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1.
PLoS One ; 18(11): e0293879, 2023.
Article in English | MEDLINE | ID: mdl-37943810

ABSTRACT

Science, technology, engineering, mathematics, and medicine (STEMM) fields change rapidly and are increasingly interdisciplinary. Commonly, STEMM practitioners use short-format training (SFT) such as workshops and short courses for upskilling and reskilling, but unaddressed challenges limit SFT's effectiveness and inclusiveness. Education researchers, students in SFT courses, and organizations have called for research and strategies that can strengthen SFT in terms of effectiveness, inclusiveness, and accessibility across multiple dimensions. This paper describes the project that resulted in a consensus set of 14 actionable recommendations to systematically strengthen SFT. A diverse international group of 30 experts in education, accessibility, and life sciences came together from 10 countries to develop recommendations that can help strengthen SFT globally. Participants, including representation from some of the largest life science training programs globally, assembled findings in the educational sciences and encompassed the experiences of several of the largest life science SFT programs. The 14 recommendations were derived through a Delphi method, where consensus was achieved in real time as the group completed a series of meetings and tasks designed to elicit specific recommendations. Recommendations cover the breadth of SFT contexts and stakeholder groups and include actions for instructors (e.g., make equity and inclusion an ethical obligation), programs (e.g., centralize infrastructure for assessment and evaluation), as well as organizations and funders (e.g., professionalize training SFT instructors; deploy SFT to counter inequity). Recommendations are aligned with a purpose-built framework-"The Bicycle Principles"-that prioritizes evidenced-based teaching, inclusiveness, and equity, as well as the ability to scale, share, and sustain SFT. We also describe how the Bicycle Principles and recommendations are consistent with educational change theories and can overcome systemic barriers to delivering consistently effective, inclusive, and career-spanning SFT.


Subject(s)
Students , Technology , Humans , Consensus , Engineering
2.
mBio ; 12(6): e0176621, 2021 12 21.
Article in English | MEDLINE | ID: mdl-34872348

ABSTRACT

The crucial transmission phase of tuberculosis (TB) relies on infectious sputum and yet cannot easily be modeled. We applied one-step RNA sequencing (RNA-Seq) to sputum from infectious TB patients to investigate the host and microbial environments underlying transmission of Mycobacterium tuberculosis. In such TB sputa, compared to non-TB controls, transcriptional upregulation of inflammatory responses, including an interferon-driven proinflammatory response and a metabolic shift toward glycolysis, was observed in the host. Among all bacterial sequences in the sputum, approximately 1.5% originated from M. tuberculosis, and its transcript abundance was lower in HIV-1-coinfected patients. Commensal bacterial abundance was reduced in the presence of M. tuberculosis infection. Direct alignment to the genomes of the predominant microbiota species also reveals differential adaptation, whereby firmicutes (e.g., streptococci) displayed a nonreplicating phenotype with reduced transcription of ribosomal proteins and reduced activities of ATP synthases, while Neisseria and Prevotella spp. were less affected. The transcriptome of sputum M. tuberculosis more closely resembled aerobic replication and shared similarity in carbon metabolism to in vitro and in vivo models with significant upregulation of genes associated with cholesterol metabolism and downstream propionate detoxification pathways. In addition, and counter to previous reports on intracellular M. tuberculosis infection in vitro, M. tuberculosis in sputum was zinc, but not iron, deprived, and the phoP loci were also significantly downregulated, suggesting that the pathogen is likely extracellular in location. IMPORTANCE Although a few studies have described the microbiome composition of TB sputa based on 16S ribosomal DNA, these studies did not compare to non-TB samples and the nature of the method does not allow any functional inference. This is the first study to apply such technology using clinical specimens and obtained functional transcriptional data on all three aspects simultaneously. We anticipate that an improved understanding on the biological interactions in the respiratory tract may also allow novel interventions, such as those involving microbiome manipulation or inhibitor targeting disease-specific metabolic pathways.


