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Simpson BN, Mejía Sang ME, Collado Puello Y, Diaz Brockmans EJ, Díaz Soto MF, Rivera Defilló SM, Taveras Cruz KM, Santiago Pérez JO, Husami A, Day ME, Pilipenko V, Mena R, Mota C, Hostetter MK, Muglia LJ, Schlaudecker E, Gonzalez Del Rey J, Martin LJ, Prada CE. The 2019-2020 dengue fever epidemic: genomic markers indicating severity in Dominican Republic children. J Pediatric Infect Dis Soc 2022; 12:169-172. [PMID: 36537278 DOI: 10.1093/jpids/piac136] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022]
Abstract
We performed an observational cohort study to assess associations between genetic factors of dengue fever (DF) severity in children in the Dominican Republic. 488 participants had serologically confirmed DF. We replicated the association between IFIH1 gene (rs1990760) and severe DF (n=80/488, p=0.006) and identified novel associations needing further investigation.
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Affiliation(s)
- Brittany N Simpson
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.,Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States of America, USA
| | - Miguel E Mejía Sang
- Instituto Tecnológico de Santo Domingo, School of Medicine, Santo Domingo, Dominican Republic
| | - Yonairy Collado Puello
- Instituto Tecnológico de Santo Domingo, School of Medicine, Santo Domingo, Dominican Republic
| | | | - María F Díaz Soto
- Instituto Tecnológico de Santo Domingo, School of Medicine, Santo Domingo, Dominican Republic
| | | | - Karla M Taveras Cruz
- Instituto Tecnológico de Santo Domingo, School of Medicine, Santo Domingo, Dominican Republic
| | - Javier O Santiago Pérez
- Instituto Tecnológico de Santo Domingo, School of Medicine, Santo Domingo, Dominican Republic
| | - Ammar Husami
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Melissa E Day
- , Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Valentina Pilipenko
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Rafael Mena
- Centro de Obstetricia y Ginecología, Santo Domingo, Dominican Republic
| | - Cesár Mota
- Pediatric Emergency Medicine Department, Hospital Infantil Dr. Robert Reid, Santo Domingo, Dominican Republic
| | - Margaret K Hostetter
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States of America, USA
| | - Louis J Muglia
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.,Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States of America, USA.,Burroughs Welcome Fund, Research Triangle Park, NC, USA
| | - Elizabeth Schlaudecker
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States of America, USA.,Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Javier Gonzalez Del Rey
- Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States of America, USA.,Division of Pediatric Emergency Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Lisa J Martin
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.,Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States of America, USA
| | - Carlos E Prada
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.,Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States of America, USA.,Division of Genetics, Genomics & Metabolism, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA.,Department of Pediatrics, Feinberg School of Medicine of Northwestern University, Chicago, IL, USA
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2
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Burns AM, Moore DJ, Forster CS, Powell W, Thammasitboon S, Hostetter MK, Weiss P, Boyer D, Ward MA, Blankenburg R, Heyman MB, Rassbach CE, McPhillips H, French A, Nguyen S, Byrne BJ, Parsons DW, Gonzalez F, Nowalk AJ, Ho J, Kumar S, Orange JS, Ackerman KG. Physician-Scientist Training and Programming in Pediatric Residency Programs: A National Survey. J Pediatr 2022; 241:5-9.e3. [PMID: 34280401 DOI: 10.1016/j.jpeds.2021.07.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 07/09/2021] [Indexed: 11/30/2022]
Affiliation(s)
- Audrea M Burns
- Center for Research Innovation and Scholarship in Medical Education, Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, TX.
| | - Daniel J Moore
- Department of Pediatrics, Monroe Carell Jr. Children's Hospital, Ian Burr Division of Pediatric Endocrinology and Diabetes, Nashville, TN
| | - Catherine S Forster
- Department of Pediatrics, University of Pittsburgh School of Medicine, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA
| | - Weston Powell
- Department of Pediatrics, University of Washington School of Medicine, Seattle Children's Hospital, Seattle, WA
| | - Satid Thammasitboon
- Center for Research Innovation and Scholarship in Medical Education, Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
| | | | - Pnina Weiss
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT
| | - Debra Boyer
- Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Mark A Ward
- Center for Research Innovation and Scholarship in Medical Education, Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
| | - Rebecca Blankenburg
- Department of Pediatrics, Stanford University School of Medicine/Stanford Children's Hospital, Palo Alto, CA
| | - Melvin B Heyman
- Department of Pediatrics, School of Medicine, UCSF Benioff Children's Hospital, University California San Francisco, San Francisco, CA
| | - Caroline E Rassbach
- Department of Pediatrics, Stanford University School of Medicine/Stanford Children's Hospital, Palo Alto, CA
| | - Heather McPhillips
- Department of Pediatrics, University of Washington School of Medicine, Seattle Children's Hospital, Seattle, WA
| | - Anthony French
- Department of Pediatrics, Washington University Medical Center, St. Louis Children's Hospital, St Louis, MO
| | - Suong Nguyen
- Department of Pediatrics, Washington University Medical Center, St. Louis Children's Hospital, St Louis, MO
| | - Bobbi J Byrne
- Department of Pediatrics, Riley Hospital for Children at Indiana University Health, Indiana University School of Medicine, Indianapolis, IN
| | - Donald Williams Parsons
- Center for Research Innovation and Scholarship in Medical Education, Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
| | - Fernando Gonzalez
- Department of Pediatrics, School of Medicine, UCSF Benioff Children's Hospital, University California San Francisco, San Francisco, CA
| | - Andrew J Nowalk
- Department of Pediatrics, University of Pittsburgh School of Medicine, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA
| | - Jacqueline Ho
- Department of Pediatrics, University of Pittsburgh School of Medicine, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA
| | - Shelley Kumar
- Center for Research Innovation and Scholarship in Medical Education, Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, TX
| | - Jordan S Orange
- Department of Pediatrics, New York-Presbyterian/Morgan Stanley Children's Hospital, Vagelos College of Physicians and Surgeons, New York, NY
| | - Kate G Ackerman
- Department of Pediatrics, University of Rochester/UR Medicine Golisano Children's Hospital, Rochester, NY
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Barrett KJ, Cooley TM, Schwartz AL, Hostetter MK, Clapp DW, Permar SR. Addressing Gaps in Pediatric Scientist Development: The Department Chair View of 2 AMSPDC-Sponsored Programs. J Pediatr 2020; 222:7-12.e4. [PMID: 32586535 PMCID: PMC8852247 DOI: 10.1016/j.jpeds.2020.01.054] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 01/24/2020] [Indexed: 11/20/2022]
Abstract
Pediatric physician-scientists are important members of the biomedical workforce who are instrumental in translating research advances into novel patient treatment strategies, yet their numbers have been declining over the past four decades. In order to increase the pipeline of pediatric physician-scientists, the Association of Medical School Pediatric Department Chairs (AMSPDC) leads the Frontiers in Science (FIS) and Pediatric Scientist Development Program (PSDP). These programs provide mentorship, networking, and funding opportunities for pediatric residents and fellows who are interested in pursuing research careers. To assess perceptions of program accessibility and efficacy, FIS and PSDP leadership surveyed AMSPDC membership between November 2018 and April 2019; 66 active department chairs responded. The decline in pediatric physician-scientists was identified as a common concern, and responding chairs identified several individual and institutional barriers to the physician-scientist career pathway and to participation in FIS and PSDP. Common barriers to participation included: undefined career paths for physician-scientists, a limited number of FIS slots annually, a perception that these programs support primarily basic science rather than other types of research, and competing funding through institutional T32 and K12 programs. To address these barriers, FIS and PSDP leadership will work with AMSPDC to explore ways to increase access to FIS, promote PSDP alumni mentoring of participating residents and fellows, and expand the scope of research supported by these programs. Assessments of FIS and PSDP will be ongoing, with the goal of improving program access in order to increase and diversify the pediatric physician-scientist workforce.
