1
|
Huang J, Osthushenrich T, MacNamara A, Mälarstig A, Brocchetti S, Bradberry S, Scarabottolo L, Ferrada E, Sosnin S, Digles D, Superti-Furga G, Ecker GF. ProteoMutaMetrics: machine learning approaches for solute carrier family 6 mutation pathogenicity prediction. RSC Adv 2024; 14:13083-13094. [PMID: 38655474 PMCID: PMC11034476 DOI: 10.1039/d4ra00748d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 03/25/2024] [Indexed: 04/26/2024] Open
Abstract
The solute carrier transporter family 6 (SLC6) is of key interest for their critical role in the transport of small amino acids or amino acid-like molecules. Their dysfunction is strongly associated with human diseases such as including schizophrenia, depression, and Parkinson's disease. Linking single point mutations to disease may support insights into the structure-function relationship of these transporters. This work aimed to develop a computational model for predicting the potential pathogenic effect of single point mutations in the SLC6 family. Missense mutation data was retrieved from UniProt, LitVar, and ClinVar, covering multiple protein-coding transcripts. As encoding approach, amino acid descriptors were used to calculate the average sequence properties for both original and mutated sequences. In addition to the full-sequence calculation, the sequences were cut into twelve domains. The domains are defined according to the transmembrane domains of the SLC6 transporters to analyse the regions' contributions to the pathogenicity prediction. Subsequently, several classification models, namely Support Vector Machine (SVM), Logistic Regression (LR), Random Forest (RF), and Extreme Gradient Boosting (XGBoost) with the hyperparameters optimized through grid search were built. For estimation of model performance, repeated stratified k-fold cross-validation was used. The accuracy values of the generated models are in the range of 0.72 to 0.80. Analysis of feature importance indicates that mutations in distinct regions of SLC6 transporters are associated with an increased risk for pathogenicity. When applying the model on an independent validation set, the performance in accuracy dropped to averagely 0.6 with high precision but low sensitivity scores.
Collapse
Affiliation(s)
- Jiahui Huang
- University of Vienna, Department of Pharmaceutical Sciences Vienna Austria
| | - Tanja Osthushenrich
- Bayer AG, Division Pharmaceuticals, Biomedical Data Science II Wuppertal Germany
| | - Aidan MacNamara
- Bayer AG, Division Pharmaceuticals, Biomedical Data Science II Wuppertal Germany
| | - Anders Mälarstig
- Emerging Science & Innovation, Pfizer Worldwide Research, Development and Medical Cambridge MA USA
| | | | | | | | - Evandro Ferrada
- CeMM, Research Center for Molecular Medicine of the Austrian Academy of Sciences Vienna Austria
| | - Sergey Sosnin
- University of Vienna, Department of Pharmaceutical Sciences Vienna Austria
| | - Daniela Digles
- University of Vienna, Department of Pharmaceutical Sciences Vienna Austria
| | - Giulio Superti-Furga
- CeMM, Research Center for Molecular Medicine of the Austrian Academy of Sciences Vienna Austria
| | - Gerhard F Ecker
- University of Vienna, Department of Pharmaceutical Sciences Vienna Austria
| |
Collapse
|
2
|
Ferrada E, Wiedmer T, Wang WA, Frommelt F, Steurer B, Klimek C, Lindinger S, Osthushenrich T, Garofoli A, Brocchetti S, Bradberry S, Huang J, MacNamara A, Scarabottolo L, Ecker GF, Malarstig A, Superti-Furga G. Experimental and Computational Analysis of Newly Identified Pathogenic Mutations in the Creatine Transporter SLC6A8. J Mol Biol 2024; 436:168383. [PMID: 38070861 DOI: 10.1016/j.jmb.2023.168383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 11/26/2023] [Accepted: 12/01/2023] [Indexed: 12/24/2023]
Abstract
Creatine is an essential metabolite for the storage and rapid supply of energy in muscle and nerve cells. In humans, impaired metabolism, transport, and distribution of creatine throughout tissues can cause varying forms of mental disability, also known as creatine deficiency syndrome (CDS). So far, 80 mutations in the creatine transporter (SLC6A8) have been associated to CDS. To better understand the effect of human genetic variants on the physiology of SLC6A8 and their possible impact on CDS, we studied 30 missense variants including 15 variants of unknown significance, two of which are reported here for the first time. We expressed these variants in HEK293 cells and explored their subcellular localization and transport activity. We also applied computational methods to predict variant effect and estimate site-specific changes in thermodynamic stability. To explore variants that might have a differential effect on the transporter's conformers along the transport cycle, we constructed homology models of the inward facing, and outward facing conformations. In addition, we used mass-spectrometry to study proteins that interact with wild type SLC6A8 and five selected variants in HEK293 cells. In silico models of the protein complexes revealed how two variants impact the interaction interface of SLC6A8 with other proteins and how pathogenic variants lead to an enrichment of ER protein partners. Overall, our integrated analysis disambiguates the pathogenicity of 15 variants of unknown significance revealing diverse mechanisms of pathogenicity, including two previously unreported variants obtained from patients suffering from the creatine deficiency syndrome.
