Demo Faculty

163 articles

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Sep 2022 • Nucleic Acids Research

TISMO: syngeneic mouse tumor database to model tumor immunity and immunotherapy response

Zexian Zeng, Cheryl J Wong, Lin Yang, Nofal Ouardaoui, Dian Li, Wubing Zhang, Shengqing Gu, Yi Zhang, Yang Liu, Xiaoqing Wang, Jingxin Fu, Liye Zhou, Boning Zhang, Sarah Kim, Kathleen B Yates, Myles Brown, Gordon J Freeman, Ravindra Uppaluri, Robert Manguso, X Shirley Liu

Syngeneic mouse models are tumors derived from murine cancer cells engrafted on genetically identical mouse strains. They are widely used tools for studying tumor immunity and immunotherapy response in the context of a fully functional murine immune system. Large volumes of syngeneic mouse tumor expression profiles under different immunotherapy treatments have been generated, although a lack of systematic collection and analysis makes data reuse challenging. We present Tumor Immune Syngeneic MOuse (TISMO), a database with an extensive collection of syngeneic mouse model profiles with interactive visualization features. TISMO contains 605 in vitro RNA-seq samples from 49 syngeneic cancer cell lines across 23 cancer types, of which 195 underwent cytokine treatment. TISMO also includes 1518 in vivo RNA-seq samples from 68 syngeneic mouse tumor models across 19 cancer types, of …

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May 2022 • Cytotherapy

Rapid single-cell identification of Epstein–Barr virus-specific T-cell receptors for cellular therapy

María Fernanda Lammoglia Cobo, Carlotta Welters, Leonie Rosenberger, Matthias Leisegang, Kerstin Dietze, Christian Pircher, Livius Penter, Regina Gary, Lars Bullinger, Anna Takvorian, Andreas Moosmann, Klaus Dornmair, Thomas Blankenstein, Thomas Kammertöns, Armin Gerbitz, Leo Hansmann

Background and aimsEpstein–Barr virus (EBV) is associated with solid and hematopoietic malignancies. After allogeneic stem cell transplantation, EBV infection or reactivation represents a potentially life-threatening condition with no specific treatment available in clinical routine. In vitro expansion of naturally occurring EBV-specific T cells for adoptive transfer is time-consuming and influenced by the donor's T-cell receptor (TCR) repertoire and requires a specific memory compartment that is non-existent in seronegative individuals.The authors present highly efficient identification of EBV-specific TCRs that can be expressed on human T cells and recognize EBV-infected cells.Methods and ResultsMononuclear cells from six stem cell grafts were expanded in vitro with three HLA-B*35:01- or four HLA-A*02:01-presented peptides derived from six EBV proteins expressed during latent and lytic infection. Epitope-specific …

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Apr 2022 • Clinical Cancer Research: an Official Journal of the American Association for Cancer Research

Improved T cell immunity following neoadjuvant chemotherapy in ovarian cancer.

Min Liu, Nabihah Tayob, Livius Penter, M Sellars, Anna Tarren, Vipheaviny Chea, Isabel Carulli, Teddy Huang, Shuqiang Li, Su-Chun Cheng, Phuong Le, Laura Frackiewicz, Julia Fasse, Courtney Qi, Joyce F Liu, Elizabeth H Stover, Jennifer Curtis, Kenneth J Livak, Donna Neuberg, Guang Lan Zhang, Ursula A Matulonis, Catherine J Wu, Derin B Keskin, Panagiotis A Konstantinopoulos

PurposeAlthough local tissue-based immune responses are critical for elucidating direct tumor-immune cell interactions, peripheral immune responses are increasingly recognized as occupying an important role in anti-cancer immunity. We evaluated serial blood samples from patients with epithelial ovarian cancer (EOC) undergoing standard-of-care neoadjuvant carboplatin and paclitaxel chemotherapy (including dexamethasone for prophylaxis of paclitaxel-associated hypersensitivity reactions) to characterize the evolution of the peripheral immune cell function and composition during therapy.

