Extracellular vesicles and their nucleic acids for biomarker discovery.

Extracellular vesicles (EVs) are a heterogenous population of vesicles originate from cells. EVs are found in different biofluids and carry different macromolecules, including proteins, lipids, and nucleic acids, providing a snap shot of the parental cells at the time of release. EVs have the ability to transfer molecular cargoes to other cells and can initiate different physiological and pathological processes. Mounting lines of evidence demonstrated that EVs' cargo and machinery is affected in disease states, positioning EVs as potential sources for the discovery of novel biomarkers. In this review, we demonstrate a conceptual overview of the EV field with particular focus on their nucleic acid cargoes. Current knowledge of EV subtypes, nucleic acid cargo and pathophysiological roles are outlined, with emphasis placed on advantages against competing analytes. We review the utility of EVs and their nucleic acid cargoes as biomarkers and critically assess the newly available advances in the field of EV biomarkers and high throughput technologies. Challenges to achieving the diagnostic potential of EVs, including sample handling, EV isolation, methodological considerations, and bioassay reproducibility are discussed. Future implementation of 'omics-based technologies and integration of systems biology approaches for the development of EV-based biomarkers and personalized medicine are also considered.

Introducing EbolaCheck: potential for point-of-need infectious disease diagnosis.

The 2013-2015 Ebolavirus disease humanitarian crisis has spurred the development of laboratory-free, point-of-care nucleic acid testing solutions. EbolaCheck is an international consortium of public health, academic and biotechnology industry stakeholders aiming to deliver clinical molecular diagnostic standard-of-care testing suitable for the West African milieu within 12 months. In this article, the current status of the EbolaCheck platform is discussed in the context of the current regulatory framework. Presented here are future goals to achieve differential diagnosis of hemorrhagic fever disease from <5-µl of whole blood samples or mucosal biofluids, in a single tube process, under 40 min and with minimal operator training requirements.

Genomic biomarkers for patient selection and stratification: the cancer paradigm.

The revolution in disease diagnosis and treatment promised on the completion of the human genome project over a decade ago has materialized in the form of unified drug and biomarker discovery and development pipelines. This strategic shift has been principally catalyzed through success stories in the field of oncology, ushering in the era of personalized medicine. Thus, a number of molecular targets have also been demonstrated to be reliable markers for selecting patients wherein treatment can be efficacious. Perhaps more importantly, however, the late adoption of biomarker strategies has also rescued drug candidates from complete late-stage failure. This review examines the historical lessons of key challenges in translating biomarker assay information into strategic and clinically actionable decisions and assesses the impact of personalized genome sequencing in the future of companion diagnostic development and commercialization.

Relevance of systems pharmacology in drug discovery.

The pharmaceutical industry is in the process of re-inventing its pipeline in an attempt to overcome its increasing phase II and III attrition rates. Here, we describe how systems pharmacology can be used as a risk assessment tool to alleviate this problem before bringing in larger investments. We propose that this translational research tool could provide a valuable, complementary addition to other emerging innovative approaches for target identification and validation in discovery and, ultimately, for aiding clinical trial optimization.

Lung delivery studies using siRNA conjugated to TAT(48-60) and penetratin reveal peptide induced reduction in gene expression and induction of innate immunity.

The therapeutic application of siRNA shows promise as an alternative approach to small-molecule inhibitors for the treatment of human disease. However, the major obstacle to its use has been the difficulty in delivering these large anionic molecules in vivo. In this study, we have investigated whether siRNA-mediated knockdown of p38 MAP kinase mRNA in mouse lung is influenced by conjugation to the nonviral delivery vector cholesterol and the cell penetrating peptides (CPP) TAT(48-60) and penetratin. Initial studies in the mouse fibroblast L929 cell line showed that siRNA conjugated to cholesterol, TAT(48-60), and penetratin, but not siRNA alone, achieved a limited reduction of p38 MAP kinase mRNA expression. Intratracheal administration of siRNA resulted in localization within macrophages and scattered epithelial cells and produced a 30-45% knockdown of p38 MAP kinase mRNA at 6 h. As with increasing doses of siRNA, conjugation to cholesterol improved upon the duration but not the magnitude of mRNA knockdown, while penetratin and TAT(48-60) had no effect. Importantly, administration of the penetratin or TAT(48-60) peptides alone caused significant reduction in p38 MAP kinase mRNA expression, while the penetratin-siRNA conjugate activated the innate immune response. Overall, these studies suggest that conjugation to cholesterol may extend but not increase siRNA-mediated p38 MAP kinase mRNA knockdown in the lung. Furthermore, the use of CPP may be limited due to as yet uncharacterized effects upon gene expression and a potential for immune activation.