Biological Phenomena, Cell Phenomena, and Immunity Commons^™

Bcl-2 Inhibition Combined With Pparα Activation Synergistically Targets Leukemic Stem Cell-Like Cells In Acute Myeloid Leukemia, Chendi Xie, Hui Zhou, Dongmei Qin, Huijian Zheng, Yuanfang Tang, Wenjuan Li, Jie Zhou, Long Liu, Xinxin Yu, Hongpeng Duan, Yong Zhou, Zhifeng Li, Zhihong Fang, Yiming Luo, Bing Z Carter, Bing Xu, Jie Zha

Faculty, Staff and Student Publications

Persistence of leukemic stem cells (LSCs) is one of the determining factors to acute myeloid leukemia (AML) treatment failure and responsible for the poor prognosis of the disease. Hence, novel therapeutic strategies that target LSCs are crucial for treatment success. We investigated if targeting Bcl-2 and peroxisome proliferator activated receptor α (PPARα), two distinct cell survival regulating mechanisms could eliminate LSCs. This study demonstrate that the Bcl-2 inhibitor venetoclax combined with the PPARα agonist chiglitazar resulted in synergistic killing of LSC-like cell lines and CD34+ primary AML cells while sparing their normal counterparts. Furthermore, the combination regimen significantly suppressed AML …

Delayed Skeletal Development And Igf-1 Deficiency In A Mouse Model Of Lysinuric Protein Intolerance, Bridget M Stroup, Xiaohui Li, Sara Ho, Haonan Zhouyao, Yuqing Chen, Safa Ani, Brian Dawson, Zixue Jin, Ronit Marom, Ming-Ming Jiang, Isabel Lorenzo, Daniel Rosen, Denise Lanza, Nathalie Aceves, Sara Koh, John R Seavitt, Jason D Heaney, Brendan Lee, Lindsay C Burrage

Faculty, Staff and Students Publications

SLC7A7 deficiency, or lysinuric protein intolerance (LPI), causes loss of function of the y+LAT1 transporter critical for efflux of arginine, lysine and ornithine in certain cells. LPI is characterized by urea cycle dysfunction, renal disease, immune dysregulation, growth failure, delayed bone age and osteoporosis. We previously reported that Slc7a7 knockout mice (C57BL/6×129/SvEv F2) recapitulate LPI phenotypes, including growth failure. Our main objective in this study was to characterize the skeletal phenotype in these mice. Compared to wild-type littermates, juvenile Slc7a7 knockout mice demonstrated 70% lower body weights, 87% lower plasma IGF-1 concentrations and delayed skeletal development. Because poor survival prevents …

Why Animal Experiments Are Still Indispensable In Bone Research: A Statement By The European Calcified Tissue Society, Merle Stein, Florent Elefteriou, Björn Busse, Imke Ak Fiedler, Ronald Young Kwon, Eric Farrell, Mubashir Ahmad, Anita Ignatius, Liam Grover, Liesbet Geris, Jan Tuckermann

Faculty, Staff and Students Publications

Major achievements in bone research have always relied on animal models and in vitro systems derived from patient and animal material. However, the use of animals in research has drawn intense ethical debate and the complete abolition of animal experimentation is demanded by fractions of the population. This phenomenon is enhanced by the reproducibility crisis in science and the advance of in vitro and in silico techniques. 3D culture, organ-on-a-chip, and computer models have improved enormously over the last years. Nevertheless, the overall complexity of bone tissue-cross talk and the systemic and local regulation of bone physiology can often only …

In Vivo Gene Delivery Into Mouse Mammary Epithelial Cells Through Mammary Intraductal Injection, Wen Bu, Yi Li

Faculty, Staff and Students Publications

Mouse mammary glands comprise ductal trees, which are lined by epithelial cells and have one opening at the tip of each nipple. The epithelial cells play a major role in mammary gland function and are the origin of most mammary tumors. Introducing genes of interest into mouse mammary epithelial cells is a critical step in evaluating gene function in epithelial cells and generating mouse mammary tumor models. This goal can be accomplished through the intraductal injection of a viral vector carrying the genes of interest into the mouse mammary ductal tree. The injected virus subsequently infects mammary epithelial cells, bringing …

Antisense Oligonucleotide Therapy Rescues Disturbed Brain Rhythms And Sleep In Juvenile And Adult Mouse Models Of Angelman Syndrome, Dongwon Lee, Wu Chen, Heet Naresh Kaku, Xinming Zhuo, Eugene S Chao, Armand Soriano, Allen Kuncheria, Stephanie Flores, Joo Hyun Kim, Armando Rivera, Frank Rigo, Paymaan Jafar-Nejad, Arthur L Beaudet, Matthew S Caudill, Mingshan Xue

