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Theobald H, Bejarano DA, Katzmarski N, Haub J, Schulte-Schrepping J, Yu J, Bassler K, Ament AL, Osei-Sarpong C, Piattini F, Vornholz L, T'Jonck W, Györfi AH, Hayer H, Yu X, Sheoran S, Al Jawazneh A, Chakarov S, Haendler K, Brown GD, Williams DL, Bosurgi L, Distler JHW, Ginhoux F, Ruland J, Beyer MD, Greter M, Bain CC, Vazquez-Armendariz AI, Kopf M, Schultze JL, Schlitzer A. Apolipoprotein E controls Dectin-1-dependent development of monocyte-derived alveolar macrophages upon pulmonary β-glucan-induced inflammatory adaptation. Nat Immunol 2024:10.1038/s41590-024-01830-z. [PMID: 38671323 DOI: 10.1038/s41590-024-01830-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 03/27/2024] [Indexed: 04/28/2024]
Abstract
The lung is constantly exposed to the outside world and optimal adaptation of immune responses is crucial for efficient pathogen clearance. However, mechanisms that lead to lung-associated macrophages' functional and developmental adaptation remain elusive. To reveal such mechanisms, we developed a reductionist model of environmental intranasal β-glucan exposure, allowing for the detailed interrogation of molecular mechanisms of pulmonary macrophage adaptation. Employing single-cell transcriptomics, high-dimensional imaging and flow cytometric characterization paired with in vivo and ex vivo challenge models, we reveal that pulmonary low-grade inflammation results in the development of apolipoprotein E (ApoE)-dependent monocyte-derived alveolar macrophages (ApoE+CD11b+ AMs). ApoE+CD11b+ AMs expressed high levels of CD11b, ApoE, Gpnmb and Ccl6, were glycolytic, highly phagocytic and produced large amounts of interleukin-6 upon restimulation. Functional differences were cell intrinsic, and myeloid cell-specific ApoE ablation inhibited Ly6c+ monocyte to ApoE+CD11b+ AM differentiation dependent on macrophage colony-stimulating factor secretion, promoting ApoE+CD11b+ AM cell death and thus impeding ApoE+CD11b+ AM maintenance. In vivo, β-glucan-elicited ApoE+CD11b+ AMs limited the bacterial burden of Legionella pneumophilia after infection and improved the disease outcome in vivo and ex vivo in a murine lung fibrosis model. Collectively these data identify ApoE+CD11b+ AMs generated upon environmental cues, under the control of ApoE signaling, as an essential determinant for lung adaptation enhancing tissue resilience.
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Affiliation(s)
- H Theobald
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - D A Bejarano
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - N Katzmarski
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - J Haub
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - J Schulte-Schrepping
- Genomics & Immunoregulation, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
- Systems Medicine, Deutsches Zentrum für Neurodegenerativen Erkrankungen (DZNE), Bonn, Germany
| | - J Yu
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - K Bassler
- Genomics & Immunoregulation, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - A L Ament
- University of Bonn, Transdisciplinary Research Area Life and Health, Organoid Biology, Life & Medical Sciences Institute, Bonn, Germany
| | - C Osei-Sarpong
- Immunogenomics & Neurodegeneration, German Center for Neurodegenerative Diseases, Bonn, Germany
| | - F Piattini
- Institute of Molecular Health Science, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - L Vornholz
- Institute of Clinical Chemistry and Pathobiochemistry, School of Medicine and Health, Technical University of Munich, Munich, Germany
- TranslaTUM, Center for Translational Cancer Research, Technical University of Munich, Munich, Germany
| | - W T'Jonck
- Centre for Inflammation Research, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh BioQuarter, Edinburgh, UK
| | - A H Györfi
- Department of Rheumatology, University Hospital Düsseldorf, Medical Faculty of Heinrich-Heine University, Düsseldorf, Germany
- Hiller Research Center, University Hospital Düsseldorf, Medical Faculty of Heinrich-Heine University, Düsseldorf, Germany
| | - H Hayer
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - X Yu
- Institute of Experimental Immunology, University of Zurich, Zurich, Switzerland
| | - S Sheoran
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - A Al Jawazneh
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Protozoa Immunology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - S Chakarov
- Shanghai Institute of Immunology, Shanghai JiaoTong School of Medicine, Shanghai, China
| | - K Haendler
- PRECISE Platform for Single Cell Genomics and Epigenomics at DZNE & University of Bonn and West German Genome Center, Bonn, Germany
- Institute of Human Genetics, University Medical Center Schleswig-Holstein, University of Luebeck & Kiel University, Luebeck, Germany
| | - G D Brown
- MRC Centre for Medical Mycology, University of Exeter, Exeter, UK
| | - D L Williams
- Department of Surgery and Center for Inflammation, Infectious Disease and Immunity, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA
| | - L Bosurgi
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Protozoa Immunology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - J H W Distler
