Technical Advance
Abstract
Detecting, characterizing, and monitoring rare populations of cells can increase testing sensitivity, give insight into disease mechanism, and inform clinical decision making. One area that can benefit from increased resolution is management of cancers in clinical remission but with measurable residual disease (MRD) by multicolor FACS. Detecting and monitoring genomic clonal resistance to treatment in the setting of MRD is technically difficult and resource intensive due to the limited amounts of disease cells. Here, we describe limited-cell FACS sequencing (LC-FACSeq), a reproducible, highly sensitive method of characterizing clonal evolution in rare cells relevant to different types of acute and chronic leukemias. We demonstrate the utility of LC-FACSeq for broad multigene gene panels and its application for monitoring sequential acquisition of mutations conferring therapy resistance and clonal evolution in long-term ibrutinib treatment of patients with chronic lymphocytic leukemia. This technique is generalizable for monitoring of other blood and marrow infiltrating cancers.
Authors
Eileen Y. Hu, James S. Blachly, Caner Saygin, Hatice G. Ozer, Stephanie E. Workman, Arletta Lozanski, Tzyy-Jye Doong, Chi-Ling Chiang, Seema Bhat, Kerry A. Rogers, Jennifer A. Woyach, Kevin R. Coombes, Daniel Jones, Natarajan Muthusamy, Gerard Lozanski, John C. Byrd
Abstract
Depletion of CD4+ T cells during HIV-1 infection is mostly mediated by inflammatory cells via indirect but not clearly defined mechanisms. In this report we employed the single-cell RNA sequencing (scRNA-seq) technology to study HIV-induced transcriptomic change in innate immune cells in lymphoid organs. We performed scRNA-seq on hCD45+hCD3-hCD19- human leukocytes isolated from spleens of humanized NOD/Rag2-/-/γc-/- (NRG) mice transplanted with human CD34+ hematopoietic stem-progenitor cells (NRG-hu HSC mice). We identified major populations of innate immune cells including plasmacytoid dendritic cells (pDC), myeloid dendritic cells (mDC), macrophage, nature killer (NK) cells and innate lymphoid cells (ILC). HIV-1 infection significantly upregulated genes involved in type-I interferon inflammatory pathways in each of the innate immune subsets. Interestingly, we found that the TNF-related apoptosis-inducing ligand (TRAIL) was upregulated in the innate immune populations including pDC, mDC, macrophage, NK and ILC. We further demonstrated that blockade of TRAIL signaling pathway in NRG-hu HSC mice prevented HIV-1 induced CD4+ T cell depletion in vivo. In summary, we characterized HIV-induced transcriptomic changes of innate immune cells in the spleen at single-cell levels, identified the TRAIL+ innate immune cells and defined an important role of TRAIL signaling pathway in HIV-1 induced CD4+ T cell depletion in vivo.
Authors
Liang Cheng, Haisheng Yu, John A. Wrobel, Guangming Li, Peng Liu, Zhiyuan Hu, Xiao-Ning Xu, Lishan Su
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of human coronavirus disease 2019 (COVID-19), emerged in Wuhan, China in December 2019. The virus rapidly spread globally, resulting in a public-health crisis including more than 3.1 million cases and 224,000 deaths as of May 1, 2020. Here, we describe the identification and evaluation of commercially available reagents and assays for the molecular detection of SARS-CoV-2 in infected formalin fixed paraffin embedded (FFPE) cell pellets. We identified a suitable rabbit polyclonal anti-SARS-CoV spike protein antibody and a mouse monoclonal anti-SARS-CoV nucleocapsid protein (NP) antibody for cross detection of the respective SARS-CoV-2 proteins by immunohistochemistry (IHC) and immunofluorescence assay (IFA). Next, we established RNAscope in situ hybridization (ISH) to detect SARS-CoV-2 RNA. Furthermore, we established a multiplex fluorescence ISH (mFISH) to detect positive-sense SARS-CoV-2 RNA and negative-sense SARS-CoV-2 RNA (a replicative intermediate indicating viral replication). Finally, we developed a dual staining assay using IHC and ISH to detect SARS-CoV-2 antigen and RNA in the same FFPE section. These reagents and assays will accelerate COVID-19 pathogenesis studies in humans and in COVID-19 animal models.
Authors
Jun Liu, April M. Babka, Brian J. Kearney, Sheli R. Radoshitzky, Jens H. Kuhn, Xiankun Zeng
Abstract
Pancreatic islets secrete insulin from β cells and glucagon from α cells and dysregulated secretion of these hormones is a central component of diabetes. Thus, an improved understanding of the pathways governing coordinated β and α cell hormone secretion will provide insight into islet dysfunction in diabetes. However, the three-dimensional multicellular islet architecture, essential for coordinated islet function, presents experimental challenges for mechanistic studies of intracellular signaling pathways in primary islet cells. Here, we developed an integrated approach to study the function of primary human islet cells using genetically modified pseudoislets that resemble native islets across multiple parameters. Further, we developed a microperifusion system that allowed synchronous acquisition of GCaMP6f biosensor signal and hormone secretory profiles. We demonstrate the utility of this experimental approach by studying the effects of Gi and Gq GPCR pathways on insulin and glucagon secretion by expressing the designer receptors exclusively activated by designer drugs (DREADDs) hM4Di or hM3Dq. Activation of Gi signaling reduced insulin and glucagon secretion, while activation of Gq signaling stimulated glucagon secretion but had both stimulatory and inhibitory effects on insulin secretion which occur through changes in intracellular Ca2+. The experimental approach of combining pseudoislets with a microfluidic system, allowed the co-registration of intracellular signaling dynamics and hormone secretion and demonstrated differences in GPCR signaling pathways between human β and α cells.
