Intravenously Administered Alphavirus Vector VA7 Eradicates Orthotopic Human Glioma Xenografts in Nude Mice

Background

VA7 is a neurotropic alphavirus vector based on an attenuated strain of Semliki Forest virus. We have previously shown that VA7 exhibits oncolytic activity against human melanoma xenografts in immunodeficient mice. The purpose of this study was to determine if intravenously administered VA7 would be effective against human glioma.

Methodology/Principal Findings

In vitro, U87, U251, and A172 human glioma cells were infected and killed by VA7-EGFP. In vivo, antiglioma activity of VA7 was tested in Balb/c nude mice using U87 cells stably expressing firefly luciferase in subcutaneous and orthotopic tumor models. Intravenously administered VA7-EGFP completely eradicated 100% of small and 50% of large subcutaneous U87Fluc tumors. A single intravenous injection of either VA7-EGFP or VA7 expressing Renilla luciferase (VA7-Rluc) into mice bearing orthotopic U87Fluc tumors caused a complete quenching of intracranial firefly bioluminescence and long-term survival in total 16 of 17 animals. In tumor-bearing mice injected with VA7-Rluc, transient intracranial and peripheral Renilla bioluminescence was observed. Virus was well tolerated and no damage to heart, liver, spleen, or brain was observed upon pathological assessment at three and ninety days post injection, despite detectable virus titers in these organs during the earlier time point.

Conclusion

VA7 vector is apathogenic and can enter and destroy brain tumors in nude mice when administered systemically. This study warrants further elucidation of the mechanism of tumor destruction and attenuation of the VA7 virus.     

Deconvoluting post-transplant immunity: cell subset-specific mapping reveals pathways for activation and expansion of memory T, monocytes and B cells

A major challenge for the field of transplantation is the lack of understanding of genomic and molecular drivers of early post-transplant immunity. The early immune response creates a complex milieu that determines the course of ensuing immune events and the ultimate outcome of the transplant. The objective of the current study was to mechanistically deconvolute the early immune response by purifying and profiling the constituent cell subsets of the peripheral blood. We employed genome-wide profiling of whole blood and purified CD4, CD8, B cells and monocytes in tandem with high-throughput laser-scanning cytometry in 10 kidney transplants sampled serially pre-transplant, 1, 2, 4, 8 and 12 weeks. Cytometry confirmed early cell subset depletion by antibody induction and immunosuppression. Multiple markers revealed the activation and proliferative expansion of CD45RO(+)CD62L(-) effector memory CD4/CD8 T cells as well as progressive activation of monocytes and B cells. Next, we mechanistically deconvoluted early post-transplant immunity by serial monitoring of whole blood using DNA microarrays. Parallel analysis of cell subset-specific gene expression revealed a unique spectrum of time-dependent changes and functional pathways. Gene expression profiling results were validated with 157 different probesets matching all 65 antigens detected by cytometry. Thus, serial blood cell monitoring reflects the profound changes in blood cell composition and immune activation early post-transplant. Each cell subset reveals distinct pathways and functional programs. These changes illuminate a complex, early phase of immunity and inflammation that includes activation and proliferative expansion of the memory effector and regulatory cells that may determine the phenotype and outcome of the kidney transplant.     

Dose-escalation of human anti-interferon-α receptor monoclonal antibody MEDI-546 in subjects with systemic sclerosis: a phase 1, multicenter,open label study

Introduction

Type I interferons (IFNs) are implicated in the pathogenesis of systemic sclerosis (SSc). MEDI-546 is an investigational human monoclonal antibody directed against the type I IFN receptor. This Phase 1 study evaluated the safety/tolerability, pharmacokinetics (PK), immunogenicity, and pharmacodynamics (PD) of single and multiple intravenous doses of MEDI-546 in adults with SSc.

Methods

Subjects (≥18 years) with SSc were enrolled in an open-label, dose-escalation study to receive single (0.1, 0.3, 1.0, 3.0, 10.0, or 20.0 mg/kg), or 4 weekly intravenous doses (0.3, 1.0, or 5.0 mg/kg/week) of MEDI-546. Subjects were followed for 12 weeks. Safety assessments included adverse events (AEs), laboratory results, and viral monitoring. Blood samples were collected from all subjects for determination of PK, presence of anti-drug antibodies (ADAs), and expression of type I IFN-inducible genes.

Results

Of 34 subjects (mean age 47.4 years), 32 completed treatment and 33 completed the study. Overall, 148 treatment-emergent AEs (TEAEs) were reported (68.9% mild, 27.7% moderate). TEAEs included one grade 1 infusion reaction (5.0 mg/kg/week multiple dose). Of 4 treatment-emergent serious AEs (skin ulcer, osteomyelitis, vertigo, and chronic myelogenous leukemia (CML)), only CML (1.0 mg/kg/week multiple dose) was considered possibly treatment-related. MEDI-546 exhibited non-linear PK at lower doses. ADAs were detected in 5 subjects; no apparent impact on PK was observed. Peak inhibition of the type I IFN signature in whole blood was achieved within 1 day and in skin after 7 days.

