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von Eckardstein A, Nordestgaard BG, Remaley AT, Catapano AL. High-density lipoprotein revisited: biological functions and clinical relevance. Eur Heart J 2022; 44:1394-1407. [PMID: 36337032 PMCID: PMC10119031 DOI: 10.1093/eurheartj/ehac605] [Citation(s) in RCA: 61] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/16/2022] [Accepted: 10/10/2022] [Indexed: 11/09/2022] Open
Abstract
Abstract
Previous interest in high-density lipoproteins (HDLs) focused on their possible protective role in atherosclerotic cardiovascular disease (ASCVD). Evidence from genetic studies and randomized trials, however, questioned that the inverse association of HDL-cholesterol (HDL-C) is causal. This review aims to provide an update on the role of HDL in health and disease, also beyond ASCVD. Through evolution from invertebrates, HDLs are the principal lipoproteins, while apolipoprotein B-containing lipoproteins first developed in vertebrates. HDLs transport cholesterol and other lipids between different cells like a reusable ferry, but serve many other functions including communication with cells and the inactivation of biohazards like bacterial lipopolysaccharides. These functions are exerted by entire HDL particles or distinct proteins or lipids carried by HDL rather than by its cholesterol cargo measured as HDL-C. Neither does HDL-C measurement reflect the efficiency of reverse cholesterol transport. Recent studies indicate that functional measures of HDL, notably cholesterol efflux capacity, numbers of HDL particles, or distinct HDL proteins are better predictors of ASCVD events than HDL-C. Low HDL-C levels are related observationally, but also genetically, to increased risks of infectious diseases, death during sepsis, diabetes mellitus, and chronic kidney disease. Additional, but only observational, data indicate associations of low HDL-C with various autoimmune diseases, and cancers, as well as all-cause mortality. Conversely, extremely high HDL-C levels are associated with an increased risk of age-related macular degeneration (also genetically), infectious disease, and all-cause mortality. HDL encompasses dynamic multimolecular and multifunctional lipoproteins that likely emerged during evolution to serve several physiological roles and prevent or heal pathologies beyond ASCVD. For any clinical exploitation of HDL, the indirect marker HDL-C must be replaced by direct biomarkers reflecting the causal role of HDL in the respective disease.
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Affiliation(s)
- Arnold von Eckardstein
- Institute of Clinical Chemistry, University Hospital Zurich and University of Zurich , Zurich , Switzerland
| | - Børge G Nordestgaard
- Department of Clinical Biochemistry, Copenhagen University Hospital, Herlev and Gentofte Hospital , Herlev , Denmark
- The Copenhagen General Population Study, Copenhagen University Hospital, Herlev and Gentofte Hospital , Herlev , Denmark
- Institute of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark
| | - Alan T Remaley
- Lipoprotein Metabolism Section, Translational Vascular Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health , Bethesda, MD , USA
| | - Alberico L Catapano
- Department of Pharmacological and Biomolecular Sciences, University of Milan , Milan , Italy
- IRCCS MultiMedica, Sesto S. Giovanni , Milan , Italy
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Davidson WS, Shah AS, Sexmith H, Gordon SM. The HDL Proteome Watch: Compilation of studies leads to new insights on HDL function. Biochim Biophys Acta Mol Cell Biol Lipids 2022; 1867:159072. [PMID: 34800735 PMCID: PMC8715479 DOI: 10.1016/j.bbalip.2021.159072] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/30/2021] [Accepted: 11/01/2021] [Indexed: 01/01/2023]
Abstract
PURPOSE OF REVIEW High density lipoproteins (HDL) are a heterogeneous family of particles that contain distinct complements of proteins that define their function. Thus, it is important to accurately and sensitively identify proteins associated with HDL. Here we highlight the HDL Proteome Watch Database which tracks proteomics studies from different laboratories across the world. RECENT FINDINGS In 45 published reports, almost 1000 individual proteins have been detected in preparations of HDL. Of these, 251 have been identified in at least three different laboratories. The known functions of these consensus HDL proteins go well beyond traditionally recognized roles in lipid transport with many proteins pointing to HDL functions in innate immunity, inflammation, cell adhesion, hemostasis and protease regulation, and even vitamin and metal binding. SUMMARY The HDL proteome derived across multiple studies using various methodologies provides confidence in protein identifications that can offer interesting new insights into HDL function. We also point out significant issues that will require additional study going forward.
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Affiliation(s)
- W Sean Davidson
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, OH 45237, United States of America.
| | - Amy S Shah
- Department of Pediatrics, Division of Endocrinology, Cincinnati Children's Hospital Medical Center and the University of Cincinnati, Cincinnati, OH 45229, United States of America.
| | - Hannah Sexmith
- Department of Pediatrics, Division of Endocrinology, Cincinnati Children's Hospital Medical Center and the University of Cincinnati, Cincinnati, OH 45229, United States of America.
| | - Scott M Gordon
- Saha Cardiovascular Research Center and Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, United States of America.
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Abstract
African trypanosomes are responsible for important diseases of humans and animals in sub-Saharan Africa. The best-studied species is Trypanosoma brucei, which is characterized by development in the mammalian host between morphologically slender and stumpy forms. The latter are adapted for transmission by the parasite's vector, the tsetse fly. The development of stumpy forms is driven by density-dependent quorum-sensing (QS), the molecular basis for which is now coming to light. In this review, I discuss the historical context and biological features of trypanosome QS and how it contributes to the parasite's infection dynamics within its mammalian host. Also, I discuss how QS can be lost in different trypanosome species, such as T. brucei evansi and T. brucei equiperdum, or modulated when parasites find themselves competing with others of different genotypes or of different trypanosome species in the same host. Finally, I consider the potential to exploit trypanosome QS therapeutically. Expected final online publication date for the Annual Review of Microbiology, Volume 75 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Keith R Matthews
- Institute for Immunology and Infection Research, Ashworth Laboratories, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, United Kingdom;
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de Castro Neto AL, da Silveira JF, Mortara RA. Comparative Analysis of Virulence Mechanisms of Trypanosomatids Pathogenic to Humans. Front Cell Infect Microbiol 2021; 11:669079. [PMID: 33937106 PMCID: PMC8085324 DOI: 10.3389/fcimb.2021.669079] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 03/30/2021] [Indexed: 11/23/2022] Open
Abstract
Trypanosoma brucei, Leishmania spp., and T. cruzi are flagellate protozoans of the family Trypanosomatidae and the causative agents of human African trypanosomiasis, leishmaniasis, and Chagas disease, respectively. These diseases affect humans worldwide and exert a significant impact on public health. Over the course of evolution, the parasites associated with these pathologies have developed mechanisms to circumvent the immune response system throughout the infection cycle. In cases of human infection, this function is undertaken by a group of proteins and processes that allow the parasites to propagate and survive during host invasion. In T. brucei, antigenic variation is promoted by variant surface glycoproteins and other proteins involved in evasion from the humoral immune response, which helps the parasite sustain itself in the extracellular milieu during infection. Conversely, Leishmania spp. and T. cruzi possess a more complex infection cycle, with specific intracellular stages. In addition to mechanisms for evading humoral immunity, the pathogens have also developed mechanisms for facilitating their adhesion and incorporation into host cells. In this review, the different immune evasion strategies at cellular and molecular levels developed by these human-pathogenic trypanosomatids have been discussed, with a focus on the key molecules responsible for mediating the invasion and evasion mechanisms and the effects of these molecules on virulence.