Faculty, Staff and Students Publications

UBE3A encodes ubiquitin protein ligase E3A, and in neurons its expression from the paternal allele is repressed by the UBE3A antisense transcript (UBE3A-ATS). This leaves neurons susceptible to loss-of-function of maternal UBE3A. Indeed, Angelman syndrome, a severe neurodevelopmental disorder, is caused by maternal UBE3A deficiency. A promising therapeutic approach to treating Angelman syndrome is to reactivate the intact paternal UBE3A by suppressing UBE3A-ATS. Prior studies show that many neurological phenotypes of maternal Ube3a knockout mice can only be rescued by reinstating Ube3a expression in early development, indicating a restricted therapeutic window for Angelman syndrome. Here, we …

Evolutionary Aspects Of Infections: Inflammation And Sickness Behaviors, Robert Dantzer

Faculty, Staff and Student Publications

Sickness behavior was conceptualized initially as the behavioral counterpart of the fever response to infectious pathogens. It helps to raise body temperature to its higher setpoint and to maintain it at this new level and it has the additional benefit of enabling a weakened organism to protect itself from other dangers. The discovery of the behavioral effects of proinflammatory cytokines produced by activated immune cells provided a cellular and molecular basis to this phenomenon. The administration of cytokines or cytokine inducers like lipopolysaccharide to healthy rodents allowed to reveal the similarities and differences between inflammation-induced sickness behavior and the fever …

Metabolome And Microbiome Multi-Omics Integration From A Murine Lung Inflammation Model Of Bronchopulmonary Dysplasia, Ahmed El Saie, Chenlian Fu, Sandra L Grimm, Matthew J Robertson, Kristi Hoffman, Vasanta Putluri, Chandra Shekar R Ambati, Nagireddy Putluri, Binoy Shivanna, Cristian Coarfa, Mohan Pammi

Faculty, Staff and Students Publications

BACKGROUND: Respiratory tract microbial dysbiosis can exacerbate inflammation and conversely inflammation may cause dysbiosis. Dysbiotic microbiome metabolites may lead to bronchopulmonary dysplasia (BPD). Hyperoxia and lipopolysaccharide (LPS) interaction alters lung microbiome and metabolome, mediating BPD lung injury sequence.

METHODS: C57BL6/J mice were exposed to 21% (normoxia) or 70% (hyperoxia) oxygen during postnatal days (PND) 1-14. Pups were injected with LPS (6 mg/kg) or equal PBS volume, intraperitoneally on PND 3, 5, and 7. At PND14, the lungs were collected for microbiome and metabolomic analyses (n = 5/group).

RESULTS: Microbiome alpha and beta diversity were similar between groups. Metabolic changes included …

Renin-Angiotensin System In Huntington's Disease: Evidence From Animal Models And Human Patients, Lucas M Kangussu, Natalia P Rocha, Priscila A C Valadão, Thatiane C G Machado, Kívia B Soares, Julliane V Joviano-Santos, Leigh B Latham, Gabriela D Colpo, Ana Flávia Almeida-Santos, Erin Furr Stimming, Ana Cristina Simões E Silva, Antônio L Teixeira, Aline Silva Miranda, Cristina Guatimosim

Faculty, Staff and Student Publications

The Renin-Angiotensin System (RAS) is expressed in the central nervous system and has important functions that go beyond blood pressure regulation. Clinical and experimental studies have suggested that alterations in the brain RAS contribute to the development and progression of neurodegenerative diseases. However, there is limited information regarding the involvement of RAS components in Huntington's disease (HD). Herein, we used the HD murine model, (BACHD), as well as samples from patients with HD to investigate the role of both the classical and alternative axes of RAS in HD pathophysiology. BACHD mice displayed worse motor performance in different behavioral tests alongside …

A Role For Insulin-Like Growth Factor 1 In The Generation Of Epileptic Spasms In A Murine Model, Carlos J Ballester-Rosado, John T Le, Trang T Lam, Carrie A Mohila, Sandi Lam, Anne E Anderson, James D Frost, John W Swann

Faculty, Staff and Students Publications

Objective: Infantile spasms are associated with a wide variety of clinical conditions, including perinatal brain injuries. We have created a model in which prolonged infusion of tetrodotoxin (TTX) into the neocortex, beginning in infancy, produces a localized lesion and reproduces the behavioral spasms, electroencephalogram (EEG) abnormalities, and drug responsiveness seen clinically. Here, we undertook experiments to explore the possibility that the growth factor IGF-1 plays a role in generating epileptic spasms.