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Affiliation(s)
| | - T Michelle Cooley
- Office of Physician-Scientist Development, Duke University School of Medicine, Durham, NC
| | - Alan L Schwartz
- Department of Pediatrics, Washington University School of Medicine in St Louis, St Louis, MO
| | - Margaret K Hostetter
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH
| | - D Wade Clapp
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN.
| | - Sallie R Permar
- Department of Pediatrics, Duke University School of Medicine, Durham, NC; Office of Physician-Scientist Development, Duke University School of Medicine, Durham, NC
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4
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Affiliation(s)
- Margaret K Hostetter
- Cincinnati Children's Hospital Medical Center, Department of Pediatrics, University of Cincinnati College of Medicine, OH.
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Dermody TS, Hirsch R, Hostetter MK, Orange JS, St Geme JW. Expanding the Pipeline for Pediatric Physician-Scientists. J Pediatr 2019; 207:3-7.e1. [PMID: 30922503 DOI: 10.1016/j.jpeds.2019.01.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 01/10/2019] [Indexed: 11/17/2022]
Affiliation(s)
- Terence S Dermody
- Departments of Pediatrics and Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, PA
| | - Raphael Hirsch
- Stead Family Department of Pediatrics, University of Iowa Carver College of Medicine, Iowa City, IA
| | - Margaret K Hostetter
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Jordan S Orange
- Department of Pediatrics, Columbia University College of Physicians and Surgeons, Morgan Stanley Children's Hospital, New York, NY
| | - Joseph W St Geme
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Children's Hospital of Philadelphia, Philadelphia, PA.
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7
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Wikenheiser-Brokamp KA, Klein M, Hershey GKK, Devarajan P, DeWitt TG, Loch J, Strauss AW, Muglia LJ, Hostetter MK. Evaluation of Fellows' CrossTalk Effectiveness in Promoting Transdisciplinary Networking and Research. J Pediatr 2017; 181:5-6.e3. [PMID: 27839701 DOI: 10.1016/j.jpeds.2016.10.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kathryn A Wikenheiser-Brokamp
- Division of Pathology and Perinatal Institute Division of Pulmonary Biology, Department of Pathology & Laboratory Medicine.
| | - Melissa Klein
- Division of General and Community Pediatrics, Department of Pediatrics
| | | | - Prasad Devarajan
- Division of Nephrology and Hypertension, Department of Pediatrics
| | - Thomas G DeWitt
- Division of General and Community Pediatrics, Department of Pediatrics
| | - Jill Loch
- Office of Pediatric Clinical Fellowships, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | | | | | - Margaret K Hostetter
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
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8
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Affiliation(s)
- K A Nath
- Department of Medicine, University of Minnesota, Minneapolis
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9
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Patel ZH, Kottyan LC, Lazaro S, Williams MS, Ledbetter DH, Tromp H, Rupert A, Kohram M, Wagner M, Husami A, Qian Y, Valencia CA, Zhang K, Hostetter MK, Harley JB, Kaufman KM. The struggle to find reliable results in exome sequencing data: filtering out Mendelian errors. Front Genet 2014; 5:16. [PMID: 24575121 PMCID: PMC3921572 DOI: 10.3389/fgene.2014.00016] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 01/16/2014] [Indexed: 12/30/2022] Open
Abstract
Next Generation Sequencing studies generate a large quantity of genetic data in a relatively cost and time efficient manner and provide an unprecedented opportunity to identify candidate causative variants that lead to disease phenotypes. A challenge to these studies is the generation of sequencing artifacts by current technologies. To identify and characterize the properties that distinguish false positive variants from true variants, we sequenced a child and both parents (one trio) using DNA isolated from three sources (blood, buccal cells, and saliva). The trio strategy allowed us to identify variants in the proband that could not have been inherited from the parents (Mendelian errors) and would most likely indicate sequencing artifacts. Quality control measurements were examined and three measurements were found to identify the greatest number of Mendelian errors. These included read depth, genotype quality score, and alternate allele ratio. Filtering the variants on these measurements removed ~95% of the Mendelian errors while retaining 80% of the called variants. These filters were applied independently. After filtering, the concordance between identical samples isolated from different sources was 99.99% as compared to 87% before filtering. This high concordance suggests that different sources of DNA can be used in trio studies without affecting the ability to identify causative polymorphisms. To facilitate analysis of next generation sequencing data, we developed the Cincinnati Analytical Suite for Sequencing Informatics (CASSI) to store sequencing files, metadata (eg. relatedness information), file versioning, data filtering, variant annotation, and identify candidate causative polymorphisms that follow either de novo, rare recessive homozygous or compound heterozygous inheritance models. We conclude the data cleaning process improves the signal to noise ratio in terms of variants and facilitates the identification of candidate disease causative polymorphisms.