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Affiliation(s)
- Artur Leonel de Castro Neto
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - José Franco da Silveira
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Renato Arruda Mortara
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
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Davidson WS, Cooke AL, Swertfeger DK, Shah AS. The Difference Between High Density Lipoprotein Subfractions and Subspecies: an Evolving Model in Cardiovascular Disease and Diabetes. Curr Atheroscler Rep 2021; 23:23. [PMID: 33772657 DOI: 10.1007/s11883-021-00925-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/09/2021] [Indexed: 12/20/2022]
Abstract
PURPOSE OF REVIEW The term high density lipoproteins (HDL) refers to an eclectic collection of subparticles that play diverse roles in physiology. Here, we define the term "HDL subspecies" and review recent work on their molecular characterization and relation to disease, focusing on cardiovascular disease and diabetes. RECENT FINDINGS The HDL family contains over 200 proteins and nearly 200 lipids that partition into different particles in plasma. Simple subfractionation of HDL based on a particular physicochemical property has not risen to the challenge of revealing the roles of specific particles in disease. However, by targeting minor protein or lipid components, a handful of compositionally defined HDL subspecies have been described and characterized. By combining targeted particle isolation techniques with the power of large human studies, progress is being made in understanding HDL subspecies functions and implications for disease. However, much work remains before these advancements can be translated into disease mitigation strategies.
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Affiliation(s)
- W Sean Davidson
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, OH, 45237, USA.
| | | | - Debi K Swertfeger
- Department of Biomedical Informatics, Cincinnati Children's Hospital Medical Center, Cincinnati, 45229, USA
| | - Amy S Shah
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, 45229, USA
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De Simone G, Pasquadibisceglie A, Polticelli F, di Masi A, Ascenzi P. Haptoglobin and the related haptoglobin protein: the N-terminus makes the difference. J Biomol Struct Dyn 2020; 40:2244-2253. [DOI: 10.1080/07391102.2020.1837675] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
| | | | - Fabio Polticelli
- Dipartimento di Scienze, Università Roma Tre, Roma, Italy
- Istituto Nazionale di Fisica Nucleare, Roma Tre Section, Roma, Italy
| | | | - Paolo Ascenzi
- Laboratorio Interdipartimentale di Microscopia Elettronica, Università Roma Tre, Roma, Italy
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Tauheed AM, Mamman M, Ahmed A, Suleiman MM, Balogun EO. In vitro and in vivo antitrypanosomal efficacy of combination therapy of Anogeissus leiocarpus, Khaya senegalensis and potash. JOURNAL OF ETHNOPHARMACOLOGY 2020; 258:112805. [PMID: 32243988 DOI: 10.1016/j.jep.2020.112805] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 03/11/2020] [Accepted: 03/25/2020] [Indexed: 06/11/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Pastoralists in Nigeria mix barks of Anogeissus leiocarpus (AL) Khaya senegalensis (KS) and potash (Pt) to treat animal African trypanosomosis. AIM To evaluate antitrypanosomal potential of A. leiocarpus, K. senegalensis and potash for insights into the traditional claim of antitrypanosomal combination therapy (ATCT). MATERIALS AND METHODS Fifty microliter each of six different concentrations of AL, KS, Pt, AL + KS, AL + KS + Pt and diminazene aceturate (DA, positive control) was incubated with 50 μL of parasite-laden blood containing 108Trypanosoma congolense cells in a 96-well microtitre plate. Negative control wells were devoid of the extracts and drug but supplemented with phosphate-buffered saline (PBS). Efficacy of treatment was observed at 1 h interval for complete immobilisation or reduced motility of the parasites. Each incubated mixture was inoculated into mouse at the point of complete immobilisation of parasite motility or at the end of 6-h observation period for concentrations that did not immobilise the parasites completely. For in vivo assessment, thirty-five parasitaemic rats were randomly allocated into seven groups of 5 rats each. Each rat in groups I-V was treated with 500 mg/kg of AL, KS, Pt, AL + KS and AL + KS + Pt, respectively, for 7 days. Rats in groups VI and VII were treated with diminazene aceturate 3.5 mg/kg once and PBS 2 mL/kg (7 days), which served as positive and negative controls, respectively. Daily monitoring of parasitaemia through the tail vein, packed cell volume and malondialdehyde were used to assess efficacy of the treatments. RESULTS The AL + KS + Pt group significantly (p < 0.05) and dose-dependently reduced parasite motility and completely immobilized the parasites at 10, 5 and 2.5 μg/μL with an IC50 of 9.1×10-4 µg/µL. All the mice with conditions that produced complete cessation of parasite motility did not develop parasitaemia within one month of observation. The AL + KS group significantly (p < 0.05) lowered the level of parasitaemia and MDA, and significantly (p < 0.05) maintained higher PCV than PBS group. CONCLUSION The combination of A. leiocarpus and K. senegalensis showed better antitrypanosomal effects than single drug treatment and offers prospects for ATCT. Our findings support ethnopharmacological use of combined barks of A. leiocarpus and K. senegalensis by pastoralist in the treatment of animal African trypanosomosis in Nigeria.
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Affiliation(s)
- Abdullah M Tauheed
- Department of Veterinary Pharmacology and Toxicology, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, Kaduna State, Nigeria.
| | - Mohammed Mamman
- Department of Veterinary Pharmacology and Toxicology, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, Kaduna State, Nigeria
| | - Abubakar Ahmed
- Department of Pharmacognosy and Drug Development, Faculty of Pharmaceutical Sciences, Ahmadu Bello University, Zaria, Kaduna State, Nigeria
| | - Mohammed M Suleiman
- Department of Veterinary Pharmacology and Toxicology, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, Kaduna State, Nigeria; College of Agriculture and Animal Science, Mando, Ahmadu Bello University, Kaduna State, Nigeria
| | - Emmanuel O Balogun
- Department of Biochemistry, Faculty of Life Sciences, Ahmadu Bello University, Zaria, Kaduna State, Nigeria; School of Pharmaceutical Sciences, University of California San Diego, United States of America
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Divers J, Langefeld CD, Lyles DS, Ma L, Freedman BI. Protective association between JC polyoma viruria and kidney disease. Curr Opin Nephrol Hypertens 2019; 28:65-69. [PMID: 30320619 PMCID: PMC9070104 DOI: 10.1097/mnh.0000000000000464] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
PURPOSE OF REVIEW The presence of viruses in urine (urine virome) typically reflects infection in the kidneys and urinary tract. The urinary virome is associated with HIV-associated nephropathy and chronic glomerulosclerosis. There are many associations of this microbiome with human diseases that remain to be described. This manuscript reviews emerging data on relationships between kidney disease and urinary tract infection/colonization with JC polyomavirus (JCPyV). RECENT FINDINGS Approximately 30% of the adult population sheds JCPyV in the urine. Further, urinary tract infection with one polyomavirus strain appears to inhibit secondary infections. The presence of urinary JCPyV and BK polyomavirus (BKPyV) replication were measured with polymerase chain reaction in African Americans to assess relationships with apolipoprotein L1 gene (APOL1)-associated nephropathy. Urinary JCPyV was associated with paradoxically lower rates of nephropathy in those with APOL1 high-risk genotypes. Subsequent studies revealed African Americans with JCPyV viruria had lower rates of nondiabetic nephropathy independent from APOL1. SUMMARY Urinary tract JCPyV replication is common and associates with lower rates of nephropathy. This relationship is observed in diverse settings. Results support a host immune system that fails to eradicate nonnephropathic viruses and is also less likely to manifest renal parenchymal inflammation resulting in glomerulosclerosis.
