Porcine deltacoronavirus nonstructural protein 2 inhibits type I and III IFN production by targeting STING for degradation.

Porcine deltacoronavirus (PDCoV) is an enteropathogenic coronavirus that has been reported to use various strategies to counter the host antiviral innate immune response. The cGAS-STING signalling pathway plays an important role in antiviral innate immunity. However, it remains unclear whether PDCoV achieves immune evasion by regulating the cGAS-STING pathway. Here, we demonstrated that the nonstructural protein 2 (nsp2) encoded by PDCoV inhibits cGAS-STING-mediated type I and III interferon (IFN) responses via the regulation of porcine STING (pSTING) stability. Mechanistically, ectopically expressed PDCoV nsp2 was found to interact with the N-terminal region of pSTING. Consequently, pSTING was degraded through K48-linked ubiquitination and the proteasomal pathway, leading to the disruption of cGAS-STING signalling. Furthermore, K150 and K236 of pSTING were identified as crucial residues for nsp2-mediated ubiquitination and degradation. In summary, our findings provide a basis for elucidating the immune evasion mechanism of PDCoV and will contribute to the development of targets for anti-coronavirus drugs.

p53 promotes ZDHHC1-mediated IFITM3 palmitoylation to inhibit Japanese encephalitis virus replication.

The tumor suppressor p53 as an innate antiviral regulator contributes to restricting Japanese encephalitis virus (JEV) replication, but the mechanism is still unclear. The interferon-induced transmembrane protein 3 (IFITM3) is an intrinsic barrier to a range of virus infection, whether IFITM3 is responsible for the p53-mediated anti-JEV response remains elusive. Here, we found that IFITM3 significantly inhibited JEV replication in a protein-palmitoylation-dependent manner and incorporated into JEV virions to diminish the infectivity of progeny viruses. Palmitoylation was also indispensible for keeping IFITM3 from lysosomal degradation to maintain its protein stability. p53 up-regulated IFITM3 expression at the protein level via enhancing IFITM3 palmitoylation. Screening of palmitoyltransferases revealed that zinc finger DHHC domain-containing protein 1 (ZDHHC1) was transcriptionally up-regulated by p53, and consequently ZDHHC1 interacted with IFITM3 to promote its palmitoylation and stability. Knockdown of IFITM3 significantly impaired the inhibitory role of ZDHHC1 on JEV replication. Meanwhile, knockdown of either ZDHHC1 or IFITM3 expression also compromised the p53-mediated anti-JEV effect. Interestingly, JEV reduced p53 expression to impair ZDHHC1 mediated IFITM3 palmitoylation for viral evasion. Our data suggest the existence of a previously unrecognized p53-ZDHHC1-IFITM3 regulatory pathway with an essential role in restricting JEV infection and provide a novel insight into JEV-host interaction.

Modified balloon-stent kissing technique avoid side-branch compromise for simple true bifurcation lesions.

BACKGROUND: Coronary bifurcation remains one of the most challenging lesion subsets in interventinal cardiology. Provisional stenting (PS) is the dominate technique for bifurcation lesions, but the key problem is the deterioration of side branch. Balloon-stent kissing technique (BSKT) as a new systematic approach which is based on modified jailed balloon technique is applied to improve the procedure success. In our center, we proposed a modified balloon-stent kissing technique(M-BSKT), which routine usage of proximal optimizing technique (POT) after rewiring was added as an optimization step to BSKT. Thus, whether M-BSKT for addressing simple true coronary bifurcation lesions can provide more benefits in intra-operation effect and long term outcomes is still unknown. METHODS: A cohort of 120 consecutive patients underwent Percutaneous Coronary Intervention (PCI) with simple true coronary bifurcation lesions satisfied the criteria were included in this retrospective, single-center registry. To assemble a cohort with similar baseline characteristics, a 1:1 propensity-matched score was used. The primary outcomes were the rate of device and procedural success, the situation of side branch (SB) after main vessel (MV) inflation and the complications during intra-operative. The secondary outcomes were the clinical prognosis at 12 months such as rehospitalization for unstable angina and MACEs. RESULTS: Before propensity matching, there were no significant differences in primary and secondary outcomes between two groups. After propensity-matched was used, 68 patients with similar propensity scores were included. At immediate procedural, M-BSKT was associated with a lower risk of SB deterioration and the application of final kissing balloon inflation (FKBI)[P = 0.036]. For ACS patients, besides the significant differences of immediate SB deterioration [P = 0.014] and FKBI application [P = 0.033], the incidence of TIMI flow< 3 in the PS was statistically significant higher than M-BSKT [P= 0.042]. The prognosis at 12 months such as rehospitalization for unstable angina and MACEs were similar for two groups [P = 0.613]. CONCLUSION: These observations prove that the M-BSKT enables side branch to be better protected in simple true bifurcation lesions, by a narrow margin. It may improve the angiographic outcomes about side branch deterioration and final kissing balloon performing compared with PS, especially in ACS patients. However, long-term clinical outcomes did not differ between patients treated for M-BSKT and PS at 12 months.

Porcine reproductive and respiratory syndrome virus counteracts type I interferon-induced early antiviral state by interfering IRF7 activity.

