Background-Two types of cells are cultured from the human peripheral blood, early endothelial progenitor cells (EPCs) and outgrowth endothelial cells (OECs), as previously reported. Here, we further characterize these cells, especially with respect to their different origins and functions both in vitro and in vivo. We also investigated whether the combination of these different cell types shows synergism during neovascularization. Methods and Results-Early EPCs were heterogeneously made up of both CD14ϩ monocyte-derived cells, which secrete cytokines, and CD14Ϫ -derived cells, which contain high levels of CD34 ϩ KDR ϩ cells. OECs were cultured almost exclusively from CD14 Ϫ cells, not CD14 ϩ cells, and were distinct from mature endothelial cells in terms of proliferation potential, KDR ϩ expression level, and telomerase activity. A portion of cells from CD14 Ϫ cells and early EPCs produced rapidly proliferating, capillary-forming cells in both the Matrigel plug and the ischemic hind limb similar to OECs. Early EPCs and OECs expressed receptors for vascular endothelial growth factor and interleukin-8, cytokines secreted by early EPCs. There was a differential increase in matrix metalloproteinases (MMPs): MMP-9 in early EPCs and MMP-2 in OECs. In vitro, the angiogenic capability of the 2 cell types was augmented by mutual interaction through cytokines and MMPs. Injection of a mixture of the 2 cells resulted in superior neovascularization in vivo to any single-cell-type transplantation. Conclusions-Distinct origins of the different types of EPCs exist that have different functions in neovascularization.Mixed transplantation of these cells results in synergistic neovascularization through cytokines and MMPs.

This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or "nanofluids," was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band ͑Ϯ10% or less͒ about the sample average with only few outliers. The thermal conductivity of the nanofluids was found to increase with particle concentration and aspect ratio, as expected from classical theory. There are ͑small͒ systematic differences in the absolute values of the nanofluid thermal conductivity among the various experimental approaches; however, such differences tend to disappear when the data are normalized to the measured thermal conductivity of the basefluid. The effective medium theory developed for dispersed particles by Maxwell in 1881 and recently generalized by Nan et al. ͓J. Appl. Phys. 81, 6692 ͑1997͔͒, was found to be in good agreement with the experimental data, suggesting that no anomalous enhancement of thermal conductivity was achieved in the nanofluids tested in this exercise.

Secretion of extracellular vesicles is a general cellular activity that spans the range from simple unicellular organisms (e.g. archaea; Gram-positive and Gram-negative bacteria) to complex multicellular ones, suggesting that this extracellular vesicle-mediated communication is evolutionarily conserved. Extracellular vesicles are spherical bilayered proteolipids with a mean diameter of 20–1,000 nm, which are known to contain various bioactive molecules including proteins, lipids, and nucleic acids. Here, we present EVpedia, which is an integrated database of high-throughput datasets from prokaryotic and eukaryotic extracellular vesicles. EVpedia provides high-throughput datasets of vesicular components (proteins, mRNAs, miRNAs, and lipids) present on prokaryotic, non-mammalian eukaryotic, and mammalian extracellular vesicles. In addition, EVpedia also provides an array of tools, such as the search and browse of vesicular components, Gene Ontology enrichment analysis, network analysis of vesicular proteins and mRNAs, and a comparison of vesicular datasets by ortholog identification. Moreover, publications on extracellular vesicle studies are listed in the database. This free web-based database of EVpedia (http://evpedia.info) might serve as a fundamental repository to stimulate the advancement of extracellular vesicle studies and to elucidate the novel functions of these complex extracellular organelles.

Gram-negative bacteria actively secrete outer membrane vesicles, spherical nano-meter-sized proteolipids enriched with outer membrane proteins, to the surroundings. Outer membrane vesicles have gained wide interests as non-living complex vaccines or delivery vehicles. However, no study has used outer membrane vesicles in treating cancer thus far. Here we investigate the potential of bacterial outer membrane vesicles as therapeutic agents to treat cancer via immunotherapy. Our results show remarkable capability of bacterial outer membrane vesicles to effectively induce long-term antitumor immune responses that can fully eradicate established tumors without notable adverse effects. Moreover, systematically administered bacterial outer membrane vesicles specifically target and accumulate in the tumor tissue, and subsequently induce the production of antitumor cytokines CXCL10 and interferon-γ. This antitumor effect is interferon-γ dependent, as interferon-γ-deficient mice could not induce such outer membrane vesicle-mediated immune response. Together, our results herein demonstrate the potential of bacterial outer membrane vesicles as effective immunotherapeutic agent that can treat various cancers without apparent adverse effects.