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Ahmari AA, Alsmadi O, Sheereen A, Elamin T, Jabr A, El-Baik L, Alhissi S, Saud BA, Al-Awwami M, Fawaz IA, Ayas M, Siddiqui K, Hawwari A. Genetic and clinical characteristics of pediatric patients with familial hemophagocytic lymphohistiocytosis. Blood Res 2021; 56:86-101. [PMID: 34083498 PMCID: PMC8246041 DOI: 10.5045/br.2021.2020308] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 05/02/2021] [Accepted: 05/18/2021] [Indexed: 12/15/2022] Open
Abstract
Background Our study was designed to investigate the frequencies and distributions of familial hemophagocytic lymphohistiocytosis (FHL) associated genes in Saudi patients. Methods FHL associated gene screening was performed on 87 Saudi patients who were diagnosed with hemophagocytic lymphohistiocytosis (HLH) between 1995 and 2014. The clinical and biochemical profiles were also retrospectively captured and analyzed. Results Homozygous mutations and mono-allelic variants were identified in 66 (75.9%) and 3 (3.5%) of the study participants, respectively. STXBP2 was the most frequently mutated gene (36% of patients) and mutations in STXBP2 and STX11 accounted for 58% of all FHL cases and demonstrated a specific geographical pattern. Patients in the FHL group presented at a significantly younger age than those belonging to the unknown-genetics group (median, 3.9 vs. 9.4 mo; P=0.005). The presenting clinical features were similar among the various genetic groups and the 5-year overall survival (OS) was 55.4% with a 5.6 year median follow-up. Patients with PRF1 mutations had a significantly poorer 5-year OS (21.4%, P=0.008) and patients undergoing hematopoietic stem cell transplant (72.4%) had a significantly better 5-year OS (66.5% vs. 0%, P=0.001). Conclusion Our study revealed the predominance of the STXBP2 mutations in Saudi patients with FHL. A genetic diagnosis was possible in 80% of the cohort and our data showed improved survival in FHL patients who underwent hematopoietic stem cell transplant.
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Affiliation(s)
- Ali Al Ahmari
- Department of Pediatric Hematology/Oncology, King Faisal Specialist Hospital and Research Center, Saudi Arabia.,College of Medicine, AlFaisal University, Riyadh, Saudi Arabia
| | - Osama Alsmadi
- Section of Immunogenetics, Department of Genetics, Research Center, King Faisal Specialist Hospital and Research Center, Saudi Arabia.,Cell Therapy, Applied Genomics, King Hussein Cancer Center, Amman, Jordan
| | - Atia Sheereen
- Section of Immunogenetics, Department of Genetics, Research Center, King Faisal Specialist Hospital and Research Center, Saudi Arabia
| | - Tanziel Elamin
- Section of Immunogenetics, Department of Genetics, Research Center, King Faisal Specialist Hospital and Research Center, Saudi Arabia
| | - Amal Jabr
- Section of Immunogenetics, Department of Genetics, Research Center, King Faisal Specialist Hospital and Research Center, Saudi Arabia
| | - Lina El-Baik
- Section of Immunogenetics, Department of Genetics, Research Center, King Faisal Specialist Hospital and Research Center, Saudi Arabia
| | - Safa Alhissi
- Section of Immunogenetics, Department of Genetics, Research Center, King Faisal Specialist Hospital and Research Center, Saudi Arabia
| | - Bandar Al Saud
- Department of Pediatric Allergy/Immunology, King Faisal Specialist Hospital and Research Center, Saudi Arabia
| | - Moheeb Al-Awwami
- Pathology and Laboratory Medicine, King Faisal Specialist Hospital and Research Center, Saudi Arabia
| | - Ibrahim Al Fawaz
- Department of Pediatric Hematology/Oncology, King Faisal Specialist Hospital and Research Center, Saudi Arabia.,College of Medicine, AlFaisal University, Riyadh, Saudi Arabia
| | - Mouhab Ayas
- Department of Pediatric Hematology/Oncology, King Faisal Specialist Hospital and Research Center, Saudi Arabia.,College of Medicine, AlFaisal University, Riyadh, Saudi Arabia
| | - Khawar Siddiqui
- Department of Pediatric Hematology/Oncology, King Faisal Specialist Hospital and Research Center, Saudi Arabia
| | - Abbas Hawwari
- Section of Immunogenetics, Department of Genetics, Research Center, King Faisal Specialist Hospital and Research Center, Saudi Arabia.,King Abdullah International Medical Research Center (KAIMRC), King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City Hospital, Al-Ahsa, Saudi Arabia
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2
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Benezech S, Walzer T, Charrier E, Heidelberg D, De Saint-Basile G, Bertrand Y, Belot A. Late-onset hemophagocytic lymphohistiocytosis with neurological presentation. Clin Case Rep 2017; 5:1743-1749. [PMID: 29152263 PMCID: PMC5676276 DOI: 10.1002/ccr3.1135] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/15/2017] [Accepted: 07/22/2017] [Indexed: 02/02/2023] Open
Abstract
Missense mutations in genes involved in familial hemophagocytic lymphohistiocytosis can delay the onset of this life-threatening disease. In children and adults, early recognition of aspecific features as neurological symptoms is crucial as urgent treatment is required.