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Jan 2022 • Nucleic acids research

TISMO: syngeneic mouse tumor database to model tumor immunity and immunotherapy response

Zexian Zeng, Cheryl J Wong, Lin Yang, Nofal Ouardaoui, Dian Li, Wubing Zhang, Shengqing Gu, Yi Zhang, Yang Liu, Xiaoqing Wang, Jingxin Fu, Liye Zhou, Boning Zhang, Sarah Kim, Kathleen B Yates, Myles Brown, Gordon J Freeman, Ravindra Uppaluri, Robert Manguso, X Shirley Liu

Syngeneic mouse models are tumors derived from murine cancer cells engrafted on genetically identical mouse strains. They are widely used tools for studying tumor immunity and immunotherapy response in the context of a fully functional murine immune system. Large volumes of syngeneic mouse tumor expression profiles under different immunotherapy treatments have been generated, although a lack of systematic collection and analysis makes data reuse challenging. We present Tumor Immune Syngeneic MOuse (TISMO), a database with an extensive collection of syngeneic mouse model profiles with interactive visualization features. TISMO contains 605 in vitro RNA-seq samples from 49 syngeneic cancer cell lines across 23 cancer types, of which 195 underwent cytokine treatment. TISMO also includes 1518 in vivo RNA-seq samples from 68 syngeneic mouse tumor models across 19 cancer types, of …

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Jan 2022 • Journal for ImmunoTherapy of Cancer

Checkpoint blockade-induced CD8+ T cell differentiation in head and neck cancer responders

Liye Zhou, Zexian Zeng, Ann Marie Egloff, Fan Zhang, Fei Guo, Katie M Campbell, Peter Du, Jingxin Fu, Paul Zolkind, Xiaojing Ma, Zhe Zhang, Yi Zhang, Xiaoqing Wang, Shengqing Gu, Rachel Riley, Yasutaka Nakahori, Joshua Keegan, Robert Haddad, Jonathan D Schoenfeld, Obi Griffith, Robert T Manguso, James A Lederer, X Shirley Liu, Ravindra Uppaluri

Background Immune checkpoint blockade (ICB) response in recurrent/metastatic head and neck squamous cell carcinoma (HNSCC) is limited to 15%–20% of patients and underpinnings of resistance remain undefined.Methods Starting with an anti-PD1 sensitive murine HNSCC cell line, we generated an isogenic anti-PD1 resistant model. Mass cytometry was used to delineate tumor microenvironments of both sensitive parental murine oral carcinoma (MOC1) and resistant MOC1esc1 tumors. To examine heterogeneity and clonal dynamics of tumor infiltrating lymphocytes (TILs), we applied paired single-cell RNA and TCR sequencing in three HNSCC models.Results Anti-PD1 resistant MOC1esc1 line displayed a conserved cell intrinsic immune evasion signature. Immunoprofiling showed distinct baseline tumor microenvironments of MOC1 and MOC1esc1, as well as the remodeling of immune compartments on …

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Dec 2021 • Molecular Cancer Therapeutics 20 (12 Supplement), P108-P108, 2021

Abstract P108: In vivo CRISPR screens identify E3 ligase COP1 as a modulator of macrophage infiltration and cancer immunotherapy target

Xiaoqing Wang, Collin Tokheim, Shengqing S Gu, Binbin Wang, Qin Tang, Yihao Li, Nicole Traugh, Zexian Zeng, Yi Zhang, Boning Zhang, Jingxin Fu, Tengfei Xiao, Wei Li, Clifford Meyer, Peng Jiang, Paloma Cejas, Klothilda Lim, Henry Long, Myles Brown, X Shirley Liu

