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Karla AR, Pinard A, Boerio ML, Hemelsoet D, Tavernier SJ, De Pauw M, Vereecke E, Fraser S, Bamshad MJ, Guo D, Callewaert B, Milewicz DM. SAMHD1 compound heterozygous rare variants associated with moyamoya and mitral valve disease in the absence of other features of Aicardi-Goutières syndrome. Am J Med Genet A 2024; 194:e63486. [PMID: 38041217 DOI: 10.1002/ajmg.a.63486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 11/10/2023] [Accepted: 11/17/2023] [Indexed: 12/03/2023]
Abstract
Aicardi-Goutières syndrome (AGS) is an autosomal recessive inflammatory syndrome that manifests as an early-onset encephalopathy with both neurologic and extraneurologic clinical findings. AGS has been associated with pathogenic variants in nine genes: TREX1, RNASEH2B, RNASEH2C, RNASEH2A, SAMHD1, ADAR, IFIH1, LSM11, and RNU7-1. Diagnosis is established by clinical findings (encephalopathy and acquired microcephaly, intellectual and physical impairments, dystonia, hepatosplenomegaly, sterile pyrexia, and/or chilblains), characteristic abnormalities on cranial CT (calcification of the basal ganglia and white matter) and MRI (leukodystrophic changes), or the identification of pathogenic/likely pathogenic variants in the known genes. One of the genes associated with AGS, SAMHD1, has also been associated with a spectrum of cerebrovascular diseases, including moyamoya disease (MMD). In this report, we describe a 31-year-old male referred to genetics for MMD since childhood who lacked the hallmark features of AGS patients but was found to have compound heterozygous SAMHD1 variants. He later developed mitral valve insufficiency due to recurrent chordal rupture and ultimately underwent a heart transplant at 37 years of age. Thus, these data suggest that SAMHD1 pathogenic variants can cause MMD without typical AGS symptoms and support that SAMHD1 should be assessed in MMD patients even in the absence of AGS features.
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Affiliation(s)
- Aamuktha R Karla
- Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Amélie Pinard
- Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Maura L Boerio
- Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | | | - Simon J Tavernier
- Department of Internal Medicine and Pediatrics, Center for Primary Immunodeficiency, Jeffrey Modell Diagnosis and Research Center, Ghent University Hospital, Ghent, Belgium
| | - Michel De Pauw
- Department of Cardiology, Ghent University Hospital, Ghent, Belgium
| | - Elke Vereecke
- Department of Radiology, Ghent University Hospital, Ghent, Belgium
| | - Stuart Fraser
- Division of Child Neurology, Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Michael J Bamshad
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, Washington, USA
| | - Dongchuan Guo
- Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Bert Callewaert
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Dianna M Milewicz
- Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
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2
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Booth N, Ngwube A, Appavu B, Shah S, Abruzzo T. Reversal of Cerebral Arteriopathy Post-Hematopoietic Stem Cell Transplant for Sickle Cell Disease. Pediatrics 2024; 153:e2023062643. [PMID: 38263886 DOI: 10.1542/peds.2023-062643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/01/2023] [Indexed: 01/25/2024] Open
Abstract
Sickle cell disease (SCD) is a chronic hematologic disorder which causes progressive cerebral arteriopathy beginning in childhood. As a result, arterial ischemic stroke is a major cause of morbidity and mortality in SCD, and SCD is a leading cause of childhood stroke worldwide. Allogenic hematopoietic stem cell transplant (HSCT) may be curative for individuals with SCD. Long-term outcomes and effects are currently being studied. In this report, we describe a child with SCD who presented with arterial ischemic stroke at 6 years of age and was found to have a severe form of cerebral large vessel arteriopathy by catheter-directed angiography. The patient initially underwent revascularization surgery by indirect superficial temporal artery to middle cerebral artery bypass, and 1 year later, he underwent curative HSCT. Approximately 3 years after HSCT, repeat catheter-directed angiography revealed a striking reversal of cerebral large vessel arteriopathy. This article reveals a previously unrecognized and potentially beneficial effect of HSCT that may ameliorate cerebral large vessel arteriopathy and improve cerebrovascular health for children with SCD.