- Department of Rheumatology, University Hospital Düsseldorf, Medical Faculty of Heinrich-Heine University, Düsseldorf, Germany
- Hiller Research Center, University Hospital Düsseldorf, Medical Faculty of Heinrich-Heine University, Düsseldorf, Germany
| | - F Ginhoux
- Shanghai Institute of Immunology, Shanghai JiaoTong School of Medicine, Shanghai, China
- Singapore Immunology Network, Agency for Science, Technology and Research, Singapore, Singapore
- INSERM U1015, Gustave Roussy Cancer Campus, Villejuif, France
| | - J Ruland
- Institute of Clinical Chemistry and Pathobiochemistry, School of Medicine and Health, Technical University of Munich, Munich, Germany
- TranslaTUM, Center for Translational Cancer Research, Technical University of Munich, Munich, Germany
- German Center for Infection Research (DZIF), partner site Munich, Munich, Germany
- German Cancer Consortium (DKTK), partner site Munich, Munich, Germany
| | - M D Beyer
- Immunogenomics & Neurodegeneration, German Center for Neurodegenerative Diseases, Bonn, Germany
- PRECISE Platform for Single Cell Genomics and Epigenomics at DZNE & University of Bonn and West German Genome Center, Bonn, Germany
| | - M Greter
- Institute of Experimental Immunology, University of Zurich, Zurich, Switzerland
| | - C C Bain
- Centre for Inflammation Research, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh BioQuarter, Edinburgh, UK
| | - A I Vazquez-Armendariz
- University of Bonn, Transdisciplinary Research Area Life and Health, Organoid Biology, Life & Medical Sciences Institute, Bonn, Germany
| | - M Kopf
- Institute of Molecular Health Science, Department of Biology, ETH Zürich, Zürich, Switzerland
| | - J L Schultze
- Genomics & Immunoregulation, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany
- Systems Medicine, Deutsches Zentrum für Neurodegenerativen Erkrankungen (DZNE), Bonn, Germany
- PRECISE Platform for Single Cell Genomics and Epigenomics at DZNE & University of Bonn and West German Genome Center, Bonn, Germany
| | - A Schlitzer
- Quantitative Systems Biology, Life & Medical Sciences Institute, University of Bonn, Bonn, Germany.
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Baumgartner D, Kopf M, Klähn S, Steglich C, Hess WR. Small proteins in cyanobacteria provide a paradigm for the functional analysis of the bacterial micro-proteome. BMC Microbiol 2016; 16:285. [PMID: 27894276 PMCID: PMC5126843 DOI: 10.1186/s12866-016-0896-z] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 11/14/2016] [Indexed: 12/21/2022] Open
Abstract
Background Despite their versatile functions in multimeric protein complexes, in the modification of enzymatic activities, intercellular communication or regulatory processes, proteins shorter than 80 amino acids (μ-proteins) are a systematically underestimated class of gene products in bacteria. Photosynthetic cyanobacteria provide a paradigm for small protein functions due to extensive work on the photosynthetic apparatus that led to the functional characterization of 19 small proteins of less than 50 amino acids. In analogy, previously unstudied small ORFs with similar degrees of conservation might encode small proteins of high relevance also in other functional contexts. Results Here we used comparative transcriptomic information available for two model cyanobacteria, Synechocystis sp. PCC 6803 and Synechocystis sp. PCC 6714 for the prediction of small ORFs. We found 293 transcriptional units containing candidate small ORFs ≤80 codons in Synechocystis sp. PCC 6803, also including the known mRNAs encoding small proteins of the photosynthetic apparatus. From these transcriptional units, 146 are shared between the two strains, 42 are shared with the higher plant Arabidopsis thaliana and 25 with E. coli. To verify the existence of the respective μ-proteins in vivo, we selected five genes as examples to which a FLAG tag sequence was added and re-introduced them into Synechocystis sp. PCC 6803. These were the previously annotated gene ssr1169, two newly defined genes norf1 and norf4, as well as nsiR6(nitrogen stress-induced RNA 6) and hliR1(high light-inducible RNA 1) , which originally were considered non-coding. Upon activation of expression via the Cu2+.responsive petE promoter or from the native promoters, all five proteins were detected in Western blot experiments. Conclusions The distribution and conservation of these five genes as well as their regulation of expression and the physico-chemical properties of the encoded proteins underline the likely great bandwidth of small protein functions in bacteria and makes them attractive candidates for functional studies.
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Affiliation(s)
- Desiree Baumgartner
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104, Freiburg, Germany
| | - Matthias Kopf
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104, Freiburg, Germany.,Present Address: Molecular Health GmbH, Kurfürsten-Anlage 21, 69115, Heidelberg, Germany
| | - Stephan Klähn
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104, Freiburg, Germany
| | - Claudia Steglich
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104, Freiburg, Germany
| | - Wolfgang R Hess
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104, Freiburg, Germany.