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Affiliation(s)
- Jasmin Divers
- Division of Public Health Sciences, Department of Biostatistical Sciences, Section on Nephrology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Carl D. Langefeld
- Division of Public Health Sciences, Department of Biostatistical Sciences, Section on Nephrology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Douglas S. Lyles
- Department of Biochemistry, Section on Nephrology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Lijun Ma
- Department of Internal Medicine, Section on Nephrology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Barry I. Freedman
- Department of Internal Medicine, Section on Nephrology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
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Lipoproteins from vertebrate host blood plasma are involved in Trypanosoma cruzi epimastigote agglutination and participate in interaction with the vector insect, Rhodnius prolixus. Exp Parasitol 2018; 195:24-33. [DOI: 10.1016/j.exppara.2018.09.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 08/14/2018] [Accepted: 09/23/2018] [Indexed: 01/30/2023]
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Salim B, Hayashida K, Mossaad E, Nakao R, Yamagishi J, Sugimoto C. Development and validation of direct dry loop mediated isothermal amplification for diagnosis of Trypanosoma evansi. Vet Parasitol 2018; 260:53-57. [PMID: 30197015 DOI: 10.1016/j.vetpar.2018.08.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 08/20/2018] [Accepted: 08/21/2018] [Indexed: 10/28/2022]
Abstract
Non-tsetse transmitted Trypanosoma evansi infection (Surra) is one of the most important diseases of camels in north and east Africa and of buffalo and cattle in Asia. Early, accurate and feasible diagnosis is a crucial step towards the control of Surra. Dry format of loop-mediated isothermal amplification (LAMP) diagnostics for the detection of T. evansi was developed, where the detection limit was determined as to equivalent to one parasite per reaction. The assay was validated by testing blood from 48 camels clinically diagnosed to have Surra, which all tested negative microscopically and revealed 43 (89.6%) to be positive for T. evansi when tested by the dry-LAMP. Furthermore, DNA extracted from a randomly selected subset of 20 of these blood samples were then subjected to RoTat1.2-PCR (TaKara Ex Taq), with 14 matching results, with six that were positive by dry-LAMP and negative by PCR. The kappa value of dry-LAMP applied to direct blood was 0.4211, indicating moderate agreement to RoTat 1.2-PCR. In addition, 103 genomic DNA extracted from camels' blood were tested by both dry-LAMP and RoTat1.2-PCR revealed 67 matching results and 31 positive by dry-LAMP and negative by PCR and a further five positives by PCR and negative by dry-LAMP. This novel dry-LAMP method is more sensitive than conventional PCR, direct (without DNA extraction step), is user friendly and does not require cold chain or highly trained personnel.
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Affiliation(s)
- Bashir Salim
- Department of Parasitology, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan; Laboratory of Parasitology, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
| | - Kyoko Hayashida
- Department of Collaboration and Education, Research Center for Zoonosis Control, Hokkaido University, Sapporo, 001-0020, Japan.
| | - Ehab Mossaad
- Department of Pathology, Parasitology and Microbiology, College of Veterinary Medicine, Sudan University of Science and Technology, P.O. Box 204, Khartoum, Sudan.
| | - Ryo Nakao
- Laboratory of Parasitology, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
| | - Junya Yamagishi
- Department of Collaboration and Education, Research Center for Zoonosis Control, Hokkaido University, Sapporo, 001-0020, Japan.
| | - Chihiro Sugimoto
- Department of Collaboration and Education, Research Center for Zoonosis Control, Hokkaido University, Sapporo, 001-0020, Japan.
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Manivel G, Meyyazhagan A, Durairaj D R, Piramanayagam S. Genome-wide analysis of Excretory/Secretory proteins in Trypanosoma brucei brucei: Insights into functional characteristics and identification of potential targets by immunoinformatics approach. Genomics 2018; 111:1124-1133. [PMID: 30006035 DOI: 10.1016/j.ygeno.2018.07.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 06/28/2018] [Accepted: 07/08/2018] [Indexed: 11/28/2022]
Abstract
Trypanosoma brucei brucei (T.b.brucei) is an extra-cellular parasite that causes Animal African Trypanosomiasis (AAT) disease in animals. Till day, this disease is more difficult to treat and control due to lack of efficient vaccines and early diagnosis of the parasite infection. T.b.brucei Excretory/Secretory (ES) proteins were involved in pathogenesis and key for understanding the host-parasite interactions. Functions of T.b.brucei's ES proteins were poorly investigated and experimental identification is expensive and time-consuming. Bioinformatics approaches are cost-effective by facilitating the experimental analysis of potential drug targets for parasitic diseases. Here we applied several bioinformatics tools to predict and functionalize the annotation of 1104 ES proteins and immunoinformatics approaches carried out to predict and evaluate the epitopes in T.b.brucei. Secretory information, functional annotations and potential epitopes of each ES proteins were available at http://tbb.insilico.in. This study provides functional information of T.b.brucei for experimental studies to identify potential targets for diagnosis and therapeutics development.
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Affiliation(s)
- Gowdham Manivel
- Department of Bioinformatics, Bharathiar University, Coimbatore, India.
| | - Arun Meyyazhagan
- Cytogenetics Department, EuroEspes Biomedical Research Center, Institute of Medical Science and Genomic Medicine, 15165 Bergondo, Corunna, Spain
| | - Ruban Durairaj D
- Department of Bioinformatics, Bharathiar University, Coimbatore, India
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Reidy KJ, Hjorten R, Parekh RS. Genetic risk of APOL1 and kidney disease in children and young adults of African ancestry. Curr Opin Pediatr 2018; 30:252-259. [PMID: 29406442 PMCID: PMC6002812 DOI: 10.1097/mop.0000000000000603] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE OF REVIEW Understanding the genetic risk of APOL1 in children and young adults is important given the lifetime risk of hypertension and kidney disease among children of African descent. We review recent epidemiologic and biologic findings on the effects of APOL1 and kidney disease. RECENT FINDINGS APOL1 in children and young adults is associated with hypertension, albuminuria and more rapid decline in kidney function and progression to end-stage kidney disease, especially among those with glomerular causes of kidney disease, and those affected by sickle cell disease or HIV. There are conflicting data on the APOL1 association with cardiovascular disease in children and young adults. APOL1 functions as part of the innate immune system. Podocyte expression of APOL1 likely contributes to the development of kidney disease. In cell culture and model organisms, APOL1 expression disrupts autophagic and ion flux, leads to defects in mitochondrial respiration and induces cell death. SUMMARY APOL1 explains almost 70% of the excess risk of kidney disease in those of African descent, and is common in children with glomerular disease. An evolving understanding of the pathogenesis of APOL1-mediated kidney damage may aid in personalized medicine approaches to APOL1 attributable kidney disease.
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Affiliation(s)
- Kimberly J Reidy
- Children’s Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Rebecca Hjorten
- Children’s Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Nephrology and Hypertension, Cincinnati Children's Hospital Medical Center
| | - Rulan S. Parekh
- Departments of Pediatrics and Medicine, Hospital for Sick Children, University Health Network and University of Toronto, Toronto, Canada
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Higgins MK, Lane-Serff H, MacGregor P, Carrington M. A Receptor's Tale: An Eon in the Life of a Trypanosome Receptor. PLoS Pathog 2017; 13:e1006055. [PMID: 28125726 PMCID: PMC5268388 DOI: 10.1371/journal.ppat.1006055] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
African trypanosomes have complex life cycles comprising at least ten developmental forms, variously adapted to different niches in their tsetse fly vector and their mammalian hosts. Unlike many other protozoan pathogens, they are always extracellular and have evolved intricate surface coats that allow them to obtain nutrients while also protecting them from the immune defenses of either insects or mammals. The acquisition of macromolecular nutrients requires receptors that function within the context of these surface coats. The best understood of these is the haptoglobin-hemoglobin receptor (HpHbR) of Trypanosoma brucei, which is used by the mammalian bloodstream form of the parasite, allowing heme acquisition. However, in some primates it also provides an uptake route for trypanolytic factor-1, a mediator of innate immunity against trypanosome infection. Recent studies have shown that during the evolution of African trypanosome species the receptor has diversified in function from a hemoglobin receptor predominantly expressed in the tsetse fly to a haptoglobin-hemoglobin receptor predominantly expressed in the mammalian bloodstream. Structural and functional studies of homologous receptors from different trypanosome species have allowed us to propose an evolutionary history for how one receptor has adapted to different roles in different trypanosome species. They also highlight the challenges that a receptor faces in operating on the complex trypanosome surface and show how these challenges can be met.