Methods: We combined long-term video EEG recordings with quantitative immunohistochemical and biochemical analyses to unravel IGF-1's role in spasm generation. Immunohistochemistry was undertaken in surgically resected tissue from infantile …

Impaired Gate16-Mediated Exocytosis In Exocrine Tissues Causes Sjögren’S Syndrome-Like Exocrinopathy, Akiko Suzuki, Chihiro Iwaya, Kenichi Ogata, Hiroki Yoshioka, Junbo Shim, Isei Tanida, Masaaki Komatsu, Norihiro Tada, Junichi Iwata

Faculty, Staff and Student Publications

Sjögren's syndrome (SjS) is a chronic autoimmune disease characterized by immune cell infiltration of the exocrine glands, mainly the salivary and lacrimal glands. Despite recent advances in the clinical and mechanistic characterization of the disease, its etiology remains largely unknown. Here, we report that mice with a deficiency for either Atg7 or Atg3, which are enzymes involved in the ubiquitin modification pathway, in the salivary glands exhibit a SjS-like phenotype, characterized by immune cell infiltration with autoantibody detection, acinar cell death, and dry mouth. Prior to the onset of the SjS-like phenotype in these null mice, we detected an accumulation …

Concerted Type I Interferon Signaling In Microglia And Neural Cells Promotes Memory Impairment Associated With Amyloid Β Plaques, Ethan R Roy, Gabriel Chiu, Sanming Li, Nicholas E Propson, Rupa Kanchi, Baiping Wang, Cristian Coarfa, Hui Zheng, Wei Cao

Faculty, Staff and Students Publications

The principal signals that drive memory and cognitive impairment in Alzheimer's disease (AD) remain elusive. Here, we revealed brain-wide cellular reactions to type I interferon (IFN-I), an innate immune cytokine aberrantly elicited by amyloid β plaques, and examined their role in cognition and neuropathology relevant to AD in a murine amyloidosis model. Using a fate-mapping reporter system to track cellular responses to IFN-I, we detected robust, Aβ-pathology-dependent IFN-I activation in microglia and other cell types. Long-term blockade of IFN-I receptor (IFNAR) rescued both memory and synaptic deficits and resulted in reduced microgliosis, inflammation, and neuritic pathology. Microglia-specific Ifnar1 deletion attenuated …

Reduction Of Mutant Atxn1 Rescues Premature Death In A Conditional Sca1 Mouse Model, James P Orengo, Larissa Nitschke, Meike E Van Der Heijden, Nicholas A Ciaburri, Harry T Orr, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

Spinocerebellar ataxia type 1 (SCA1) is an adult-onset neurodegenerative disorder. As disease progresses, motor neurons are affected, and their dysfunction contributes toward the inability to maintain proper respiratory function, a major driving force for premature death in SCA1. To investigate the isolated role of motor neurons in SCA1, we created a conditional SCA1 (cSCA1) mouse model. This model suppresses expression of the pathogenic SCA1 allele with a floxed stop cassette. cSCA1 mice crossed to a ubiquitous Cre line recapitulate all the major features of the original SCA1 mouse model; however, they took twice as long to develop. We found that …

Ezh2 And Endometrial Cancer Development: Insights From A Mouse Model, Xin Fang, Nan Ni, Xiaofang Wang, Yanan Tian, Ivan Ivanov, Monique Rijnkels, Kayla J Bayless, John P Lydon, Qinglei Li

Faculty, Staff and Students Publications

Enhancer of zeste homolog 2 (EZH2), a core component of polycomb repressive complex 2, plays an important role in cancer development. As both oncogenic and tumor suppressive functions of EZH2 have been documented in the literature, the objective of this study is to determine the impact of Ezh2 deletion on the development and progression of endometrial cancer induced by inactivation of phosphatase and tensin homolog (PTEN), a tumor suppressor gene frequently dysregulated in endometrial cancer patients. To this end, we created mice harboring uterine deletion of both Ezh2 and Pten using Cre recombinase driven by the progesterone receptor …

Regulation Of The Double-Stranded Rna Response Through Adar1 Licenses Metaplastic Reprogramming In Gastric Epithelium, José B Sáenz, Nancy Vargas, Charles J Cho, Jason C Mills