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Affiliation(s)
- Sarah Benezech
- Department of Pediatrics Hospices Civils de Lyon Lyon France
| | - Thierry Walzer
- Institut National de la Santé et de la Recherche Médicale U1111 Université de Lyon 1 Lyon France
| | - Emily Charrier
- Institut National de la Santé et de la Recherche Médicale U1111 Université de Lyon 1 Lyon France
| | | | - Geneviève De Saint-Basile
- Institut National de la Santé et de la Recherche Médicale U768 CHU Paris - Hôpital Necker-Enfants Malades Paris France
| | - Yves Bertrand
- Hospices Civils de LyonInstitut d'Hématologie et Oncologie Pédiatrique Lyon France
| | - Alexandre Belot
- Institut National de la Santé et de la Recherche Médicale U1111 Université de Lyon 1 Lyon France.,Department of Rheumatology Hospices Civils de Lyon Lyon France
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3
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Finding a Balance between Protection and Pathology: The Dual Role of Perforin in Human Disease. Int J Mol Sci 2017; 18:ijms18081608. [PMID: 28757574 PMCID: PMC5578000 DOI: 10.3390/ijms18081608] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 07/20/2017] [Accepted: 07/20/2017] [Indexed: 01/08/2023] Open
Abstract
Perforin is critical for controlling viral infection and tumor surveillance. Clinically, mutations in perforin are viewed as unfavorable, as lack of this pore-forming protein results in lethal, childhood disease, familial hemophagocytic lymphohistiocytosis type 2 (FHL 2). However, many mutations in the coding region of PRF1 are not yet associated with disease. Animal models of viral-associated blood–brain barrier (BBB) disruption and experimental cerebral malaria (ECM) have identified perforin as critical for inducing pathologic central nervous system CNS vascular permeability. This review focuses on the role of perforin in both protecting and promoting human disease. It concludes with a novel hypothesis that diversity observed in the PRF1 gene may be an example of selective advantage that protects an individual from perforin-mediated pathology, such as BBB disruption.
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4
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Willenbring RC, Jin F, Hinton DJ, Hansen M, Choi DS, Pavelko KD, Johnson AJ. Modulatory effects of perforin gene dosage on pathogen-associated blood-brain barrier (BBB) disruption. J Neuroinflammation 2016; 13:222. [PMID: 27576583 PMCID: PMC5006384 DOI: 10.1186/s12974-016-0673-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 08/17/2016] [Indexed: 11/12/2022] Open
Abstract
Background CD8 T cell-mediated blood-brain barrier (BBB) disruption is dependent on the effector molecule perforin. Human perforin has extensive single nucleotide variants (SNVs), the significance of which is not fully understood. These SNVs can result in reduced, but not ablated, perforin activity or expression. However, complete loss of perforin expression or activity results in the lethal disease familial hemophagocytic lymphohistiocytosis type 2 (FHL 2). In this study, we address the hypothesis that a single perforin allele can alter the severity of BBB disruption in vivo using a well-established model of CNS vascular permeability in C57Bl/6 mice. The results of this study provide insight into the significance of perforin SNVs in the human population. Methods We isolated the effect a single perforin allele has on CNS vascular permeability through the use of perforin-heterozygous (perforin+/−) C57BL/6 mice in the peptide-induced fatal syndrome (PIFS) model of immune-mediated BBB disruption. Seven days following Theiler’s murine encephalomyelitis virus (TMEV) CNS infection, neuroinflammation and TMEV viral control were assessed through flow cytometric analysis and quantitative real-time PCR of the viral genome, respectively. Following immune-mediated BBB disruption, gadolinium-enhanced T1-weighted MRI, with 3D volumetric analysis, and confocal microscopy were used to define CNS vascular permeability. Finally, the open field behavior test was used to assess locomotor activity of mice following immune-mediated BBB disruption. Results Perforin-null mice had negligible CNS vascular permeability. Perforin-WT mice have extensive CNS vascular permeability. Interestingly, perforin-heterozygous mice had an intermediate level of CNS vascular permeability as measured by both gadolinium-enhanced T1-weighted MRI and fibrinogen leakage in the brain parenchyma. Differences in BBB disruption were not a result of increased CNS immune infiltrate. Additionally, TMEV was controlled in a perforin dose-dependent manner. Furthermore, a single perforin allele is sufficient to induce locomotor deficit during immune-mediated BBB disruption. Conclusions Perforin modulates BBB disruption in a dose-dependent manner. This study demonstrates a potentially advantageous role for decreased perforin expression in reducing BBB disruption. This study also provides insight into the effect SNVs in a single perforin allele could have on functional deficit in neurological disease.
