ItemGene Correction for SCID-X1 In Long-Term Hematopoietic Stem Cells(Nature Publishing Group) Pavel-Dinu, M.; Wiebking, V.; Dejene, B. T.; Srifa, W.; Mantri, S.; Nicolas, C. E.; Lee, C.; Bao, G.; Kildebeck, Eric J.; Punjya, N.; Sindhu, C.; Inlay, M. A.; Saxena, N.; DeRavin, S. S.; Malech, H.; Roncarolo, M. G.; Weinberg, K. I.; Porteus, M. H.; Kildebeck, Eric J.Gene correction in human long-term hematopoietic stem cells (LT-HSCs) could be an effective therapy for monogenic diseases of the blood and immune system. Here we describe an approach for X-linked sSevere cCombined iImmunodeficiency (SCID-X1) using targeted integration of a cDNA into the endogenous start codon to functionally correct disease-causing mutations throughout the gene. Using a CRISPR-Cas9/AAV6 based strategy, we achieve up to 20% targeted integration frequencies in LT-HSCs. As measures of the lack of toxicity we observe no evidence of abnormal hematopoiesis following transplantation and no evidence of off-target mutations using a high-fidelity Cas9 as a ribonucleoprotein complex. We achieve high levels of targeting frequencies (median 45%) in CD34 + HSPCs from six SCID-X1 patients and demonstrate rescue of lymphopoietic defect in a patient derived HSPC population in vitro and in vivo. In sum, our study provides specificity, toxicity and efficacy data supportive of clinical development of genome editing to treat SCID-Xl. ©2019 The Author(s). ItemEnvironmental Dynamic Mechanical Analysis to Predict the Softening Behavior of Neural Implants(NLM (Medline)) Hosseini, Seyed Mahmoud; Voit, Walter E.; Ecker, Melanie; Hosseini, Seyed Mahmoud; Voit, Walter E.; Ecker, MelanieWhen using dynamically softening substrates for neural implants, it is important to have a reliable in vitro method to characterize the softening behavior of these materials. In the past, it has not been possible to satisfactorily measure the softening of thin films under conditions mimicking body environment without substantial effort. This publication presents a new and simple method that allows dynamic mechanical analysis (DMA) of polymers in solutions, such as phosphate buffered saline (PBS), at relevant temperatures. The use of environmental DMA allows measurement of the softening effects of polymers due to plasticization in various media and temperatures, which therefore allows a prediction of the materials behavior under in vivo conditions.