Despite remarkable clinical efficacies of immune checkpoint blockade (ICB) in cancer treatment, ICB benefits in triple-negative breast cancer (TNBC) remain limited. Through pooled in vivo CRISPR knockout (KO) screens in syngeneic TNBC mouse models, we found that inhibition of the E3 ubiquitin ligase COP1 in cancer cells decreases the secretion of macrophage-associated chemokines, reduces tumor macrophage infiltration, enhances tumor immunity and ICB response. Transcriptomics, epigenomics, and proteomics analyses revealed COP1 functions through proteasomal degradation of the C/ebpδ protein. COP1 substrate TRIB2 functions as a scaffold linking COP1 and C/ebpδ, which leads to polyubiquitination of C/ebpδ. COP1 inhibition stabilizes C/ebpδ to suppress the expression of macrophage chemoattractant genes. Our integrated approach implicates COP1 as a target for improving cancer …

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Nov 2021 • Journal for ImmunoTherapy of Cancer 9 (Suppl 2), 2021

700 Increasing MHC-I expression to potentiate immune checkpoint blockade therapy

Shengqing Gu, Wubing Zhang, Xiaoqing Wang, Peng Jiang, Nicole Traugh, Ziyi Li, Clifford Meyer, Blair Stewig, Yingtian Xie, Xia Bu, Michael Manos, Alba Font-Tello, Evisa Gjini, Ana Lako, Klothilda Lim, Jake Conway, Alok Tewari, Zexian Zeng, Avinash Das Sahu, Collin Tokheim, Jason Weirather, Jingxin Fu, Yi Zhang, Benjamin Kroger, Jin Hua Liang, Paloma Cejas, Gordon Freeman, Scott Rodig, Henry Long, Benjamin Gewurz, F Stephen Hodi, Myles Brown, X Shirley Liu

Background Cancer immunotherapy, especially immune checkpoint blockade (ICB) therapy, is leading to a paradigm shift in cancer treatment, as a small percentage of cancer patients have obtained durable remission following ICB treatment. Successful ICB responses rely on cancer cells presenting antigens to the cell surface via the major histocompatibility complex (MHC), which activates antigen-specific T-lymphocytes to kill cancer cells. Type-I MHC (MHC-I) is wildly expressed in all cell types and mediates the interaction with cytotoxic CD8 T cells. However, over 65% of cancer patients are estimated to show defects in MHC-I-mediated antigen presentation, including downregulation of its expression that can lead to primary or acquired resistance to ICB therapy, and therapeutic strategies to effectively restore or boost MHC-I are limited.Methods Here, we employed a CRISPR screening approach with dual-marker …

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Nov 2021 • Blood

Dissecting Richter's Syndrome in a Multiplexed CRISPR-Based Mouse Model Reveals Key Changes in MYC, Interferon and BCR Signaling Underlying Transformation

Elisa Ten Hacken, Shanye Yin, Tomasz Sewastianik, Livius Penter, Neil Ruthen, Michaela Gruber, Erin Michelle Parry, Romain Guieze, Robert A Redd, Mohamed Uduman, Shuqiang Li, Jackson Southard, Maria Hernandez-Sanchez, Salma Parvin, Fen Zhu, Gabriela Brunsting Hoffmann, Elizabeth Witten, Kenneth J Livak, Matthew S Davids, Anthony G Letai, Donna S Neuberg, Ruben D Carrasco, Catherine J Wu

Richter's syndrome (RS) represents one of the foremost challenges in CLL management, and its pathogenesis remains largely undefined. We recently leveraged CRISPR-Cas9 in vivo gene editing to develop mouse models of RS by engineering multiplexed loss-of-function lesions typical of CLL (Atm, Trp53, Chd2, Birc3, Mga, Samhd1) in early stem and progenitor cells [Lineage-Sca-1+ c-kit+(LSK)] from MDR-Cd19Cas9 donor mice. These animals express Cas9-GFP in a B-cell restricted fashion and the leukemogenic MDR lesion, which mimics del (13q) when the sgRNA-transduced LSK cells are transplanted in CD45. 1 immunocompetent recipients. Through these methods, we observed not only development of CLL, but also transformation into RS, and even captured a stage where CLL and RS were co-existing in the same animal (CLL/RS).We hypothesized that the molecular events underlying RS development …

