell cycle regulators in HEK293 cells, such as upregulafion of cyclin A1, CDK2, CDK4, CDK6, p18, cyclin D2, p19INK4d and E2F1, and downregulation of p15, cyclin A2, cyclin B1 and cyclin E1. Thus, the data strongly indicate that p19 might influence multiple G2/M regulators to cause G2/M arrest.

OBJECTIVETo obtain 1-4 IgG-like domains of mouse vascular endothelial growth factor receptor 2 (VEGFR2) fusion protein (mVEGFR2D1-4/GST) and identify its antiginicity and biological activity.

METHODSThe gene of mVEGFR2D1-4 was amplified by RT-PCR from 14-days embryos of Balb/c mice. The PCR product was cloned into pET-42a prokaryotic expression vector to construct the recombinant plasmid pET-42a-mVEGFR2D1-4, which was transformed into E. coli BL21 (DE3) strain for mVEGFR2D1-4/GST expression. The fusion protein was identified by SDS-PAGE and Western blotting, and the antigenicity of the protein purified by affinity chromatography was characterized by ELISA. The VEGF blocking effect of the purified protein in human umbilical vein endothelial cells (HUVECs) were evaluated in in vitro cell cultures.

RESULTSThe mVEGFR2D1-4 gene was obtained, which had an identical sequence to that retrieved in GenBank. The prokaryotic expression vector for mVEGFR2D1-4 was successfully constructed as confirmed by enzyme digestion and DNA sequencing. Both Western blotting and ELISA demonstrated the antigenicity of the purified mVEGFR2D1-4 fusion protein, which obviously blocked the effect of VEGF in promoting HUVEC proliferation in vitro.

CONCLUSIONThe mVEGFR2D1-4/GST fusion protein obtained shows a strong antigenicity and biological activity to facilitate further study of active anti-tumor immunotherapy targeting VEGFR2.

Animals ; Cell Proliferation ; Escherichia coli ; genetics ; metabolism ; Female ; Gene Expression ; Genetic Vectors ; Human Umbilical Vein Endothelial Cells ; Humans ; Mice ; Mice, Inbred BALB C ; Plasmids ; Recombinant Fusion Proteins ; genetics ; immunology ; isolation & purification ; Reverse Transcriptase Polymerase Chain Reaction ; Vascular Endothelial Growth Factor Receptor-2 ; genetics ; immunology ; isolation & purification