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Affiliation(s)
- Zubin H Patel
- Division of Rheumatology, Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA ; Medical Scientist Training Program, University of Cincinnati College of Medicine, Cincinnati OH, USA
| | - Leah C Kottyan
- Division of Rheumatology, Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA ; Department of Veterans Affairs, Veterans Affairs Medical Center - Cincinnati, Cincinnati OH, USA
| | - Sara Lazaro
- Division of Rheumatology, Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA ; Department of Veterans Affairs, Veterans Affairs Medical Center - Cincinnati, Cincinnati OH, USA
| | - Marc S Williams
- Genomic Medicine Institute, Geisinger Health System, Danville PA, USA
| | - David H Ledbetter
- Genomic Medicine Institute, Geisinger Health System, Danville PA, USA
| | - Hbgerard Tromp
- Genomic Medicine Institute, Geisinger Health System, Danville PA, USA
| | - Andrew Rupert
- Division of Biomedical Informatics, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA
| | - Mojtaba Kohram
- Division of Biomedical Informatics, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA
| | - Michael Wagner
- Division of Biomedical Informatics, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA
| | - Ammar Husami
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA
| | - Yaping Qian
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA
| | - C Alexander Valencia
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA
| | - Kejian Zhang
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA
| | - Margaret K Hostetter
- Division of Infectious Disease, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA
| | - John B Harley
- Division of Rheumatology, Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA ; Department of Veterans Affairs, Veterans Affairs Medical Center - Cincinnati, Cincinnati OH, USA
| | - Kenneth M Kaufman
- Division of Rheumatology, Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA ; Department of Veterans Affairs, Veterans Affairs Medical Center - Cincinnati, Cincinnati OH, USA
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Green JV, Orsborn KI, Zhang M, Tan QKG, Greis KD, Porollo A, Andes DR, Long Lu J, Hostetter MK. Heparin-binding motifs and biofilm formation by Candida albicans. J Infect Dis 2013; 208:1695-704. [PMID: 23904295 PMCID: PMC4038792 DOI: 10.1093/infdis/jit391] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 05/30/2013] [Indexed: 01/02/2023] Open
Abstract
Candida albicans is a leading pathogen in infections of central venous catheters, which are frequently infused with heparin. Binding of C. albicans to medically relevant concentrations of soluble and plate-bound heparin was demonstrable by confocal microscopy and enzyme-linked immunosorbent assay (ELISA). A sequence-based search identified 34 C. albicans surface proteins containing ≥1 match to linear heparin-binding motifs. The virulence factor Int1 contained the most putative heparin-binding motifs (n = 5); peptides encompassing 2 of 5 motifs bound to heparin-Sepharose. Alanine substitution of lysine residues K805/K806 in 804QKKHQIHK811 (motif 1 of Int1) markedly attenuated biofilm formation in central venous catheters in rats, whereas alanine substitution of K1595/R1596 in 1593FKKRFFKL1600 (motif 4 of Int1) did not impair biofilm formation. Affinity-purified immunoglobulin G (IgG) recognizing motif 1 abolished biofilm formation in central venous catheters; preimmune IgG had no effect. After heparin treatment of C. albicans, soluble peptides from multiple C. albicans surface proteins were detected, such as Eno1, Pgk1, Tdh3, and Ssa1/2 but not Int1, suggesting that heparin changes candidal surface structures and may modify some antigens critical for immune recognition. These studies define a new mechanism of biofilm formation for C. albicans and a novel strategy for inhibiting catheter-associated biofilms.
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Affiliation(s)
- Margaret K Hostetter
- Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
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Abstract
By inhibiting the conversion of 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) to mevalonate, statins impair cholesterol metabolism in humans. We reasoned that statins might similarly interfere with the biosynthesis of ergosterol, the major sterol of the yeast cell membrane. As assessed by spectrophotometric and microscopic analysis, significant inhibition of biofilm production was noted after 16-h incubation with 1, 2.5, and 5 muM simvastatin, concentrations that did not affect growth, adhesion, or hyphal formation by C. albicans in vitro. Higher concentrations (10, 20, and 25 muM simvastatin) inhibited biofilm by >90% but also impaired growth. Addition of exogenous ergosterol (90 muM) overcame the effects of 1 and 2.5 muM simvastatin, suggesting that at least one mechanism of inhibition is interference with ergosterol biosynthesis. Clinical isolates from blood, skin, and mucosal surfaces produced biofilms; biofilms from bloodstream isolates were similarly inhibited by simvastatin. In the absence of fungicidal activity, simvastatin's interruption of a critical step in an essential metabolic pathway, highly conserved from yeast to man, has unexpected effects on biofilm production by a eukaryotic pathogen.
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Affiliation(s)
- Geoffrey Liu
- Department of Pediatrics, Yale School of Medicine, New Haven, Connecticut 06520, USA
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Abstract
On the basis of biochemical and immunologic studies, a receptor for iC3b with some activities reminiscent of the integrins CD11b and CD11c was defined on the cell wall of clinical and laboratory isolates of Candida albicans. The INT1 gene encodes a protein of 1659 amino acids; the Int1 protein participates in adhesion to epithelial cells in vitro and in vivo. Int1 is essential for hyphal morphogenesis and virulence in a murine model. Recent evidence points to the amino terminus of Int1 as the source of a peptide, Pep263, with superantigen-like activities.
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Affiliation(s)
- Margaret K Hostetter
- Department of Pediatrics, Yale School of Medicine, 333 Cedar Street, LMP 4085, P.O. Box 208064, New Haven, CT 06520-8064, USA.
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Devore-Carter D, Kar S, Vellucci V, Bhattacherjee V, Domanski P, Hostetter MK. Superantigen-like effects of a Candida albicans polypeptide. J Infect Dis 2008; 197:981-9. [PMID: 18419534 DOI: 10.1086/529203] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The amino terminal sequence of the Candida albicans cell wall protein Int1 exhibited partial identity with the major histocompatibility complex (MHC) class II binding site of the Mycoplasma arthritidis superantigen MAM. Int1-positive C. albicans blastospores activated human T lymphocytes and expanded Vbeta subsets 2, 3, and/or 14; Int1-negative strains were inactive. Release of interferon-gamma (IFN-gamma) but not of tumor necrosis factor-alpha or interleukin-6 was Int1 dependent; interleukin-4 and interleukin-10 were not detected. T lymphocyte activation, Vbeta expansion, and IFN-gamma release were associated with a soluble polypeptide that encompassed the first 263 amino acids of Int1 (Pep(263)). Monoclonal antibody 163.5, which recognizes an Int1 epitope that overlaps the region of identity with MAM, significantly inhibited these activities when triggered by Int1-positive blastospores or Pep(263) but not by staphylococcal enterotoxin B. Histidine(263) was required. Pep(263) bound to T lymphocytes and MHC class II and was detected in the urine of a patient with C. albicans fungemia. These studies identify a candidal protein that displays superantigen-like activities.