Collapse
Affiliation(s)
- Evandro Ferrada
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.
| | - Tabea Wiedmer
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Wen-An Wang
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Fabian Frommelt
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Barbara Steurer
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Christoph Klimek
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Sabrina Lindinger
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | | | - Andrea Garofoli
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | | | | | - Jiahui Huang
- Department of Pharmaceutical Sciences, University of Vienna, Vienna, Austria
| | | | | | - Gerhard F Ecker
- Department of Pharmaceutical Sciences, University of Vienna, Vienna, Austria
| | - Anders Malarstig
- Pfizer Worldwide Research, Development and Medical, Stockholm, Sweden
| | - Giulio Superti-Furga
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria; Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria.
| |
Collapse
|
3
|
Thanaj M, Mielke J, McGurk KA, Bai W, Savioli N, de Marvao A, Meyer HV, Zeng L, Sohler F, Lumbers RT, Wilkins MR, Ware JS, Bender C, Rueckert D, MacNamara A, Freitag DF, O'Regan DP. Genetic and environmental determinants of diastolic heart function. Nat Cardiovasc Res 2022; 1:361-371. [PMID: 35479509 PMCID: PMC7612636 DOI: 10.1038/s44161-022-00048-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Diastole is the sequence of physiological events that occur in the heart during ventricular filling and principally depends on myocardial relaxation and chamber stiffness. Abnormal diastolic function is related to many cardiovascular disease processes and is predictive of health outcomes, but its genetic architecture is largely unknown. Here, we use machine learning cardiac motion analysis to measure diastolic functional traits in 39,559 participants of the UK Biobank and perform a genome-wide association study. We identified 9 significant, independent loci near genes that are associated with maintaining sarcomeric function under biomechanical stress and genes implicated in the development of cardiomyopathy. Age, sex and diabetes were independent predictors of diastolic function and we found a causal relationship between genetically-determined ventricular stiffness and incident heart failure. Our results provide insights into the genetic and environmental factors influencing diastolic function that are relevant for identifying causal relationships and potential tractable targets.
Collapse
Affiliation(s)
- Marjola Thanaj
- MRC London Institute of Medical Sciences, Imperial College London, London, UK
| | - Johanna Mielke
- Bayer AG, Research & Development, Pharmaceuticals, Wuppertal, Germany
| | - Kathryn A McGurk
- MRC London Institute of Medical Sciences, Imperial College London, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - Wenjia Bai
- Department of Computing, Imperial College London, London, UK.,Department of Brain Sciences, Imperial College London
| | - Nicolò Savioli
- MRC London Institute of Medical Sciences, Imperial College London, London, UK.,Department of Computing, Imperial College London, London, UK
| | - Antonio de Marvao
- MRC London Institute of Medical Sciences, Imperial College London, London, UK
| | - Hannah V Meyer
- Cold Spring Harbor Laboratory, Simons Center for Quantitative Biology, USA
| | - Lingyao Zeng
- Bayer AG, Research & Development, Pharmaceuticals, Wuppertal, Germany
| | - Florian Sohler
- Bayer AG, Research & Development, Pharmaceuticals, Wuppertal, Germany
| | | | - Martin R Wilkins
- National Heart and Lung Institute, Imperial College London, London, UK
| | - James S Ware
- MRC London Institute of Medical Sciences, Imperial College London, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - Christian Bender
- Bayer AG, Research & Development, Pharmaceuticals, Wuppertal, Germany
| | - Daniel Rueckert
- Department of Computing, Imperial College London, London, UK.,Institute for Artificial Intelligence and Informatics, Klinikum rechts der Isar, Technical University of Munich, Germany
| | - Aidan MacNamara
- Bayer AG, Research & Development, Pharmaceuticals, Wuppertal, Germany
| | - Daniel F Freitag
- Bayer AG, Research & Development, Pharmaceuticals, Wuppertal, Germany
| | - Declan P O'Regan
- MRC London Institute of Medical Sciences, Imperial College London, London, UK
| |
Collapse
|
4
|
MacNamara A, Nakic N, Amin Al Olama A, Guo C, Sieber KB, Hurle MR, Gutteridge A. Network and pathway expansion of genetic disease associations identifies successful drug targets. Sci Rep 2020; 10:20970. [PMID: 33262371 PMCID: PMC7708424 DOI: 10.1038/s41598-020-77847-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 11/06/2020] [Indexed: 11/24/2022] Open
Abstract
Genetic evidence of disease association has often been used as a basis for selecting of drug targets for complex common diseases. Likewise, the propagation of genetic evidence through gene or protein interaction networks has been shown to accurately infer novel disease associations at genes for which no direct genetic evidence can be observed. However, an empirical test of the utility of combining these approaches for drug discovery has been lacking. In this study, we examine genetic associations arising from an analysis of 648 UK Biobank GWAS and evaluate whether targets identified as proxies of direct genetic hits are enriched for successful drug targets, as measured by historical clinical trial data. We find that protein networks formed from specific functional linkages such as protein complexes and ligand–receptor pairs are suitable for even naïve guilt-by-association network propagation approaches. In addition, more sophisticated approaches applied to global protein–protein interaction networks and pathway databases, also successfully retrieve targets enriched for clinically successful drug targets. We conclude that network propagation of genetic evidence can be used for drug target identification.