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Affiliation(s)
- Natalie Booth
- Cancer and Blood Disorders Institute, Johns Hopkins All Children's Hospital, St Petersburg, FL
| | - Alexander Ngwube
- Center for Cancer and Blood Disorders
- Department of Child Health, College of Medicine, University of Arizona, Phoenix, Arizona
| | | | - Sanjay Shah
- Center for Cancer and Blood Disorders
- Department of Child Health, College of Medicine, University of Arizona, Phoenix, Arizona
| | - Todd Abruzzo
- Radiology, Phoenix Children's Hospital, Phoenix, Arizona
- Department of Child Health, College of Medicine, University of Arizona, Phoenix, Arizona
- College of Medicine, Mayo Clinic, Phoenix, Arizona
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3
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Ostrem BEL, Godfrey D, Caruso PA, Musolino PL. Monogenic Causes of Cerebrovascular Disease in Childhood: A Case Series. Pediatr Neurol 2023; 149:39-43. [PMID: 37776659 DOI: 10.1016/j.pediatrneurol.2023.08.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 08/16/2023] [Accepted: 08/18/2023] [Indexed: 10/02/2023]
Abstract
BACKGROUND Despite an increase in the number of genes associated with pediatric stroke, imaging phenotypes in children have not been well reported. Guidelines are needed to facilitate the identification and treatment of patients with monogenic causes of cerebrovascular disorders. METHODS We performed a retrospective review of imaging and medical records of patients aged zero to 21 years with monogenic causes of vascular malformations, small or large vessel disease, transient ischemic attacks, and/or ischemic or hemorrhagic stroke. We classified patients according to their imaging phenotype and reviewed neurological and systemic features and management strategies. We reviewed the literature to identify genes associated with cerebrovascular disorders presenting in childhood. RESULTS We identified 18 patients with monogenic causes of cerebrovascular disorders and classified each patient as belonging to one or more of three cerebrovascular phenotypes according to predominant imaging characteristics: small vessel disease, large vessel disease, and/or vascular malformations. Preventative treatments included aspirin, N-acetylcysteine, tocilizumab, therapeutic low-molecular-weight heparin, and resection of vascular malformations. CONCLUSIONS Classifying pediatric patients with cerebrovascular disorders by imaging phenotype can aid in determining the next steps in genetic testing and treatment.
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Affiliation(s)
- Bridget E L Ostrem
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts; Department of Neurology, University of California, San Francisco, San Francisco, California.
| | - Deena Godfrey
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts
| | - Paul A Caruso
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts; Lenox Hill Radiology and Medical Imaging Associates, New York, New York
| | - Patricia L Musolino
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts
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4
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Markovic I, Jocic-Jakubi B, Milenkovic Z. Early arteriopathy in Aicardi-Goutières syndrome 5. Case report and review of literature. Neuroradiol J 2023; 36:740-745. [PMID: 36722173 PMCID: PMC10649525 DOI: 10.1177/19714009231154677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Aicardi-Goutières syndrome (AGS) is an autosomal recessive disease that mimics congenital viral infection and mainly affects the brain, immune system, and skin. The dominant clinical symptom is the subacute onset of severe encephalopathy, which manifests as irritability, loss of ability, slowing of head growth, and poor nutrition. Arteriopathy in AGS is an uncommon manifestation usually associated with mutations in the SAMHD1 gene. We present a rare case of a 3-year-old male due to failure to thrive, global developmental delay, microcephaly, poor vision, upper and lower limbs spasticity, and gastroesophageal reflux disease (GERD), who harbored early stenotic lesions of the large and medium intracranial arteries with ischemic sequelae in the early postnatal life. Performed genetic testing confirmed homozygous gene mutation, SAMHD1 associated with AGS type 5. By reviewing the available literature, we were able to find only one patient whose arterial lesions were diagnosed after 6 months.
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Affiliation(s)
- Ivana Markovic
- Department of Radiology and Molecular Imaging, Sultan Qaboos University Hospital, Muscat, Oman
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5
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Wang W, Wang W, Peng S, Gao S, Quan M, Gou L, Wang C, Sun Z, Li Z, Lian D, Song H. Tocilizumab reduces the unmanageable inflammatory reaction of a patient with Aicardi-Goutières syndrome type 7 during treatment with ruxolitinib. Pediatr Rheumatol Online J 2023; 21:117. [PMID: 37828538 PMCID: PMC10571391 DOI: 10.1186/s12969-023-00899-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 09/25/2023] [Indexed: 10/14/2023] Open
Abstract
BACKGROUND Aicardi-Goutières syndrome (AGS) is a rare hereditary early-onset encephalopathy characterized by upregulation of the type I interferon pathway, poorly responsive to conventional immunosuppression. CASE PRESENTATION We describe a 7-year-old Chinese boy who developed symptoms at the age of 6 months. He presented with a chilblain-like rash, leukopenia, neutropenia, elevated liver enzymesgrowth retardation, microcephaly, elevated acute phase reactants, intracranial calcification and leukodystrophy. At the age of 3 years old, whole-exome sequencing confirmed a de novo heterozygous gain-of-function mutation, c.1016 C > A (p.Ala339Asp), in the IFIH1 gene, and he was diagnosed with AGS7. He was treated with ruxolitinib accompanied by steroids and thalidomide for about four years. The rash, hematological manifestations, and the liver function were all improved, but the erythrocyte sedimentation rate remained consistently elevated until the addition of tocilizumab, a monoclonal antibody against interleukin 6. CONCLUSIONS Ruxolitinib was not successful in suppressing the inflammatory process, and tocilizumab produced highly encouraging results in reducing the inflammatory reaction of AGS. The study makes a significant contribution to the literature because we may found a potential alternative therapeutic option for AGS.
