Immunogenicity and Antigenicity of the Ectodomain of Rabies Virus Glycoprotein Stably Expressed in HEK293T Cells.

Rabies continues to be a huge threat to public health. The rabies virus envelope glycoprotein (RABV G) is a major rabies virus antigen and contains neutralizing epitopes, which are primary candidates for subunit vaccines and diagnostic antigens. However, the production and purification of rRABV G while retaining its antigenic and immunogenic remains to be a challenge. Here, we aimed to establish a platform for rRABV G production and purification, and determine the immunogenicity and antigenicity of rRABV G. The cDNA fragment encoding the soluble form of RABV G was synthesized and cloned into a lentiviral expressing vector. Recombinant lentiviral vector LV-CMV-RABV G-eGFP was packaged, titered, and then transduced into HEK 293T cells. The cell culture supernatant was purified using nickel affinity chromatography and subsequently confirmed through Western Blot analysis and indirect enzyme-linked immunosorbent assay (ELISA). The ELISA utilized human sera obtained from individuals who had been vaccinated with the human commercial Purified Vero Cells Rabies Vaccine (PVRV). Notably, we observed a neutralizing antibody response in immunized pigs rather than in mice. This discrepancy could potentially be attributed to factors such as the instability of the rRABV G protein, variations in host responses, and variances in the adjuvant used. Taking all these findings into account, the rRABV G protein generated in this study exhibits promise as a potential vaccine candidate for the prevention of rabies.

microRNA-221 Enhances MYCN via Targeting Nemo-like Kinase and Functions as an Oncogene Related to Poor Prognosis in Neuroblastoma.

Purpose:MYCN is one of the most well-characterized genetic markers of neuroblastoma. However, the mechanisms as to how MYCN mediate neuroblastoma tumorigenesis are not fully clear. Increasing evidence has confirmed that the dysregulation of miRNAs is involved in MYCN-mediated neuroblastoma tumorigenesis, supporting their potential as therapeutic targets for neuroblastoma. Although miR-221 has been reported as one of the upregulated miRNAs, the interplay between miR-221 and MYCN-mediated neuroblastoma progression remains largely elusive.Experimental Design: The expression of miR-221 in the formalin-fixed, paraffin-embedded tissues from 31 confirmed patients with neuroblastoma was detected by locked nucleic acid-in situ hybridization and qRT-PCR. The correlation between miR-221 expression and clinical features in patients with neuroblastoma was assessed. The mechanisms as to how miR-221 regulate MYCN in neuroblastoma were addressed. The effect of miR-221 on cellular proliferation in neuroblastoma was determined both in vitro and in vivoResults: miR-221 was significantly upregulated in neuroblastoma tumor cells and tissues that overexpress MYCN, and high expression of miR-221 was positively associated with poor survival in patients with neuroblastoma. Nemo-like kinase (NLK) as a direct target of miR-221 in neuroblastoma was verified. In addition, overexpression of miR-221 decreased LEF1 phosphorylation but increased the expression of MYCN via targeting of NLK and further regulated cell cycle, particularly in S-phase, promoting the growth of neuroblastoma cells.Conclusions: This study provides a novel insight for miR-221 in the control of neuroblastoma cell proliferation and tumorigenesis, suggesting potentials of miR-221 as a prognosis marker and therapeutic target for patients with MYCN overexpressing neuroblastoma. Clin Cancer Res; 23(11); 2905-18. ©2016 AACR.

[ß-arrestin1 promotes chronic myeloid leukemia cell proliferation by activating JNK signaling pathway].

OBJECTIVE: To investigate the signaling pathways involved in ß-arrestin1-induced proliferation of K562 cells. METHODS: We established stable cell lines K562-siß1 and K562-ß1 by lentivirus-mediated ß-arrestin1 knock-down or overexpression in K562 cells, with cells transfected with non-specific siRNA as the control (K562-Ctrl). The proliferation of these cells were evaluated by cell counting and CCK-8 assays. Western blotting was used to detect the expression of JNK and p-JNK in the cells, and co-immunoprecipitation (Co-IP) assay was employed to investigate the interaction between ß-arrestin1 and Src. RESULTS: K562-ß1 cells showed significantly greater but K562-siß1 cells had significantly lower proliferation ability and cell survival rate than K562-Ctrl cells. Western blotting showed that ß-arrestin1 specifically enhanced the expression of p-JNK, and the JNK inhibitor SP600125 obviously suppressed p-JNK and cell proliferation of K562 cells. Co-IP assay revealed the binding of ß-arrestin1 to Src. CONCLUSIONS: In K562 cells, ß-arrestin1 activates JNK signaling pathway by binding to Src to promote the cell proliferation.