Collapse
Affiliation(s)
| | | | | | - Cong Guo
- Human Genetics, GSK, Collegeville, PA, USA
| | | | | | | |
Collapse
|
5
|
Zeng X, MacNamara A, Xie Q, Lu Q, Hou W, Rao Y, Maratuo K, Rea C, Madsen H, Larminie C. A systematic approach integrating genetics, computational biology, chemical genomics and gene editing to identify novel targets in the Type I interferon signaling pathway for autoimmune and infectious diseases. The Journal of Immunology 2018. [DOI: 10.4049/jimmunol.200.supp.170.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Abstract
The type I interferon (IFN a/b) signaling pathway plays a critical role in microbial host defense, including mediating the interaction between innate and adaptive immunity. A growing body of evidence suggests that IFN is aberrantly regulated in human autoimmune diseases and chronic infections, such as Systematic Lupus Erythematosus, HIV infection and the rare Mendelian diseases, Aicardi-Goutier Syndrome and the Singleton Merton Syndrome (also called “interferonopathies”). This has raised significant interest in exploring the cellular signaling associated with type I IFNs for potential targets for autoimmunity and infectious disease. In this study, we systematically interrogated the type I IFN signaling pathway to identify and validate potential therapeutic targets based on the following workflow: 1. Perform computational biology analysis using genetics, interaction networks and gene expression in human diseases to generate a list of targets that have an association with increased type I IFN. 2. Establish the THP-1 cell-based type I IFNbeta release assay to screen a focused set of target annotated tool compounds. 3. Integrate the inferred targets from the tool compound hits into the in-silico network analysis. 4. Generate a short list of targets (10–20) with high confidence to perform CRISPR analysis in THP-1 cells. 5. Generate a long list of targets (~200) to perform a pooled CRISPR screen using single cell technology and reporter-based flow sorting and enrichment. Here we present validation data on a few representative targets and a summary of the outcomes and learning from this study.
Collapse
|
6
|
Abstract
Cell signaling pathways control cells' responses to their environment through an intricate network of proteins and small molecules partitioned by intracellular structures, such as the cytoskeleton and nucleus. Our understanding of these pathways has been revised recently with the advent of more advanced experimental techniques; no longer are signaling pathways viewed as linear cascades of information flowing from membrane-bound receptors to the nucleus. Instead, such pathways must be understood in the context of networks, and studying such networks requires an integration of computational and experimental approaches. This understanding is becoming more important in designing novel therapies for diseases such as cancer. Using the MAPK (mitogen-activated protein kinase) and PI3K (class I phosphoinositide-3' kinase) pathways as case studies of cellular signaling, we give an overview of these pathways and their functions. We then describe, using a number of case studies, how computational modeling has aided in understanding these pathways' deregulation in cancer, and how such understanding can be used to optimally tailor current therapies or help design new therapies against cancer.
Collapse
Affiliation(s)
- Julio Saez-Rodriguez
- Current address: Joint Research Center for Computational Biomedicine, RWTH Aachen University Hospital, D-52074 Aachen, Germany;
- European Bioinformatics Institute, European Molecular Biology Laboratory, Wellcome Trust Genome Campus, Hinxton, Cambridgeshire CB10 1SD, United Kingdom;
| | - Aidan MacNamara
- European Bioinformatics Institute, European Molecular Biology Laboratory, Wellcome Trust Genome Campus, Hinxton, Cambridgeshire CB10 1SD, United Kingdom;
| | - Simon Cook
- Signalling Laboratory, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, United Kingdom;
| |
Collapse
|
7
|
Feng S, Laketa V, Stein F, Rutkowska A, MacNamara A, Depner S, Klingmüller U, Saez-Rodriguez J, Schultz C. A rapidly reversible chemical dimerizer system to study lipid signaling in living cells. Angew Chem Int Ed Engl 2014; 53:6720-3. [PMID: 24841150 DOI: 10.1002/anie.201402294] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Indexed: 01/11/2023]
Abstract
Chemical dimerizers are powerful tools for non-invasive manipulation of enzyme activities in intact cells. Here we introduce the first rapidly reversible small-molecule-based dimerization system and demonstrate a sufficiently fast switch-off to determine kinetics of lipid metabolizing enzymes in living cells. We applied this new method to induce and stop phosphatidylinositol 3-kinase (PI3K) activity, allowing us to quantitatively measure the turnover of phosphatidylinositol 3,4,5-trisphosphate (PIP3) and its downstream effectors by confocal fluorescence microscopy as well as standard biochemical methods.