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Affiliation(s)
- Wei Wang
- Department of Pediatrics, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing, 100730, China
| | - Wei Wang
- Department of Pediatrics, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing, 100730, China
| | - Siming Peng
- Department of Pediatrics, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing, 100730, China
| | - Sihao Gao
- Department of Pediatrics, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing, 100730, China
| | - Meiying Quan
- Department of Pediatrics, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing, 100730, China
| | - Lijuan Gou
- Department of Pediatrics, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing, 100730, China
| | - Changyan Wang
- Department of Pediatrics, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing, 100730, China
| | - Zhixing Sun
- Department of Pediatrics, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing, 100730, China
| | - Zhuo Li
- Department of Pediatrics, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing, 100730, China
| | - Dongmei Lian
- Department of Pediatrics, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing, 100730, China
| | - Hongmei Song
- Department of Pediatrics, Peking Union Medical College, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan Wangfujing Dongcheng District, Beijing, 100730, China.
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Dell'Isola GB, Dini G, Culpepper KL, Portwood KE, Ferrara P, Di Cara G, Verrotti A, Lodolo M. Clinical spectrum and currently available treatment of type I interferonopathy Aicardi-Goutières syndrome. World J Pediatr 2023; 19:635-643. [PMID: 36650407 PMCID: PMC10258176 DOI: 10.1007/s12519-022-00679-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 12/22/2022] [Indexed: 01/18/2023]
Abstract
BACKGROUND Aicardi-Goutières syndrome (AGS) is a genetically determined disorder with a variable phenotype. Since the original description of AGS, advances in gene sequencing techniques have resulted in a significant broadening of the phenotypic spectrum associated with AGS genes, and new clinical pictures have emerged beyond the classic presentation. The aim of this review is to provide a comprehensive analysis of the clinical spectrum of AGS and report currently available treatments and new immunosuppressive strategies. DATA SOURCES Literature reviews and original research articles were collected from databases, including PubMed and ClinicalTrials.gov. Relevant articles about AGS were included. RESULTS The involvement of the nervous system certainly represents the major cause of mortality and morbidity in AGS patients. However, other clinical manifestations, such as chilblains, hepatosplenomegaly, and hematological disturbances, may lead to the diagnosis and considerably impact the prognosis and overall quality of life of these patients. Therapeutic approaches of AGS are limited to interventions aimed at specific symptoms and the management of multiple comorbidities. However, advances in understanding the pathogenesis of AGS could open new and more effective therapies. CONCLUSIONS The over-activation of innate immunity due to upregulated interferon production plays a critical role in AGS, leading to multi-organ damage with the main involvement of the central nervous system. To date, there is no specific and effective treatment for AGS. New drugs specifically targeting the interferon pathway may bring new hope to AGS patients.
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Affiliation(s)
| | - Gianluca Dini
- Department of Pediatrics, University of Perugia, Giorgio Menghini Square, 06129, Perugia, Italy
| | | | - Katherin Elizabeth Portwood
- Department of Pediatrics, Division of Child Neurology, University of Florida, UF Health Shands Children's Hospital, Gainesville, FL, USA
| | - Pietro Ferrara
- Unit of Pediatrics, Campus Bio-Medico University, Rome, Italy
| | - Giuseppe Di Cara
- Department of Pediatrics, University of Perugia, Giorgio Menghini Square, 06129, Perugia, Italy
| | - Alberto Verrotti
- Department of Pediatrics, University of Perugia, Giorgio Menghini Square, 06129, Perugia, Italy
| | - Mauro Lodolo
- Department of Pediatrics, Division of Child Neurology, University of Florida, UF Health Shands Children's Hospital, Gainesville, FL, USA
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Joshi TP, Wang HY, Athukuri P, Bohac S, Farr MA, Hinson D, Kahla JA, Khalfe N, McBee DB, Stroh R, Walters N, Ren V. Biologic Therapies for the Management of Cutaneous Findings in Genodermatoses: A Review. Am J Clin Dermatol 2022; 23:673-688. [PMID: 35606649 DOI: 10.1007/s40257-022-00700-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2022] [Indexed: 01/17/2023]
Abstract
Genodermatoses are genetically inherited dermatologic conditions. The management of cutaneous findings in genodermatoses is challenging, and first-line therapies, such as steroids and/or retinoids, are often inadequate. In recent years, research on the molecular basis of genodermatoses has led to the use of biologic therapies for intractable disease. Here, we review the evidence regarding the use of available biologic therapies for the management of dermatologic findings in genodermatoses. Biologic therapies appear to be promising therapeutic options for several recalcitrant genodermatoses, especially those with underlying immune dysregulation. However, not all genodermatoses are amenable to biologic therapies, and some have been shown to paradoxically worsen under treatment. Biologic therapies offer a novel avenue to target refractory genodermatoses. However, evidence supporting the use of biologic therapies in the management of genodermatoses is mostly limited to case reports and case series. Further studies are warranted to determine the safety and efficacy of biologic therapies for the management of cutaneous findings in genodermatoses.
