Isolation and Characterization of a New T-Even Bacteriophage, CEV1, and Determination of Its Potential To Reduce Escherichia coli O157:H7 Levels in Sheep

Bacteriophage CEV1 was isolated from sheep resistant to Escherichia coli O157:H7 colonization. In vitro, CEV1 efficiently infected E. coli O157:H7 grown both aerobically and anaerobically. In vivo, sheep receiving a single oral dose of CEV1 showed a 2-log-unit reduction in intestinal E. coli O157:H7 levels within 2 days compared to levels in the controls

Molecular and phylogenetic characterization of novel papillomaviruses isolated from oral and anogenital neoplasms of Japanese macaques (Macaca fuscata)

Papillomaviruses (PVs) are a diverse group of host species-specific DNA viruses, etiologically linked with various benign and malignant neoplasms of cutaneous and mucosal epithelia. Here, we describe the detection and characterization of the first two PVs naturally infecting Japanese macaques (Macaca fuscata), including the determination of their etiological association(s) with the development of original neoplasms. The molecular and phylogenetic analyses were performed on complete genome sequences of Macaca fuscata PV types 1 (MfuPV1) and 2 (MfuPV2), which were completely sequenced in samples of a malignant oral tumor and benign anogenital neoplasm of Japanese macaques, respectively. Subsequently, two type-specific quantitative real-time PCRs were developed to estimate viral loads of MfuPV1 and MfuPV2 and to evaluate their etiological roles. The in silico molecular analyses revealed that both viral genomes encode characteristic PV proteins with conserved functional domains and have a non-coding genomic region with regulatory sequences to regulate and complete the viral life cycle. However, additional experimental evidence is needed to finally confirm the presence and biological functionality of the molecular features of both novel PVs. While MfuPV1, together with PVs identified in other macaques, is classified into the Alphapapillomavirus (Alpha-PV) species 12, MfuPV2 is most likely a representative of the novel viral species within the Alpha-PV genus. Their relatively high viral loads suggest that both PVs are etiologically linked with the development of the original neoplasms

KSHV oral shedding and plasma viremia result in significant changes in the extracellular tumorigenic miRNA expression profile in individuals infected with the malaria parasite

<div><p>Kaposi's sarcoma herpesvirus (KSHV) is the etiological agent of Kaposi’s sarcoma (KS). Both KSHV and HIV infections are endemic in Uganda, where KS is among the most common cancers in HIV-infected individuals. Recent studies examined the use of small RNAs as biomarkers of disease, including microRNAs (miRNAs), with viral and tumor-derived miRNAs being detected in exosomes from individuals with KSHV-associated malignancies. In the current study, the host and viral extracellular mature miRNA expression profiles were analyzed in blood of KS-negative individuals in Uganda, comparing those with or without KSHV detectable from the oropharynx. We observed increased levels of cellular oncogenic miRNAs and decreased levels of tumor-suppressor miRNAs in plasma of infected individuals exhibiting oral KSHV shedding. These changes in host oncomiRs were exacerbated in people co-infected with HIV, and partially reversed after 2 years of anti-retroviral therapy. We also detected KSHV miRNAs in plasma of KSHV infected individuals and determined that their expression levels correlated with KSHV plasma viremia. Deep sequencing revealed an expected profile of small cellular RNAs in plasma, with miRNAs constituting the major RNA biotype. In contrast, the composition of small RNAs in exosomes was highly atypical with high levels of YRNA and low levels of miRNAs. Mass spectrometry analysis of the exosomes revealed eleven different peptides derived from the malaria parasite, <i>Plasmodium falciparum</i>, and small RNA sequencing confirmed widespread plasmodium co-infections in the Ugandan cohorts. Proteome analysis indicated an exosomal protein profile consistent with erythrocyte and keratinocyte origins for the plasma exosomes. A strong correlation was observed between the abundance of Plasmodium proteins and cellular markers of malaria. As <i>Plasmodium falciparum</i> is an endemic pathogen in Uganda, our study shows that co-infection with other pathogens, such as KSHV, can severely impact the small RNA repertoire, complicating the use of exosome miRNAs as biomarkers of disease.</p></div

Small RNA biotypes distribution in plasma exosomes.

<p>Segments of the bar indicate the percent of reads attributed to each RNA type among all the small RNA reads that mapped to the human reference genome (hg19).</p

Patient demographics and viral status.

<p>Patient demographics and viral status.</p

MiRNA levels of expression in HIV infected patients before and after ART treatment.

<p>MicroRNAs levels of expression were determined using the nanoString microRNA platform on total RNA isolated from plasma samples collected before and after 2 years of ART therapy. P values indicated were calculated using a ratio paired t-test. The respective level of expression measured in KSHV+/HIV- individuals (median values) is shown in dashed line.</p

Plasma levels of tumor suppressor miRNAs are decreased in individuals with detectable KSHV oral shedding.

<p>The expression levels of cellular miRNAs in total RNA isolated from plasma were determined using the NanoString microRNA platform. MiRNAs with significant changes in expression among the KSHV-/HIV-, KSHV+/HIV-, and KSHV+/HIV+ groups were identified using the Kruskal-Wallis statistical test. MiRNAs with known tumor suppressor (supp) activity are indicated. MiRNAs with (A) or without (B) a significant changes in level of expression when comparing the groups of individuals pairwise are shown. P values indicate were calculated using a t-test.</p

KSHV associated miRNA in plasma.

<p>KSHV associated miRNA in plasma.</p

Correlation between KSHV miRNAs expression levels in plasma and KSHV viremia.

<p>Spearman correlation scatter plots showing correlations between total read counts for KSHV encoded miRNAs and KSHV plasma viremia across all the tested individuals.</p