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Nov 2021 • Blood

Mitochondrial DNA Mutations Distinguish Individual Donor-and Recipient-Derived Immune Cells Following Matched Unrelated Allogeneic Stem Cell Transplantation

Livius Penter, Jackson Southard, Shuqiang Li, Caleb A Lareau, Leif S Ludwig, Nicoletta Cieri, Alexandria Maurer, Daniel J DeAngelo, Srinika Ranasinghe, Donna S Neuberg, Vijay G Sankaran, Robert J Soiffer, Kenneth J Livak, Jacqueline S Garcia, Catherine J Wu

Reconstitution of donor hematopoiesis after allogeneic hematopoietic stem cell transplantation (HSCT) forms the basis for effective graft-versus-leukemia responses, but mixed chimerism is not an infrequent outcome. How the donor and host hematopoietic system interact under conditions of mixed chimerism remains incompletely understood. Multi-modal single cell sequencing platforms are increasingly available and provide information regarding cell identities and interactions at high resolution. However, the analysis of post-transplant immune reconstitution requires consistent distinguishing of donor-and recipient-derived cells, which for sparse single cell sequencing data until now has remained a challenge.Recently, mitochondrial DNA (mtDNA) mutations have been recognized for their potential as personal genetic barcodes that can be detected with mitochondrial single cell assay for transposase-accessible …

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Nov 2021 • Blood Advances

Coevolving JAK2V617F+relapsed AML and donor T cells with PD-1 blockade after stem cell transplantation: an index case

Livius Penter, Satyen H Gohil, Teddy Huang, Emily M Thrash, Dominik Schmidt, Shuqiang Li, Mariano Severgnini, Donna Neuberg, F Stephen Hodi, Kenneth J Livak, Robert Zeiser, Pavan Bachireddy, Catherine J Wu

Relapse of myeloproliferative neoplasms (MPNs) after allogeneic hematopoietic stem cell transplantation (HSCT) is associated with poor outcomes, as therapeutic approaches to reinstate effective graft-versus-leukemia (GVL) responses remain suboptimal. Immune escape through overexpression of PD-L1 in JAK2V617F-mutated MPN provides a rationale for therapeutic PD-1 blockade, and indeed, clinical activity of nivolumab in relapsed MPN post-HSCT has been observed. Elucidation of the features of response following PD-1 blockade in such patients could inform novel therapeutic concepts that enhance GVL. Here, we report an integrated high-dimensional analysis using single-cell RNA sequencing, T-cell receptor sequencing, cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq), and assay for transposase-accessible chromatin using sequencing (scATAC-seq), together with mass …

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Sep 2021 • Cell

In vivo CRISPR screens identify the E3 ligase Cop1 as a modulator of macrophage infiltration and cancer immunotherapy target

Xiaoqing Wang, Collin Tokheim, Shengqing Stan Gu, Binbin Wang, Qin Tang, Yihao Li, Nicole Traugh, Zexian Zeng, Yi Zhang, Ziyi Li, Boning Zhang, Jingxin Fu, Tengfei Xiao, Wei Li, Clifford A Meyer, Jun Chu, Peng Jiang, Paloma Cejas, Klothilda Lim, Henry Long, Myles Brown, X Shirley Liu

Despite remarkable clinical efficacy of immune checkpoint blockade (ICB) in cancer treatment, ICB benefits for triple-negative breast cancer (TNBC) remain limited. Through pooled in vivo CRISPR knockout (KO) screens in syngeneic TNBC mouse models, we found that deletion of the E3 ubiquitin ligase Cop1 in cancer cells decreases secretion of macrophage-associated chemokines, reduces tumor macrophage infiltration, enhances anti-tumor immunity, and strengthens ICB response. Transcriptomics, epigenomics, and proteomics analyses revealed that Cop1 functions through proteasomal degradation of the C/ebpδ protein. The Cop1 substrate Trib2 functions as a scaffold linking Cop1 and C/ebpδ, which leads to polyubiquitination of C/ebpδ. In addition, deletion of the E3 ubiquitin ligase Cop1 in cancer cells stabilizes C/ebpδ to suppress expression of macrophage chemoattractant genes. Our integrated …