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8
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Mineharu Y, Miyamoto S. RNF213 and GUCY1A3 in Moyamoya Disease: Key Regulators of Metabolism, Inflammation, and Vascular Stability. Front Neurol 2021; 12:687088. [PMID: 34381413 PMCID: PMC8350054 DOI: 10.3389/fneur.2021.687088] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 06/24/2021] [Indexed: 12/24/2022] Open
Abstract
Moyamoya disease is an idiopathic chronically progressive cerebrovascular disease, which causes both ischemic and hemorrhagic stroke. Genetic studies identified RNF213/Mysterin and GUCY1A3 as disease-causing genes. They were also known to be associated with non-moyamoya intracranial large artery disease, coronary artery disease and pulmonary artery hypertension. This review focused on these two molecules and their strong linker, calcineurin/NFAT signaling and caveolin to understand the pathophysiology of moyamoya disease and related vascular diseases. They are important regulators of lipid metabolism especially lipotoxicity, NF-κB mediated inflammation, and nitric oxide-mediated vascular protection. Although intimal thickening with fibrosis and damaged vascular smooth muscle cells are the distinguishing features of moyamoya disease, origin of the fibrous tissue and the mechanism of smooth muscle cell damages remains not fully elucidated. Endothelial cells and smooth muscle cells have long been a focus of interest, but other vascular components such as immune cells and extracellular matrix also need to be investigated in future studies. Molecular research on moyamoya disease would give us a clue to understand the mechanism preserving vascular stability.
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Affiliation(s)
- Yohei Mineharu
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan
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Monogenic Autoinflammatory Diseases: State of the Art and Future Perspectives. Int J Mol Sci 2021; 22:ijms22126360. [PMID: 34198614 PMCID: PMC8232320 DOI: 10.3390/ijms22126360] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/10/2021] [Accepted: 06/11/2021] [Indexed: 12/18/2022] Open
Abstract
Systemic autoinflammatory diseases are a heterogeneous family of disorders characterized by a dysregulation of the innate immune system, in which sterile inflammation primarily develops through antigen-independent hyperactivation of immune pathways. In most cases, they have a strong genetic background, with mutations in single genes involved in inflammation. Therefore, they can derive from different pathogenic mechanisms at any level, such as dysregulated inflammasome-mediated production of cytokines, intracellular stress, defective regulatory pathways, altered protein folding, enhanced NF-kappaB signalling, ubiquitination disorders, interferon pathway upregulation and complement activation. Since the discover of pathogenic mutations of the pyrin-encoding gene MEFV in Familial Mediterranean Fever, more than 50 monogenic autoinflammatory diseases have been discovered thanks to the advances in genetic sequencing: the advent of new genetic analysis techniques and the discovery of genes involved in autoinflammatory diseases have allowed a better understanding of the underlying innate immunologic pathways and pathogenetic mechanisms, thus opening new perspectives in targeted therapies. Moreover, this field of research has become of great interest, since more than a hundred clinical trials for autoinflammatory diseases are currently active or recently concluded, allowing us to hope for considerable acquisitions for the next few years. General paediatricians need to be aware of the importance of this group of diseases and they should consider autoinflammatory diseases in patients with clinical hallmarks, in order to guide further examinations and refer the patient to a specialist rheumatologist. Here we resume the pathogenesis, clinical aspects and diagnosis of the most important autoinflammatory diseases in children.
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10
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Tesser A, Pin A, Mencaroni E, Gulino V, Tommasini A. Vasculitis, Autoimmunity, and Cytokines: How the Immune System Can Harm the Brain. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:5585. [PMID: 34073717 PMCID: PMC8197198 DOI: 10.3390/ijerph18115585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/14/2021] [Accepted: 05/19/2021] [Indexed: 02/06/2023]
Abstract
More and more findings suggest that neurological disorders could have an immunopathological cause. Thus, immune-targeted therapies are increasingly proposed in neurology (even if often controversial), as anakinra, inhibiting IL-1 for febrile inflammatory illnesses, and JAK inhibitors for anti-interferons treatment. Precision medicine in neurology could be fostered by a better understanding of the disease machinery, to develop a rational use of immuno-modulators in clinical trials. In this review, we focus on monogenic disorders with neurological hyper-inflammation/autoimmunity as simplified "models" to correlate immune pathology and targeted treatments. The study of monogenic models yields great advantages for the elucidation of the pathogenic mechanisms that can be reproduced in cellular/animal models, overcoming the limitations of biological samples to study. Moreover, monogenic disorders provide a unique tool to study the mechanisms of neuroinflammatory and autoimmune brain damage, in all their manifestations. The insight of clinical, pathological, and therapeutic aspects of the considered monogenic models can impact knowledge about brain inflammation and can provide useful hints to better understand and cure some neurologic multifactorial disorders.