Collapse
Affiliation(s)
- Suihan Feng
- Cell Biology & Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg (Germany)
| | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Feng S, Laketa V, Stein F, Rutkowska A, MacNamara A, Depner S, Klingmüller U, Saez-Rodriguez J, Schultz C. A Rapidly Reversible Chemical Dimerizer System to Study Lipid Signaling in Living Cells. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201402294] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
9
|
Egea JA, Henriques D, Cokelaer T, Villaverde AF, MacNamara A, Danciu DP, Banga JR, Saez-Rodriguez J. MEIGO: an open-source software suite based on metaheuristics for global optimization in systems biology and bioinformatics. BMC Bioinformatics 2014; 15:136. [PMID: 24885957 PMCID: PMC4025564 DOI: 10.1186/1471-2105-15-136] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 04/24/2014] [Indexed: 11/28/2022] Open
Abstract
Background Optimization is the key to solving many problems in computational biology. Global optimization methods, which provide a robust methodology, and metaheuristics in particular have proven to be the most efficient methods for many applications. Despite their utility, there is a limited availability of metaheuristic tools. Results We present MEIGO, an R and Matlab optimization toolbox (also available in Python via a wrapper of the R version), that implements metaheuristics capable of solving diverse problems arising in systems biology and bioinformatics. The toolbox includes the enhanced scatter search method (eSS) for continuous nonlinear programming (cNLP) and mixed-integer programming (MINLP) problems, and variable neighborhood search (VNS) for Integer Programming (IP) problems. Additionally, the R version includes BayesFit for parameter estimation by Bayesian inference. The eSS and VNS methods can be run on a single-thread or in parallel using a cooperative strategy. The code is supplied under GPLv3 and is available at http://www.iim.csic.es/~gingproc/meigo.html. Documentation and examples are included. The R package has been submitted to BioConductor. We evaluate MEIGO against optimization benchmarks, and illustrate its applicability to a series of case studies in bioinformatics and systems biology where it outperforms other state-of-the-art methods. Conclusions MEIGO provides a free, open-source platform for optimization that can be applied to multiple domains of systems biology and bioinformatics. It includes efficient state of the art metaheuristics, and its open and modular structure allows the addition of further methods.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Julio R Banga
- (Bio)Process Engineering Group, Spanish National Research Council, IIM-CSIC, 36208 Vigo, Spain.
| | | |
Collapse
|
10
|
Laketa V, Zarbakhsh S, Traynor-Kaplan A, MacNamara A, Subramanian D, Putyrski M, Mueller R, Nadler A, Mentel M, Saez-Rodriguez J, Pepperkok R, Schultz C. PIP3 Induces the Recycling of Receptor Tyrosine Kinases. Sci Signal 2014; 7:ra5. [DOI: 10.1126/scisignal.2004532] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
11
|
Twigger K, Rowan A, Seich al Basatena NK, MacNamara A, Retiere C, Gould K, Taylor GP, Asquith B, Bangham CRM. Frequency and function of KIR+ CD8+ T cells in HTLV-1 infection. Retrovirology 2014. [PMCID: PMC4044156 DOI: 10.1186/1742-4690-11-s1-p79] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
|
12
|
Terfve C, Cokelaer T, Henriques D, MacNamara A, Goncalves E, Morris MK, van Iersel M, Lauffenburger DA, Saez-Rodriguez J. CellNOptR: a flexible toolkit to train protein signaling networks to data using multiple logic formalisms. BMC Syst Biol 2012; 6:133. [PMID: 23079107 PMCID: PMC3605281 DOI: 10.1186/1752-0509-6-133] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 09/19/2012] [Indexed: 12/17/2022]
Abstract
Background Cells process signals using complex and dynamic networks. Studying how this is performed in a context and cell type specific way is essential to understand signaling both in physiological and diseased situations. Context-specific medium/high throughput proteomic data measured upon perturbation is now relatively easy to obtain but formalisms that can take advantage of these features to build models of signaling are still comparatively scarce. Results Here we present CellNOptR, an open-source R software package for building predictive logic models of signaling networks by training networks derived from prior knowledge to signaling (typically phosphoproteomic) data. CellNOptR features different logic formalisms, from Boolean models to differential equations, in a common framework. These different logic model representations accommodate state and time values with increasing levels of detail. We provide in addition an interface via Cytoscape (CytoCopteR) to facilitate use and integration with Cytoscape network-based capabilities. Conclusions Models generated with this pipeline have two key features. First, they are constrained by prior knowledge about the network but trained to data. They are therefore context and cell line specific, which results in enhanced predictive and mechanistic insights. Second, they can be built using different logic formalisms depending on the richness of the available data. Models built with CellNOptR are useful tools to understand how signals are processed by cells and how this is altered in disease. They can be used to predict the effect of perturbations (individual or in combinations), and potentially to engineer therapies that have differential effects/side effects depending on the cell type or context.