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Affiliation(s)
- Denise Devore-Carter
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06520-8064, USA
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Frank CF, Hostetter MK. Cleavage of E-cadherin: a mechanism for disruption of the intestinal epithelial barrier by Candida albicans. Transl Res 2007; 149:211-22. [PMID: 17383595 DOI: 10.1016/j.trsl.2006.11.006] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2006] [Revised: 11/10/2006] [Accepted: 11/22/2006] [Indexed: 11/21/2022]
Abstract
To investigate how intestinal epithelial cells respond to contact with Candida albicans, an organism able to invade the bloodstream via the gastrointestinal tract, we focused on the junction proteins occludin, E-cadherin, and desmoglein-2. The levels of these 3 junction proteins were reduced in lysates of human intestinal epithelial monolayers (Caco-2) after a 24-h inoculation with C. albicans, compared with lysates from Saccharomyces cerevisiae-inoculated monolayers. Treatment with pepstatin A did not change the effect of C. albicans on full-length occludin, desmoglein-2, and E-cadherin; however, pepstatin A enhanced the accumulation of a 35-kDa fragment derived from the intracellular portion of E-cadherin. This 35-kDa fragment also accumulated in the presence of gamma-secretase inhibitors. These observations suggest that enhancement of E-cadherin cleavage by C. albicans generates an intracellular E-cadherin fragment that can serve as a substrate for gamma-secretase. An 89-kDa extracellular fragment of E-cadherin was detected in supernatants of C. albicans-inoculated monolayers; this cleavage event was insensitive to both pepstatin A and gamma-secretase inhibitors. Transepithelial electrical resistance, a measure of monolayer integrity, decreased significantly and synchronously with increased generation of the 89-kDa extracellular E-cadherin fragment. Cleavage of E-cadherin may destabilize the homotypic interactions between adjacent epithelial cells and could contribute to loss of monolayer integrity. These experiments identify 2 E-cadherin cleavage events that are enhanced by contact with C. albicans: an intracellular cleavage event that generates a substrate for gamma-secretase and an extracellular cleavage event that is temporally associated with an increase in monolayer permeability.
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Affiliation(s)
- Charlotte F Frank
- Department of Microbiology, Yale University, New Haven, CT 06520, USA
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F.Vellucci V, Gygax S, Hostetter MK. Involvement of Candida albicans pyruvate dehydrogenase complex protein X (Pdx1) in filamentation. Fungal Genet Biol 2006; 44:979-90. [PMID: 17254815 PMCID: PMC2062515 DOI: 10.1016/j.fgb.2006.12.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Revised: 12/05/2006] [Accepted: 12/06/2006] [Indexed: 11/29/2022]
Abstract
For 50 years, physiologic studies in Candida albicans have associated fermentation with filamentation and respiration with yeast morphology. Analysis of the mitochondrial proteome of a C. albicans NDH51 mutant, known to be defective in filamentation, identified increased expression of several proteins in the respiratory pathway. Most notable was a 15-fold increase in pyruvate dehydrogenase complex protein X (Pdx1), an essential component of the pyruvate dehydrogenase complex. In basal salts medium with < or = 100 mM glucose as carbon source, two independent pdx1 mutants displayed a filamentation defect identical to ndh51; reintegration of one PDX1 allele restored filamentation. Concentrations of glucose < or = 100 mM did not correct the filamentation defect. Expanding on previous work, these studies suggest that increased expression of proteins extraneous to the electron transport chain compensates for defects in the respiratory pathway to maintain yeast morphology. Mitochondrial proteomics can aid in the identification of C. albicans genes not previously implicated in filamentation.
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Affiliation(s)
- Vincent F.Vellucci
- Department of Pediatrics and Program in Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06520
| | - Scott Gygax
- Antimicrobial Resistance Section, Molecular and Cellular Biology Division, Research and Development Department, Medical Diagnostic Laboratories, L.L.C. Hamilton, NJ 08690-3303
| | - Margaret K. Hostetter
- Department of Pediatrics and Program in Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06520
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18
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Affiliation(s)
- Margaret K Hostetter
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520-8064, USA.
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Abstract
Many internationally adopted children have a pre-adoption video for prospective adoptive parents to review before their commitment to adopt. No published report to date has examined the value of the pre-adoption video evaluation (PreAVE) as a predictor of post-adoption developmental status. The present study was designed to determine whether PreAVE can predict the post-adoption developmental status of internationally adopted children. In this retrospective chart review, children who presented to the Yale International Adoption Clinic between December 1998 and September 2000, and had both a PreAVE and a post-adoption developmental evaluation (PosADE) were selected (N = 20) PreAVE was done using the Denver II and PosADE was done using the Bayley Scales of Infant Development, 2nd edition. The Pearson r coefficient between the two ratings was determined and sensitivity and specificity were calculated. There was a significant correlation between the PreAVE and the PosADEs (r = 0.53, p = 0.01).The sensitivity of PreAVE to detect moderate to severe developmental delay was 43% and the specificity was 85%. Although ratings of development on PreAVE are similar to PosADE, the ability to detect moderate to severe developmental delay by video review is limited.
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Affiliation(s)
- Jon L Boone
- Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06520-8064, USA
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22
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Abstract
The gene encoding the 51-kDa subunit of nicotinamide adenine dinucleotide (NADH) dehydrogenase complex I, a principal component of the mitochondrial electron transport chain, was cloned in Candida tropicalis. The homolog in C. albicans, CaNDH51, was identified, and each allele was successively disrupted by PCR-mediated gene disruption. Wild type, heterozygote, reintegrant, and homozygous null mutants grew as blastoconidia in rich medium containing 3% glucose, but the homozygous null mutant failed to grow in ethanol or acetate. When glucose concentration was varied from 1 mM (0.018%) to 200 mM (3.6%) in a basal salts medium, all strains grew equally well at all glucose concentrations; the wild-type strain, the heterozygote, and the reintegrant exhibited abundant germ tubes, pseudohyphae, and hyphae. In contrast, the ndh51/ndh51 strain failed to display any type of filamentous growth, even in glucose concentrations as low as 1 mM. These results suggest a previously unexplored relationship between mitochondrial electron transport and morphogenesis.