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Affiliation(s)
- Alessandra Tesser
- Department of Pediatrics, Institute for Maternal and Child Health-IRCCS “Burlo Garofolo”, 34137 Trieste, Italy; (A.T.); (A.T.)
| | - Alessia Pin
- Department of Pediatrics, Institute for Maternal and Child Health-IRCCS “Burlo Garofolo”, 34137 Trieste, Italy; (A.T.); (A.T.)
| | - Elisabetta Mencaroni
- Department of Pediatrics, Ospedale Santa Maria Misericordia, 06123 Perugia, Italy;
| | - Virginia Gulino
- Family Pediatrician, Valnerina District, UslUmbria2, 06046 Norcia, Italy;
| | - Alberto Tommasini
- Department of Pediatrics, Institute for Maternal and Child Health-IRCCS “Burlo Garofolo”, 34137 Trieste, Italy; (A.T.); (A.T.)
- Department of Medicine, Surgery and Health Sciences, University of Trieste, 34149 Trieste, Italy
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11
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Sundercombe SL, Berbic M, Evans CA, Cliffe C, Elakis G, Temple SEL, Selvanathan A, Ewans L, Quayum N, Nixon CY, Dias KR, Lang S, Richards A, Goh S, Wilson M, Mowat D, Sachdev R, Sandaradura S, Walsh M, Farrar MA, Walsh R, Fletcher J, Kirk EP, Teunisse GM, Schofield D, Buckley MF, Zhu Y, Roscioli T. Clinically Responsive Genomic Analysis Pipelines: Elements to Improve Detection Rate and Efficiency. J Mol Diagn 2021; 23:894-905. [PMID: 33962052 DOI: 10.1016/j.jmoldx.2021.04.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 03/27/2021] [Accepted: 04/21/2021] [Indexed: 11/25/2022] Open
Abstract
Massively parallel sequencing has markedly improved mendelian diagnostic rates. This study assessed the effects of custom alterations to a diagnostic genomic bioinformatic pipeline in response to clinical need and derived practice recommendations relative to diagnostic rates and efficiency. The Genomic Annotation and Interpretation Application (GAIA) bioinformatics pipeline was designed to detect panel, exome, and genome sample integrity and prioritize gene variants in mendelian disorders. Reanalysis of selected negative cases was performed after improvements to the pipeline. GAIA improvements and their effect on sensitivity are described, including addition of a PubMed search for gene-disease associations not in the Online Mendelian Inheritance of Man database, inclusion of a process for calling low-quality variants (known as QPatch), and gene symbol nomenclature consistency checking. The new pipeline increased the diagnostic rate and reduced staff costs, resulting in a saving of US$844.34 per additional diagnosis. Recommendations for genomic analysis pipeline requirements are summarized. Clinically responsive bioinformatics pipeline improvements increase diagnostic sensitivity and increase cost-effectiveness.
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Affiliation(s)
| | - Marina Berbic
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia; School of Women's and Children's Health, University of New South Wales Sydney, Kensington, New South Wales, Australia
| | - Carey-Anne Evans
- Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia
| | - Corrina Cliffe
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - George Elakis
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Suzanna E L Temple
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia; Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia; Centre for Clinical Genetics, Sydney Children's Hospital, Sydney, Randwick, New South Wales, Australia
| | - Arthavan Selvanathan
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia; Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia; Discipline of Child and Adolescent Health, The University of Sydney, New South Wales, Australia
| | - Lisa Ewans
- Department of Medical Genomics, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia; Central Clinical School, Sydney Medical School, The University of Sydney, New South Wales, Australia
| | - Nila Quayum
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Cheng-Yee Nixon
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia; Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia
| | - Kerith-Rae Dias
- Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia; Prince of Wales Clinical School, Faculty of Medicine, University of New South Wales Sydney, Kensington, New South Wales, Australia
| | - Sarah Lang
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Anna Richards
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Shuxiang Goh
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia; Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia
| | - Meredith Wilson
- Department of Clinical Genetics, Children's Hospital at Westmead, Sydney, Westmead, New South Wales, Australia
| | - David Mowat
- Centre for Clinical Genetics, Sydney Children's Hospital, Sydney, Randwick, New South Wales, Australia
| | - Rani Sachdev
- Centre for Clinical Genetics, Sydney Children's Hospital, Sydney, Randwick, New South Wales, Australia
| | - Sarah Sandaradura
- Department of Clinical Genetics, Children's Hospital at Westmead, Sydney, Westmead, New South Wales, Australia
| | - Maie Walsh
- Genetic Medicine Department, Royal Melbourne Hospital, Parkville, Victoria, Australia
| | - Michelle A Farrar
- School of Women's and Children's Health, University of New South Wales Sydney, Kensington, New South Wales, Australia; Neurology Department, Sydney Children's Hospital, Sydney, Randwick, New South Wales, Australia
| | - Rebecca Walsh
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Janice Fletcher
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Edwin P Kirk
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia; School of Women's and Children's Health, University of New South Wales Sydney, Kensington, New South Wales, Australia; Centre for Clinical Genetics, Sydney Children's Hospital, Sydney, Randwick, New South Wales, Australia
| | - Guus M Teunisse
- Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia
| | - Deborah Schofield
- Centre for Economic Impacts of Genomic Medicine, Macquarie Business School, Macquarie University, Macquarie Park, New South Wales, Australia
| | - Michael Francis Buckley
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Ying Zhu
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia; Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia; Genetics of Learning Disability Service, Hunter Genetics, Waratah Newcastle, New South Wales, Australia
| | - Tony Roscioli
- NSW Health Pathology Randwick Genomics, Prince of Wales Hospital, Randwick, New South Wales, Australia; Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia; Centre for Clinical Genetics, Sydney Children's Hospital, Sydney, Randwick, New South Wales, Australia.
