Picoliter-volume inkjet printing into planar microdevice reservoirs for low-waste, high-capacity drug loading.

Oral delivery of therapeutics is the preferred route for systemic drug administration due to ease of access and improved patient compliance. However, many therapeutics suffer from low oral bioavailability due to low pH and enzymatic conditions, poor cellular permeability, and low residence time. Microfabrication techniques have been used to create planar, asymmetric microdevices for oral drug delivery to address these limitations. The geometry of these microdevices facilitates prolonged drug exposure with unidirectional release of drug toward gastrointestinal epithelium. While these devices have significantly enhanced drug permeability in vitro and in vivo, loading drug into the micron-scale reservoirs of the devices in a low-waste, high-capacity manner remains challenging. Here, we use picoliter-volume inkjet printing to load topotecan and insulin into planar microdevices efficiently. Following a simple surface functionalization step, drug solution can be spotted into the microdevice reservoir. We show that relatively high capacities of both topotecan and insulin can be loaded into microdevices in a rapid, automated process with little to no drug waste

Fabrication of Sealed Nanostraw Microdevices for Oral Drug Delivery

The oral route is preferred for systemic drug administration and provides direct access to diseased tissue of the gastrointestinal (GI) tract. However, many drugs have poor absorption upon oral administration due to damaging enzymatic and pH conditions, mucus and cellular permeation barriers, and limited time for drug dissolution. To overcome these limitations and enhance oral drug absorption, micron-scale devices with planar, asymmetric geometries, termed microdevices, have been designed to adhere to the lining of the GI tract and release drug at high concentrations directly toward GI epithelium. Here we seal microdevices with nanostraw membranes—porous nanostructured biomolecule delivery substrates—to enhance the properties of these devices. We demonstrate that the nanostraws facilitate facile drug loading and tunable drug release, limit the influx of external molecules into the sealed drug reservoir, and increase the adhesion of devices to epithelial tissue. These findings highlight the potential of nanostraw microdevices to enhance the oral absorption of a wide range of therapeutics by binding to the lining of the GI tract, providing prolonged and proximal drug release, and reducing the exposure of their payload to drug-degrading biomolecules

Regulatory T cells promote myelin regeneration in the central nervous system

Regeneration of CNS myelin involves differentiation of oligodendrocytes from oligodendrocyte progenitor cells. In multiple sclerosis, remyelination can fail despite abundant oligodendrocyte progenitor cells, suggesting impairment of oligodendrocyte differentiation. T cells infiltrate the CNS in multiple sclerosis, yet little is known about T cell functions in remyelination. We report that regulatory T cells (T$_{reg}$) promote oligodendrocyte differentiation and (re)myelination. T$_{reg}$-deficient mice exhibited substantially impaired remyelination and oligodendrocyte differentiation, which was rescued by adoptive transfer of T$_{reg}$. In brain slice cultures, T$_{reg}$ accelerated developmental myelination and remyelination, even in the absence of overt inflammation. T$_{reg}$ directly promoted oligodendrocyte progenitor cell differentiation and myelination in vitro. We identified CCN3 as a T$_{reg}$-derived mediator of oligodendrocyte differentiation and myelination in vitro. These findings reveal a new regenerative function of T$_{reg}$ in the CNS, distinct from immunomodulation. Although the cells were originally named 'T$_{reg}$' to reflect immunoregulatory roles, this also captures emerging, regenerative T$_{reg}$ functions.This work was supported by the Biotechnology and Biological Sciences Research Council (BB/J01026X/1 and BB/N003721/1, to D.C.F.), The Leverhulme Trust (ECF-2014-390, to Y.D.), QUB (QUB - Lucy McGuigan Bequest, to D.C.F.), The UK Multiple Sclerosis Society (941 and 50, to R.J.M.F. and C.Z.), MRC UK Regenerative Medicine platform (MR/KO26666/1, to A.C.W.), University of Edinburgh Wellcome Trust Multi User Equipment Grant (WT104915MA, to A.C.W.), by a core support grant from the Wellcome Trust and MRC to the Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute (097922/Z/11/Z to R.J.M.F.), studentship support from Dept. for the Economy (Northern Ireland) and British Pathological Society, US National Multiple Sclerosis Society (RG5203A4, to J.R.C.), NIH/NINDS (NS095889, to J.R.C.), NIH/NIGMS IRACDA Postdoctoral Fellowship (K12GM081266, to S.R.M.) and Wellcome Trust (110138/Z/15/Z, to D.C.F.)

Early Ultraviolet Observations of Type IIn Supernovae Constrain the Asphericity of Their Circumstellar Material

We present a survey of the early evolution of 12 Type IIn supernovae (SNe IIn) at ultraviolet and visible light wavelengths. We use this survey to constrain the geometry of the circumstellar material (CSM) surrounding SN IIn explosions, which may shed light on their progenitor diversity. In order to distinguish between aspherical and spherical CSM, we estimate the blackbody radius temporal evolution of the SNe IIn of our sample, following the method introduced by Soumagnac et al. We find that higher-luminosity objects tend to show evidence for aspherical CSM. Depending on whether this correlation is due to physical reasons or to some selection bias, we derive a lower limit between 35% and 66% for the fraction of SNe IIn showing evidence for aspherical CSM. This result suggests that asphericity of the CSM surrounding SNe IIn is common—consistent with data from resolved images of stars undergoing considerable mass loss. It should be taken into account for more realistic modeling of these events