Subject(s)
Bacteria/genetics , Cholesterol/metabolism , Microbiota , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/metabolism , Sputum/microbiology , Tuberculosis, Pulmonary/microbiology , Bacteria/classification , Bacteria/isolation & purification , Bacteria/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Humans , Mycobacterium tuberculosis/classification , Mycobacterium tuberculosis/isolation & purification , Sputum/chemistry , Transcriptome
3.
F1000Res ; 92020.
Article in English | MEDLINE | ID: mdl-33145007

ABSTRACT

Background: Biocuration involves a variety of teams and individuals across the globe. However, they may not self-identify as biocurators, as they may be unaware of biocuration as a career path or because biocuration is only part of their role. The lack of a clear, up-to-date profile of biocuration creates challenges for organisations like ELIXIR, the ISB and GOBLET to systematically support biocurators and for biocurators themselves to develop their own careers. Therefore, the ELIXIR Training Platform launched an Implementation Study in order to i) identify communities of biocurators, ii) map the type of curation work being done, iii) assess biocuration training, and iv) draw a picture of biocuration career development. Methods: To achieve the goals of the study, we carried out a global survey on the nature of biocuration work, the tools and resources that are used, training that has been received and additional training needs. To examine these topics in more detail we ran workshop-based discussions at ISB Biocuration Conference 2019 and the ELIXIR All Hands Meeting 2019. We also had guided conversations with selected people from the EMBL-European Bioinformatics Institute. Results: The study illustrates that biocurators have diverse job titles, are highly skilled, perform a variety of activities and use a wide range of tools and resources. The study emphasises the need for training in programming and coding skills, but also highlights the difficulties curators face in terms of career development and community building. Conclusion: Biocurators themselves, as well as organisations like ELIXIR, GOBLET and ISB must work together towards structural change to overcome these difficulties. In this article we discuss recommendations to ensure that biocuration as a role is visible and valued, thereby helping biocurators to proceed with their career.


Subject(s)
Computational Biology , Data Curation/methods , Data Mining , Humans
4.
PLoS Comput Biol ; 16(5): e1007854, 2020 05.
Article in English | MEDLINE | ID: mdl-32437350

ABSTRACT

Everything we do today is becoming more and more reliant on the use of computers. The field of biology is no exception; but most biologists receive little or no formal preparation for the increasingly computational aspects of their discipline. In consequence, informal training courses are often needed to plug the gaps; and the demand for such training is growing worldwide. To meet this demand, some training programs are being expanded, and new ones are being developed. Key to both scenarios is the creation of new course materials. Rather than starting from scratch, however, it's sometimes possible to repurpose materials that already exist. Yet finding suitable materials online can be difficult: They're often widely scattered across the internet or hidden in their home institutions, with no systematic way to find them. This is a common problem for all digital objects. The scientific community has attempted to address this issue by developing a set of rules (which have been called the Findable, Accessible, Interoperable and Reusable [FAIR] principles) to make such objects more findable and reusable. Here, we show how to apply these rules to help make training materials easier to find, (re)use, and adapt, for the benefit of all.


Subject(s)
Computer-Assisted Instruction/standards , Guidelines as Topic , Biology/education , Computational Biology , Humans , Information Storage and Retrieval
5.
Int J Parasitol ; 46(4): 239-52, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26812024

ABSTRACT

For hepatic schistosomiasis the egg-induced granulomatous response and the development of extensive fibrosis are the main pathologies. We used a Schistosoma japonicum-infected mouse model to characterise the multi-cellular pathways associated with the recovery from hepatic fibrosis following clearance of the infection with the anti-schistosomal drug, praziquantel. In the recovering liver splenomegaly, granuloma density and liver fibrosis were all reduced. Inflammatory cell infiltration into the liver was evident, and the numbers of neutrophils, eosinophils and macrophages were significantly decreased. Transcriptomic analysis revealed the up-regulation of fatty acid metabolism genes and the identification of Peroxisome proliferator activated receptor alpha as the upstream regulator of liver recovery. The aryl hydrocarbon receptor signalling pathway which regulates xenobiotic metabolism was also differentially up-regulated. These findings provide a better understanding of the mechanisms associated with the regression of hepatic schistosomiasis.