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Affiliation(s)
- Matthew K. Higgins
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Harriet Lane-Serff
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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de Silva Rodrigues JH, Stein J, Strauss M, Rivarola HW, Ueda-Nakamura T, Nakamura CV, Duszenko M. Clomipramine kills Trypanosoma brucei by apoptosis. Int J Med Microbiol 2016; 306:196-205. [DOI: 10.1016/j.ijmm.2016.03.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 03/07/2016] [Accepted: 03/28/2016] [Indexed: 12/31/2022] Open
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A Replicative In Vitro Assay for Drug Discovery against Leishmania donovani. Antimicrob Agents Chemother 2016; 60:3524-32. [PMID: 27021313 DOI: 10.1128/aac.01781-15] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 03/18/2016] [Indexed: 11/20/2022] Open
Abstract
The protozoan parasite Leishmania donovani is the causative agent of visceral leishmaniasis, a disease potentially fatal if not treated. Current available treatments have major limitations, and new and safer drugs are urgently needed. In recent years, advances in high-throughput screening technologies have enabled the screening of millions of compounds to identify new antileishmanial agents. However, most of the compounds identified in vitro did not translate their activities when tested in in vivo models, highlighting the need to develop more predictive in vitro assays. In the present work, we describe the development of a robust replicative, high-content, in vitro intracellular L. donovani assay. Horse serum was included in the assay media to replace standard fetal bovine serum, to completely eliminate the extracellular parasites derived from the infection process. A novel phenotypic in vitro infection model has been developed, complemented with the identification of the proliferation of intracellular amastigotes measured by EdU incorporation. In vitro and in vivo results for miltefosine, amphotericin B, and the selected compound 1 have been included to validate the assay.
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Kuriakose SM, Singh R, Uzonna JE. Host Intracellular Signaling Events and Pro-inflammatory Cytokine Production in African Trypanosomiasis. Front Immunol 2016; 7:181. [PMID: 27242788 PMCID: PMC4872169 DOI: 10.3389/fimmu.2016.00181] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 04/27/2016] [Indexed: 12/21/2022] Open
Abstract
Pathogens, such as bacteria, viruses, and parasites, possess specific molecules or proteins that are recognized by several host innate immune receptors, leading to the activation of several intracellular signaling molecules and pathways. The magnitude and quality of these events significantly affect the outcome of infection. African trypanosomes, including Trypanosoma congolense, are capable of manipulating the host immune response, including the activity of macrophages, which are the key immune cells that contribute to the immunopathogenesis of African trypanosomiasis. Although it is known that immune hyperactivation and excessive pro-inflammatory cytokine production are the hallmarks of African trypanosomiasis, the mechanisms through which these events are triggered are poorly defined. However, it is known that macrophages may play a significant role in these processes, because phagocytosis of trypanosomes by macrophages initiates intracellular signal transduction cascades that lead to the release of pro-inflammatory cytokines and alteration in cell function. This review highlights recent progress in our understanding of the innate immune receptors, signaling pathways, and transcription factors involved in T. congolense-induced pro-inflammatory cytokine production in macrophages. It will reveal the existence of complex signaling events through which the parasite modulates the host immune response, thus identifying novel targets that could aid in designing strategies to effectively control the disease.
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Affiliation(s)
- Shiby M Kuriakose
- Department of Immunology, Faculty of Health Sciences, University of Manitoba , Winnipeg, MB , Canada
| | - Rani Singh
- Department of Immunology, Faculty of Health Sciences, University of Manitoba , Winnipeg, MB , Canada
| | - Jude E Uzonna
- Department of Immunology, Faculty of Health Sciences, University of Manitoba , Winnipeg, MB , Canada
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Dummer PD, Limou S, Rosenberg AZ, Heymann J, Nelson G, Winkler CA, Kopp JB. APOL1 Kidney Disease Risk Variants: An Evolving Landscape. Semin Nephrol 2016. [PMID: 26215860 DOI: 10.1016/j.semnephrol.2015.04.008] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Apolipoprotein L1 (APOL1) genetic variants account for much of the excess risk of chronic and end-stage kidney disease, which results in a significant global health disparity for persons of African ancestry. We estimate the lifetime risk of kidney disease in APOL1 dual-risk allele individuals to be at least 15%. Experimental evidence suggests a direct role of APOL1 in pore formation, cellular injury, and programmed cell death in renal injury. The APOL1 BH3 motif, often associated with cell death, is unlikely to play a role in APOL1-induced cytotoxicity because it is not conserved within the APOL family and is dispensable for cell death in vitro. We discuss two models for APOL1 trypanolytic activity: one involving lysosome permeabilization and another involving colloid-osmotic swelling of the cell body, as well as their relevance to human pathophysiology. Experimental evidence from human cell culture models suggests that both mechanisms may be operative. A systems biology approach whereby APOL1-associated perturbations in gene and protein expression in affected individuals are correlated with molecular pathways may be productive to elucidate APOL1 function in vivo.
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Affiliation(s)
- Patrick D Dummer
- Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD
| | - Sophie Limou
- Molecular Epidemiology Genetics Section, Center for Cancer Research, National Cancer Institute, Frederick MD
| | - Avi Z Rosenberg
- Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD; Department of Pathology Johns Hopkins University, Baltimore, MD
| | - Jurgen Heymann
- Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD
| | - George Nelson
- Molecular Epidemiology Genetics Section, Center for Cancer Research, National Cancer Institute, Frederick MD
| | - Cheryl A Winkler
- Molecular Epidemiology Genetics Section, Center for Cancer Research, National Cancer Institute, Frederick MD
| | - Jeffrey B Kopp
- Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD.
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Jirků M, Votýpka J, Petrželková KJ, Jirků-Pomajbíková K, Kriegová E, Vodička R, Lankester F, Leendertz SAJ, Wittig RM, Boesch C, Modrý D, Ayala FJ, Leendertz FH, Lukeš J. Wild chimpanzees are infected by Trypanosoma brucei. INTERNATIONAL JOURNAL FOR PARASITOLOGY-PARASITES AND WILDLIFE 2015; 4:277-82. [PMID: 26110113 PMCID: PMC4477118 DOI: 10.1016/j.ijppaw.2015.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 04/23/2015] [Accepted: 05/11/2015] [Indexed: 12/23/2022]
Abstract
Although wild chimpanzees and other African great apes live in regions endemic for African sleeping sickness, very little is known about their trypanosome infections, mainly due to major difficulties in obtaining their blood samples. In present work, we established a diagnostic ITS1-based PCR assay that allows detection of the DNA of all four Trypanosoma brucei subspecies (Trypanosoma bruceibrucei, Trypanosoma bruceirhodesiense, Trypanosoma bruceigambiense, and Trypanosoma bruceievansi) in feces of experimentally infected mice. Next, using this assay we revealed the presence of trypanosomes in the fecal samples of wild chimpanzees and this finding was further supported by results obtained using a set of primate tissue samples. Phylogenetic analysis of the ITS1 region showed that the majority of obtained sequences fell into the robust T. brucei group, providing strong evidence that these infections were caused by T. b. rhodesiense and/or T. b. gambiense. The optimized technique of trypanosome detection in feces will improve our knowledge about the epidemiology of trypanosomes in primates and possibly also other endangered mammals, from which blood and tissue samples cannot be obtained. Finally, we demonstrated that the mandrill serum was able to efficiently lyse T. b. brucei and T. b. rhodesiense, and to some extent T. b. gambiense, while the chimpanzee serum failed to lyse any of these subspecies. ITS1-based PCR allows the detection of the Trypanosoma brucei in feces of non-human primates. Wild chimpanzees are frequently infected with the T. brucei subspecies. Mandrill serum efficiently lyses also Trypanosoma bruceigambiense.
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Affiliation(s)
- Milan Jirků
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice (Budweiss), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweiss), Czech Republic
| | - Jan Votýpka
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice (Budweiss), Czech Republic
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Klára J. Petrželková
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice (Budweiss), Czech Republic
- Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, Czech Republic
- Liberec Zoo, Liberec, Czech Republic
- Department of Pathology and Parasitology, University of Veterinary and Pharmaceutical Sciences Brno, Czech Republic
| | - Kateřina Jirků-Pomajbíková
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice (Budweiss), Czech Republic
| | - Eva Kriegová
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice (Budweiss), Czech Republic
| | | | - Felix Lankester
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, USA
| | - Siv Aina J. Leendertz
- Research Group for Epidemiology of Highly Pathogenic Microorganisms, Koch Institute, Berlin, Germany
| | - Roman M. Wittig
- Department of Primatology, Max-Planck-Institute for Evolutionary Anthropology, Leipzig, Germany
- Centre Suisse des Recherches Scientifiques, Abidjan, Cote d'Ivoire
| | | | - David Modrý
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice (Budweiss), Czech Republic
- Department of Pathology and Parasitology, University of Veterinary and Pharmaceutical Sciences Brno, Czech Republic
- Central European Institute of Technology, Brno, Czech Republic
| | - Francisco J. Ayala
- Department of Ecology and Evolutionary Biology, University of California, Irvine, USA
| | - Fabian H. Leendertz
- Department of Primatology, Max-Planck-Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice (Budweiss), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweiss), Czech Republic
- Canadian Institute for Advanced Research, Toronto, Canada
- Corresponding author. Institute of Parasitology, Branišovská 31, 37005, České Budějovice, Czech Republic.
