Polycytidine tract deletion from microRNA-detargeted oncolytic Mengovirus optimizes the therapeutic index in a murine multiple myeloma model.

Mengovirus is an oncolytic picornavirus whose broad host range allows for testing in immunocompetent cancer models. Two pathogenicity-ablating approaches, polycytidine (polyC) tract truncation and microRNA (miRNA) targets insertion, eliminated the risk of encephalomyocarditis. To investigate whether a polyC truncated, miRNA-detargeted oncolytic Mengovirus might be boosted, we partially or fully rebuilt the polyC tract into the 5' noncoding region (NCR) of polyC-deleted (MC0) oncolytic constructs (NC) carrying miRNA target (miRT) insertions to eliminate cardiac/muscular (miR-133b and miR-208a) and neuronal (miR-124) tropisms. PolyC-reconstituted viruses (MC24-NC and MC37-NC) replicated in vitro and showed the expected tropism restrictions, but reduced cytotoxicity and miRT deletions were frequently observed. In the MPC-11 immune competent mouse plasmacytoma model, both intratumoral and systemic administration of MC0-NC led to faster tumor responses than MC24-NC or MC37-NC, with combined durable complete response rates of 75%, 0.5%, and 30%, respectively. Secondary viremia was higher following MC0-NC versus MC24-NC or MC37-NC therapy. Sequence analysis of virus progeny from treated mice revealed a high prevalence of miRT sequences loss among MC24- and MC37- viral genomes, but not in MC0-NC. Overall, MC0-NC was capable of stably retaining miRT sites and provided a more effective treatment and is therefore our lead Mengovirus candidate for clinical translation.

Does BMI Matter? A 10-Year Single Institutional Experience on 571 Bariatric Surgery Patients With BMI >50 kg/m 2.

INTRODUCTION: Patients undergoing bariatric surgery with body mass index (BMI) >50 kg/m 2 are at a higher risk of surgical morbidity when compared with less obese patients, however, there is limited data correlating surgical risk and efficacy with increasing BMI in patients with severe obesity. We hypothesize that regardless of the degree above 50 kg/m 2 their BMI, patients with severe obesity respond similarly to bariatric surgery. MATERIALS AND METHODS: We performed a retrospective analysis of patients with BMI >50 kg/m 2 who underwent biliopancreatic diversion with duodenal switch, Roux-en-Y gastric bypass, or sleeve gastrectomy at a single institution. Outcomes were compared in patients with a BMI between 50 and 60 kg/m 2 to patients with a BMI >60 kg/m 2 and included percent total weight loss as well as early and late complications. Statistical analyses were performed using logistic regression, univariate, and multivariate models. RESULTS: There were 571 patients with BMI >50 kg/m 2 who underwent bariatric surgery at our center, 170 (29.8%) had a BMI >60 kg/m 2 . Percent total weight loss was statistically significant between the BMI 50 and 60 kg/m 2 and BMI >60 kg/m 2 groups at 24 months ( P =0.047) but not at 60 months ( P =0.54). No significant difference was found in the incidence of early complications in a univariate ( P =0.46) or a multivariate ( P =0.06) analysis. The BMI >60 subgroup was associated with a higher rate of late complications in univariate analysis (heart rate=2.37; 1.03-5.47, P =0.04), but not in multivariate analysis ( P =0.78). CONCLUSIONS: Efficacy and complication rates of bariatric surgeries are similar in patients with BMI 50 to 60 kg/m 2 and >60 kg/m 2 , providing evidence supporting similar management of patients despite specific subgroups.

The Outcomes of Laparoscopic Biliopancreatic Diversion with Duodenal Switch on Gastro-esophageal Reflux Disease: the Mayo Clinic Experience.

PURPOSE: The outcomes of laparoscopic biliopancreatic diversion with duodenal switch (BPD-DS) on gastro-esophageal reflux disease (GERD) are not well elucidated. MATERIAL/METHODS: This retrospective review included patients undergoing laparoscopic primary BPD-DS at Mayo Clinic from 2009 to 2019. GERD parameters analyzed included subjective symptom report/anti-reflux medication intake and/or endoscopic findings. GERD-HRQL questionnaire was also utilized post-operatively. Three subgroups were employed to stratify patients depending on GERD outcomes: the "No-effect" subgroup included patients where surgery did not affect either positively (GERD resolution) or negatively (de novo GERD) GERD outcome, "De novo GERD" subgroup, and "GERD-resolved" subgroup. Multinomial logistic modeling was used to examine associations with the 3-level GERD subgroup (p<0.05). RESULTS: Seventy-six patients were included in the analysis. Thirty-four (44.7%) patients were found to be in the "GERD-resolved" subgroup, 28 (36.8%) patients in the "No-effect" subgroup, and 14 (18.4%) patients in the "De novo GERD" subgroup. Multinomial logistic modeling showed that patients with pre-surgery diabetes mellitus (DM) had lesser odds (OR= 0.248, (95% CI: 0.085-0.724, p=0.0108)) of GERD resolution than patients without pre-surgery DM. An association was also established between %TWL at 6 and 12 months following the procedure and GERD outcome (p=0.017 and 0.008, respectively). Finally, the mean (SD) post-operative GERD-HRQL score was 8.7 (8.1) points, and 69 (91%) patients were currently satisfied with their post-operative condition. CONCLUSION: Laparoscopic BPD-DS appears to have a satisfactory GERD outcome in most patients undergoing the operation. There appears to be an association between pre-operative DM, %TWL at 6 and 12 months, and GERD prognosis in this population.