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Sep 2021 • Cell

In vivo CRISPR screens identify the E3 ligase Cop1 as a modulator of macrophage infiltration and cancer immunotherapy target

Xiaoqing Wang, Collin Tokheim, Shengqing Stan Gu, Binbin Wang, Qin Tang, Yihao Li, Nicole Traugh, Zexian Zeng, Yi Zhang, Ziyi Li, Boning Zhang, Jingxin Fu, Tengfei Xiao, Wei Li, Clifford A Meyer, Jun Chu, Peng Jiang, Paloma Cejas, Klothilda Lim, Henry Long, Myles Brown, X Shirley Liu

Despite remarkable clinical efficacy of immune checkpoint blockade (ICB) in cancer treatment, ICB benefits for triple-negative breast cancer (TNBC) remain limited. Through pooled in vivo CRISPR knockout (KO) screens in syngeneic TNBC mouse models, we found that deletion of the E3 ubiquitin ligase Cop1 in cancer cells decreases secretion of macrophage-associated chemokines, reduces tumor macrophage infiltration, enhances anti-tumor immunity, and strengthens ICB response. Transcriptomics, epigenomics, and proteomics analyses revealed that Cop1 functions through proteasomal degradation of the C/ebpδ protein. The Cop1 substrate Trib2 functions as a scaffold linking Cop1 and C/ebpδ, which leads to polyubiquitination of C/ebpδ. In addition, deletion of the E3 ubiquitin ligase Cop1 in cancer cells stabilizes C/ebpδ to suppress expression of macrophage chemoattractant genes. Our integrated …

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Sep 2021 • Cell

In vivo CRISPR screens identify the E3 ligase Cop1 as a modulator of macrophage infiltration and cancer immunotherapy target

Xiaoqing Wang, Collin Tokheim, Shengqing Stan Gu, Binbin Wang, Qin Tang, Yihao Li, Nicole Traugh, Zexian Zeng, Yi Zhang, Ziyi Li, Boning Zhang, Jingxin Fu, Tengfei Xiao, Wei Li, Clifford A Meyer, Jun Chu, Peng Jiang, Paloma Cejas, Klothilda Lim, Henry Long, Myles Brown, X Shirley Liu

Despite remarkable clinical efficacy of immune checkpoint blockade (ICB) in cancer treatment, ICB benefits for triple-negative breast cancer (TNBC) remain limited. Through pooled in vivo CRISPR knockout (KO) screens in syngeneic TNBC mouse models, we found that deletion of the E3 ubiquitin ligase Cop1 in cancer cells decreases secretion of macrophage-associated chemokines, reduces tumor macrophage infiltration, enhances anti-tumor immunity, and strengthens ICB response. Transcriptomics, epigenomics, and proteomics analyses revealed that Cop1 functions through proteasomal degradation of the C/ebpδ protein. The Cop1 substrate Trib2 functions as a scaffold linking Cop1 and C/ebpδ, which leads to polyubiquitination of C/ebpδ. In addition, deletion of the E3 ubiquitin ligase Cop1 in cancer cells stabilizes C/ebpδ to suppress expression of macrophage chemoattractant genes. Our integrated …

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Aug 2021 • Blood Advances

Coevolving JAK2V617F+relapsed AML and donor T cells with PD-1 blockade after stem cell transplantation: an index case

Livius Penter, Satyen H Gohil, Teddy Huang, Emily M Thrash, Dominik Schmidt, Shuqiang Li, Mariano Severgnini, Donna Neuberg, F Stephen Hodi, Kenneth J Livak, Robert Zeiser, Pavan Bachireddy, Catherine J Wu