Subject(s)
Anthelmintics/therapeutic use , Granuloma/drug therapy , Liver/pathology , Praziquantel/therapeutic use , Schistosomiasis japonica/drug therapy , Animals , Disease Models, Animal , Eosinophils/pathology , Female , Granuloma/pathology , Immunohistochemistry , Liver/drug effects , Macrophages/pathology , Mice , Mice, Inbred C57BL , Microarray Analysis , Neutrophils/pathology , RNA, Helminth/isolation & purification , Real-Time Polymerase Chain Reaction , Schistosoma japonicum/genetics , Schistosoma japonicum/isolation & purification , Schistosomiasis japonica/pathology , Spleen/pathology , Treatment Outcome , Up-Regulation
6.
Parasitology ; 142(12): 1453-68, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26216487

ABSTRACT

Schistosomiasis is a significant cause of human morbidity and mortality. We performed a genome-wide transcriptional survey of liver biopsies obtained from Chinese patients with chronic schistosomiasis only, or chronic schistosomiasis with a current or past history of viral hepatitis B. Both disease groups were compared with patients with no prior history or indicators of any liver disease. Analysis showed in the main, downregulation in gene expression, particularly those involved in signal transduction via EIF2 signalling and mTOR signalling, as were genes associated with cellular remodelling. Focusing on immune associated pathways, genes were generally downregulated. However, a set of three genes associated with granulocytes, MMP7, CLDN7, CXCL6 were upregulated. Differential gene profiles unique to schistosomiasis included the gene Granulin which was decreased despite being generally considered a marker for liver disease, and IGBP2 which is associated with increased liver size, and was the most upregulated gene in schistosomiasis only patients, all of which presented with hepatomegaly. The unique features of gene expression, in conjunction with previous reports in the murine model of the cellular composition of granulomas, granuloma formation and recovery, provide an increased understanding of the molecular immunopathology and general physiological processes underlying hepatic schistosomiasis.


Subject(s)
Gene Expression Regulation , Liver Cirrhosis/physiopathology , Schistosoma japonicum/immunology , Schistosomiasis japonica/physiopathology , Signal Transduction , Adult , Aged , Animals , Chronic Disease , Down-Regulation , Female , Gene Expression Profiling , Humans , Liver/immunology , Liver/metabolism , Liver Cirrhosis/immunology , Liver Cirrhosis/metabolism , Male , Metabolic Networks and Pathways , Middle Aged , Oligonucleotide Array Sequence Analysis , Schistosomiasis japonica/immunology , Schistosomiasis japonica/metabolism , Schistosomiasis japonica/parasitology , Up-Regulation , Young Adult
7.
Cell Microbiol ; 16(11): 1666-77, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24898449

ABSTRACT

Neutrophils contribute to the pathological processes of a number of inflammatory disorders, including rheumatoid arthritis, sepsis and cystic fibrosis. Neutrophils also play prominent roles in schistosomiasis japonica liver fibrosis, being central mediators of inflammation following granuloma formation. In this study, we investigated the interaction between Schistosoma japonicum eggs and neutrophils, and the effect of eggs on the inflammatory phenotype of neutrophils. Our results showed significant upregulated expression of pro-inflammatory cytokines (IL-1α, IL-1ß and IL-8) and chemokines (CCL3, CCL4 and CXCL2) in neutrophils after 4 h in vitro stimulation with S. japonicum eggs. Furthermore, mitochondrial DNA was released by stimulated neutrophils, and induced the production of matrix metalloproteinase 9 (MMP-9), a protease involved in inflammation and associated tissue destruction. We also found that intact live eggs and isolated soluble egg antigen (SEA) triggered the release of neutrophil extracellular traps (NETs), but, unlike those reported in bacterial or fungal infection, NETs did not kill schistosome eggs in vitro. Together these show that S. japonicum eggs can induce the inflammatory phenotype of neutrophils, and further our understanding of the host-parasite interplay that takes place within the in vivo microenvironment of schistosome-induced granuloma. These findings represent novel findings in a metazoan parasite, and confirm characteristics of NETs that have until now, only been observed in response to protozoan pathogens.


