Construction of foot-and-mouth disease virus like particles-induced expression vectors and screening of BHK-21 cell pools / 生物工程学报

Transient expression is the major method to express foot-and-mouth disease virus (FMDV) capsid proteins in mammalian cells. To achieve stable expression of FMDV capsid proteins and efficient assembly of virus like particles (VLPs) in cells, the plasmids of piggyBac (PB) transposon-constitutive expression and PB transposon-tetracycline (Tet) inducible expression vectors were constructed. The function of the plasmids was tested by fluorescent proteins. By adding antibiotics, the constitutive cell pools (C-WT, C-L127P) expressing P12A3C (WT/L127P) genes and the inducible cell pools (I-WT, I-L127P) expressing P12A3C (WT/L127P) genes were generated. The genes of green fluorescent protein, 3C protease and reverse tetracycline transactivator (rtTA) were integrated into chromosome, which was confirmed by fluorescence observation and PCR testing. The cell pool I-L127P has a stronger production capacity of capsid proteins and VLPs, which was confirmed by Western blotting and enzyme linked immunosorbent assay (ELISA), respectively. In conclusion, inducing the chromosomal expression of FMDV capsid proteins was firstly reported, which may facilitate the technical process of mammalian production of FMDV VLPs vaccine and the construction of mammalian inducible expression systems for other proteins.

Methylation of p16 and p15 genes in multiple myeloma / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the frequency of p16 and p15 gene methylation in multiple myeloma (MM), and its relationship with bone marrow cell apoptosis and clinical outcome.</p><p><b>METHODS</b>Twenty-two patients with MM were studied to detect p16 and p15 gene methylation. Methylation-specific polymerase chain reaction (MSP) was used to detect gene methylation, and terminal transferase-mediated dUTP nick end-labeling (TUNEL) was used to detect cell apoptosis.</p><p><b>RESULTS</b>p16 and/or p15 gene methylatoin was detected in 10 of 22 patients (45.4%). There were 3 patients with p16 gene methylation, 9 patients with p15 gene methylation, and 2 patients with both genes methylation. The incidence of methylation of p15 gene was higher than that of p16 gene (P < 0.05). The patients with p16 and/or p15 gene methylation had a delayed cell apoptosis, poor response to chemotherapy, and a short over-all survival (OS).</p><p><b>CONCLUSION</b>The methylation of p16 and/or p15 gene plays a key role in MM apoptosis pathogenesis. The patients with both p16 and p15 gene methylation had a poor prognosis.</p>