Relapse of myeloproliferative neoplasms (MPN) after allogeneic hematopoietic stem cell transplantation (HSCT) is associated with poor outcomes, as therapeutic approaches to reinstate effective graft-versus-leukemia (GvL) responses remain suboptimal. Immune escape through overexpression of PD-L1 in JAK2V617F mutated MPN provides a rationale for therapeutic PD-1 blockade, and indeed clinical activity of nivolumab in relapsed MPN post-HSCT has been observed. Elucidation of the features of response following PD-1 blockade in such patients could inform of novel therapeutic concepts for how to enhance GvL. Here, we report an integrated high-dimensional analysis using single cell RNA-, TCR-, CITE- and ATAC-sequencing together with mass cytometry on peripheral blood mononuclear cells collected at 6 timepoints before, during and after transient response to PD-1 blockade from an index case of …

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Jul 2021 • AACR Annual Meeting 2021, 2021

Abstract 65: Therapeutically increasing MHC-I expression potentiates immune checkpoint blockade

Shengqing Gu, Wubing Zhang, Xiaoqing Wang, Peng Jiang, Nicole Traugh, Ziyi Li, Clifford Meyer, Blair Stewig, Yingtian Xie, Xia Bu, Michael Manos, Alba Font-Tello, Evisa Gjini, Ana Lako, Klothilda Lim, Jake Conway, Alok Tewari, Zexian Zeng, Avinash Das Sahu, Collin Tokheim, Jason L. Weirather, Jingxin Fu, Yi Zhang, Benjamin Kroger, Jin Hua Liang, Paloma Cejas, Gordon J. Freeman, Scott J. Rodig, Henry Long, Benjamin E. Gewurz, F. Stephen Hodi, Myles Brown and X. Shirley Liu


Jun 2021 • Nat Methods

TRUST4: immune repertoire reconstruction from bulk and single-cell RNA-seq data

Liu XS Song L, Cohen D, Ouyang Z, Cao Y, Hu X

We introduce the TRUST4 open-source algorithm for reconstruction of immune receptor repertoires in αβ/γδ T cells and B cells from RNA-sequencing (RNA-seq) data. Compared with competing methods, TRUST4 supports both FASTQ and BAM format and is faster and more sensitive in assembling longer—even full-length—receptor repertoires. TRUST4 can also call repertoire sequences from single-cell RNA-seq (scRNA-seq) data without V (D) J enrichment, and is compatible with both SMART-seq and 5′ 10x Genomics platforms.

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Jun 2021 • Blood, The Journal of the American Society of Hematology

Molecular and cellular features of CTLA-4 blockade for relapsed myeloid malignancies after transplantation

Livius Penter, Yi Zhang, Alexandra Savell, Teddy Huang, Nicoletta Cieri, Emily M Thrash, Seunghee Kim-Schulze, Aashna Jhaveri, Jingxin Fu, Srinika Ranasinghe, Shuqiang Li, Wandi Zhang, Emma S Hathaway, Matthew Nazzaro, Haesook T Kim, Helen Chen, Magdalena Thurin, Scott J Rodig, Mariano Severgnini, Carrie Cibulskis, Stacey Gabriel, Kenneth J Livak, Corey Cutler, Joseph H Antin, Sarah Nikiforow, John Koreth, Vincent T Ho, Philippe Armand, Jerome Ritz, Howard Streicher, Donna Neuberg, F Stephen Hodi, Sacha Gnjatic, Robert J Soiffer, X Shirley Liu, Matthew S Davids, Pavan Bachireddy, Catherine J Wu

Relapsed myeloid disease after allogeneic stem cell transplantation (HSCT) remains largely incurable. We previously demonstrated the potent activity of immune checkpoint blockade in this clinical setting with ipilimumab or nivolumab. To define the molecular and cellular pathways by which CTLA-4 blockade with ipilimumab can reinvigorate an effective graft-versus-leukemia (GVL) response, we integrated transcriptomic analysis of leukemic biopsies with immunophenotypic profiling of matched peripheral blood samples collected from patients treated with ipilimumab following HSCT on the Experimental Therapeutics Clinical Trials Network 9204 trial. Response to ipilimumab was associated with transcriptomic evidence of increased local CD8+ T-cell infiltration and activation. Systemically, ipilimumab decreased naïve and increased memory T-cell populations and increased expression of markers of T-cell …