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Affiliation(s)
- Justin A McDonough
- Department of Pediatrics and Center for Microbial Pathogenesis, Yale University School of Medicine, 464 Congress Avenue, New Haven, CT 06519, USA
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23
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24
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Pearson HA, Hostetter MK, Friedman AH. Pediatric grand rounds: a tribute to Norman J. Siegel, M.D. Yale J Biol Med 2002; 75:307-12. [PMID: 14580112 PMCID: PMC2588813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
At ceremonies held in Baltimore Maryland on May, 4, 2002, Dr. Howard A Pearson, Professor of Pediatrics, was awarded the John A. Howland award of the American Pediatric Society, probably the most prestigious award of American Pediatrics. Dr. Pearson had been nominated for the award by Dr. Norman Siegel. The Department of Pediatrics Grand Rounds on Wednesday noon, October 26, 2002 was originally scheduled as a repetition of the presentation by Dr. Siegel and the acceptance by Dr. Pearson for those who could not be in Baltimore. However; in a number of meetings, unknown to Dr. Siegel, it was unanimously decided that it would be very appropriate to instead honor him as he stepped down from his position as Vice- and Interim Chairman of Pediatrics, and to formally thank him for his long and faithful service to the Department of Pediatrics, the Yale University School of Medicine, and the Yale New Haven Hospital.
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Affiliation(s)
- Howard A Pearson
- Department of Pediatrics, Yale School of Medicine, New Haven, Connecticut 06520, USA
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25
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Zhang Y, Masi AW, Barniak V, Mountzouros K, Hostetter MK, Green BA. Recombinant PhpA protein, a unique histidine motif-containing protein from Streptococcus pneumoniae, protects mice against intranasal pneumococcal challenge. Infect Immun 2001; 69:3827-36. [PMID: 11349048 PMCID: PMC98401 DOI: 10.1128/iai.69.6.3827-3836.2001] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The multivalent pneumococcal conjugate vaccine is effective against both systemic disease and otitis media caused by serotypes contained in the vaccine. However, serotypes not covered by the current conjugate vaccine may still cause pneumococcal disease. To address these serotypes and the remaining otitis media due to Streptococcus pneumoniae, we have been evaluating antigenically conserved proteins from S. pneumoniae as vaccine candidates. A previous report identified a 20-kDa protein with putative human complement C3-proteolytic activity. By utilizing the publicly released pneumococcal genomic sequences, we found the gene encoding the 20-kDa protein to be part of a putative open reading frame of approximately 2,400 bp. We recombinantly expressed a 79-kDa fragment (rPhpA-79) that contains a repeated HxxHxH motif and evaluated it for vaccine potential. The antibodies elicited by the purified rPhpA-79 protein were cross-reactive to proteins from multiple strains of S. pneumoniae and were against surface-exposed epitopes. Immunization with rPhpA-79 protein adjuvanted with monophosphoryl lipid A (for subcutaneous immunization) or a mutant cholera toxin, CT-E29H (for intranasal immunization), protected CBA/N mice against death and bacteremia, as well as reduced nasopharyngeal colonization, following intranasal challenge with a heterologous pneumococcal strain. In contrast, immunization with the 20-kDa portion of the PhpA protein did not protect mice. These results suggest that rPhpA-79 is a potential candidate for use as a vaccine against pneumococcal systemic disease and otitis media.
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Affiliation(s)
- Y Zhang
- Department of Immunology, Wyeth Lederle Vaccines, West Henrietta, New York 14586-9728, USA.
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26
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San-Blas G, Travassos LR, Fries BC, Goldman DL, Casadevall A, Carmona AK, Barros TF, Puccia R, Hostetter MK, Shanks SG, Copping VM, Knox Y, Gow NA. Fungal morphogenesis and virulence. Med Mycol 2001; 38 Suppl 1:79-86. [PMID: 11204167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
Phenotypic variability in pathogenic fungi has long been correlated with virulence, but specific genetic and molecular mechanisms are only recently being unraveled. Fungal morphogenesis, reflecting the expression of several regulated genes, and the capacity of the rising forms or phases to cause disease has been focused on at the XIVth Congress of the International Society for Human and Animal Mycology. Three experimental models of pathogenic fungi have been discussed. In Cryptococcus neoformans, phenotypic variability or switching represents controlled and programmed changes rather than random mutations. Evaluated phenotypic traits were the capsular polysaccharide, cell and colony morphology and virulence. In the dimorphic Paracoccidioides brasiliensis, the serine-thiol proteinase from the yeast phase cleaves the main components of the basal membrane, thus being potentially relevant in fungal dissemination. In Candida albicans, relationships between adhesion proteins and those of lymphocytes and neutrophils are related to fungal pathogenicity. Regulation of the directional growth of hyphae and its tropic responses are correlated with the invasive potential of C. albicans.
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Affiliation(s)
- G San-Blas
- Instituto Venezolano de Investigaciones Científicas, Centro de Microbiología y Biología Celular, Caracas, Venezuela.
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27
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Abstract
The ability of choline-binding protein A (CbpA) of Streptococcus pneumoniae to bind the third component of complement (C3) suggests possible interactions with opsonic C3 in the bloodstream or with C3 secreted by epithelial cells. The latter possibility was investigated by measuring C3 in supernatants of resting and cytokine-activated monolayers of type II pulmonary epithelial cells (A549 cells). Expression of C3 on the epithelial cell surface was confirmed by immunofluorescence. Epithelially produced C3 bound to CbpA, as determined by Western blot test. cbpa(-) mutants and lysates therefrom failed to bind C3, were completely deficient in adhesion to a matrix in which C3 was the sole substrate, and demonstrated a moderate yet significant decrease in adhesion to type II pulmonary epithelial cells. These results confirm the interaction of the pneumococcal protein CbpA and its substrate, C3, in 2 in vitro models of adhesion.