Subject(s)
Cytokines/biosynthesis , Host-Parasite Interactions , Neutrophils/immunology , Neutrophils/parasitology , Schistosoma japonicum/immunology , Zygote/immunology , Animals , Time Factors , Up-Regulation
8.
Trends Parasitol ; 30(3): 141-50, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24433721

ABSTRACT

In hepatic schistosomiasis, pathology arises when schistosome eggs become lodged in the host liver, evoking an interleukin 4 (IL-4)- and IL-13-mediated dominant CD4(+) Th2 immune response. This response leads to the development of granulomas and fibrosis, with eosinophils, neutrophils, macrophages, hepatic stellate cells, and lymphocytes all identified as major cellular contributors to these events. This review outlines the cellular and molecular mechanisms of hepatic schistosomiasis, with an emphasis on the major cellular components and their release of chemokines. The differences between Schistosoma mansoni- and Schistosoma japonicum-induced hepatic granuloma are also discussed. This comprehensive overview of the processes associated with hepatic schistosomiasis may provide new insights into improved treatment for both schistosomiasis and other granulofibrotic diseases.


Subject(s)
Chemokines/immunology , Liver/immunology , Liver/pathology , Schistosomiasis/immunology , Schistosomiasis/pathology , Animals , Granuloma/etiology , Humans , Schistosoma/immunology , Schistosoma japonicum/immunology , Schistosoma mansoni/immunology , Schistosomiasis/complications , Schistosomiasis japonica/complications , Schistosomiasis japonica/immunology , Schistosomiasis japonica/pathology , Schistosomiasis mansoni/complications , Schistosomiasis mansoni/immunology , Schistosomiasis mansoni/pathology
9.
Innate Immun ; 20(5): 501-10, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24045338

ABSTRACT

Many modern vaccines use defined adjuvants to stimulate the innate immune system and shape the adaptive immune response. The exact nature of these innate signals and whether immune differentiation can originate within the periphery is not known. Here we used an ovine lymphatic cannulation model to characterise the cellular and transcriptomic profile of the afferent lymph following injection of a liposomal vaccine formulation incorporating diphtheria toxoid and the innate stimulator poly(I:C) over a 78-h period. The response to this vaccine featured an early activation of broad pro-inflammatory pathways (e.g. TLR signalling and inflammasome pathways) and the transient recruitment of granulocytes into the lymph. At 24 h a more monocytic cellular profile arose coinciding with a transition to a specific antiviral response characterised by the up-regulation of genes associated with the receptors typical for the viral mimic, poly(I:C) (e.g. TLR3, RIG-I and MDA5). At the latest time points the up-regulation of IL-17A and IL-17F suggested that Th17 cells may participate in the earliest adaptive response to this vaccine. These data provide the most comprehensive picture of the cellular and molecular mechanisms that link the periphery to the draining lymph node following vaccination, and indicate that the immune response is capable of specialising within the periphery.


Subject(s)
Antiviral Agents/pharmacology , Immunity, Innate/drug effects , Liposomes , Lymph/immunology , Poly I-C/immunology , Poly I-C/pharmacology , Vaccination , Animals , Diphtheria Toxoid/pharmacology , Granulocytes/immunology , Immunity, Innate/immunology , Inflammasomes/drug effects , Interleukin-17/biosynthesis , Sheep , Th17 Cells , Toll-Like Receptors , Up-Regulation/drug effects
10.
J Leukoc Biol ; 94(2): 353-65, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23709687

ABSTRACT

The severity of schistosome egg-induced hepatic granulomatous pathology depends markedly on the nature of the host immune responses. In this study, we used LMM and microarray analysis to compare gene expression profiles of histologically distinct zones within, and directly proximal to, hepatic granulomas that developed in C57BL/6 mice infected with Schistosoma japonicum. There was significant up-regulation of type-1, type-2, and type-17 immune-associated genes within the granuloma core (adjacent to eggs), followed by increased expression of type-2 and fibrotic genes at the outer zones of granulomas. Neutrophil-associated genes were also found to be expressed differentially in the core and at the peripheral zone of granulomas, present at 7 weeks p.i., demonstrating a significant role of neutrophils in S. japonicum granulomatous pathology. The release of NETs was observed microscopically in granulomas obtained from the livers of infected mice and when human neutrophils were incubated in vitro in the presence of S. japonicum eggs. These finding are the first to suggest a novel, dual role for neutrophils in the mediation of tissue damage and repair in S. japonicum egg-induced hepatic granulomatous lesions. Together, these results provide an overview of the local events occurring within the granuloma microenvironment.