Porcine reproductive and respiratory syndrome (PRRS) is an economically important disease with a significant impact on the pig industry. It is caused by PRRS virus (PRRSV), which predominantly infects and replicates in porcine pulmonary alveolar macrophages (PAMs). We pretreated PAMs with porcine interferon (IFN)-α to induce an antiviral state within the cells and subsequently infected them with highly pathogenic PRRSV. Changes in global gene expression in IFN-α-pretreated PAMs in response to PRRSV infection were determined by RNA-sequence analysis and confirmed by real-time PCR. We found that IRF7 and other antiviral interferon stimulating genes (ISG)s were suppressed by PRRSV infection. Further studies demonstrated that PRRSV could down-regulate the expression of IRF7 by the non-structure protein 7 (nsp7). In conclusion, PRRSV infection had a strong immunosuppressive effect of IFN. PRRSV nsp7 inhibits the expression of IRF7, thereby down-regulating the expression of IFN and downstream ISGs and facilitated the virus to replicate.

The effect of EDTA root conditioning on periodontal surgery outcome: A meta-analysis.

OBJECTIVE: Chemical root conditioning is a procedure to remove the smear layer, which influences periodontal healing. The purpose of this study was to determine the effect of using ethylenediaminetetraacetic acid (EDTA) as a root conditioning agent on periodontal surgery outcomes. METHOD AND MATERIALS: The databases searched from their earliest records to February 2015 included Pubmed, Embase, the Cochrane library, and ISI Web of Science. Quality assessment of the methodologies of all the included studies and data was performed with Review Manager software. Probing depth (PD) and clinical attachment level (CAL) were analyzed using inverse variance. RESULTS: The evaluation of the three articles that met the inclusion criteria showed that the differences between the EDTA groups and the control groups were not statistically significant (6 months PD: mean difference [MD] = -0.15 mm, Z = 1.09, P = .27; CAL: MD = 0.15 mm, Z = 0.89, P = .37). CONCLUSION: EDTA was not able to significantly improve the PD and CAL. A positive outcome of using EDTA as a root conditioning agent was not evident. Thus, future research should focus on EDTA in combination with other drugs or a better alternative drug to EDTA.

[Inhibitory effects of high mobility group chromosomal protein N2 on human tongue carcinoma transplanted in nude mice].

OBJECTIVE: To evaluate the inhibitory effect of high mobility group chromosomal protein N2 (HMGN2) on human tongue carcinoma tumor in nude mice. METHODS: A transplantation tumor model in nude mice was constructed by injecting Tca8113 cells. After a week, negative control groups, masculine control groups, and HMGN2 groups were established. Cell culture of the three groups were separately injected with washing buffer II, cis-dichlorodiamineplatinum (DDP), and HMGN2 protein. The tumors were moved after four treatments, and then analyzed by hematoxylin-eosin (HE) staining. RESULTS: A transplanted tumor model was established successfully. The volumes of HMGN2 groups and masculine control groups were smaller than those of the negative groups. Mouse weight did not differ among the three groups. Average tumor weight of the negative group was (0.38 +/- 0.19)g, that of the HMGN2 group was (0.21 +/- 0.15)g, and that of the DDP group was (0.23 +/- 0.16)g. These factors indicated no statistically significant difference among the three groups. The tumor inhibitory rate of HMGN2 group was 45.71%, and that of the positive group was 39.44%. Based on evaluation by naked eye, the tumor in the negative group was larger than that in other groups. In addition, cell necrosis was observed during HE staining. CONCLUSION: HMGN2 could significantly inhibit growth of the transplanted tumor in nude mice.

Nucleosome-binding protein HMGN2 exhibits antitumor activity in oral squamous cell carcinoma.

Natural killer (NK) cells and cytolytic T lymphocytes (CTLs) serve as effectors in the antitumor response. High mobility group nucleosomal binding domain 2 (HMGN2) is a candidate effector molecule involved in CTL and NK cell function. In the current study, recombinant human HMGN2 was isolated and purified from transformed Escherichia coli. Tca8113 cells, an oral squamous cell carcinoma line, were treated with a variety of HMGN2 protein concentrations and cell growth was analyzed. HMGN2 significantly inhibited the growth of Tca8113 cells and was predicted to arrest cells in the S phase. Moreover, HMGN2 treatment increased the apoptosis rate of Tca8113 cells. Western blotting indicated the upregulation of p53 and Bax proteins, whereas Bcl-2 was significantly downregulated. In addition, caspase-3 was found to be activated. Furthermore, the HMGN2 protein may suppress the growth of Tca8113 cells in vivo. The results of the current study indicated that the HMGN2 protein may inhibit the growth of oral squamous cell carcinoma and HMGN2 may represent an antitumor effector molecule of CTL or NK cells.

[Study on prohibition of high mobility group chromosomal protein N2 against human oral squamous cell carcinoma in vitro].

OBJECTIVE: Take human oral squamous cell carcinoma Tca8113 as experimental model, and study the anti oral squamous cell carcinoma activity of high mobility group chromosomal protein N2 (HMGN2) molecule. METHODS: Train a large number of recombinant human HMGN2 expression vector Escherichia coli BL21. HMGN2 was expressed under isopropyl-1-thio-beta-galactopyranoside (IPTG) induction and purified by B-PER GST Fusion Protein Purification Kit. A variety of concentrations HMGN2 were added to cell culture medium, cells were tested by MTT, Hoechst 33342 fluorescence staining, flow cytometry assay and Western-blot. RESULTS: MTT results proved that HMGN2 could significantly inhibit human oral squamous cell carcinoma Tca8113 growth. Hoechst 33342 fluorescence staining, flow cytometry assay test and Western-blot proved HMGN2 could make Tca8113 cells morphological change, make Tca8113 cells block in S period of cell cycle and strongly promote Tca8113 cells to apoptosis. CONCLUSION: HMGN2 can promote apoptosis of oral squamous cell carcinoma cells.