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Affiliation(s)
- B L Smith
- Department of Pediatrics, Division of Infectious Diseases, and Department of Microbiology, Immunology and Molecular Pathobiology, University of Minnesota, Minneapolis, USA
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28
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Abstract
Progress in the understanding of fungal adhesion has led to the identification of novel proteins recognizing the RGD tripeptide in matrix proteins and to the characterization of what appears to be an emerging subset of fungal adhesins that themselves contain an RGD sequence.
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Affiliation(s)
- M K Hostetter
- Yale Child Health Research Center, Yale University School of Medicine, New Haven, Connecticut 06519, USA.
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29
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Abstract
To isolate microbial proteins capable of binding the third component of complement (C3), we coupled the free sulfhydryl group of methylamine-inactivated C3 to a thiolSepharose matrix. This simple technique facilitated the purification of the first C3-binding protein isolated from a bacterium (Streptococcus pneumoniae). Both metastable (native) and thioester-disrupted C3 were recognized by this protein; binding of C3 was noncovalent, independent of thioester conformation, and preferential for the C3 alpha-chain. Sequencing of amino-terminal and internal peptides from the C3-binding protein disclosed a proline-rich region spanning approximately 20 amino acids and a signal peptide that had not been previously reported. The gene was isolated from a library of genomic DNA from laboratory strain CP1200 by screening with a 1200 bp PCR product amplified from degenerate oligonucleotides encoding the amino terminal sequence and the internal proline-rich sequence. The open reading frame spanned 1692 bp; all peptide sequences were identified in the translated gene product, which also contained at least three choline-binding repeats at the carboxy-terminus. The gene was conserved, and the translated protein was functionally active in pneumococcal clinical isolates of serotypes 1, 3, 4, 14, and 19F. Serum from a patient recovering from acute pneumococcal infection contained IgG antibodies specific for this protein by immunoblot. Wide conservation among clinical isolates, saturable binding of C3, and the ability to stimulate the human immune response have not previously been reported for this choline-binding protein. A similar biochemical approach should enable the identification of other C3-binding proteins in microorganisms able to elude complement-mediated host defense.
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Affiliation(s)
- Q Cheng
- Yale Child Health Research Center, Yale University School of Medicine, 464 Congress Avenue, New Haven, Connecticut 06520-8081, USA
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Madsen M, Lebenthal Y, Cheng Q, Smith BL, Hostetter MK. A pneumococcal protein that elicits interleukin-8 from pulmonary epithelial cells. J Infect Dis 2000; 181:1330-6. [PMID: 10762564 DOI: 10.1086/315388] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/1999] [Revised: 12/09/1999] [Indexed: 11/03/2022] Open
Abstract
To understand how neutrophils are recruited to the lung in pneumococcal pneumonia, the ability of pneumococcal components to elicit the chemokine interleukin (IL)-8 from monolayers of cultured human type II cells was assessed. Heat-killed clinical and laboratory strains of Streptococcus pneumoniae and secreted proteins from exponentially growing pneumococci elicited significant quantities of IL-8 from A549 cells. All strains that elicited IL-8 production secreted a protein ( approximately 90 kDa) that comigrated on SDS-PAGE with a C3-binding protein previously identified in S. pneumoniae. As little as 7 pmol of the purified 90-kDa protein readily elicited levels of IL-8 production equivalent to those obtained with 1 U of IL-1alpha. Supernatant proteins and heat-killed cells of an isogenic mutant that failed to produce the C3-binding protein elicited significantly less IL-8 than did supernatant proteins or heat-killed cells of the parent strain. These results implicate the C3-binding protein of S. pneumoniae in a novel pathway of pulmonary inflammation.
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Affiliation(s)
- M Madsen
- Divisions of Critical Care Medicine, Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN, USA
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31
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Affiliation(s)
- M K Hostetter
- Department of Pediatrics, Yale Child Health Research Center, New Haven, CT 06520, USA.
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32
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Abstract
The vertebrate integrins provide a paradigm for cell surface proteins involved in adhesion and morphogenesis. However, homologs of integrins have been found in more primitive organisms. This review will discuss the evidence for surface proteins in Candida albicans and Candida tropicalis that contain motifs reminiscent of integrins and will analyze the contributions of one of these proteins, Int1p, to adhesion, morphogenesis, and virulence. Other microorganisms thought to express integrin-like proteins will also be addressed.
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Affiliation(s)
- M K Hostetter
- Yale University School of Medicine, 464 Congress Avenue, New Haven, Connecticut 06519, USA
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33
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Kinneberg KM, Bendel CM, Jechorek RP, Cebelinski EA, Gale CA, Berman JG, Erlandsen SL, Hostetter MK, Wells CL. Effect of INT1 gene on Candida albicans murine intestinal colonization. J Surg Res 1999; 87:245-51. [PMID: 10600356 DOI: 10.1006/jsre.1999.5755] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Increased intestinal colonization with Candida albicans is believed to be a major factor predisposing immunocompromised and postsurgical patients to systemic candidiasis, although the mechanisms facilitating C. albicans colonization remain unclear. Because previous studies have linked the C. albicans INT1 gene to filament formation, epithelial adherence, and mouse virulence, experiments were designed to evaluate the effect of INT1 on intestinal colonization. MATERIALS AND METHODS Mice were orally inoculated with either the parent strain (CAF2, INT/INT1), an int1 heterozygote (CAG1, INT1/int1), an int1 homozygote (CAG3, int1/int1), or a reintegrant (CAG5, int1/int1 + INT1), and sacrificed 3 and 7 days later for quantitative analysis of cecal C. albicans. RESULTS Following oral inoculation with 10(3) C. albicans, only small numbers of each strain were recovered from the cecal flora of normal mice. However, in mice pretreated with oral antibiotics, cecal colonization of each strain was increased (P < 0.01). In addition, cecal colonization was reduced for all int1 mutant strains compared with the parent strain (P < 0.05). By light microscopy, all four C. albicans strains were easily observed in the ileal lumen as both budding yeast and filamentous forms, although only occasional yeast forms appeared adherent to the intestinal epithelium. CONCLUSIONS C. albicans readily colonized and replicated in the ceca of antibiotic-treated mice. The presence of two functional copies of INT1 appeared to facilitate C. albicans cecal colonization, suggesting that intestinal colonization may be another virulence factor associated with INT1 and that the gene product may be an attractive target to control C. albicans intestinal colonization.
