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A key objective of bioengineering is the development of new scaffolding biomaterials with appropriate mechanical and biological properties such as strength, elasticity and biocompatibility that mimic the native host connective tissue. Here we describe the production and properties of massive synthetic elastin assemblies formed by chemically cross-linking recombinant human tropoelastin with bis(sulfosuccinimidyl) suberate, permitting the construction of elastic sponges, sheets and tubes. The innate characteristics of synthetic elastin constructs are common with those of native elastin. The Young''s Modulus ranged from 220 to 280 kPa with linearity of extension to at least 150%. Synthetic elastin was extensible by 200–370%. The constructs behaved as hydrogels and displayed stimuli-responsive characteristics towards temperature and salt concentrations. Intrinsic fluorescence spectroscopy demonstrated that the elastin fluorophore is a feature of the polypeptide. Scanning electron microscopy allowed us to construct a model of elastin assembly that was driven by the lateral association of small twisted rope-like fibrils. FT–Raman spectra at 100% strain gave amide I and III peaks that correlated with a stretch-dependent increase in α-helical content. Growth and proliferation of cells were supported in vitro while in vivo implants were well tolerated. We conclude that synthetic elastin has potential as a novel biomaterial that can be easily molded into a variety of shaped tissue substrates and has a range of properties that are required for elastic, cell-interacting and compliant applications. Furthermore, its in vitro construction provides a powerful tool to probe the early stages of elastin assembly and the molecular basis for its elasticity. [Copyright &y& Elsevier]

Presents information on a study which tested whether similarly precise localization might be achieved by phenotypic screening of the hybrids to facilitate positional cloning of unknown genes. Experimental procedures; Results and discussion.

Characterizes the common cell-surface receptor of the RD114/simian type D retroviruses. Use of retroviral cDNA library approach; Transfer and expression of cDNA; Cloning of neutral amino acid transporter; Impairment of amino acid transport due to infection of cells with retroviruses.

Mesenchymal stem cells (MSCs) have been widely investigated as a treatment for graft versus host disease (GvHD), but with mixed results. Factors such as MSC donor variability and the effects of prolonged culture expansion may have contributed to disappointing outcomes. The novel Cymerus™ manufacturing process facilitates virtually limitless production of well-defined and consistent MSCs from a single iPSC bank, using proprietary clonogenic progenitor-based technology. This avoids both inter-donor variability and the need for excessive culture expansion once MSCs are formed. This is a multi-center, open label study of Cymerus MSCs (CYP-001) in adults with steroid-resistant acute GvHD, following allogeneic hematopoietic stem cell transplantation (NCT02923375). Prior to enrolment, all subjects had failed to respond to at least three days of steroid treatment (≥1 mg/kg/day), administered in accordance with standard management at each center. Subjects received two intravenous infusions of CYP-001 one week apart, at a dose of 1 × 106 cells/kg (Cohort A) or 2 × 106 cells/kg (Cohort B), in addition to standard of care medications. The study involves follow-up over two years, with primary evaluation at 100 days. GvHD was staged and graded according to the 1994 Consensus Conference on Acute GvHD Grading. An Overall Response (OR) was defined as at least a one-grade improvement in GvHD severity, while a Complete Response (CR) was defined as the absence of any GvHD signs or symptoms. The primary objective was assessment of safety and tolerability, while the secondary objective was efficacy, based on overall survival (OS) and best responses by Day 28/Day 100. Eight subjects were enrolled per cohort, but one subject in Cohort B withdrew prior to the initiation of CYP-001 treatment. All subjects had Grade II or III GvHD at baseline. The treatment was well tolerated in all cases, and there were no treatment-related Serious Adverse Events (SAEs) reported. One patient in Cohort A died after developing pneumonia, which was not considered to be CYP-001 treatment-related. One patient in Cohort B did not show a response to CYP-001 treatment, and withdrew from the trial on Day 22 to commence palliative care. All other patients showed an OR and remained alive at Day 100. Overall, outcomes by Day 100 were similar in both cohorts, but Day 28 data suggest a faster response to the higher dose level used in Cohort B (see Table 1 and Figure 1). In conclusion, CYP-001 infusions were found to be safe and well tolerated in this study, and we believe the encouraging treatment response and overall survival rates support progression to a Phase II trial. [ABSTRACT FROM AUTHOR]