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Affiliation(s)
- Robin C Willenbring
- Mayo Graduate School, Mayo Clinic, Rochester, MN, USA.,Department of Immunology, Mayo Clinic, Rochester, MN, USA
| | - Fang Jin
- Department of Immunology, Mayo Clinic, Rochester, MN, USA
| | - David J Hinton
- Mayo Graduate School, Mayo Clinic, Rochester, MN, USA.,Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - Mike Hansen
- Department of Immunology, Mayo Clinic, Rochester, MN, USA
| | - Doo-Sup Choi
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | | | - Aaron J Johnson
- Department of Immunology, Mayo Clinic, Rochester, MN, USA. .,Department of Neurology, Mayo Clinic, Rochester, MN, USA.
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5
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Abstract
Hemophagocytic lymphohistiocytosis (HLH) covers a wide array of related life-threatening conditions featuring ineffective immunity characterized by an uncontrolled hyperinflammatory response. HLH is often triggered by infection. Familial forms result from genetic defects in natural killer cells and cytotoxic T-cells, typically affecting perforin and intracellular vesicles. HLH is likely under-recognized, which contributes to its high morbidity and mortality. Early recognition is crucial for any reasonable attempt at curative therapy to be made. Current treatment regimens include immunosuppression, immune modulation, chemotherapy, and biological response modification, followed by hematopoietic stem-cell transplant (bone marrow transplant). A number of recent studies have contributed to the understanding of HLH pathophysiology, leading to alternate treatment options; however, much work remains to raise awareness and improve the high morbidity and mortality of these complex conditions.
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Affiliation(s)
- Melissa R George
- Department of Pathology, Penn State Milton S Hershey Medical Center, Hershey, PA, USA
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Al-Zadjali S, Al-Tamemi S, Elnour I, AlKindi S, Lapoumeroulie C, Al-Maamari S, Pathare A, Dennison D, Krishnamoorthy R. Clinical and molecular findings of chronic granulomatous disease in Oman: family studies. Clin Genet 2014; 87:185-9. [PMID: 24446915 DOI: 10.1111/cge.12351] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 01/16/2014] [Accepted: 01/17/2014] [Indexed: 11/27/2022]
Abstract
Chronic granulomatous disease (CGD), a rare inherited disorder of the innate immune system, results from mutations in any one of the five genes encoding the subunits of the nicotinamide adenine dinucleotide phosphate-oxidase (NADPH) oxidase enzyme, and is characterized by recurrent life-threatening bacterial and fungal infections. Molecular analysis of 14 Omani CGD patients from 10 families, diagnosed to have CGD on clinical (recurrent infections) and biochemical grounds (positive for both the nitroblue tetrazolium (NBT) test and the dihydrorhodamine (DHR-1,2,3 assay), revealed that only one patient had X-linked CGD, with a large deletion involving both the gp91-phox gene (CYBB) and the McLeod gene (XK). The remaining 13 patients were all homozygotes from a previously described c.579G>A (p.Trp193X) mutation in the NCF1 gene on chromosome 7, responsible for autosomal recessive CGD (AR-CGD). Although X-linked CGD is the most common type of CGD disorder in most population groups, AR-CGD is the most prevalent type in Oman.