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May 2021 • Nature Machine Intelligence

Neural network architecture search with AMBER

Yi Zhang, Yang Liu, X Shirley Liu

Deep learning has been powerful in learning complex functions from data and has been applied in computer vision, natural language processing and biology. If we view the human genome as a book with three billion letters of nucleotides represented by A, C, G and T, genes and gene-controlling sequences are encoded in the book and variations in the genome can link to disease conditions. Neural network models that extract patterns from the sequences can help predict functional genomic elements and interpret genetic variations. However, the current deep learning models for genomics usually involve expert-designed neural network structures and require extensive tuning, making such models unapproachable for most other scientists. In a recent publication in Nature Machine Intelligence, Zhang and colleagues 1 present a framework called Automated Modelling for Biological Evidence-based Research …

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Apr 2021 • Neuro-oncology

Functional analysis of low-grade glioma genetic variants predicts key target genes and transcription factors

Mohith Manjunath, Jialu Yan, Yeoan Youn, Kristen L Drucker, Thomas M Kollmeyer, Andrew M McKinney, Valter Zazubovich, Yi Zhang, Joseph F Costello, Jeanette Eckel-Passow, Paul R Selvin, Robert B Jenkins, Jun S Song

Background Large-scale genome-wide association studies (GWAS) have implicated thousands of germline genetic variants in modulating individuals’ risk to various diseases, including cancer. At least 25 risk loci have been identified for low-grade gliomas (LGGs), but their molecular functions remain largely unknown. Methods We hypothesized that GWAS loci contain causal single nucleotide polymorphisms (SNPs) that reside in accessible open chromatin regions and modulate the expression of target genes by perturbing the binding affinity of transcription factors (TFs). We performed an integrative analysis of genomic and epigenomic data from The Cancer Genome Atlas and other public repositories to identify candidate causal SNPs within linkage disequilibrium blocks of LGG GWAS loci. We assessed their potential regulatory role via in silico TF binding sequence …

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Mar 2021 • Journal of vision

Lags and leads of accommodation in humans: Fact or fiction?

Vivek Labhishetty, Steven A Cholewiak, Austin Roorda, Martin S Banks

The focusing response of the human eye—accommodation—exhibits errors known as lags and leads. Lags occur when the stimulus is near and the eye appears to focus farther than the stimulus. Leads occur with far stimuli where the eye appears to focus nearer than the stimulus. We used objective and subjective measures simultaneously to determine where the eye is best focused. The objective measures were made with a wavefront sensor and an autorefractor, both of which analyze light reflected from the retina. These measures exhibited typical accommodative errors, mostly lags. The subjective measure was visual acuity, which of course depends not only on the eye’s optics but also on photoreception and neural processing of the retinal image. The subjective measure revealed much smaller errors. Acuity was maximized at or very close to the distance of the accommodative stimulus. Thus, accommodation is accurate in terms of maximizing visual performance.

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Mar 2021 • Optics Express

Optimal allocation of quantized human eye depth perception for multi-focal 3D display design

Alireza Aghasi, Barmak Heshmat, Leihao Wei, Moqian Tian

Creating immersive 3D stereoscopic, autostereoscopic, and lightfield experiences are becoming the center point of optical design of future head mounted displays and lightfield displays. However, despite the advancement in 3D and light field displays, there is no consensus on what are the necessary quantized depth levels for such emerging displays at stereoscopic or monocular modalities. Here we start from psychophysical theories and work toward defining and prioritizing quantized levels of depth that would saturate the human depth perception. We propose a general optimization framework, which locates the depth levels in a globally optimal way for band limited displays. While the original problem is computationally intractable, we manage to find a tractable reformulation as maximally covering a region of interest with a selection of hypographs corresponding to the monocular depth of field profiles. The results …

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