Collapse
Affiliation(s)
- Camille Terfve
- European Bioinformatics Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SD, UK
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Schmidt J, MacNamara A, Hajcak G, Zelinsky G. A neural marker of the representation used to guide visual search. J Vis 2012. [DOI: 10.1167/12.9.729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
|
14
|
Abstract
Despite the current wealth of high-throughput data, our understanding of signal transduction is still incomplete. Mathematical modeling can be a tool to gain an insight into such processes. Detailed biochemical modeling provides deep understanding, but does not scale well above relatively a few proteins. In contrast, logic modeling can be used where the biochemical knowledge of the system is sparse and, because it is parameter free (or, at most, uses relatively a few parameters), it scales well to large networks that can be derived by manual curation or retrieved from public databases. Here, we present an overview of logic modeling formalisms in the context of training logic models to data, and specifically the different approaches to modeling qualitative to quantitative data (state) and dynamics (time) of signal transduction. We use a toy model of signal transduction to illustrate how different logic formalisms (Boolean, fuzzy logic and differential equations) treat state and time. Different formalisms allow for different features of the data to be captured, at the cost of extra requirements in terms of computational power and data quality and quantity. Through this demonstration, the assumptions behind each formalism are discussed, as well as their advantages and disadvantages and possible future developments.
Collapse
Affiliation(s)
- Aidan MacNamara
- European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Cambridge CB10 1SD, UK
| | | | | | | | | |
Collapse
|
15
|
O'Connor GM, Seich Al Basatena NK, Olavarria V, MacNamara A, Vine A, Ying Q, Hisada M, Galvão-Castro B, Asquith B, McVicar DW. In contrast to HIV, KIR3DS1 does not influence outcome in HTLV-1 retroviral infection. Hum Immunol 2012; 73:783-7. [PMID: 22609443 DOI: 10.1016/j.humimm.2012.05.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 04/30/2012] [Accepted: 05/08/2012] [Indexed: 12/14/2022]
Abstract
While most carriers of human T-cell leukemia virus type 1 (HTLV-1) remain asymptomatic throughout their lifetime, infection is associated with the development of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The exact parameters that determine these outcomes are unknown but are believed to include host genetic factors that control the immune response to infection. Host response to fellow retroviridae member HIV is influenced by the expression of members of the Killer Immunoglobulin Receptor (KIR) family including KIR3DS1. In this study we examined the association of KIR3DS1 with the outcome of HTLV-1 infection in three geographically distinct cohorts (Jamaican, Japanese and Brazilian). Despite increased prevalence of KIR3DS1 in the HAM/TSP patients of the Jamaican cohort, we found no evidence for a role of KIR3DS1 in influencing control of proviral load or disease outcome. This suggests that unlike HIV, KIR3DS1-mediated regulation of HTLV-1 infection does not occur, or is ineffective.
Collapse
Affiliation(s)
- Geraldine M O'Connor
- Cancer and Inflammation Program, Laboratory of Experimental Immunology, NCI-Frederick, Frederick, MD 21702, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Algar LA, MacNamara A. An investigation of the support required for development of high performance swimmers. Br J Sports Med 2011. [DOI: 10.1136/bjsports-2011-090606.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
17
|
Best I, López G, Talledo M, MacNamara A, Verdonck K, González E, Tipismana M, Asquith B, Gotuzzo E, Vanham G, Clark D. Short communication an interferon-γ ELISPOT assay with two cytotoxic T cell epitopes derived from HTLV-1 tax region 161-233 discriminates HTLV-1-associated myelopathy/tropical spastic paraparesis patients from asymptomatic HTLV-1 carriers in a Peruvian population. AIDS Res Hum Retroviruses 2011; 27:1207-12. [PMID: 21453202 DOI: 10.1089/aid.2011.0029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic and progressive disorder caused by the human T-lymphotropic virus type 1 (HTLV-1). In HTLV-1 infection, a strong cytotoxic T cell (CTL) response is mounted against the immunodominant protein Tax. Previous studies carried out by our group reported that increased IFN-γ enzyme-linked immunospot (ELISPOT) responses against the region spanning amino acids 161 to 233 of the Tax protein were associated with HAM/TSP and increased HTLV-1 proviral load (PVL). An exploratory study was conducted on 16 subjects with HAM/TSP, 13 asymptomatic carriers (AC), and 10 HTLV-1-seronegative controls (SC) to map the HAM/TSP-associated CTL epitopes within Tax region 161-233. The PVL of the infected subjects was determined and the specific CTL response was evaluated with a 6-h incubation IFN-γ ELISPOT assay using peripheral blood mononuclear cells (PBMCs) stimulated with 16 individual overlapping peptides covering the Tax region 161-233. Other proinflammatory and Th1/Th2 cytokines were also quantified in the supernatants by a flow cytometry multiplex assay. In addition, a set of human leukocyte antigen (HLA) class I alleles that bind with high affinity to the CTL epitopes of interest was determined using computational tools. Univariate analyses identified an association between ELISPOT responses to two new CTL epitopes, Tax 173-185 and Tax 181-193, and the presence of HAM/TSP as well as an increased PVL. The HLA-A*6801 allele, which is predicted to bind to the Tax 181-193 peptide, was overpresented in the HAM/TSP patients tested.