Collateral Lethal Effects of Complementary Oncolytic Viruses.

Virus-infected cells release type 1 interferons, which induce an antiviral state in neighboring cells. Naturally occurring viruses are therefore equipped with stealth replication strategies to limit virus sensing and/or with combat strategies to prevent or reverse the antiviral state. Here we show that oncolytic viruses with simple RNA genomes whose spread was suppressed in tumor cells pretreated with interferon were able to replicate efficiently when the cells were coinfected with a poxvirus known to encode a diversity of innate immune combat proteins. In vivo the poxvirus was shown to reverse the intratumoral antiviral state, rescuing RNA virus replication in an otherwise restrictive syngeneic mouse tumor model leading to antitumor efficacy. Pairing of complementary oncolytic viruses is a promising strategy to enhance the antitumor activity of this novel class of anticancer drugs.

Complete Genome of Bacillus megaterium Podophage Pascal.

Podophage Pascal infects Bacillus megaterium, a commonly used model organism in biochemical research and an important industrial-scale protein production system. Here, we report the sequenced and annotated genome of Pascal and describe its prominent features. Bacteriophages such as Pascal may be valuable tools for research and industry.

Different roles of the three loops forming the adhesive interface of nectin-4 in measles virus binding and cell entry, nectin-4 homodimerization, and heterodimerization with nectin-1.

UNLABELLED: Many viruses utilize cell adhesion molecules of the immunoglobulin superfamily as receptors. In particular, viruses of different classes exploit nectins. The large DNA viruses, herpes simplex and pseudorabies viruses, use ubiquitous nectins 1 and 2. The negative-strand RNA virus measles virus (MeV) uses tissue-specific nectin-4, and the positive-strand RNA virus poliovirus uses nectin-like 5 (necl-5), also known as poliovirus receptor. These viruses contact the BC, C'C", and FG loops on the upper tip of their receptor's most membrane-distal domain. This location corresponds to the newly defined canonical adhesive interface of nectins, but how viruses utilize this interface has remained unclear. Here we show that the same key residues in the BC and FG loops of nectin-4 govern binding to the MeV attachment protein hemagglutinin (H) and cell entry, nectin-4 homodimerization, and heterodimerization with nectin-1. On the other hand, residues in the C'C" loop necessary for homo- and heterotypic interactions are dispensable for MeV-induced fusion and cell entry. Remarkably, the C'C" loop governs dissociation of the nectin-4 and H ectodomains. We provide formal proof that H can interfere with the formation of stable nectin-1/nectin-4 heterodimers. Finally, while developing an alternative model to study MeV spread, we observed that polarized primary pig airway epithelial sheets cannot be infected. We show that a single amino acid variant in the BC loop of pig nectin-4 fully accounts for restricted MeV entry. Thus, the three loops forming the adhesive interface of nectin-4 have different roles in supporting MeV H association and dissociation and MeV-induced fusion. IMPORTANCE: Different viruses utilize nectins as receptors. Nectins are immunoglobulin superfamily glycoproteins that mediate cell-cell adhesion in vertebrate tissues. They interact through an adhesive interface located at the top of their membrane-distal domain. How viruses utilize the three loops forming this interface has remained unclear. We demonstrate that while nectin-nectin interactions require residues in all three loops, the association of nectin-4 with the measles virus hemagglutinin requires only the BC and FG loops. However, we discovered that residues in the C'C" loop modulate the dissociation of nectin-4 from the viral hemagglutinin. Analogous mechanisms may support cell entry of other viruses that utilize nectins or other cell adhesion molecules of the immunoglobulin superfamily as receptors.

Complete Genome of Bacillus thuringiensis Myophage Spock.

Bacillus thuringiensis is a Gram-positive, sporulating soil microbe with valuable pesticide-producing properties. The study of bacteriophages of B. thuringiensis could provide new biotechnological tools for the use of this bacterium. Here, we present the complete annotated genome of Spock, a myophage of B. thuringiensis, and describe its features.