Authors
John T. Walker, Rachana Haliyur, Heather A. Nelson, Matthew Ishahak, Gregory Poffenberger, Radhika Aramandla, Conrad Reihsmann, Joseph R. Luchsinger, Diane C. Saunders, Peng Wang, Adolfo Garcia-Ocana, Rita Bottino, Ashutosh Agarwal, Alvin C. Powers, Marcela Brissova
Abstract
In type 1 diabetes (T1D), autoimmune destruction of pancreatic β cells leads to insulin deficiency and loss of glycemic control. However, knowledge about human pancreas pathophysiology in T1D remains incomplete. To address this limitation, we established a pancreas tissue slice platform of donor organs with and without diabetes, facilitating the first live cell studies of human pancreas in T1D pathogenesis to our knowledge. We show that pancreas tissue slices from organ donors allow thorough assessment of processes critical for disease development, including insulin secretion, β cell physiology, endocrine cell morphology, and immune infiltration within the same donor organ. Using this approach, we compared detailed pathophysiological profiles for 4 pancreata from donors with T1D with 19 nondiabetic control donors. We demonstrate that β cell loss, β cell dysfunction, alterations of β cell physiology, and islet infiltration contributed differently to individual cases of T1D, allowing insight into pathophysiology and heterogeneity of T1D pathogenesis. Thus, our study demonstrates that organ donor pancreas tissue slices represent a promising and potentially novel approach in the search for successful prevention and reversal strategies of T1D.
Authors
Julia K. Panzer, Helmut Hiller, Christian M. Cohrs, Joana Almaça, Stephen J. Enos, Maria Beery, Sirlene Cechin, Denise M. Drotar, John R. Weitz, Jorge Santini, Mollie K. Huber, Mirza Muhammad Fahd Qadir, Ricardo L. Pastori, Juan Domínguez-Bendala, Edward A. Phelps, Mark A. Atkinson, Alberto Pugliese, Alejandro Caicedo, Irina Kusmartseva, Stephan Speier
Abstract
Roughly 10% of the world’s population has chronic kidney disease (CKD). In its advanced stages, CKD greatly increases the risk of hospitalization and death. Although kidney transplantation has revolutionized the care of advanced CKD, clinicians have limited ways of assessing donor kidney quality. Thus, optimal donor kidney-recipient matching can not be performed, meaning that some patients receive damaged kidneys that function poorly. Fibrosis is a form of chronic damage often present in donor kidneys that is an important predictor of future renal function. Currently, no safe, easy to perform technique exists that accurately quantifies renal fibrosis. We describe a novel photoacoustic (PA) imaging technique that directly images collagen, the principal component of fibrotic tissue. PA imaging non-invasively quantifies whole kidney fibrotic burden in mice, and cortical fibrosis in pig and human kidneys, with outstanding accuracy and speed. Remarkably, three-dimensional PA imaging exhibited sufficiently high resolution to capture intra-renal variations in collagen content. We further show that PA imaging can be performed in a setting that mimics human kidney transplantation, suggesting the potential for rapid clinical translation. Taken together, our data suggests that PA collagen imaging is a major advance in fibrosis quantification that could have widespread pre-clinical and clinical impact.
Authors
Eno Hysi, Xiaolin He, Muhannad N. Fadhel, Tianzhou Zhang, Adriana Krizova, Michael Ordon, Monica Farcas, Kenneth T. Pace, Victoria Mintsopoulos, Warren L. Lee, Michael Kolios, Darren Yuen
Abstract
Detailed spatial information of low-molecular-weight compounds distribution, especially in the brain, is crucial towards understanding their mechanism of actions. Imaging techniques that can directly visualize drugs in the brain at a high resolution will complement existing tools for drug distribution analysis. Here, we performed surface-enhanced Raman scattering (SERS) imaging using a bioorthogonal alkyne tag to visualize drugs directly in situ at a high resolution. Focusing on the selective serotonin reuptake inhibitor S-citalopram (S-Cit), which possesses a nitrile group, we substituted an alkynyl group into its structure and synthesized alkynylated S-Cit (Alk-S-Cit). The brain transitivity and the serotonin reuptake inhibition of Alk-S-Cit were not significantly different as compared to S-Cit. Alk-S-Cit was visualized in the coronal mouse brain section using SERS imaging with silver nanoparticles. Further, SERS imaging combined with fluorescence microscopy allowed Alk-S-Cit to be visualized in the adjacent neuronal membranes, and in the brain vessel and parenchyma. Thus, our multimodal imaging technique is an effective method for detecting low-molecular-weight compounds in their original tissue environment and can potentially offer additional information regarding the precise spatial distribution of such drugs.
