Phylogenetic and Molecular Analysis of the Porcine Epidemic Diarrhea Virus in Mexico during the First Reported Outbreaks (2013-2017)

The characteristics of the whole PEDV genome that has circulated in Mexico from the first outbreak to the present are unknown. We chose samples obtained from 2013 to 2017 and sequenced them, which enabled us to identify the genetic variation and phylogeny in the virus during the first four years that it circulated in Mexico. A 99% identity was found among the analyzed pandemic strains; however, the 1% difference affected the structure of the S glycoprotein, which is essential for the binding of the virus to the cellular receptor. The S protein induces the most efficacious antibodies; hence, these changes in structure could be implicated in the clinical antecedents of the outbreaks. Antigenic changes could also help PEDV avoid neutralization, even in the presence of previous immunity. The characterization of the complete genome enabled the identification of three circulating strains that have a deletion in ORF1a, which is present in attenuated Asian vaccine strains. The phylogenetic analysis of the complete genome indicates that the first PEDV outbreaks in Mexico were caused by INDEL strains and pandemic strains related to USA strains; however, the possibility of the entry of European strains exists, which may have caused the 2015 and 2016 outbreaks.

Differential Transcription of SOCS5 and SOCS7 in Multiple Sclerosis Patients Treated with Interferon Beta or Glatiramer Acetate

The participation of proinflammatory cytokines in the progression of Multiple Sclerosis (MS) has been well documented. Cytokines activate the JAK-STAT pathway, in which the suppressors of cytokine signaling (SOCS) exert a negative feedback. This paper analyzes the levels of SOCS5 and SOCS7 transcripts, quantified by RT-qPCR, in MS patients, and the concentrations of proinflammatory cytokines, IFN-γ, IL17, and IL6, determined by ELISA. Samples of peripheral blood were obtained from MS patients in the relapsing–remitting phase, treated with IFN-β or glatiramer acetate (GA), and from healthy individuals. SOCS7 mRNA was significantly higher in patients treated with GA (1.36 ± 0.23) than in those treated with IFN-β (0.65 ± 0.1). Regarding gender, the level of SOCS5 and SOCS7 transcripts were similar between MS and healthy females; in MS males, the level of SOCS7 transcripts were significantly lower (0.59 ± 0.03) than in healthy males (1.008 ± 0.05). Plasmatic levels of IFN-γ were significantly higher in MS patients (60 pg/mL, range 0–160) than in healthy subjects (0 range, 0–106). The same pattern was observed in MS patients treated with IFN-β (68 pg/mL, range 0–160) compared to patients treated with GA (51 pg/mL, range 0–114), and in MS females (64 pg/mL, range 0–161) compared to healthy females (0, range 0–99). We hypothesize that the increase in SOCS7 transcription in patients treated with GA could partially explain the action mechanism of this drug, while the increase in the concentration of IFN-γ in MS patients could help elucidate the immunopathology of the disease.

Expression analysis of ST3GAL4 transcripts in cervical cancer cells

ST3GAL4 gene expression is altered in different cancer types, including cervical cancer. Several mRNA transcripts have been reported for this gene; however, their expression levels in cervical cancer have not been analyzed. ST3GAL4 encodes for β‑galactosidase α‑2,3‑sialyltransferase 4, involved in the biosynthesis of the tumour antigens sLe(x) and sulfo‑sLe(x). The present study evaluated the presence of three mRNA variants (V1, V2 and V3) in cervical cancer cell lines, detecting the three variants. Additionally, the expression level of the V1 transcript of the ST3GAL4 gene was determined by reverse transcription‑quantitative polymerase chain reaction in cervical cell lines and in normal, premalignant and cervical cancer tissue. The V1 transcript of the ST3GAL4 demonstrated significant decreased expression in premalignant and malignant cervical tissues. The results suggested that deregulation of this gene could occur prior to the presence of cancer and demonstrated the importance of evaluating the expression level of V1, and its association with disease progression.

Upregulation of the Suppressors of Cytokine Signaling 1 and 3 Is Associated with Arrest of Phosphorylated-STAT1 Nuclear Importation and Reduced Innate Response in Denguevirus-Infected Macrophages

To clarify whether the suppressors of cytokine signaling (SOCS) are associated with denguevirus (DENV) evasion of the antiviral response, we analyzed the expression kinetics of SOCS1 and SOCS3 and of the antiviral genes MxA and OAS during DENV infection of U937 macrophages that were or not treated with interferon (IFN)-α. DENV infection produced a viral titer three times higher in untreated than in IFN-α-treated cells (p < 0.001 at 72 h postinfection [p.i.]). Partial inhibition of DENV replication was associated with reduced expression of MxA and OAS antiviral genes as well as higher SOCS1 and SOCS3 expression in DENV-infected cells than in cells treated only with IFN-α. Complete loss of phosphorylated-signal transducer and activator of transcription (p-STAT)2 and reduced nuclear importation of p-STAT1 were observed in DENV-infected cells compared to IFN-α treatment that induced p-STAT1 and p-STAT2. Our data thus suggest that overexpression of SOCS1 and SOCS3 induced by DENV infection leads to impairment of antiviral response through the inhibition of STAT functionality.

[Alternative splicing regulation: implications in cancer diagnosis and treatment]

The accurate expression of the genetic information is regulated by processes like mRNA splicing, proposed after the discoveries of Phil Sharp and Richard Roberts, who demonstrated the existence of intronic sequences, present in almost every structural eukaryotic gene, which should be precisely removed. This intron removal is called "splicing", which generates different proteins from a single mRNA, with different or even antagonistic functions. We currently know that alternative splicing is the most important source of protein diversity, given that 70% of the human genes undergo splicing and that mutations causing defects in this process could originate up to 50% of genetic diseases, including cancer. When these defects occur in genes involved in cell adhesion, proliferation and cell cycle regulation, there is an impact on cancer progression, rising the opportunity to diagnose and treat some types of cancer according to a particular splicing profile.

Differential sensitivity to interferon influences the replication and transcription of Urabe AM9 mumps virus variants in nerve cells

Urabe AM9 mumps virus vaccine causes post-vaccination meningitis. Two variants of Urabe AM9 virus differ in their replication efficiency in human nerve cells, HN-A(1081) variant being more neurotropic than HN-G(1081). The effect of interferon (IFN) on viral replication and transcription was analyzed. Priming of nerve cells with IFN reduced more significantly the replication of HN-G(1081) variant (from 10(2.5) to 10(1.3) TCID(50)) than that of HN-A(1081) (from 10(3.5) to 10(2.6) TCID(50)). IFN-priming also reduced the transcription of HN-G(1081) genes, but not of HN-A(1081). The effect of viral infection on the transcription of cellular IFN responsive genes was analyzed. HN-A(1081) virus reduced the transcription of STAT1, STAT2, p48 and MxA in both unprimed and IFN-primed cells; whereas HN-G(1081) virus just reduced MxA transcription. Since rubulavirus V protein inhibits IFN signaling, the V mRNA was cloned and sequenced, finding that HN-G(1081) but not HN-A(1081) presented three extra G in the P/V edition site, producing the insertion of Gly156 in the V protein. Our results suggest that the replication efficiency of Urabe AM9 mumps virus variants is influenced by their sensitivity to interferon and their capacity to reduce the antiviral response.