Evidence of the safety and protective benefits of human papillomavirus virus (HPV) vaccines as an anti-cancer measure is overwhelming. However, vaccine uptake varies widely across countries and falls short of levels needed to achieve population immunity. We highlight policy measures that would help ensure greater worldwide coverage and save lives. [ABSTRACT FROM AUTHOR]

Summary: Intron retention (IR) is widely recognized as a consequence of mis-splicing that leads to failed excision of intronic sequences from pre-messenger RNAs. Our bioinformatic analyses of transcriptomic and proteomic data of normal white blood cell differentiation reveal IR as a physiological mechanism of gene expression control. IR regulates the expression of 86 functionally related genes, including those that determine the nuclear shape that is unique to granulocytes. Retention of introns in specific genes is associated with downregulation of splicing factors and higher GC content. IR, conserved between human and mouse, led to reduced mRNA and protein levels by triggering the nonsense-mediated decay (NMD) pathway. In contrast to the prevalent view that NMD is limited to mRNAs encoding aberrant proteins, our data establish that IR coupled with NMD is a conserved mechanism in normal granulopoiesis. Physiological IR may provide an energetically favorable level of dynamic gene expression control prior to sustained gene translation. [ABSTRACT FROM AUTHOR]

The discovery of classic parental imprinting came, at least in part, from the analysis of transgene expression in mice . It was noticed that some transgenes were only expressed following paternal transmission and that others sometimes showed differential patterns of methylation depending on the parent of origin . Here, we present evidence of a novel and more subtle form of parental imprinting by taking advantage of the highly sensitive detection of murine transgene expression afforded by flow cytometry. We have produced nine lines of transgenic mice carrying a GFP reporter linked to the human α-globin promoter and enhancer elements, which direct expression to erythroid cells. A high proportion of transgenic lines, four of the nine, display significantly lower levels of expression following maternal transmission. Both the percentage of expressing cells and the mean fluorescence in expressing cells are between 10% and 30% lower following maternal transmission. These effects are reversible upon passage through the opposite germline. This finding raises the possibility that differences in the epigenetic state of the maternal and paternal chromosomes in adult somatic cells are more widespread than was previously thought. [Copyright &y& Elsevier]

Investigates the association of male germ-line-specific protein with epigenetic reprogramming events. Involvement of the 11-zinc-finger factor in gene regulation; Formation of methylation-sensitive insulators; Identification of the methylation marks in somatic cells.

Examines the splicing activity of ZNF265 polyclonal antibodies in the macro RNA-protein complex. Induction of an alternative splicing on the active areas of transcription; Colocalization of ZNF265 with the survival of motor neuron protein; Interaction of ZNF265 with the spliceosomal factors.