Faculty, Staff and Students Publications

Cells recognize both foreign and host-derived double-stranded RNA (dsRNA) via a signaling pathway that is usually studied in the context of viral infection. It has become increasingly clear that the sensing and handling of endogenous dsRNA is also critical for cellular differentiation and development. The adenosine RNA deaminase, ADAR1, has been implicated as a central regulator of the dsRNA response, but how regulation of the dsRNA response might mediate cell fate during injury and whether such signaling is cell intrinsic remain unclear. Here, we show that the ADAR1-mediated response to dsRNA was dramatically induced in 2 distinct injury models of …

K-Ras And P53 Mouse Model With Molecular Characteristics Of Human Rhabdomyosarcoma And Translational Applications, Kengo Nakahata, Brian W Simons, Enrico Pozzo, Ryan Shuck, Lyazat Kurenbekova, Zachary Prudowsky, Kshiti Dholakia, Cristian Coarfa, Tajhal D Patel, Lawrence A Donehower, Jason T Yustein

Faculty, Staff and Students Publications

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children, with overall long-term survival rates of ∼65-70%. Thus, additional molecular insights and representative models are critical for identifying and evaluating new treatment modalities. Using MyoD-Cre-mediated introduction of mutant K-RasG12D and perturbations in p53, we developed a novel genetically engineered mouse model (GEMM) for RMS. The anatomic sites of primary RMS development recapitulated human disease, including tumors in the head, neck, extremities and abdomen. We confirmed RMS histology and diagnosis through Hematoxylin and Eosin staining, and positive immunohistochemical staining for desmin, myogenin, and phosphotungstic acid-Hematoxylin. Cell lines from GEMM tumors …

Super-Resolution Microscopy Reveals Photoreceptor-Specific Subciliary Location And Function Of Ciliopathy-Associated Protein Cep290, Valencia L Potter, Abigail R Moye, Michael A Robichaux, Theodore G Wensel

Faculty, Staff and Students Publications

Mutations in the cilium-associated protein CEP290 cause retinal degeneration as part of multiorgan ciliopathies or as retina-specific diseases. The precise location and the functional roles of CEP290 within cilia and, specifically, the connecting cilia (CC) of photoreceptors, remain unclear. We used super-resolution fluorescence microscopy and electron microscopy to localize CEP290 in the CC and in the primary cilia of cultured cells with subdiffraction resolution and to determine effects of CEP290 deficiency in 3 mutant models. Radially, CEP290 localizes in close proximity to the microtubule doublets in the region between the doublets and the ciliary membrane. Longitudinally, it is distributed throughout …

Exogenous Inter-Α Inhibitor Proteins Prevent Cell Death And Improve Ischemic Stroke Outcomes In Mice, Louise D Mccullough, Meaghan Roy-O'Reilly, Yun-Ju Lai, Anthony Patrizz, Yan Xu, Juneyoung Lee, Aleah Holmes, Daniel C Kraushaar, Anjali Chauhan, Lauren H Sansing, Barbara S Stonestreet, Liang Zhu, Julia Kofler, Yow-Pin Lim, Venugopal Reddy Venna

Faculty, Staff and Students Publications

Inter-α inhibitor proteins (IAIPs) are a family of endogenous plasma and extracellular matrix molecules. IAIPs suppress proinflammatory cytokines, limit excess complement activation, and bind extracellular histones to form IAIP-histone complexes, leading to neutralization of histone-associated cytotoxicity in models of sepsis. Many of these detrimental processes also play critical roles in the pathophysiology of ischemic stroke. In this study, we first assessed the clinical relevance of IAIPs in stroke and then tested the therapeutic efficacy of exogenous IAIPs in several experimental stroke models. IAIP levels were reduced in both ischemic stroke patients and in mice subjected to experimental ischemic stroke when …

Gene Therapy Knockdown Of Hippo Signaling Induces Cardiomyocyte Renewal In Pigs After Myocardial Infarction, Shijie Liu, Ke Li, Leonardo Wagner Florencio, Li Tang, Todd R Heallen, John P Leach, Yidan Wang, Francisco Grisanti, James T Willerson, Emerson C Perin, Sui Zhang, James F Martin

Faculty, Staff and Students Publications

Human heart failure, a leading cause of death worldwide, is a prominent example of a chronic disease that may result from poor cell renewal. The Hippo signaling pathway is an inhibitory kinase cascade that represses adult heart muscle cell (cardiomyocyte) proliferation and renewal after myocardial infarction in genetically modified mice. Here, we investigated an adeno-associated virus 9 (AAV9)–based gene therapy to locally knock down the Hippo pathway gene Salvador (Sav) in border zone cardiomyocytes in a pig model of ischemia/reperfusion-induced myocardial infarction. Two weeks after myocardial infarction, when pigs had left ventricular systolic dysfunction, we administered AAV9-Sav …