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12
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He T, Xia Y, Yang J. Systemic inflammation and chronic kidney disease in a patient due to the RNASEH2B defect. Pediatr Rheumatol Online J 2021; 19:9. [PMID: 33482855 PMCID: PMC7821736 DOI: 10.1186/s12969-021-00497-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 01/11/2021] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Aicardi-Goutières (AGS) is a rare immune dysregulated disease due to mutations in TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, ADAR1, or IFIH1. Clinical features include basal ganglia calcifications, white matter abnormalities, and cerebral atrophy. Severe systemic inflammation and chronic kidney disease (CKD) are extremely rare in AGS. Herein, we report a patient presenting with systemic inflammation and CKD to broaden the clinical phenotype spectrum of the RNASEH2B defect. METHODS All testing and molecular genetic analysis were performed after obtaining the informed consent of the parents. Demographic, clinical, and laboratory findings were abstracted from outpatient and inpatient encounters. Cerebral magnetic resonance imaging (MRI), computed tomography (CT) scans, and renal biopsy histopathology reports were reviewed and summarized. Whole exome sequencing (WES) was performed on peripheral blood cells. After exposure to cGAMP in vitro for 24 h, mRNA expression of 12 IFN-stimulated cytokine genes in PBMCs was assessed. Serum cytokine levels were detected by Milliplex. RESULTS A 11-year-old girl presented with recurrent aseptic fever, arthritis, chilblains, failure to thrive, mild hearing loss, and neurological manifestations. Laboratory and immunologic findings demonstrated lymphopenia, low complement levels, positive autoantibodies, elevated levels of acute-phase reactants and inflammatory cytokines. Cerebral imaging showed cerebral atrophy, white matter abnormalities, and intracranial calcification. Renal biopsy showed glomerular sclerosis in 3 of 14 glomeruli, infiltration of lymphocytes and other mononuclear cells. WES revealed a homozygous and heterozygous mutations in RNASEH2B. Over-expression of IFN-stimulated cytokine genes was observed, including IFI44, IFI27, IFIT1, IFIT2, IFIT3, ISG15, OAS1, and SIGLEC1. CONCLUSIONS To date, only two cases with AGS have been reported to have renal disease. Here, we describe a patient with both homozygous and heterozygous variants in RNASEH2B, presenting with neurological manifestations, persistently systemic autoinflammation, and CKD. CKD has never been reported in patients with AGS due to the RNASEH2B defect. TRIAL REGISTRATION Not applicable; this was a retrospective study.
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Affiliation(s)
- Tingyan He
- Department of Rheumatology and Immunology, Shenzhen Children's Hospital, 7019 Yitian Road, Shenzhen, 518038, China.
| | - Yu Xia
- grid.452787.b0000 0004 1806 5224Department of Rheumatology and Immunology, Shenzhen Children’s Hospital, 7019 Yitian Road, Shenzhen, 518038 China
| | - Jun Yang
- Department of Rheumatology and Immunology, Shenzhen Children's Hospital, 7019 Yitian Road, Shenzhen, 518038, China.
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13
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Aikman I, Makowski K, Wenger O, Rossman I, Solomon JD. Microcephaly, Hypotonia, and Intracranial Calcifications in an 11-Week-Old Boy. Pediatrics 2020; 146:peds.2019-2795. [PMID: 32820067 DOI: 10.1542/peds.2019-2795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/25/2020] [Indexed: 11/24/2022] Open
Abstract
An 11-week-old unvaccinated, term Amish boy initially presented with poor feeding, microcephaly, failure to thrive, and developmental delays. His physical examination was significant for both weight and head circumference being less than the third percentile, and he was noted to have micrognathia, truncal hypotonia, and head lag. He was admitted to the pediatric hospital medicine service for further diagnostic evaluation. Laboratory studies assessing for endocrinological and metabolic etiologies yielded negative results, and imaging studies (including a chest radiograph, echocardiogram, and abdominal ultrasound) were normal. However, intracranial calcifications were noted on a head ultrasound. The etiology of his constellation of symptoms was initially thought to be infectious, but the ultimate diagnosis was not made until after discharge from the pediatric hospital medicine service.