Introduction Transfusion-dependent β-thalassemia (TDT) is a severe genetic disease characterized by anemia, iron overload and serious comorbidities for which gene therapy may be an effective treatment option. LentiGlobin gene therapy contains autologous CD34+ hematopoietic stem cells (HSCs) transduced ex vivo with the BB305 lentiviral vector (LVV) encoding β-globin with a T87Q substitution. Objective Evaluate the efficacy and safety of LentiGlobin in patients with TDT in the phase 1/2 Northstar (HGB-204; NCT01745120) and phase 3 Northstar-2 (HGB-207; NCT02906202) studies. Methods Patients with TDT (≥100 mL/kg/yr of red blood cells [RBCs] or ≥8 RBC transfusions/yr) received G-CSF and plerixafor for mobilization and HSCs were transduced with the BB305 LVV. Patients underwent single agent busulfan myeloablative conditioning, were infused with transduced cells, and were followed for engraftment, safety, and efficacy. Statistics are presented as median (min – max). Results As of March 7, 2018, 18 patients (12 – 35 yrs) were treated in Northstar (follow-up 32.1 [23.1 – 41.9] months) and as of May 15, 2018, 11 patients (12 – 24 yrs) were treated in Northstar-2 (follow-up 8.5 [0.3 – 16.2] months). Patients received a median cell dose of 8.0 (5.0 – 19.4) CD34+ cells × 106/kg in both studies. The median time to neutrophil and platelet engraftment in both studies was 19 (14 – 30) days and 44 (19 – 191) days, respectively; 1 patient in Northstar-2 (0.3 months follow-up) had not engrafted at time of analysis. Of 6 patients with platelet engraftment ≥ Day 60, 4 had non-serious bleeding events prior to engraftment. All 6 had intact spleens and 3/6 received G-CSF between Days 0 – 21. Both factors appeared associated with time to platelet engraftment. In Northstar, 8/10 patients with non-β0/β0 genotypes and 2/8 patients with β0/β0 genotypes achieved transfusion independence (TI; weighted average hemoglobin [Hb] ≥ 9 g/dL without RBC transfusions for ≥ 12 months). Median Hb during TI was 10.0 (9.3 – 13.1) g/dL. In Northstar-2, 7/8 patients with non-β0/β0 genotypes and ≥ 6 months follow-up stopped RBC transfusions with Hb of 11.1 – 13.3 g/dL at last visit; the first patient treated achieved TI. Non-hematologic grade ≥ 3 adverse events post-infusion in ≥ 5/29 (15%) patients were stomatitis, febrile neutropenia, and pharyngeal inflammation. Veno-occlusive liver disease attributed to busulfan occurred in 4/29 patients (Table 1). There was no transplant-related mortality, vector-mediated replication competent lentivirus, or clonal dominance. Conclusion In Northstar, 80% of patients with non-β0/β0 genotypes achieved TI and early Northstar-2 data suggest that patients can achieve near-normal Hb without transfusions. The safety profile of LentiGlobin is consistent with myeloablative busulfan conditioning. Longer time to platelet engraftment was observed in few patients, but no graft failure or deaths were reported. [ABSTRACT FROM AUTHOR]

Simple Summary: This study provides new insights into the changing transcriptomic and epigenomic landscapes in chronic myeloid leukaemia (CML) patients who are receiving tyrosine kinase inhibitor (TKI) therapy (often life-long). Alternative splicing, vital for cellular homeostasis, is dysregulated in human cancers. Remarkably, we found abnormal splicing patterns despite molecular remission in peripheral blood cells of chronic-phase CML patients. This phenomenon is independent of the TKI drug used and in striking contrast to the normalisation of gene expression and DNA methylation patterns. Vast transcriptomics and epigenomics changes are characteristic of human cancers, including leukaemia. At remission, we assume that these changes normalise so that omics-profiles resemble those of healthy individuals. However, an in-depth transcriptomic and epigenomic analysis of cancer remission has not been undertaken. A striking exemplar of targeted remission induction occurs in chronic myeloid leukaemia (CML) following tyrosine kinase inhibitor (TKI) therapy. Using RNA sequencing and whole-genome bisulfite sequencing, we profiled samples from chronic-phase CML patients at diagnosis and remission and compared these to healthy donors. Remarkably, our analyses revealed that abnormal splicing distinguishes remission samples from normal controls. This phenomenon is independent of the TKI drug used and in striking contrast to the normalisation of gene expression and DNA methylation patterns. Most remarkable are the high intron retention (IR) levels that even exceed those observed in the diagnosis samples. Increased IR affects cell cycle regulators at diagnosis and splicing regulators at remission. We show that aberrant splicing in CML is associated with reduced expression of specific splicing factors, histone modifications and reduced DNA methylation. Our results provide novel insights into the changing transcriptomic and epigenomic landscapes of CML patients during remission. The conceptually unanticipated observation of widespread aberrant alternative splicing after remission induction warrants further exploration. These results have broad implications for studying CML relapse and treating minimal residual disease. [ABSTRACT FROM AUTHOR]