Subject(s)
Extracellular Matrix Proteins/biosynthesis , Gene Expression Profiling , Granuloma/genetics , Host-Parasite Interactions/genetics , Liver Diseases/genetics , Lymphokines/biosynthesis , Neutrophils/physiology , Schistosoma japonicum/physiology , Schistosomiasis japonica/genetics , Transcriptome , Animals , Chemokines/biosynthesis , Chemokines/genetics , Extracellular Matrix/ultrastructure , Extracellular Matrix Proteins/genetics , Female , Granuloma/immunology , Granuloma/metabolism , Granuloma/parasitology , Granuloma/pathology , Host-Parasite Interactions/immunology , Humans , Intercellular Signaling Peptides and Proteins/biosynthesis , Intercellular Signaling Peptides and Proteins/genetics , Liver Diseases/immunology , Liver Diseases/metabolism , Liver Diseases/parasitology , Liver Diseases/pathology , Lymphokines/genetics , Mice , Mice, Inbred C57BL , Microscopy, Confocal , Neutrophils/ultrastructure , Ovum , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Schistosomiasis japonica/immunology , Schistosomiasis japonica/metabolism , Schistosomiasis japonica/pathology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , Up-Regulation
11.
Mol Immunol ; 49(1-2): 191-200, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21917316

ABSTRACT

The migrating schistosomulum is an important stage of the schistosome lifecycle and represents a key target for elimination of infection by natural and vaccine-induced host immune responses. To gain a better understanding of how schistosomes initiate a primary host immune response we have characterised the host lung response to migrating Schistosoma japonicum schistosomula using a combination of histopathology, microarray analysis and real-time PCR. Our findings indicate that the early pulmonary response to these migrating larvae is characteristic of innate inflammation and wound healing. This response is associated with significant up-regulation of several genes with immunoregulatory function including Ch25h, Hmox1 and Retnla which may act to control the nature or magnitude of the inflammatory response to the migrating schistosomula, promoting both parasite and host survival. These findings contribute to our understanding of host-parasite interactions associated with schistosome and, especially, S. japonicum infection, and may aid the future design of novel vaccines that target the lung stage schistosomulum.


Subject(s)
Host-Parasite Interactions/immunology , Immunity, Innate , Lung Diseases, Parasitic/immunology , Schistosoma japonicum/physiology , Schistosomiasis japonica/immunology , Wound Healing/immunology , Animals , Female , Gene Expression Profiling , Host-Parasite Interactions/genetics , Lung Diseases, Parasitic/genetics , Mice , Mice, Inbred C57BL , Oligonucleotide Array Sequence Analysis , Real-Time Polymerase Chain Reaction , Schistosomiasis japonica/genetics , Wound Healing/genetics
12.
PLoS Negl Trop Dis ; 5(6): e1178, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21666794

ABSTRACT

The pathological outcomes of schistosomiasis are largely dependent on the molecular and cellular mechanisms of the host immune response. In this study, we investigated the contribution of variations in host gene expression to the contrasting hepatic pathology observed between two inbred mouse strains following Schistosoma japonicum infection. Whole genome microarray analysis was employed in conjunction with histological and immunohistochemical analysis to define and compare the hepatic gene expression profiles and cellular composition associated with the hepatopathology observed in S. japonicum-infected BALB/c and CBA mice. We show that the transcriptional profiles differ significantly between the two mouse strains with high statistical confidence. We identified specific genes correlating with the more severe pathology associated with CBA mice, as well as genes which may confer the milder degree of pathology associated with BALB/c mice. In BALB/c mice, neutrophil genes exhibited striking increases in expression, which coincided with the significantly greater accumulation of neutrophils at granulomatous regions seen in histological sections of hepatic tissue. In contrast, up-regulated expression of the eosinophil chemokine CCL24 in CBA mice paralleled the cellular influx of eosinophils to the hepatic granulomas. Additionally, there was greater down-regulation of genes involved in metabolic processes in CBA mice, reflecting the more pronounced hepatic damage in these mice. Profibrotic genes showed similar levels of expression in both mouse strains, as did genes associated with Th1 and Th2 responses. However, imbalances in expression of matrix metalloproteinases (e.g. MMP12, MMP13) and tissue inhibitors of metalloproteinases (TIMP1) may contribute to the contrasting pathology observed in the two strains. Overall, these results provide a more complete picture of the molecular and cellular mechanisms which govern the pathological outcome of hepatic schistosomiasis. This improved understanding of the immunopathogenesis in the murine model schistosomiasis provides the basis for a better appreciation of the complexities associated with chronic human schistosomiasis.