Collapse
Affiliation(s)
- Ivan Best
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Giovanni López
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Michael Talledo
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Aidan MacNamara
- Department of Immunology, Imperial College School of Medicine, London, United Kingdom
| | - Kristien Verdonck
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Virology Unit, Department of Microbiology, Institute of Tropical Medicine, Antwerp, Belgium
| | - Elsa González
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Departamento de Medicina, Facultad de Medicina, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Martín Tipismana
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Departamento de Medicina, Facultad de Medicina, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Becca Asquith
- Department of Immunology, Imperial College School of Medicine, London, United Kingdom
| | - Eduardo Gotuzzo
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Departamento de Medicina, Facultad de Medicina, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Guido Vanham
- Virology Unit, Department of Microbiology, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Daniel Clark
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Laboratorios de Investigación y Desarrollo (LID), Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| |
Collapse
|
18
|
Seich al Basatena NK, MacNamara A, Vine AM, Thio CL, Astemborski J, Usuku K, Osame M, Kirk GD, Donfield SM, Goedert JJ, Bangham CR, Carrington M, Khakoo SI, Asquith B. KIR2DL2 enhances protective and detrimental HLA class I-mediated immunity in chronic viral infection. PLoS Pathog 2011; 7:e1002270. [PMID: 22022261 PMCID: PMC3192839 DOI: 10.1371/journal.ppat.1002270] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 08/01/2011] [Indexed: 12/14/2022] Open
Abstract
Killer cell immunoglobulin-like receptors (KIRs) influence both innate and adaptive immunity. But while the role of KIRs in NK-mediated innate immunity is well-documented, the impact of KIRs on the T cell response in human disease is not known. Here we test the hypothesis that an individual's KIR genotype affects the efficiency of their HLA class I-mediated antiviral immune response and the outcome of viral infection. We show that, in two unrelated viral infections, hepatitis C virus and human T lymphotropic virus type 1, possession of the KIR2DL2 gene enhanced both protective and detrimental HLA class I-restricted anti-viral immunity. These results reveal a novel role for inhibitory KIRs. We conclude that inhibitory KIRs, in synergy with T cells, are a major determinant of the outcome of persistent viral infection. Hepatitis C virus (HCV) and human T-cell leukemia virus (HTLV-I) infect millions of people worldwide. Some HCV-infected individuals spontaneously clear the virus and many HTLV-1-infected people remain asymptomatic; however, in both cases the infection can lead to serious illness such as cancer. The factors which determine outcome are still elusive. We have found that a gene that encodes a receptor (KIR2DL2) enhances both protective and detrimental HLA class I-mediated immunity to HCV and HTLV-1. Strikingly, although KIRs are primarily associated with innate immunity, our observations suggest that they also have a major impact on the efficiency of the adaptive immune response. This work helps to explain why one individual infected with a virus remains healthy but another, infected with the same virus develops disease; it also helps to explain why particular HLA class I molecules do not always protect or cause susceptibility as expected. Interestingly, the impact of the KIR is entirely context dependent: if an HLA class I molecule is protective then protection is enhanced, but in the context of a detrimental HLA then susceptibility is enhanced. This study reveals a novel role for inhibitory KIRs in adaptive immunity.
Collapse
MESH Headings
- Female
- Genes, MHC Class I
- HTLV-I Infections/genetics
- HTLV-I Infections/immunology
- HTLV-I Infections/virology
- Hepacivirus/immunology
- Hepacivirus/physiology
- Hepatitis C, Chronic/genetics
- Hepatitis C, Chronic/immunology
- Hepatitis C, Chronic/virology
- Histocompatibility Antigens Class I/immunology
- Human T-lymphotropic virus 1/immunology
- Human T-lymphotropic virus 1/physiology
- Humans
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Killer Cells, Natural/virology
- Male
- Receptors, KIR/immunology
- Receptors, KIR2DL2/genetics
- Receptors, KIR2DL2/metabolism