Authors
Masato Tanuma, Atsushi Kasai, Kazuki Bando, Naoyuki Kotoku, Kazuo Harada, Masafumi Minoshima, Kosuke Higashino, Atsushi Kimishima, Masayoshi Arai, Yukio Ago, Kaoru Seiriki, Kazuya Kikuchi, Satoshi Kawata, Katsumasa Fujita, Hitoshi Hashimoto
Abstract
Cell therapy raises high hopes for better treatment of brain disorders. However, the majority of transplanted cells often die soon after transplantation and those that survive initially continue to die in the subacute phase, diminishing the impact of transplantations. In this study, we genetically modified transplanted human neural stem cells (hNSCs), from two distant embryonic SCs lines (H9 and RC17) to express one of four prosurvival factors – Hif1a, Akt1, Bcl-2, or Bcl-xl – and studied how these modifications improve short- and long-term survival of transplanted hNSCs. All genetic modifications dramatically increased survival of the transplanted hNSCs. Importantly, three out of four modifications also enhanced the exit of hNSCs from the cell cycle, thus avoiding aberrant growth of the transplants. Bcl-xl expression provided the strongest protection of transplanted cells, reducing both immediate and delayed cell death, and stimulated hNSC differentiation towards neuronal and oligodendroglial lineages. By designing hNSCs with drug-controlled expression of Bcl-xl, we demonstrated that short-term expression of a prosurvival factor can ensure the long-term survival of transplanted cells. Importantly, transplantation of Bcl-xl expressing hNSCs into mice suffering from stroke improved behavioral outcome and recovery of motor activity in mice.
Authors
Irina Korshunova, Sina Rhein, Diego García-González, Ines Stölting, Ulrich Pfisterer, Anna Barta, Oksana Dmytriyeva, Agnete Kirkeby, Markus Schwaninger, Konstantin Khodosevich
Abstract
Background. We hypothesized that dynamic perfluorinated gas magnetic resonance imaging (19F MRI) would sensitively detect mild cystic fibrosis (CF) lung. Methods. This prospective study enrolled 20 healthy volunteers and 24 stable subjects with CF, including a subgroup of subjects with normal FEV1 (>80% predicted, n = 9). Dynamic 19F MRI images were acquired during sequential breath holds while breathing perfluoropropane (PFP) and during gas wash-out. Outcomes included the fraction of lung without significant ventilation (ventilation defect percent, VDP) and time constants that described PFP wash-in and wash-out kinetics. Results. VDP values (mean ± SD) of healthy controls (3.87% ± 2.7%) were statistically different from moderate CF subjects (19.5% ± 15.5%, P = 0.001) but not from mild CF subjects (10.4% ± 9.9%, P = 0.24) . The fractional lung volume with slow gas wash-out was elevated both in subjects with mild (9.61% ± 4.87%; P = 0.0066) and moderate CF (16.01% ± 5.01%; P = 0.0002) when compared to healthy controls (3.84% ± 2.16%). Conclusion. 19F MRI detected significant ventilation abnormalities in subjects with cystic fibrosis. Assessment of gas wash-out kinetics was more sensitive to mild CF lung disease than quantitation of steady state ventilation defects making 19F MRI a potentially valuable method for the characterization of early lung disease in CF.
Authors
Jennifer L. Goralski, Sang Hun Chung, Tyler M. Glass, Agathe S. Ceppe, Esther O. Akinnagbe-Zusterzeel, Aaron T. Trimble, Richard C. Boucher, Brian J. Soher, H. Cecil Charles, Scott H. Donaldson, Yueh Z. Lee
Abstract
While gene transfer using recombinant adeno-associated viral (rAAV) vectors has shown success in some clinical trials, there remain many tissues that are not well transduced. Because of the recent success in reprogramming islet-derived cells into functional β cells in animal models, we constructed 2 highly complex barcoded replication competent capsid shuffled libraries and selected for high-transducing variants on primary human islets. We describe the generation of a chimeric AAV capsid (AAV-KP1) that facilitates transduction of primary human islet cells and human embryonic stem cell–derived β cells with up to 10-fold higher efficiency compared with previously studied best-in-class AAV vectors. Remarkably, this chimeric capsid also enabled transduction of both mouse and human hepatocytes at very high levels in a humanized chimeric mouse model, thus providing a versatile vector that has the potential to be used in both preclinical testing and human clinical trials for liver-based diseases and diabetes.
Authors
Katja Pekrun, Gustavo De Alencastro, Qing-Jun Luo, Jun Liu, Youngjin Kim, Sean Nygaard, Feorillo Galivo, Feijie Zhang, Ren Song, Matthew R. Tiffany, Jianpeng Xu, Matthias Hebrok, Markus Grompe, Mark A. Kay
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