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Dias C, McDonald A, Sincan M, Rupps R, Markello T, Salvarinova R, Santos RF, Menghrajani K, Ahaghotu C, Sutherland DP, Fortuno ES, Kollmann TR, Demos M, Friedman JM, Speert DP, Gahl WA, Boerkoel CF. Recurrent subacute post-viral onset of ataxia associated with a PRF1 mutation. Eur J Hum Genet 2013; 21:1232-9. [PMID: 23443029 PMCID: PMC3798831 DOI: 10.1038/ejhg.2013.20] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 11/19/2012] [Accepted: 01/23/2013] [Indexed: 12/14/2022] Open
Abstract
Inflammation is an important contributor to pediatric and adult neurodegeneration. Understanding the genetic determinants of neuroinflammation provides valuable insight into disease mechanism. We characterize a disorder of recurrent immune-mediated neurodegeneration. We report two sisters who presented with neurodegeneration triggered by infections. The proband, a previously healthy girl, presented at 22.5 months with ataxia and dysarthria following mild gastroenteritis. MRI at onset showed a symmetric signal abnormality of the cerebellar and peritrigonal white matter. Following a progressive course of partial remissions and relapses, she died at 5 years of age. Her older sister had a similar course following varicella infection, she died within 13 months. Both sisters had unremarkable routine laboratory testing, with exception of a transient mild cytopenia in the proband 19 months after presentation. Exome sequencing identified a biallelic perforin1 mutation (PRF1; p.R225W) previously associated with familial hemophagocytic lymphohistiocytosis (FHL). In contrast to FHL, these girls did not have hematopathology or cytokine overproduction. However, 3 years after disease onset, the proband had markedly deficient interleukin-1 beta (IL-1β) production. These observations extend the spectrum of disease associated with perforin mutations to immune-mediated neurodegeneration triggered by infection and possibly due to primary immunodeficiency.
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Affiliation(s)
- Cristina Dias
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- Genetics and Health Cluster, Child and Family Research Institute, BC Children's Hospital, Vancouver, British Columbia, Canada
| | - Allison McDonald
- Centre for Understanding and Preventing Infection in Children, Child and Family Research Institute, Vancouver, British Columbia, Canada
- Division of Infectious and Immunological Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Murat Sincan
- NIH Undiagnosed Diseases Program, NIH Office of Rare Diseases Research and NHGRI, Bethesda, MD, USA
| | - Rosemarie Rupps
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- Genetics and Health Cluster, Child and Family Research Institute, BC Children's Hospital, Vancouver, British Columbia, Canada
- Rare Disease Foundation, Vancouver, British Columbia, Canada
| | - Thomas Markello
- NIH Undiagnosed Diseases Program, NIH Office of Rare Diseases Research and NHGRI, Bethesda, MD, USA
| | - Ramona Salvarinova
- Division of Biochemical Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Rui F Santos
- Department of Radiology, BC Children's Hospital & University of British Columbia, Vancouver, British Columbia, Canada
| | - Kamal Menghrajani
- NIH Undiagnosed Diseases Program, NIH Office of Rare Diseases Research and NHGRI, Bethesda, MD, USA
| | - Chidi Ahaghotu
- NIH Undiagnosed Diseases Program, NIH Office of Rare Diseases Research and NHGRI, Bethesda, MD, USA
| | - Darren P Sutherland
- Centre for Understanding and Preventing Infection in Children, Child and Family Research Institute, Vancouver, British Columbia, Canada
- Division of Infectious and Immunological Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Edgardo S Fortuno
- Centre for Understanding and Preventing Infection in Children, Child and Family Research Institute, Vancouver, British Columbia, Canada
- Division of Infectious and Immunological Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Tobias R Kollmann
- Centre for Understanding and Preventing Infection in Children, Child and Family Research Institute, Vancouver, British Columbia, Canada
- Division of Infectious and Immunological Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michelle Demos
- Division of Neurology, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jan M Friedman
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- Genetics and Health Cluster, Child and Family Research Institute, BC Children's Hospital, Vancouver, British Columbia, Canada
| | - David P Speert
- Centre for Understanding and Preventing Infection in Children, Child and Family Research Institute, Vancouver, British Columbia, Canada
- Division of Infectious and Immunological Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - William A Gahl
- NIH Undiagnosed Diseases Program, NIH Office of Rare Diseases Research and NHGRI, Bethesda, MD, USA
| | - Cornelius F Boerkoel
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- Genetics and Health Cluster, Child and Family Research Institute, BC Children's Hospital, Vancouver, British Columbia, Canada