- T-Lymphocytes/immunology
- Viral Load
Collapse
Affiliation(s)
| | | | | | - Chloe L. Thio
- Johns Hopkins University, Baltimore, Maryland, United States of America
| | | | | | | | - Gregory D. Kirk
- Johns Hopkins University, Baltimore, Maryland, United States of America
| | | | - James J. Goedert
- National Cancer Institute, Rockville, Maryland, United States of America
| | | | - Mary Carrington
- Cancer and Inflammation Program, Laboratory of Experimental Immunology, SAIC-Frederick, Inc., NCI-Frederick, Frederick, Maryland, United States of America
- Ragon Institute of MGH, MIT and Harvard, Boston, Massachusetts, United States of America
| | | | | |
Collapse
|
19
|
Schmidt J, MacNamara A, Hajcak G, Zelinsky G. ERP correlates of the target representation used to guide search. J Vis 2011. [DOI: 10.1167/11.11.1345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
|
20
|
Hilburn S, Rowan A, Demontis MA, MacNamara A, Asquith B, Bangham CRM, Taylor GP. In vivo expression of human T-lymphotropic virus type 1 basic leucine-zipper protein generates specific CD8+ and CD4+ T-lymphocyte responses that correlate with clinical outcome. J Infect Dis 2011; 203:529-36. [PMID: 21208912 DOI: 10.1093/infdis/jiq078] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The roles of the human T-lymphotropic virus type 1 (HTLV-1) basic leucine zipper (HBZ) gene are not clearly understood. We examined CD8+ and CD4+ T cell responses to HBZ and compared these with Tax responses. METHOD Interferon (IFN)-γ and interleukin (IL)-2-secreting T cells were detected by enzyme-linked immunosorbent spot (ELISpot) assays of freshly isolated peripheral blood mononuclear cells (PBMCs) stimulated with synthetic HBZ or Tax peptides. Ten patients with HTLV-1-associated myelopathy (HAM) and 20 asymptomatic HTLV-1 carriers (ACs), (10 high, 10 low viral load). RESULTS Of 30 study participants, 17 had detectable HBZ-specific CD4+ T cells and 12 had HBZ-specific CD8+ T cell responses. Detection of Tax-specific CD4+ T cells (IL-2- or IFN-γ-secreting) did not differ by disease status, but Tax-specific CD8+ T cell responses were more commonly detected in patients with HAM. HBZ-specific CD4+ or CD8+ T cells were less likely to be detected than Tax-specific T cells. IL-2-secreting Tax-specific CD8+ T cells, and IFN-γ-secreting Tax-specific CD4+ T cells were associated with HAM. Low viral load, asymptomatic HTLV-1 carriage was associated with IL-2-secreting CD8+ T cells specific for HBZ. CONCLUSION HBZ protein is expressed in vivo in patients with HAM and in ACs. Our results are consistent with the idea that the T cell response to HBZ plays an important part in restricting HTLV-1 viral load.
Collapse
Affiliation(s)
- Silva Hilburn
- Infectious Diseases, Faculty of Medicine, Imperial College, Norfolk Place, London, England
| | | | | | | | | | | | | |
Collapse
|
21
|
MacNamara A, Rowan A, Hilburn S, Kadolsky U, Fujiwara H, Suemori K, Yasukawa M, Taylor G, Bangham CRM, Asquith B. HLA class I binding of HBZ determines outcome in HTLV-1 infection. PLoS Pathog 2010; 6:e1001117. [PMID: 20886101 PMCID: PMC2944806 DOI: 10.1371/journal.ppat.1001117] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2009] [Accepted: 08/20/2010] [Indexed: 11/19/2022] Open
Abstract
CD8(+) T cells can exert both protective and harmful effects on the virus-infected host. However, there is no systematic method to identify the attributes of a protective CD8(+) T cell response. Here, we combine theory and experiment to identify and quantify the contribution of all HLA class I alleles to host protection against infection with a given pathogen. In 432 HTLV-1-infected individuals we show that individuals with HLA class I alleles that strongly bind the HTLV-1 protein HBZ had a lower proviral load and were more likely to be asymptomatic. We also show that in general, across all HTLV-1 proteins, CD8(+) T cell effectiveness is strongly determined by protein specificity and produce a ranked list of the proteins targeted by the most effective CD8(+) T cell response through to the least effective CD8(+) T cell response. We conclude that CD8(+) T cells play an important role in the control of HTLV-1 and that CD8(+) cells specific to HBZ, not the immunodominant protein Tax, are the most effective. We suggest that HBZ plays a central role in HTLV-1 persistence. This approach is applicable to all pathogens, even where data are sparse, to identify simultaneously the HLA Class I alleles and the epitopes responsible for a protective CD8(+) T cell response.