Subject(s)
Chemokines/biosynthesis , Gene Expression Regulation , Liver/pathology , Matrix Metalloproteinases, Secreted/biosynthesis , Schistosoma japonicum/pathogenicity , Schistosomiasis japonica/pathology , Animals , Chemokines/genetics , Disease Models, Animal , Eosinophils/immunology , Female , Gene Expression Profiling , Histocytochemistry , Immunohistochemistry , Liver/immunology , Liver/parasitology , Matrix Metalloproteinases, Secreted/genetics , Metabolic Networks and Pathways , Mice , Mice, Inbred BALB C , Mice, Inbred CBA , Microarray Analysis , Neutrophils/immunology , Rodent Diseases/immunology , Rodent Diseases/parasitology , Rodent Diseases/pathology , Schistosoma japonicum/immunology , Schistosomiasis japonica/immunology , Schistosomiasis japonica/parasitology
13.
Hum Pathol ; 42(1): 111-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20970162

ABSTRACT

We present the preoperative findings of 102 patients who underwent successful splenectomy for advanced schistosomiasis japonica. All patients were symptomatic for schistosomiasis and had splenomegaly greater than or equal to II according to the Hackett criteria. Before surgery, all patients underwent clinical examination including full blood count; fibrinogen and serum protein levels; liver function tests; and serology for hepatitis B, C, and D. Ultrasound examination of the liver and spleen and liver histology for evidence of pathology were also undertaken. Ninety patients had a treatment history for schistosomiasis. Fifty-six patients were seropositive for hepatitis B virus antibody, and 6 patients were seropositive for hepatitis C virus antibody. Immunohistochemical testing of the liver samples confirmed that 45 patients were positive for hepatitis B virus surface antigen, thereby indicating active infection. A total of 66.7% of patients had fibrosis stages II to III by ultrasound; and 76.5% of patients had portal vein inner diameter greater than 12 mm, indicating portal vein hypertension. A total of 83.2% of patients showed various stages of esophageal varicosis via x-ray, and 81.4% had fibrotic stages III to IV by liver biopsy. Coinfection with hepatitis B virus accelerated the development of liver fibrosis. There was moderate concordance between the fibrosis assessed by ultrasonography and histopathology, indicating that ultrasound underestimates the true pathology. Combined assessment is needed to improve the diagnosis of clinical hepatic fibrosis.


Subject(s)
Liver Cirrhosis/pathology , Liver Diseases, Parasitic/pathology , Liver/pathology , Schistosomiasis japonica/pathology , Splenic Diseases/pathology , Adolescent , Adult , Aged , Female , Hepatitis B/complications , Hepatitis B/pathology , Humans , Liver/diagnostic imaging , Liver Cirrhosis/diagnostic imaging , Liver Diseases, Parasitic/diagnostic imaging , Liver Diseases, Parasitic/surgery , Male , Middle Aged , Schistosomiasis japonica/complications , Schistosomiasis japonica/diagnostic imaging , Schistosomiasis japonica/surgery , Splenectomy , Splenic Diseases/surgery , Ultrasonography
14.
PLoS Negl Trop Dis ; 4(5): e686, 2010 May 18.
Article in English | MEDLINE | ID: mdl-20502518