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Matthews KR. 25 years of African trypanosome research: From description to molecular dissection and new drug discovery. Mol Biochem Parasitol 2015; 200:30-40. [PMID: 25736427 PMCID: PMC4509711 DOI: 10.1016/j.molbiopara.2015.01.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 01/09/2015] [Accepted: 01/13/2015] [Indexed: 01/27/2023]
Abstract
The Molecular Parasitology conference was first held at the Marine Biological laboratory, Woods Hole, USA 25 years ago. Since that first meeting, the conference has evolved and expanded but has remained the showcase for the latest research developments in molecular parasitology. In this perspective, I reflect on the scientific discoveries focussed on African trypanosomes (Trypanosoma brucei spp.) that have occurred since the inaugural MPM meeting and discuss the current and future status of research on these parasites.
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Affiliation(s)
- Keith R Matthews
- Centre for Immunity, Infection and Evolution, Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JT, UK.
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Abstract
During infection significant alterations in lipid metabolism and lipoprotein composition occur. Triglyceride and VLDL cholesterol levels increase, while reduced HDL cholesterol (HDL-C) and LDL cholesterol (LDL-C) levels are observed. More importantly, endotoxemia modulates HDL composition and size: phospholipids are reduced as well as apolipoprotein (apo) A-I, while serum amyloid A (SAA) and secretory phospholipase A2 (sPLA2) dramatically increase, and, although the total HDL particle number does not change, a significant decrease in the number of small- and medium-size particles is observed. Low HDL-C levels inversely correlate with the severity of septic disease and associate with an exaggerated systemic inflammatory response. HDL, as well as other plasma lipoproteins, can bind and neutralize Gram-negative bacterial lipopolysaccharide (LPS) and Gram-positive bacterial lipoteichoic acid (LTA), thus favoring the clearance of these products. HDLs are emerging also as a relevant player during parasitic infections, and a specific component of HDL, namely, apoL-1, confers innate immunity against trypanosome by favoring lysosomal swelling which kills the parasite. During virus infections, proteins associated with the modulation of cholesterol bioavailability in the lipid rafts such as ABCA1 and SR-BI have been shown to favor virus entry into the cells. Pharmacological studies support the benefit of recombinant HDL or apoA-I mimetics during bacterial infection, while apoL-1-nanobody complexes were tested for trypanosome infection. Finally, SR-BI antagonism represents a novel and forefront approach interfering with hepatitis C virus entry which is currently tested in clinical studies. From the coming years, we have to expect new and compelling observations further linking HDL to innate immunity and infections.
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Mogk S, Meiwes A, Shtopel S, Schraermeyer U, Lazarus M, Kubata B, Wolburg H, Duszenko M. Cyclical appearance of African trypanosomes in the cerebrospinal fluid: new insights in how trypanosomes enter the CNS. PLoS One 2014; 9:e91372. [PMID: 24618708 PMCID: PMC3950183 DOI: 10.1371/journal.pone.0091372] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 02/09/2014] [Indexed: 11/25/2022] Open
Abstract
It is textbook knowledge that human infective forms of Trypanosoma brucei, the causative agent of sleeping sickness, enter the brain across the blood-brain barrier after an initial phase of weeks (rhodesiense) or months (gambiense) in blood. Based on our results using an animal model, both statements seem questionable. As we and others have shown, the first infection relevant crossing of the blood brain border occurs via the choroid plexus, i.e. via the blood-CSF barrier. In addition, counting trypanosomes in blood-free CSF obtained by an atlanto-occipital access revealed a cyclical infection in CSF that was directly correlated to the trypanosome density in blood infection. We also obtained conclusive evidence of organ infiltration, since parasites were detected in tissues outside the blood vessels in heart, spleen, liver, eye, testis, epididymis, and especially between the cell layers of the pia mater including the Virchow-Robin space. Interestingly, in all organs except pia mater, heart and testis, trypanosomes showed either a more or less degraded appearance of cell integrity by loss of the surface coat (VSG), loss of the microtubular cytoskeleton and loss of the intracellular content, or where taken up by phagocytes and degraded intracellularly within lysosomes. This is also true for trypanosomes placed intrathecally into the brain parenchyma using a stereotactic device. We propose a different model of brain infection that is in accordance with our observations and with well-established facts about the development of sleeping sickness.
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Affiliation(s)
- Stefan Mogk
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Andreas Meiwes
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Swetlana Shtopel
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | | | - Michael Lazarus
- International Institute for Integrative Sleep Medicine, University of Tsukuba, Tsukuba, Japan
| | | | - Hartwig Wolburg
- Institute of Pathology and Neuropathology, University of Tübingen, Tübingen, Germany
| | - Michael Duszenko
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
- Faculty of Medicine and Life Sciences, Tongji University, Shanghai, P. R. China
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23
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Ko WY, Rajan P, Gomez F, Scheinfeldt L, An P, Winkler CA, Froment A, Nyambo T, Omar S, Wambebe C, Ranciaro A, Hirbo J, Tishkoff S. Identifying Darwinian selection acting on different human APOL1 variants among diverse African populations. Am J Hum Genet 2013; 93:54-66. [PMID: 23768513 PMCID: PMC3710747 DOI: 10.1016/j.ajhg.2013.05.014] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 04/10/2013] [Accepted: 05/20/2013] [Indexed: 12/24/2022] Open
Abstract
Disease susceptibility can arise as a consequence of adaptation to infectious disease. Recent findings have suggested that higher rates of chronic kidney disease (CKD) in individuals with recent African ancestry might be attributed to two risk alleles (G1 and G2) at the serum-resistance-associated (SRA)-interacting-domain-encoding region of APOL1. These two alleles appear to have arisen adaptively, possibly as a result of their protective effects against human African trypanosomiasis (HAT), or African sleeping sickness. In order to explore the distribution of potential functional variation at APOL1, we studied nucleotide variation in 187 individuals across ten geographically and genetically diverse African ethnic groups with exposure to two Trypanosoma brucei subspecies that cause HAT. We observed unusually high levels of nonsynonymous polymorphism in the regions encoding the functional domains that are required for lysing parasites. Whereas allele frequencies of G2 were similar across all populations (3%-8%), the G1 allele was only common in the Yoruba (39%). Additionally, we identified a haplotype (termed G3) that contains a nonsynonymous change at the membrane-addressing-domain-encoding region of APOL1 and is present in all populations except for the Yoruba. Analyses of long-range patterns of linkage disequilibrium indicate evidence of recent selection acting on the G3 haplotype in Fulani from Cameroon. Our results indicate that the G1 and G2 variants in APOL1 are geographically restricted and that there might be other functional variants that could play a role in HAT resistance and CKD risk in African populations.