Conclusion

The safety/tolerability, PK, and PD profiles observed in this study support further clinical development of MEDI-546.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00930683","term_id":"NCT00930683"}}NCT00930683     

TREATMENT OF DIABETIC PATIENTS—Observations on the Use of Carbutamide and Tolbutamide

Of a group of 32 patients with diabetes, 26 had a favorable modification of the disease in response to administration of butyl-sulfonyl-urea. All but one of the patients who had good response were past the age of 38. All diabetic patients included in this group were those with little or no tendency to ketosis after cessation of insulin administration. No toxic manifestations were noted except for a slight decrease in leukocytes in one case.     

Standardized experiments in mutant mice reveal behavioural similarity on 129S5 and C57BL/6J backgrounds

Behavioural analysis of mice carrying engineered mutations is widely used to identify roles of specific genes in components of the mammalian behavioural repertoire. The reproducibility and robustness of phenotypic measures has become a concern that undermines the use of mouse genetic models for translational studies. Contributing factors include low individual study power, non‐standardized behavioural testing, failure to address confounds and differences in genetic background of mutant mice. We have examined the importance of these factors using a statistically robust approach applied to behavioural data obtained from three mouse mutations on 129S5 and C57BL/6J backgrounds generated in a standardized battery of five behavioural assays. The largest confounding effect was sampling variation, which partially masked the genetic background effect. Our observations suggest that strong interaction of mutation with genetic background in mice in innate and learned behaviours is not necessarily to be expected. We found composite measures of innate and learned behaviour were similarly impacted by mutations across backgrounds. We determined that, for frequently used group sizes, a single retest of a significant result conforming to the commonly used P < 0.05 threshold results in a reproducibility of 60% between identical experiments. Reproducibility was reduced in the presence of strain differences. We also identified a P‐value threshold that maximized reproducibility of mutant phenotypes across strains. This study illustrates the value of standardized approaches for quantitative assessment of behavioural phenotypes and highlights approaches that may improve the translational value of mouse behavioural studies.     

Behavioral Ecology of Sympatric Chimpanzees and Gorillas in Bwindi Impenetrable National Park,Uganda: Diet

Via a field study of chimpanzees (Pan troglodytes schweinfurthii) and gorillas (Gorilla gorilla beringei) in Bwindi Impenetrable National Park, Uganda, we found that their diets are seasonally similar, but diverge during lean seasons. Bwindi chimpanzees fed heavily on fruits of Ficus sp., which were largely ignored by the gorillas. Bwindi gorilla diet was overall more folivorous than chimpanzee diet, but was markedly more frugivorous than that of gorillas in the nearby Virunga Volcanoes. During 4 mo of the year Bwindi gorilla diet included more food species than that of the chimpanzees. Three factors in particular—seasonal consumption of fibrous foods by gorillas, interspecific differences in preferred fruit species, and meat consumption by chimpanzees—contributed to dietary divergence between the two species. When feeding on fruits, gorillas ate Myrianthus holstii more frequently than chimpanzees did, while chimpanzees included more figs in their annual diet. Chimpanzee diet included meat of duikers and monkeys; gorilla frequently consumed decaying wood.     

Human Mesenchymal Stem Cells Self-Renew and Differentiate According to a Deterministic Hierarchy

Background

Mesenchymal progenitor cells (MPCs) have been isolated from a variety of connective tissues, and are commonly called “mesenchymal stem cells” (MSCs). A stem cell is defined as having robust clonal self-renewal and multilineage differentiation potential. Accordingly, the term “MSC” has been criticised, as there is little data demonstrating self-renewal of definitive single-cell-derived (SCD) clonal populations from a mesenchymal cell source.

Methodology/Principal Findings

Here we show that a tractable MPC population, human umbilical cord perivascular cells (HUCPVCs), was capable of multilineage differentiation in vitro and, more importantly, contributed to rapid connective tissue healing in vivo by producing bone, cartilage and fibrous stroma. Furthermore, HUCPVCs exhibit a high clonogenic frequency, allowing us to isolate definitive SCD parent and daughter clones from mixed gender suspensions as determined by Y-chromosome fluorescent in situ hybridization.

Conclusions/Significance

Analysis of the multilineage differentiation capacity of SCD parent clones and daughter clones enabled us to formulate a new hierarchical schema for MSC self-renewal and differentiation in which a self-renewing multipotent MSC gives rise to more restricted self-renewing progenitors that gradually lose differentiation potential until a state of complete restriction to the fibroblast is reached.