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Affiliation(s)
- K M Kinneberg
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis 55455, USA
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34
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Bendel CM, Kinneberg KM, Jechorek RP, Gale CA, Erlandsen SL, Hostetter MK, Wells CL. Systemic infection following intravenous inoculation of mice with Candida albicans int1 mutant strains. Mol Genet Metab 1999; 67:343-51. [PMID: 10444345 DOI: 10.1006/mgme.1999.2875] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Candida albicans gene INT1 is associated with epithelial adhesion, hyphal formation, and virulence. C. albicans strains carrying two, one, or no functional INT1 alleles were used to assess the association between mortality and C. albicans persistence in the liver and kidney of intravenously inoculated mice. Mice were injected with 10(5) C. albicans CAF2 (parent strain, INT1/INT1), C. albicans CAG3 (homozygous disruptant, Int1/int1), or C. albicans CAG5 (heterozygous reintegrant, int1/int1 + INT1). Mortality was monitored and mice were sacrificed on Days 1, 7, 14, and 21 for quantitative analysis of kidney and liver microbes, with histologic analysis of these tissues as well. Mortality was highest for mice injected with the wild-type strain CAF2 (INT1/INT1) and lowest for mice injected with the homozygous disruptant CAG3 (int/int1). Yeast were readily cleared from the liver of all mice injected with any of the three C. albicans strains. Although the mutant strains CAG3 and CAG5 are defective for hyphal formation in vitro, there was histological evidence of abundant hyphal formation in the renal pelvis of mice injected with these strains. Compared to the wild-type strain, mutant strains were associated with reduced mortality but increased C. albicans persistence in the kidney. Thus, the absolute ability to form hyphae in the kidney did not appear to modulate either C. albicans-induced mortality or the course of progressive infection in the kidney. In addition, reduced virulence was paradoxically associated with increased, not decreased, persistence of C. albicans in the kidney.
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Affiliation(s)
- C M Bendel
- Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota 55455-0385, USA.
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35
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Affiliation(s)
- M K Hostetter
- Section of Immunology, Yale University Child Health Research Center, New Haven, CT, USA
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36
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Hostetter MK. Infectious diseases in internationally adopted children: findings in children from China, Russia, and eastern Europe. Adv Pediatr Infect Dis 1999; 14:147-61. [PMID: 10079853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Conditions in many orphanages provide a fertile environment for infectious diseases uncommonly encountered in industrialized nations. Moreover, health care providers may be unfamiliar with the need to test for these conditions in internationally adopted children. Pediatric infectious disease specialists provide much-needed expertise for parents and providers alike.
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Affiliation(s)
- M K Hostetter
- Yale University School of Medicine, New Haven, Connecticut, USA
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37
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Affiliation(s)
- M K Hostetter
- Department of Pediatrics, University of Minnesota, Minneapolis, USA
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38
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39
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Gale CA, Bendel CM, McClellan M, Hauser M, Becker JM, Berman J, Hostetter MK. Linkage of adhesion, filamentous growth, and virulence in Candida albicans to a single gene, INT1. Science 1998; 279:1355-8. [PMID: 9478896 DOI: 10.1126/science.279.5355.1355] [Citation(s) in RCA: 247] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Adhesion and the ability to form filaments are thought to contribute to the pathogenicity of Candida albicans, the leading cause of fungal disease in immunocompromised patients. Int1p is a C. albicans surface protein with limited similarity to vertebrate integrins. INT1 expression in Saccharomyces cerevisiae was sufficient to direct the adhesion of this normally nonadherent yeast to human epithelial cells. Furthermore, disruption of INT1 in C. albicans suppressed hyphal growth, adhesion to epithelial cells, and virulence in mice. Thus, INT1 links adhesion, filamentous growth, and pathogenicity in C. albicans and Int1p may be an attractive target for the development of antifungal therapies.
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Affiliation(s)
- C A Gale
- Department of Pediatrics, University of Minnesota, 420 Delaware Street S.E., Minneapolis, MN 55455, USA
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40
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Albers LH, Johnson DE, Hostetter MK, Iverson S, Miller LC. Health of children adopted from the former Soviet Union and Eastern Europe. Comparison with preadoptive medical records. JAMA 1997; 278:922-4. [PMID: 9302245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
CONTEXT Children born in the countries of the former Soviet Union and Eastern Europe are now a main source of international adoptions in the United States, but often little information is available about these children prior to adoption. OBJECTIVE To analyze the preadoptive medical reports of children adopted from Eastern Europe and the former Soviet Union and to compare these reports with their evaluations after arrival in the United States. DESIGN Case series. SUBJECTS AND SETTING A total of 56 children adopted from Eastern Europe and the former Soviet Union were evaluated in 2 international adoption clinics. Preadoptive medical records were available for 47 of these children. RESULTS There were 43 (91%) of 47 medical reports available from the children's birth countries that included multiple unfamiliar neurologic diagnoses. Evaluations in the International Adoption Clinics frequently revealed growth delays (zscore < or = -1 for weight in 44% of children, height in 68%, and head circumference in 43%). Children had 1 month of linear growth lag for every 5 months in an orphanage (r=-0.48, P<.001). Developmental delays were also common (gross motor delays in 70% of children, fine motor in 82%, language in 59%, and social-emotional in 53%). While serious medical problems were found or corroborated in 11 (20%) of the 56 children evaluated in our clinics, neurologic diagnoses cited in preadoptive medical reports were not confirmed. CONCLUSIONS Preadoptive medical records from these international adoptees included multiple diagnoses suggesting severe neurologic impairment. Although these diagnoses were not confirmed when the children were evaluated in the United States, substantial growth and developmental delays were identified.