- NIH Undiagnosed Diseases Program, NIH Office of Rare Diseases Research and NHGRI, Bethesda, MD, USA
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9
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Nold-Petry CA, Lehrnbecher T, Jarisch A, Schwabe D, Pfeilschifter JM, Muhl H, Nold MF. Failure of interferon gamma to induce the anti-inflammatory interleukin 18 binding protein in familial hemophagocytosis. PLoS One 2010; 5:e8663. [PMID: 20072626 PMCID: PMC2800185 DOI: 10.1371/journal.pone.0008663] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Accepted: 12/07/2009] [Indexed: 11/19/2022] Open
Abstract
Background Familial hemophagocytosis (FHL) is a rare disease associated with defects in proteins involved in CD8+ T-cell cytotoxicity. Hyperactivation of immune cells results in a perilous, Th1-driven cytokine storm. We set out to explore the regulation of cytokines in an FHL patient who was clinically stable on low-dose immunosuppressive therapy after bone marrow transplantation over a six-month period. During this period, chimerism analyses showed that the fraction of host cells was between 1 and 10%. Both parents of the patient as well as healthy volunteers were studied for comparison. Methods/Principal Findings Using ELISA, quantitative real-time PCR, and clinical laboratory methods, we investigated constitutive and inducible cytokines, polymorphisms, and clinical parameters in whole blood and whole blood cultures. Although routine laboratory tests were within the normal range, the chemokines IP-10 and IL-8 as well as the cytokine IL-27p28 were increased up to 10-fold under constitutive and stimulated conditions compared to healthy controls. Moreover, high levels of IFNγ and TNFα were produced upon stimulation. Unexpectedly, IFNγ induction of IL-18 binding protein (IL-18BP) was markedly reduced (1.6-fold vs 5-fold in controls). The patient's mother featured intermediately increased cytokine levels, whereas levels in the father were similar to those in the controls. Conclusions/Significance Since IL-18 plays a major role in perpetuating hemophagocytosis, the failure of IFNγ to induce IL-18BP may constitute a fundamental pathogenetic mechanism. Furthermore, increased production of IL-8 and IL-27 appears to be associated with this disease. Such dysregulation of cytokines was also found in the heterozygous parents, providing a novel insight into genotype-phenotype correlation of FHL which may encourage future research of this rare disease.
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Affiliation(s)
- Claudia A. Nold-Petry
- Pharmazentrum Frankfurt, Johann Wolfgang Goethe-University Hospital, Frankfurt, Germany
- Division of Infectious Diseases, University of Colorado Denver, Aurora, Colorado, United States of America
| | - Thomas Lehrnbecher
- Department of Pediatrics, Johann Wolfgang Goethe-University Hospital, Frankfurt, Germany
| | - Andrea Jarisch
- Department of Pediatrics, Johann Wolfgang Goethe-University Hospital, Frankfurt, Germany
| | - Dirk Schwabe
- Department of Pediatrics, Johann Wolfgang Goethe-University Hospital, Frankfurt, Germany
| | | | - Heiko Muhl
- Pharmazentrum Frankfurt, Johann Wolfgang Goethe-University Hospital, Frankfurt, Germany
| | - Marcel F. Nold
- Pharmazentrum Frankfurt, Johann Wolfgang Goethe-University Hospital, Frankfurt, Germany
- Division of Infectious Diseases, University of Colorado Denver, Aurora, Colorado, United States of America
- * E-mail:
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Abstract
PURPOSE OF REVIEW Hemophagocytic lymphohistiocytoses represent a rare but biologically and clinically important group of disorders. This review focuses on the clinical, pathophysiologic and genetic manifestations of these disorders along with critical aspects of timely and appropriate treatment. RECENT FINDINGS Detailed laboratory investigations have led to significant advances in our understanding of the molecular and pathophysiologic features of hemophagocytic lymphohistiocytoses. These studies have provided new diagnostic tools and potential new therapeutic targets for future development. Parallel to these laboratory studies have been enormous advances in the treatment and improved clinical outcomes of patients with both primary and secondary hemophagocytic lymphohistiocytoses. The eventual merging of the improved understanding of the molecular pathway with novel gene therapy approaches may prove to be the final frontier in the optimal curative treatment of these disorders. SUMMARY Several key molecular events have been defined which lead to a final common etiologic pathway of natural killer cell dysfunction leading to the hemophagocytic lymphohistiocytosis syndromes. In part through international clinical trials, effective curative therapies for about half of patients with severe forms of hemophagocytic lymphohistiocytosis have been developed. Although a significant advance, the fact that about 50% of patients are still not able to be cured with currently used approaches challenges physician-scientists to develop more innovative and effective diagnostic and therapeutic approaches.
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