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Affiliation(s)
- Inga Aikman
- Akron Children's Hospital, Akron, Ohio; .,Division of Critical Care and Hospital Medicine, Department of Pediatrics, Brody School of Medicine, East Carolina University, Greenville, North Carolina; and
| | | | - Olivia Wenger
- Akron Children's Hospital, Akron, Ohio.,New Leaf Center, Mount Eaton, Ohio
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14
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Papa R, Volpi S, Gattorno M. Monogenetic causes of chilblains, panniculitis and vasculopathy: the Type I interferonopathies. GIORN ITAL DERMAT V 2020; 155:590-598. [PMID: 32618445 DOI: 10.23736/s0392-0488.20.06709-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Type I interferonopathies are a clinically heterogeneous group of inherited disorders of the innate immune system characterized by constitutive activation of the type I interferon signaling pathway. Cutaneous vasculopathy, lipodystrophy, interstitial lung disease and brain calcifications are the typical manifestations characterizing affected patients. The pathogenic mechanism commonly underlying these disorders is the abnormal activation of immune pathways involved in recognition of non-self-oligonucleotides. These natural defenses against virus consent humans to survive the infections. Target therapies capable of inhibiting type I interferon signaling pathway seem effective in these patients, albeit with possible incomplete responses and severe side effects.
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Affiliation(s)
- Riccardo Papa
- Autoinflammatory Diseases and Immunodeficiencies Center, IRCCS Istituto Giannina Gaslini, Genoa, Italy.,Department of Neuroscience, Rehabilitation, Ophthalmology, Genetic and Maternal-Infant Sciences, University of Genoa, Genoa, Italy
| | - Stefano Volpi
- Autoinflammatory Diseases and Immunodeficiencies Center, IRCCS Istituto Giannina Gaslini, Genoa, Italy - .,Department of Neuroscience, Rehabilitation, Ophthalmology, Genetic and Maternal-Infant Sciences, University of Genoa, Genoa, Italy
| | - Marco Gattorno
- Autoinflammatory Diseases and Immunodeficiencies Center, IRCCS Istituto Giannina Gaslini, Genoa, Italy
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15
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Tonduti D, Fazzi E, Badolato R, Orcesi S. Novel and emerging treatments for Aicardi-Goutières syndrome. Expert Rev Clin Immunol 2020; 16:189-198. [PMID: 31855085 DOI: 10.1080/1744666x.2019.1707663] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Introduction: Aicardi-Goutières syndrome (AGS) is the prototype of the type I interferonopathies, a new heterogeneous group of autoinflammatory disorders in which type I interferon plays a pivotal role. The disease usually manifests itself during infancy, primarily affecting the brain and the skin, and is characterized by cerebrospinal fluid chronic lymphocytosis and raised levels of interferon-alpha and by cardinal neuroradiological features: cerebral calcification, leukoencephalopathy and cerebral atrophy. Recently many aspects of the pathogenesis of AGS have been clarified, making it possible to hypothesize new therapeutic strategies.Areas covered: We here review recent data concerning pathogenesis and novel therapeutic strategies in AGS, including the use of Janus kinase inhibitors, reverse transcriptase inhibitors, anti-IFN-α antibodies, anti-interleukin antibodies, antimalarial drugs and other cGAS inhibitors.Expert opinion: Thanks to the identification of the molecular basis of AGS, many aspects of its pathogenesis have been clarified, making it possible to propose new therapeutic strategies for AGS and type I interferonopathies. A number of therapeutic options are now becoming possible, even though their efficacy is still to be proven. However, in spite of research advances coming from clinical trials and case series, there are still a number of open questions, which urgently need to be addressed.
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Affiliation(s)
- Davide Tonduti
- Paediatric Neurology Unit, V. Buzzi Children's Hospital, Milan, Italy
| | - Elisa Fazzi
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy.,Unit of Child Neurology and Psychiatry, ASST Spedali Civili of Brescia, Brescia, Italy
| | - Raffaele Badolato
- Molecular Medicine Institute "Angelo Nocivelli" and Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Simona Orcesi
- Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy.,Unit of Child and Adolescent Neurology, IRCCS Mondino Foundation, Pavia, Italy
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16
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Chen S, Bonifati S, Qin Z, St Gelais C, Wu L. SAMHD1 Suppression of Antiviral Immune Responses. Trends Microbiol 2018; 27:254-267. [PMID: 30336972 DOI: 10.1016/j.tim.2018.09.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/17/2018] [Accepted: 09/26/2018] [Indexed: 12/18/2022]
Abstract
SAMHD1 is a host triphosphohydrolase that degrades intracellular deoxynucleoside triphosphates (dNTPs) to a lower level that restricts viral DNA synthesis, and thus prevents replication of diverse viruses in nondividing cells. Recent progress indicates that SAMHD1 negatively regulates antiviral innate immune responses and inflammation through interacting with various key proteins in immune signaling and DNA damage-repair pathways. SAMHD1 can also modulate antibody production in adaptive immune responses. In this review, we summarize how SAMHD1 regulates antiviral immune responses through distinct mechanisms, and discuss the implications of these new functions of SAMHD1. Furthermore, we propose important new questions and future directions that can advance functional and mechanistic studies of SAMHD1-mediated immune regulation during viral infections.