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MESH Headings
- Adaptation, Biological
- Africa
- Alleles
- Apolipoprotein L1
- Apolipoproteins/genetics
- Black People/genetics
- Disease Resistance/genetics
- Evolution, Molecular
- Exons
- Gene Frequency
- Genetic Predisposition to Disease
- Genetics, Population/methods
- Haplotypes
- Humans
- Linkage Disequilibrium
- Lipoproteins, HDL/genetics
- Molecular Sequence Data
- Polymorphism, Single Nucleotide
- Renal Insufficiency, Chronic/ethnology
- Renal Insufficiency, Chronic/genetics
- Risk Factors
- Selection, Genetic
- Trypanosomiasis, African/ethnology
- Trypanosomiasis, African/genetics
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Affiliation(s)
- Wen-Ya Ko
- Department of Genetics, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, 4485-661 Vairão, Portugal
| | - Prianka Rajan
- Department of Genetics, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Felicia Gomez
- Department of Genetics, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Anthropology, Center for the Advanced Study of Hominid Paleobiology, The George Washington University, Washington, DC 20052, USA
| | - Laura Scheinfeldt
- Department of Genetics, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ping An
- Basic Research Laboratory, Center for Cancer Research, National Cancer Institute, Frederick National Laboratory, Science Applications International Corporation-Frederick, Frederick, MD 21702, USA
| | - Cheryl A. Winkler
- Basic Research Laboratory, Center for Cancer Research, National Cancer Institute, Frederick National Laboratory, Science Applications International Corporation-Frederick, Frederick, MD 21702, USA
| | - Alain Froment
- Unité Mixte de Recherche 208, Muséum National d’Histoire Naturelle, Institut de Recherche pour le Développement, Musée de l’Homme, 75116 Paris, France
| | - Thomas B. Nyambo
- Department of Biochemistry, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Sabah A. Omar
- Kenya Medical Research Institute, Center for Biotechnology Research and Development, 54840-00200 Nairobi, Kenya
| | - Charles Wambebe
- International Biomedical Research in Africa, Kampala, Uganda
| | - Alessia Ranciaro
- Department of Genetics, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jibril B. Hirbo
- Department of Genetics, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sarah A. Tishkoff
- Department of Genetics, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
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APOL1 null alleles from a rural village in India do not correlate with glomerulosclerosis. PLoS One 2012; 7:e51546. [PMID: 23300552 PMCID: PMC3530541 DOI: 10.1371/journal.pone.0051546] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Accepted: 11/02/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Among African-Americans, genome wide association revealed a strong correlation between the G1 and G2 alleles of APOL1 (apolipoproteinL1, also called trypanolytic factor) and kidney diseases including focal and segmental glomerulosclerosis, HIV-associated nephropathy and hypertensive nephrosclerosis. In the prevailing hypothesis, heterozygous APOL1 G1 and G2 alleles increase resistance against Trypanosoma that cause African sleeping sickness, resulting in positive selection of these alleles, but when homozygous the G1 and G2 alleles predispose to glomerulosclerosis. While efforts are underway to screen patients for G1 and G2 alleles and to better understand "APOL1 glomerulopathy," no data prove that these APOL1 sequence variants cause glomerulosclerosis. G1 and G2 correlate best with glomerulosclerosis as recessive alleles, which suggests a loss of function mutation for which proof of causality is commonly tested with homozygous null alleles. This test cannot be performed in rodents as the APOL gene cluster evolved only in primates. However, there is a homozygous APOL1 null human being who lives in a village in rural India. This individual and his family offer a unique opportunity to test causality between APOL1 null alleles and glomerulosclerosis. METHODS AND FINDINGS We obtained clinical data, blood and urine from this APOL1 null patient and 50 related villagers. Based on measurements of blood pressure, BUN, creatinine, albuminuria, genotyping and immunoblotting, this APOL1 null individual does not have glomerulosclerosis, nor do his relatives who carry APOL1 null alleles. CONCLUSIONS This small study cannot provide definitive conclusions but the absence of glomerulosclerosis in this unique population is consistent with the possibility that African-American glomerulosclerosis is caused, not by loss of APOL1 function, but by other mechanisms including a subtle gain of function or by the "genetic hitchhiking" of deleterious mutations in a gene linked to APOL1 G1 and G2.
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Imrie HJ, Fowkes FJI, Migot-Nabias F, Luty AJF, Deloron P, Hajduk SL, Day KP. Individual variation in levels of haptoglobin-related protein in children from Gabon. PLoS One 2012. [PMID: 23185445 PMCID: PMC3502254 DOI: 10.1371/journal.pone.0049816] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Background Haptoglobin related protein (Hpr) is a key component of trypanosome lytic factors (TLF), a subset of high-density lipoproteins (HDL) that form the first line of human defence against African trypanosomes. Hpr, like haptoglobin (Hp) can bind to hemoglobin (Hb) and it is the Hpr-Hb complexes which bind to these parasites allowing uptake of TLF. This unique form of innate immunity is primate-specific. To date, there have been no population studies of plasma levels of Hpr, particularly in relation to hemolysis and a high prevalence of ahaptoglobinemia as found in malaria endemic areas. Methods and Principal Findings We developed a specific enzyme-linked immunosorbent assay to measure levels of plasma Hpr in Gabonese children sampled during a period of seasonal malaria transmission when acute phase responses (APR), malaria infection and associated hemolysis were prevalent. Median Hpr concentration was 0.28 mg/ml (range 0.03–1.1). This was 5-fold higher than that found in Caucasian children (0.049 mg/ml, range 0.002–0.26) with no evidence of an APR. A general linear model was used to investigate associations between Hpr levels, host polymorphisms, parasitological factors and the acute phase proteins, Hp, C-reactive protein (CRP) and albumin. Levels of Hpr were associated with Hp genotype, decreased with age and were higher in females. Hpr concentration was strongly correlated with that of Hp, but not CRP. Conclusions/Significance Individual variation in Hpr levels was related to Hp level, Hp genotype, demographics, malaria status and the APR. The strong correlations between plasma levels of Hp and Hpr suggest that they are regulated by similar mechanisms. These population-based observations indicate that a more dynamic view of the relative roles of Hpr and Hpr-Hb complexes needs to be considered in understanding innate immunity to African trypanosomes and possibly other pathogens including the newly discovered Plasmodium spp of humans and primates.
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Affiliation(s)
- Heather J. Imrie
- Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, Oxford, United Kingdom
| | - Freya J. I. Fowkes
- Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, Oxford, United Kingdom
- Department of Microbiology, Division of Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Florence Migot-Nabias
- Institut de Recherche pour le Développement, UMR 216 Mère et Enfant Face aux Infections Tropicales, Paris, France
- Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité, France
| | - Adrian J. F. Luty
- Institut de Recherche pour le Développement, UMR 216 Mère et Enfant Face aux Infections Tropicales, Paris, France
- Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité, France
| | - Philippe Deloron
- Institut de Recherche pour le Développement, UMR 216 Mère et Enfant Face aux Infections Tropicales, Paris, France
- Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité, France
| | - Stephen L. Hajduk
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Karen P. Day
- Department of Microbiology, Division of Parasitology, New York University School of Medicine, New York, New York, United States of America
- * E-mail:
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Abstract
PURPOSE OF REVIEW HDL cholesterol concentration is inversely correlated with cardiovascular disease and has a wide range of functions involved in many systems. The purpose of this review is to summarize HDL functionality, its relevance to atherosclerosis and factors affecting HDL functions. RECENT FINDINGS The contribution of HDL to reverse cholesterol transport may not be as great as first envisaged. However, it still plays an important role in cholesterol efflux from peripheral tissues. The capacity of HDL to promote cellular cholesterol efflux in an ex-vivo model has been reported to correlate more closely with carotid intima-media thickness than HDL cholesterol concentration. Recently, a variety of other functions of HDL have been described including antimicrobial, antioxidant, antiglycation, anti-inflammatory, nitric oxide--inducing, antithrombotic and antiatherogenic activity and immune modulation as well as a potential role in glucose homeostasis, diabetes pathophysiology and complications. SUMMARY HDL has a wide range of functions some of which are independent of its cholesterol content. Its cargo of apolipoproteins, various proteins and phospholipids contributes most to its various functions. These functions are affected by a number of genetic, physiological and pathological factors.
