Efficient Magnon Injection and Detection via the Orbital Rashba Edelstein Effect

Orbital currents and accumulation provide a new avenue to boost spintronic effects in nanodevices. Here we use interconversion effects between charge current and orbital angular momentum to demonstrate a dramatic increase in the magnon spin injection and detection efficiencies in nanodevices consisting of a magnetic insulator contacted by Pt/CuOx electrodes. Moreover, we note distinct variations in efficiency for magnon spin injection and detection, indicating a disparity in the direct and inverse orbital Rashba Edelstein effect efficiencies

826. Transduction of Human Hematopoietic Stem Cells by RD114-TR-Pseudotyped Lentiviral Vectors

HIV-1-derived lentiviral vectors are efficiently pseudotyped by a chimeric envelope (RD114-TR) encoding the extracellular and transmembrane domains of the FLV RD114 glycoprotein fused to cytoplasmic tail (TR) of the MLV 4070A amphotropic glycoprotein. RD114-TR pseudotyped vectors may be concentrated by centrifugation, are resistant to complement inactivation, and are of particular interest for both ex vivo and in vivo gene therapy applications. We carried out a comparative analysis of VSV-G and RD114-TR-pseudotyped lentiviral vectors in transducing human cord blood-derived CD34+ hematopoietic stem/progenitor cells. Transduction efficiency was comparatively analysed in CD34+ cells in liquid culture, in the progeny of CD34+ clonogenic progenitors in semi-solid culture, and in the progeny of CD34+ repopulating stem cells after xeno-transplantation in NOD-SCID mice. In all cases, RD114-TR-pseudotyped vectors transduced hematopoietic cells at lower m.o.i., resulting in lower toxicity and more efficient stable transduction at comparable vector copy number per genome. Potential changes in CD34+ cells transcription profile and phenotype upon transduction with RD114-TR or VSV-G-pseudotyped vectors was investigated by Affymetrix Gene Chips microarray analysis. We found no significant difference in gene expression patterns between mock-RD114-TR and VSV-G-transduced cells. Our study show that the biology of repopulating hematopoietic stem cells and their progeny is not affected by transduction with RD114-TR-pseudotyped lentiviral vectors

Spin-orbit readout using thin films of topological insulator Sb2Te3 deposited by industrial magnetron sputtering

Driving a spin-logic circuit requires the production of a large output signal by spin-charge interconversion in spin-orbit readout devices. This should be possible by using topological insulators, which are known for their high spin-charge interconversion efficiency. However, high-quality topological insulators have so far only been obtained on a small scale, or with large scale deposition techniques which are not compatible with conventional industrial deposition processes. The nanopatterning and electrical spin injection into these materials has also proven difficult due to their fragile structure and low spin conductance. We present the fabrication of a spin-orbit readout device from the topological insulator Sb2Te3 deposited by large-scale industrial magnetron sputtering on SiO2. Despite a modification of the Sb2Te3 layer structural properties during the device nanofabrication, we measured a sizeable output voltage that can be unambiguously ascribed to a spin-charge interconversion process

CD20 and CD19 targeted vectors induce minimal activation of resting B lymphocytes

B lymphocytes are an important cell population of the immune system. However, until recently it was not possible to transduce resting B lymphocytes with retro- or lentiviral vectors, making them unsusceptible for genetic manipulations by these vectors. Lately, we demonstrated that lentiviral vectors pseudotyped with modified measles virus (MV) glycoproteins hemagglutinin, responsible for receptor recognition, and fusion protein were able to overcome this transduction block. They use either the natural MV receptors, CD46 and signaling lymphocyte activation molecule (SLAM), for cell entry (MV-LV) or the vector particles were further modified to selectively enter via the CD20 molecule, which is exclusively expressed on B lymphocytes (CD20-LV). It has been shown previously that transduction by MV-LV does not induce B lymphocyte activation. However, if this is also true for CD20-LV is still unknown. Here, we generated a vector specific for another B lymphocyte marker, CD19, and compared its ability to transduce resting B lymphocytes with CD20-LV. The vector (CD19ds-LV) was able to stably transduce unstimulated B lymphocytes, albeit with a reduced efficiency of about 10% compared to CD20-LV, which transduced about 30% of the cells. Since CD20 as well as CD19 are closely linked to the B lymphocyte activation pathway, we investigated if engagement of CD20 or CD19 molecules by the vector particles induces activating stimuli in resting B lymphocytes. Although, activation of B lymphocytes often involves calcium influx, we did not detect elevated calcium levels. However, the activation marker CD71 was substantially up-regulated upon CD20-LV transduction and most importantly, B lymphocytes transduced with CD20-LV or CD19ds-LV entered the G1b phase of cell cycle, whereas untransduced or MV-LV transduced B lymphocytes remained in G0. Hence, CD20 and CD19 targeting vectors induce activating stimuli in resting B lymphocytes, which most likely renders them susceptible for lentiviral vector transduction