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Affiliation(s)
- L H Albers
- International Adoption Clinics at the Floating Hospital for Children, Tufts-New England Medical Center, Boston, MA 02111, USA
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41
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Affiliation(s)
- J C Salazar
- Department of Pediatrics, University of Minnesota School of Medicine, Minneapolis, USA
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42
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Hostetter MK. Steadfast in the 'steady state'. Arch Pediatr Adolesc Med 1996; 150:897-8. [PMID: 8790117 DOI: 10.1001/archpedi.1996.02170340011002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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43
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Abstract
The binding of Candida tropicalis to fibronectin (FN) was studied in order to characterize the FN receptor in this species. FN binding was saturable at a concentration of 1.8 x 10(-9) M and exhibited a Kd of 2.3 x 10(-9) M and a receptor density of 854 receptors per cell. Extracts of C. tropicalis cell membrane at dilutions of 1:100-1:1000 significantly inhibited the binding of 3H-labeled FN to C. tropicalis cells (P < .03). Purified FN, antibodies to the integrin alpha 5 beta 1 (FN receptor on human placenta), and antibodies specific for the integrin beta 1 subunit recognized a C. tropicalis membrane protein of 125 +/- 25 kDa on immunoblots. Immunoprecipitation of radiolabeled proteins from C. tropicalis with purified human FN yielded a protein of 105 +/- 15 kDa. Thus, C. tropicalis expresses a protein with antigenic and functional similarity to the vertebrate beta 1 integrin FN receptor.
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Affiliation(s)
- G P DeMuri
- Department of Pediatrics, University of Minnesota, Minneapolis, USA
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44
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Abstract
Candida albicans is the foremost fungal pathogen in neonates, diabetics and immunocompromised people. The discovery of integrin-like proteins in this yeast and the involvement of these proteins in adhesion, morphogenesis and signal transduction suggest important roles for primitive integrins in the pathogenesis of infectious diseases, and as paradigms for signaling and differentiation in vertebrate cells.
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Affiliation(s)
- M K Hostetter
- Dept of Pediatrics, University of Minnesota, Minneapolis 55455, USA.
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45
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Hostetter MK, Johnson D. Medical examination of the internationally adopted child: screening for infectious diseases and developmental delay. Postgrad Med 1996; 99:70-2, 75-7, 81-2. [PMID: 8604416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Because of the number of internationally adopted children with undiagnosed disease, a defined set of screening tests for medical evaluation is now recommended. By and large, these tests are directed toward infectious diseases that are more common abroad than in the United States. In this article, the authors examine various aspects of screening and highlight tests that are useful in children from specified areas. They also review developmental issues that are of prime importance to these children and their new families.
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Affiliation(s)
- M K Hostetter
- Division of Infectious Diseases, University of Minnesota Hospital and Clinic, Minneapolis, USA
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46
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Affiliation(s)
- M K Hostetter
- Department of Pediatrics, University of Minnesota, Minneapolis 55455, USA
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47
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Hostetter MK. New insights into candidal infections. Adv Pediatr 1996; 43:209-30. [PMID: 8794178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- M K Hostetter
- Division of Infectious Diseases, University of Minnesota Hospital and Clinic, Minneapolis, USA
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48
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Abstract
Five very low birth weight infants developed systemic Candida albicans infection during a 6-week period in an urban neonatal intensive care unit. In an effort to assess whether a common source outbreak was present, the genomic DNA of the clinical isolates was compared by EcoRI and XbaI restriction fragment analysis and Southern blot hybridization with 27A, a species-specific, transposon-like probe. Although the restriction fragment analysis suggested strong similarities among the isolates, the hybridization patterns demonstrated that all strains were genotypically distinct. The parallel use of at least two restriction enzymes was important for differentiating the isolates. Rapid genotypic analysis of clinical isolates from a cluster of C. albicans infections permits determination of whether a common source is probable, facilitates epidemiologic decisions and may reduce infection control measures and attendant costs.
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Affiliation(s)
- R G Faix
- Department of Pediatrics, University of Michigan, Ann Arbor, USA
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49
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Hostetter MK, Tao NJ, Gale C, Herman DJ, McClellan M, Sharp RL, Kendrick KE. Antigenic and functional conservation of an integrin I-domain in Saccharomyces cerevisiae. Biochem Mol Med 1995; 55:122-30. [PMID: 7582869 DOI: 10.1006/bmme.1995.1042] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We sought evidence for precursors of the leukocyte integrin subunits alpha M and alpha X among unicellular eukaryotes such as Saccharomyces cerevisiae. Chromatography of cytosolic extracts of Saccharomyces cerevisiae on an affinity matrix coupled to BU-15, a monoclonal antibody that recognizes alpha X, revealed a band of M(r) > 205 kDa under nonreducing conditions. Screening a lambda gt11 library of S. cerevisiae DNA with BU-15 (anti-alpha X) and anti-Mo1 (anti-alpha M) led to the isolation of a 3.7-kb EcoRI fragment containing the 3' end of an open reading frame sufficient to encode a polypeptide in excess of 118 kDa. On the basis of Southern blotting at high stringency, this gene was present in S. cerevisiae, but not in other yeast species such as Candida glabrata. Analysis of the derived amino acid sequence demonstrated > 98% identity with the S. cerevisiae protein Uso1p, a myosin-like polypeptide found exclusively in the cytosol. The C-terminal 1016 aa, expressed from the 3.7-kb EcoRI fragment in Escherichia coli as a beta-galactosidase fusion protein, bound iC3b, a ligand for the I-domain in alpha M and alpha X, and were recognized by Mn41, a monoclonal antibody specific for the alpha M I-domain. Antigenic and functional conservation of an I-domain in S. cerevisiae suggests that this domain may be a prototype for integrin-like proteins in other primitive eukaryotes.
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Affiliation(s)
- M K Hostetter
- Department of Pediatrics, University of Minnesota, Minneapolis 55455, USA
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50
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Abstract
The marked increase in the number of patients with AIDS and other forms of immunocompromise has resulted in the emergence of fungi as predominant pathogens in many institutions. Unfortunately, with the widespread use of antifungal agents to combat these infections, reports of resistance to antifungal agents have proliferated. In the present environment, the occurrence of resistance to antifungal agents is neither rare nor of negligible clinical importance. The expanding demand for antifungal agents mandates a new sense of vigilance for resistance. Although newly proposed standards for in vitro susceptibility testing should help to remove the ambiguity surrounding quantitative measurement of fungal resistance, lessons learned in the treatment of bacteria clearly now apply to fungi also: prolonged use of an antimicrobial agent will result in the selection of resistant organisms. The enlarging spectrum of resistance to antifungal agents must prompt aggressive searches for new modes of therapy. Strategies to inhibit fungal colonization, to augment host defenses, or to develop novel antifungal agents from Pseudomonas syringae or from peptide nanotubes are helping to solve this pressing clinical need.
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Affiliation(s)
- G P DeMuri
- Department of Pediatrics, University of Minnesota, Minneapolis, USA
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