Collapse
Affiliation(s)
- Aidan MacNamara
- Department of Immunology, Faculty of Medicine, Imperial College, London, United Kingdom
| | - Aileen Rowan
- Department of Immunology, Faculty of Medicine, Imperial College, London, United Kingdom
| | - Silva Hilburn
- Section of Infectious Diseases, Faculty of Medicine, Imperial College, London, United Kingdom
| | - Ulrich Kadolsky
- Department of Immunology, Faculty of Medicine, Imperial College, London, United Kingdom
| | - Hiroshi Fujiwara
- Department of Bioregulatory Medicine, Graduate School of Medicine, Ehime University, and Ehime University Proteomedicine Research Center, Toh-on city, Ehime, Japan
| | - Koichiro Suemori
- Department of Bioregulatory Medicine, Graduate School of Medicine, Ehime University, and Ehime University Proteomedicine Research Center, Toh-on city, Ehime, Japan
| | - Masaki Yasukawa
- Department of Bioregulatory Medicine, Graduate School of Medicine, Ehime University, and Ehime University Proteomedicine Research Center, Toh-on city, Ehime, Japan
| | - Graham Taylor
- Section of Infectious Diseases, Faculty of Medicine, Imperial College, London, United Kingdom
| | - Charles R. M. Bangham
- Department of Immunology, Faculty of Medicine, Imperial College, London, United Kingdom
| | - Becca Asquith
- Department of Immunology, Faculty of Medicine, Imperial College, London, United Kingdom
- * E-mail:
| |
Collapse
|
22
|
Kattan T, MacNamara A, Rowan AG, Nose H, Mosley AJ, Tanaka Y, Taylor GP, Asquith B, Bangham CRM. The avidity and lytic efficiency of the CTL response to HTLV-1. J Immunol 2009; 182:5723-9. [PMID: 19380819 DOI: 10.4049/jimmunol.0900069] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In human T-lymphotropic virus type 1 (HTLV-1) infection, a high frequency of HTLV-1-specific CTLs can co-exist stably with a high proviral load and the proviral load is strongly correlated with the risk of HTLV-1-associated inflammatory diseases. These observations led to the hypothesis that HTLV-1 specific CTLs are ineffective in controlling HTLV-1 replication but contribute to the pathogenesis of the inflammatory diseases. But evidence from host and viral immunogenetics and gene expression microarrays suggests that a strong CTL response is associated with a low proviral load and a low risk of HAM/TSP. Here, we quantified the frequency, lytic activity and functional avidity of HTLV-1-specific CD8(+) cells in fresh, unstimulated PBMCs from individuals with natural HTLV-1 infection. The lytic efficiency of the CD8(+) T cell response-the fraction of autologous HTLV-1-expressing cells eliminated per CD8(+) cell per day-was inversely correlated with both the proviral load and the rate of spontaneous proviral expression. The functional avidity of HTLV-1-specific CD8(+) cells was strongly correlated with their lytic efficiency. We conclude that efficient control of HTLV-1 in vivo depends on the CTL lytic efficiency, which depends in turn on CTL avidity of Ag recognition. CTL quality determines the position of virus-host equilibrium in persistent HTLV-1 infection.
Collapse
Affiliation(s)
- Tarek Kattan
- Department of Immunology, Wright-Fleming Institute, Imperial College London, United Kingdom
| | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Abstract
BACKGROUND The Advanced Life Support (ALS) Provider Course trains healthcare professionals in a standardised approach to the management of a cardiac arrest. In the setting of limited resources for healthcare training, it is important that courses are fit for purpose in addressing the needs of both the individual and healthcare system. This study investigated the use of ALS skills in clinical practice after training on an ALS course amongst members of the cardiac arrest team compared to first responders. METHODS Questionnaires measuring skill use after an ALS course were distributed to 130 doctors and nurses. RESULTS 91 replies were returned. Basic life support, basic airway management, manual defibrillation, rhythm recognition, drug administration, team leadership, peri- and post-arrest management and resuscitation in special circumstances were used significantly more often by cardiac arrest team members than first responders. There was no difference in skill use between medically and nursing qualified first responders or arrest team members. CONCLUSION We believe that the ALS course is more appropriately targeted to members of a cardiac arrest team. In our opinion the recently launched Immediate Life Support course, in parallel with training in the recognition and intervention in the early stages of critical illness, are more appropriate for the occasional or first responder to a cardiac arrest.
Collapse
Affiliation(s)
- Jonathan Hulme
- Intensive Care Unit, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK
| | | | | | | |
Collapse
|
24
|
Perkins GD, Baldock C, Roberts C, MacNamara A. Response to an article by Gwinnutt et al., ‘Outcome after cardiac arrest in adults in UK hospitals — effect of the 1997 guidelines’. Resuscitation 2001. [DOI: 10.1016/s0300-9572(00)00365-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
25
|
Hull A, Haut F, Feldman E, Bingley W, Hassan T, MacNamara A, Bodiwala G. Managing patients with deliberate self harm who refuse treatment in accident and emergency departments. BMJ 1999. [DOI: 10.1136/bmj.319.7214.916] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
26
|
MacNamara A. Cambridge Textbook of Accident and Emergency Medicine. Med Chir Trans 1998. [DOI: 10.1177/014107689809100126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Aidan MacNamara
- Accident and Emergency Department, Leicester Royal Infirmary, Leicester LE1 5WW, UK
| |
Collapse
|
27
|
Abstract
An unusual form of larval infestation from South America is presented which, in view of increasing tourism to South america's tropical areas, may present to any accident and emergency department. Infestation with Dermatobia hominis is reviewed in terms of clinical recognition and life cycle. Techniques of removal are described.
Collapse
Affiliation(s)
- A MacNamara
- Accident and Emergency Department, Leicester Royal Infirmary NHS Trust
| | | |
Collapse
|
28
|
Hassan TB, Durham S, MacNamara A. Pre-hospital ABCs: getting the right message across! J Accid Emerg Med 1995; 12:71-2. [PMID: 7640843 PMCID: PMC1342532 DOI: 10.1136/emj.12.1.71-b] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
|
29
|
Pye SD, Wild SR, McDicken WN, Ashford S, Elliott V, MacNamara A, Millar D. A clinical trial of automatic gain control in obstetric ultrasonics. Br J Radiol 1983; 56:964-8. [PMID: 6360293 DOI: 10.1259/0007-1285-56-672-964] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
|