ABSTRACT

Determining the molecular events induced in the spleen during schistosome infection is an essential step in better understanding the immunopathogenesis of schistosomiasis and the mechanisms by which schistosomes modulate the host immune response. The present study defines the transcriptional and cellular events occurring in the murine spleen during the progression of Schistosoma japonicum infection. Additionally, we compared and contrasted these results with those we have previously reported for the liver. Microarray analysis combined with flow cytometry and histochemistry demonstrated that transcriptional changes occurring in the spleen were closely related to changes in cellular composition. Additionally, the presence of alternatively activated macrophages, as indicated by up-regulation of Chi3l3 and Chi3l4 and expansion of F4/80(+) macrophages, together with enhanced expression of the immunoregulatory genes ANXA1 and CAMP suggests the spleen may be an important site for the control of S. japonicum-induced immune responses. The most striking difference between the transcriptional profiles of the infected liver and spleen was the contrasting expression of chemokines and cell adhesion molecules. Lymphocyte chemokines, including the homeostatic chemokines CXCL13, CCL19 and CCL21, were significantly down-regulated in the spleen but up-regulated in the liver. Eosinophil (CCL11, CCL24), neutrophil (CXCL1) and monocyte (CXCL14, CCL12) chemokines and the cell adhesion molecules VCAM1, NCAM1, PECAM1 were up-regulated in the liver but unchanged in the spleen. Chemokines up-regulated in both organs were expressed at significantly higher levels in the liver. Co-ordinated expression of these genes probably contributes to the development of a chemotactic signalling gradient that promotes recruitment of effector cells to the liver, thereby facilitating the development of hepatic granulomas and fibrosis. Together these data provide, for the first time, a comprehensive overview of the molecular events occurring in the spleen during schistosomiasis and will substantially further our understanding of the local and systemic mechanisms driving the immunopathogenesis of this disease.


Subject(s)
Cell Movement , Gene Expression , Liver/immunology , Schistosoma japonicum/immunology , Schistosomiasis japonica/pathology , Spleen/pathology , Animals , Cell Adhesion Molecules/biosynthesis , Chemokines/biosynthesis , Female , Flow Cytometry , Histocytochemistry , Leukocytes/immunology , Liver/parasitology , Liver/pathology , Mice , Mice, Inbred C57BL , Oligonucleotide Array Sequence Analysis , Schistosoma japonicum/pathogenicity , Schistosomiasis japonica/immunology , Spleen/immunology , Spleen/parasitology
15.
PLoS Negl Trop Dis ; 4(2): e598, 2010 Feb 09.
Article in English | MEDLINE | ID: mdl-20161726

ABSTRACT

Schistosomiasis continues to be an important cause of parasitic morbidity and mortality world-wide. Determining the molecular mechanisms regulating the development of granulomas and fibrosis will be essential for understanding how schistosome antigens interact with the host environment. We report here the first whole genome microarray analysis of the murine liver during the progression of Schistosoma japonicum egg-induced granuloma formation and hepatic fibrosis. Our results reveal a distinct temporal relationship between the expression of chemokine subsets and the recruitment of cells to the infected liver. Genes up-regulated earlier in the response included T- and B-cell chemoattractants, reflecting the early recruitment of these cells illustrated by flow cytometry. The later phases of the response corresponded with peak recruitment of eosinophils, neutrophils, macrophages and myofibroblasts/hepatic stellate cells (HSCs) and the expression of chemokines with activity for these cells including CCL11 (eotaxin 1), members of the Monocyte-chemoattractant protein family (CCL7, CCL8, CCL12) and the Hepatic Stellate Cell/Fibrocyte chemoattractant CXCL1. Peak expression of macrophage chemoattractants (CCL6, CXCL14) and markers of alternatively activated macrophages (e.g. Retnla) during this later phase provides further evidence of a role for these cells in schistosome-induced pathology. Additionally, we demonstrate that CCL7 immunolocalises to the fibrotic zone of granulomas. Furthermore, striking up-regulation of neutrophil markers and the localisation of neutrophils and the neutrophil chemokine S100A8 to fibrotic areas suggest the involvement of neutrophils in S. japonicum-induced hepatic fibrosis. These results further our understanding of the immunopathogenic and, especially, chemokine signalling pathways that regulate the development of S. japonicum-induced granulomas and fibrosis and may provide correlative insight into the pathogenesis of other chronic inflammatory diseases of the liver where fibrosis is a common feature.


Subject(s)
Chemokines/biosynthesis , Gene Expression Profiling , Liver/immunology , Liver/pathology , Schistosomiasis/immunology , Schistosomiasis/pathology , Animals , Cell Proliferation , Female , Fibroblasts/immunology , Hepatic Stellate Cells/immunology , Leukocytes/immunology , Liver Cirrhosis/immunology , Liver Cirrhosis/pathology , Mice , Mice, Inbred C57BL , Oligonucleotide Array Sequence Analysis
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