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Affiliation(s)
- Handrean Soran
- University Department of Medicine, Central Manchester and Manchester Children University Hospital NHS Foundation Trust, School of Biomedicine, University of Manchester, Manchester, UK
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27
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Symula RE, Beadell JS, Sistrom M, Agbebakun K, Balmer O, Gibson W, Aksoy S, Caccone A. Trypanosoma brucei gambiense group 1 is distinguished by a unique amino acid substitution in the HpHb receptor implicated in human serum resistance. PLoS Negl Trop Dis 2012; 6:e1728. [PMID: 22802982 PMCID: PMC3393672 DOI: 10.1371/journal.pntd.0001728] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2012] [Accepted: 05/22/2012] [Indexed: 11/18/2022] Open
Abstract
Trypanosoma brucei rhodesiense (Tbr) and T. b. gambiense (Tbg), causative agents of Human African Trypanosomiasis (sleeping sickness) in Africa, have evolved alternative mechanisms of resisting the activity of trypanosome lytic factors (TLFs), components of innate immunity in human serum that protect against infection by other African trypanosomes. In Tbr, lytic activity is suppressed by the Tbr-specific serum-resistance associated (SRA) protein. The mechanism in Tbg is less well understood but has been hypothesized to involve altered activity and expression of haptoglobin haemoglobin receptor (HpHbR). HpHbR has been shown to facilitate internalization of TLF-1 in T.b. brucei (Tbb), a member of the T. brucei species complex that is susceptible to human serum. By evaluating the genetic variability of HpHbR in a comprehensive geographical and taxonomic context, we show that a single substitution that replaces leucine with serine at position 210 is conserved in the most widespread form of Tbg (Tbg group 1) and not found in related taxa, which are either human serum susceptible (Tbb) or known to resist lysis via an alternative mechanism (Tbr and Tbg group 2). We hypothesize that this single substitution contributes to reduced uptake of TLF and thus may play a key role in conferring serum resistance to Tbg group 1. In contrast, similarity in HpHbR sequence among isolates of Tbg group 2 and Tbb/Tbr provides further evidence that human serum resistance in Tbg group 2 is likely independent of HpHbR function.
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Affiliation(s)
- Rebecca E Symula
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America.
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Loker ES. Macroevolutionary Immunology: A Role for Immunity in the Diversification of Animal life. Front Immunol 2012; 3:25. [PMID: 22566909 PMCID: PMC3342036 DOI: 10.3389/fimmu.2012.00025] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 02/08/2012] [Indexed: 11/13/2022] Open
Abstract
An emerging picture of the nature of immune systems across animal phyla reveals both conservatism of some features and the appearance among and within phyla of novel, lineage-specific defense solutions. The latter collectively represent a major and underappreciated form of animal diversity. Factors influencing this macroevolutionary (above the species level) pattern of novelty are considered and include adoption of different life styles, life histories, and body plans; a general advantage of being distinctive with respect to immune defenses; and the responses required to cope with parasites, many of which afflict hosts in a lineage-specific manner. This large-scale pattern of novelty implies that immunological phenomena can affect microevolutionary processes (at the population level within species) that can eventually lead to macroevolutionary events such as speciation, radiations, or extinctions. Immunologically based phenomena play a role in favoring intraspecific diversification, specialization and host specificity of parasites, and mechanisms are discussed whereby this could lead to parasite speciation. Host switching - the acquisition of new host species by parasites - is a major mechanism that drives parasite diversity and is frequently involved in disease emergence. It is also one that can be favored by reductions in immune competence of new hosts. Mechanisms involving immune phenomena favoring intraspecific diversification and speciation of host species are also discussed. A macroevolutionary perspective on immunology is invaluable in today's world, including the need to study a broader range of species with distinctive immune systems. Many of these species are faced with extinction, another macroevolutionary process influenced by immune phenomena.
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Affiliation(s)
- Eric S. Loker
- Center for Evolutionary and Theoretical Immunology, Department of Biology, Division of Parasitology, Museum of Southwestern Biology, University of New MexicoAlbuquerque, NM, USA
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Hu CAA, Klopfer EI, Ray PE. Human apolipoprotein L1 (ApoL1) in cancer and chronic kidney disease. FEBS Lett 2012; 586:947-55. [PMID: 22569246 DOI: 10.1016/j.febslet.2012.03.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 02/28/2012] [Accepted: 03/01/2012] [Indexed: 02/09/2023]
Abstract
Human apolipoprotein L1 (ApoL1) possesses both extra- and intra-cellular functions crucial in host defense and cellular homeostatic mechanisms. Alterations in ApoL1 function due to genetic, environmental, and lifestyle factors have been associated with African sleeping sickness, atherosclerosis, lipid disorders, obesity, schizophrenia, cancer, and chronic kidney disease (CKD). Importantly, two alleles of APOL1 carrying three coding-sequence variants have been linked to CKD, particularly in Sub-Saharan Africans and African Americans. Intracellularly, elevated ApoL1 can induce autophagy and autophagy-associated cell death, which may be critical in the maintenance of cellular homeostasis in the kidney. Similarly, ApoL1 may protect kidney cells against renal cell carcinoma (RCC). We summarize the role of ApoL1 in RCC and CKD, highlighting the critical function of ApoL1 in autophagy.
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Affiliation(s)
- Chien-An A Hu
- Department of Biochemistry and Molecular Biology, University of New Mexico, Health Sciences Center, Albuquerque, NM 87131-0001, USA.
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Teixeira SM, de Paiva RMC, Kangussu-Marcolino MM, Darocha WD. Trypanosomatid comparative genomics: Contributions to the study of parasite biology and different parasitic diseases. Genet Mol Biol 2012; 35:1-17. [PMID: 22481868 PMCID: PMC3313497 DOI: 10.1590/s1415-47572012005000008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 10/18/2011] [Indexed: 01/23/2023] Open
Abstract
In 2005, draft sequences of the genomes of Trypanosoma brucei, Trypanosoma cruzi and Leishmania major, also known as the Tri-Tryp genomes, were published. These protozoan parasites are the causative agents of three distinct insect-borne diseases, namely sleeping sickness, Chagas disease and leishmaniasis, all with a worldwide distribution. Despite the large estimated evolutionary distance among them, a conserved core of ~6,200 trypanosomatid genes was found among the Tri-Tryp genomes. Extensive analysis of these genomic sequences has greatly increased our understanding of the biology of these parasites and their host-parasite interactions. In this article, we review the recent advances in the comparative genomics of these three species. This analysis also includes data on additional sequences derived from other trypanosmatid species, as well as recent data on gene expression and functional genomics. In addition to facilitating the identification of key parasite molecules that may provide a better understanding of these complex diseases, genome studies offer a rich source of new information that can be used to define potential new drug targets and vaccine candidates for controlling these parasitic infections.
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Affiliation(s)
- Santuza M Teixeira
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
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Contribution of Innate Immune Responses towards Resistance to African Trypanosome Infections. Scand J Immunol 2011; 75:5-15. [DOI: 10.1111/j.1365-3083.2011.02619.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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An expanded family of proteins with BPI/LBP/PLUNC-like domains in trypanosome parasites: an association with pathogenicity? Biochem Soc Trans 2011; 39:966-70. [PMID: 21787331 DOI: 10.1042/bst0390966] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Trypanosomatids are protozoan parasites that cause human and animal disease. Trypanosoma brucei telomeric ESs (expression sites) contain genes that are critical for parasite survival in the bloodstream, including the VSG (variant surface glycoprotein) genes, used for antigenic variation, and the SRA (serum-resistance-associated) gene, which confers resistance to lysis by human serum. In addition, ESs contain ESAGs (expression-site-associated genes), whose functions, with few exceptions, have remained elusive. A bioinformatic analysis of the ESAG5 gene of T. brucei showed that it encodes a protein with two BPI (bactericidal/permeability-increasing protein)/LBP (lipopolysaccharide-binding protein)/PLUNC (palate, lung and nasal epithelium clone)-like domains and that it belongs to a multigene family termed (GR)ESAG5 (gene related to ESAG5). Members of this family are found with various copy number in different members of the Trypanosomatidae family. T. brucei has an expanded repertoire, with multiple ESAG5 copies and at least five GRESAG5 genes. In contrast, the parasites of the genus Leishmania, which are intracellular parasites, have only a single GRESAG5 gene. Although the amino acid sequence identity between the (GR)ESAG5 gene products between species is as low as 15-25%, the BPI/LBP/PLUNC-like domain organization and the length of the proteins are highly conserved, and the proteins are predicted to be membrane-anchored or secreted. Current work focuses on the elucidation of possible roles for this gene family in infection. This is likely to provide novel insights into the evolution of the BPI/LBP/PLUNC-like domains.