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Affiliation(s)
- Shuliang Chen
- School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, PR China; Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Serena Bonifati
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Zhihua Qin
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Corine St Gelais
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA
| | - Li Wu
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH 43210, USA; Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH 43210, USA.
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Caso F, Costa L, Nucera V, Barilaro G, Masala IF, Talotta R, Caso P, Scarpa R, Sarzi-Puttini P, Atzeni F. From autoinflammation to autoimmunity: old and recent findings. Clin Rheumatol 2018; 37:2305-2321. [PMID: 30014358 DOI: 10.1007/s10067-018-4209-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 07/06/2018] [Accepted: 07/09/2018] [Indexed: 12/13/2022]
Abstract
Autoimmune diseases and autoinflammatory diseases have a number of similar etiopathogenetic and clinical characteristics, including genetic predisposition and recurrent systemic inflammatory flares. The first phase of ADs involves innate immunity: by means of TLRs, autoantigen presentation, B and T cell recruitment and autoantibody synthesis. The second phase involves adaptive immunity, a self-sustaining process in which immune complexes containing nucleic acids and autoantibodies activate self-directed inflammation. The link between autoimmunity and autoinflammation is IL-1ß, which is crucial in connecting the innate immune response due to NLR activation and the adaptive immune responses of T and B cells. In conclusion, although ADs are still considered adaptive immunity-mediated disorders, there is increasing evidence that innate immunity and inflammasomes are also involved. The aim of this review is to highlight the link between the innate and adaptive immune mechanisms involved in autoimmune diseases.
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Affiliation(s)
- Francesco Caso
- Rheumatology Unit, Department of Clinical Medicine and Surgery, University Federico II, Via Sergio Pansini, 5, Naples, Italy
| | - Luisa Costa
- Rheumatology Unit, Department of Clinical Medicine and Surgery, University Federico II, Via Sergio Pansini, 5, Naples, Italy
| | - Valeria Nucera
- Rheumatology Unit, University of Messina, Messina, Italy
| | - Giuseppe Barilaro
- Department of Internal Medicine, IRCCS San Raffaele Pisana, Rome, Italy
| | | | - Rossella Talotta
- Rheumatology Unit, ASST Fatebenefratelli Sacco Buzzi, Milan, Italy
| | - Paolo Caso
- Geriatric Unit, Faculty of Medicine and Psychology, S. Andrea Hospital, "Sapienza" University of Rome, Rome, Italy
| | - Raffaele Scarpa
- Rheumatology Unit, Department of Clinical Medicine and Surgery, University Federico II, Via Sergio Pansini, 5, Naples, Italy.
| | | | - Fabiola Atzeni
- Rheumatology Unit, University of Messina, Messina, Italy
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SAMHD1 suppresses innate immune responses to viral infections and inflammatory stimuli by inhibiting the NF-κB and interferon pathways. Proc Natl Acad Sci U S A 2018; 115:E3798-E3807. [PMID: 29610295 DOI: 10.1073/pnas.1801213115] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Sterile alpha motif and HD-domain-containing protein 1 (SAMHD1) blocks replication of retroviruses and certain DNA viruses by reducing the intracellular dNTP pool. SAMHD1 has been suggested to down-regulate IFN and inflammatory responses to viral infections, although the functions and mechanisms of SAMHD1 in modulating innate immunity remain unclear. Here, we show that SAMHD1 suppresses the innate immune responses to viral infections and inflammatory stimuli by inhibiting nuclear factor-κB (NF-κB) activation and type I interferon (IFN-I) induction. Compared with control cells, infection of SAMHD1-silenced human monocytic cells or primary macrophages with Sendai virus (SeV) or HIV-1, or treatment with inflammatory stimuli, induces significantly higher levels of NF-κB activation and IFN-I induction. Exogenous SAMHD1 expression in cells or SAMHD1 reconstitution in knockout cells suppresses NF-κB activation and IFN-I induction by SeV infection or inflammatory stimuli. Mechanistically, SAMHD1 inhibits NF-κB activation by interacting with NF-κB1/2 and reducing phosphorylation of the NF-κB inhibitory protein IκBα. SAMHD1 also interacts with the inhibitor-κB kinase ε (IKKε) and IFN regulatory factor 7 (IRF7), leading to the suppression of the IFN-I induction pathway by reducing IKKε-mediated IRF7 phosphorylation. Interactions of endogenous SAMHD1 with NF-κB and IFN-I pathway proteins were validated in human monocytic cells and primary macrophages. Comparing splenocytes from SAMHD1 knockout and heterozygous mice, we further confirmed SAMHD1-mediated suppression of NF-κB activation, suggesting an evolutionarily conserved property of SAMHD1. Our findings reveal functions of SAMHD1 in down-regulating innate immune responses to viral infections and inflammatory stimuli, highlighting the importance of SAMHD1 in modulating antiviral immunity.
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