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Gadelha C, Holden JM, Allison HC, Field MC. Specializations in a successful parasite: what makes the bloodstream-form African trypanosome so deadly? Mol Biochem Parasitol 2011; 179:51-8. [PMID: 21763356 DOI: 10.1016/j.molbiopara.2011.06.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Revised: 06/14/2011] [Accepted: 06/15/2011] [Indexed: 12/24/2022]
Abstract
Most trypanosomatid parasites have both arthropod and mammalian or plant hosts, and the ability to survive and complete a developmental program in each of these very different environments is essential for life cycle progression and hence being a successful pathogen. For African trypanosomes, where the mammalian stage is exclusively extracellular, this presents specific challenges and requires evasion of both the acquired and innate immune systems, together with adaptation to a specific nutritional environment and resistance to mechanical and biochemical stresses. Here we consider the basis for these adaptations, the specific features of the mammalian infective trypanosome that are required to meet these challenges, and how these processes both inform on basic parasite biology and present potential therapeutic targets.
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Ray PE, Hu CAA. Advances in our understanding of the pathogenesis of HIV-1 associated nephropathy in children. Future Virol 2011; 6:883-894. [PMID: 22162721 DOI: 10.2217/fvl.11.57] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Childhood HIV-1 associated nephropathy (HIVAN) is a clinical and renal histological disease characterized by heavy proteinuria associated with focal and segmental glomerular sclerosis and/or mesangial hyperplasia in combination with microcystic tubular dilatation. These lesions lead to renal enlargement and rapid progression to kidney failure. Children of African ancestry have a unique susceptibility to developing HIVAN. It is estimated that approximately 300,000 HIV-infected children living in the sub-Saharan Africa could develop HIVAN if they do not receive appropriate antiretroviral therapy. This article discusses recent developments and controversies related to the pathogenesis of childhood HIVAN. The role of host genetic factors, including the newly identified variants in the APOL1 gene, is discussed in the context of previous studies that established the pathological paradigm for HIVAN, and our current understanding of the functional genomics analysis. Hopefully, these advances will provide new research opportunities to generate better treatments for children with HIVAN.
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Affiliation(s)
- Patricio E Ray
- Children's National Medical Center & Department of Pediatrics, The George Washington University School of Medicine & Health Sciences, Washington, DC, USA
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Šíma M, Havelková H, Quan L, Svobodová M, Jarošíková T, Vojtíšková J, Stassen APM, Demant P, Lipoldová M. Genetic control of resistance to Trypanosoma brucei brucei infection in mice. PLoS Negl Trop Dis 2011; 5:e1173. [PMID: 21666791 PMCID: PMC3110168 DOI: 10.1371/journal.pntd.0001173] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Accepted: 04/04/2011] [Indexed: 11/29/2022] Open
Abstract
Background Trypanosoma brucei brucei infects livestock, with severe effects in horses and dogs. Mouse strains differ greatly in susceptibility to this parasite. However, no genes controlling these differences were mapped. Methods We studied the genetic control of survival after T. b. brucei infection using recombinant congenic (RC) strains, which have a high mapping power. Each RC strain of BALB/c-c-STS/A (CcS/Dem) series contains a different random subset of 12.5% genes from the parental “donor” strain STS/A and 87.5% genes from the “background” strain BALB/c. Although BALB/c and STS/A mice are similarly susceptible to T. b. brucei, the RC strain CcS-11 is more susceptible than either of them. We analyzed genetics of survival in T. b. brucei-infected F2 hybrids between BALB/c and CcS-11. CcS-11 strain carries STS-derived segments on eight chromosomes. They were genotyped in the F2 hybrid mice and their linkage with survival was tested by analysis of variance. Results We mapped four Tbbr (Trypanosoma brucei brucei response) loci that influence survival after T. b. brucei infection. Tbbr1 (chromosome 3) and Tbbr2 (chromosome 12) have effects on survival independent of inter-genic interactions (main effects). Tbbr3 (chromosome 7) influences survival in interaction with Tbbr4 (chromosome 19). Tbbr2 is located on a segment 2.15 Mb short that contains only 26 genes. Conclusion This study presents the first identification of chromosomal loci controlling susceptibility to T. b. brucei infection. While mapping in F2 hybrids of inbred strains usually has a precision of 40–80 Mb, in RC strains we mapped Tbbr2 to a 2.15 Mb segment containing only 26 genes, which will enable an effective search for the candidate gene. Definition of susceptibility genes will improve the understanding of pathways and genetic diversity underlying the disease and may result in new strategies to overcome the active subversion of the immune system by T. b. brucei. Trypanosoma brucei are extracellular protozoa transmitted to mammalian host by the tsetse fly. They developed several mechanisms that subvert host's immune defenses. Therefore analysis of genes affecting host's resistance to infection can reveal critical aspects of host-parasite interactions. Trypanosoma brucei brucei infects many animal species including livestock, with particularly severe effects in horses and dogs. Mouse strains differ greatly in susceptibility to T. b. brucei. However, genes controlling susceptibility to this parasite have not been mapped. We analyzed the genetic control of survival after T. b. brucei infection using CcS/Dem recombinant congenic (RC) strains, each of which contains a different random set of 12.5% genes of their donor parental strain STS/A on the BALB/c genetic background. The RC strain CcS-11 is even more susceptible to parasites than BALB/c or STS/A. In F2 hybrids between BALB/c and CcS-11 we detected and mapped four loci, Tbbr1-4 (Trypanosoma brucei brucei response 1–4), that control survival after T. b. brucei infection. Tbbr1 (chromosome 3) and Tbbr2 (chromosome 12) have independent effects, Tbbr3 (chromosome 7) and Tbbr4 (chromosome 19) were detected by their mutual inter-genic interaction. Tbbr2 was precision mapped to a segment of 2.15 Mb that contains 26 genes.
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Affiliation(s)
- Matyáš Šíma
- Laboratory of Molecular and Cellular Immunology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Helena Havelková
- Laboratory of Molecular and Cellular Immunology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Lei Quan
- Roswell Park Cancer Institute, Buffalo, New York, United States of America
| | | | - Taťána Jarošíková
- Faculty of Biomedical Engineering, Czech Technical University in Prague, Kladno, Czech Republic
| | - Jarmila Vojtíšková
- Laboratory of Molecular and Cellular Immunology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Alphons P. M. Stassen
- Department of Genetics and Cell Biology/Clinical Genetics, Maastricht University, Maastricht, The Netherlands
| | - Peter Demant
- Roswell Park Cancer Institute, Buffalo, New York, United States of America
| | - Marie Lipoldová
- Laboratory of Molecular and Cellular Immunology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
- * E-mail:
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Gordon SM, Hofmann S, Askew DS, Davidson WS. High density lipoprotein: it's not just about lipid transport anymore. Trends Endocrinol Metab 2011; 22:9-15. [PMID: 21067941 PMCID: PMC3036841 DOI: 10.1016/j.tem.2010.10.001] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 10/05/2010] [Accepted: 10/05/2010] [Indexed: 12/12/2022]
Abstract
Plasma levels of high density lipoprotein cholesterol (HDL-C) have long been associated with protection against cardiovascular disease (CVD) in large populations. However, HDL-C has been significantly less useful for predicting CVD risk in individual patients. This has ignited a new debate on the merits of measuring HDL quantity versus quality in terms of protective potential. In addition, numerous recent studies have begun to uncover HDL functions that vary surprisingly from traditional lipid transport roles. In this paper, we review recent findings that point to important functions for HDL that go well beyond lipid transport. These discoveries suggest that HDL might be a platform that mediates protection from a host of disease states ranging from CVD to diabetes to infectious disease.
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Affiliation(s)
- Scott M Gordon
- Center for Lipid and Arteriosclerosis Science, University of Cincinnati, 2120 East Galbraith Road, Cincinnati, OH 45237-0507, USA
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