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Stazic D, Pekarski I, Kopf M, Lindell D, Steglich C. A Novel Strategy for Exploitation of Host RNase E Activity by a Marine Cyanophage. Genetics 2016; 203:1149-59. [PMID: 27182944 PMCID: PMC4937493 DOI: 10.1534/genetics.115.183475] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 05/04/2016] [Indexed: 11/18/2022] Open
Abstract
Previous studies have shown that infection of Prochlorococcus MED4 by the cyanophage P-SSP7 leads to increased transcript levels of host endoribonuclease (RNase) E. However, it has remained enigmatic whether this is part of a host defense mechanism to degrade phage messenger RNA (mRNA) or whether this single-strand RNA-specific RNase is utilized by the phage. Here we describe a hitherto unknown means through which this cyanophage increases expression of RNase E during phage infection and concomitantly protects its own RNA from degradation. We identified two functionally different RNase E mRNA variants, one of which is significantly induced during phage infection. This transcript lacks the 5' UTR, is considerably more stable than the other transcript, and is likely responsible for increased RNase E protein levels during infection. Furthermore, selective enrichment and in vivo analysis of double-stranded RNA (dsRNA) during infection revealed that phage antisense RNAs (asRNAs) sequester complementary mRNAs to form dsRNAs, such that the phage protein-coding transcriptome is nearly completely covered by asRNAs. In contrast, the host protein-coding transcriptome is only partially covered by asRNAs. These data suggest that P-SSP7 orchestrates degradation of host RNA by increasing RNase E expression while masking its own transcriptome from RNase E degradation in dsRNA complexes. We propose that this combination of strategies contributes significantly to phage progeny production.
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Affiliation(s)
- Damir Stazic
- Faculty of Biology, University of Freiburg, D-79104 Freiburg, Germany
| | - Irena Pekarski
- Department of Biology, Technion Institute of Technology, Haifa 32000, Israel
| | - Matthias Kopf
- Faculty of Biology, University of Freiburg, D-79104 Freiburg, Germany
| | - Debbie Lindell
- Department of Biology, Technion Institute of Technology, Haifa 32000, Israel
| | - Claudia Steglich
- Faculty of Biology, University of Freiburg, D-79104 Freiburg, Germany
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Shapira I, Naboush A, Banavali A, Neculiseanu E, Guddati K, Kopf M, Mason C, Lee A. 7: INTEGRATED PATHWAY ANALYSIS OF MICRORNA EXPRESSION IN PLASMA OF OVARIAN CANCER (OVCA) PATIENTS SHOWS LACK OF BH3 PROTEIN DEPENDENT SIGNALING. J Investig Med 2016. [DOI: 10.1136/jim-2016-000080.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Purpose of StudyMore than 100,000 pelvic surgeries to remove ovarian masses (BOM) are performed yearly in the USA only 8% of those remove ovarian cancer. Circulating microRNA are biomarkers for disease detection. Purpose of study:1. To analyze patterns of microRNAs in women with BOM vs. OvCa2. Discover pathway involved malignant transformation.Methods UsedPlasma from 32 women OvCa, 24 controls 32 (BOM) was analyzed using ABI Taqman OpenArray MicroRNA pools A and B to measure the expression of 754 known miRNAs .Real-time PCR was performed on the Taqman Open Array MicroRNA arrays using the Applied Biosystem Open Array Real-Time PCR system. Data were processed using the OpenArray Real-Time qPCR Analysis software and exported for analysis using the Applied Biosystems DataAssist Software Data analysis was done with the R programming language. A cutoff for Ct values at 30 was used. MiRNAs with Ct values higher than 30 were considered not detected. Data was normalized using a mean-centering restricted (MCR), a modification of the traditional delta Ct method and uses miRNAs which are expressed in all samples for data normalization. Statistical analysis was performed via custom scripts based on the R/Bioconductor package LIMMA (Linear Models for Microarray).Summary of ResultsBOM had higher expression (2–14 fold higher) of miRs −195, −126, −139-5p, −27b, −127, −152, −28, −106b, −17, −363, −181a, −192 relative to OvCa (p<0.0006). OvCa over-expressed of miRs −1274a, −720 and −625-3p (p<0.0007). Reactome pathway analysis detected involvement of miRs into pathways of activation of BAD, PI3/AKT signaling in CD28 and activation of BH3 in BOM these pathways were not detected in OvCa (p<0.000596).ConclusionsBOM patients have immune recognition and pro-apoptotic protective circulating microRNAs. It is unknown whether miRs originate in ovary or another tissue. Recent work shows that BH3 mimetics are very effective in inducing cancer cell death.
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Shapira I, Daksharam P, Kremer V, Banavali A, Kopf M, Naboush A, Shih A, Mason C, Lee A. P6: CIRCULATING MICRORNA PATTERN DEFINES A BIOLOGICALLY DISTINCT BREAST CANCER PATTERN IN BLACK (B) WOMEN RELATIVE TO ONE CCCURRING IN WHITE (W) WOMEN. J Investig Med 2016. [DOI: 10.1136/jim-2016-000080.46] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Purpose of StudyBlack women with triple negative breast cancer have 46% lower survival rates attributed to differences in tumor biology. We analyzed presurgical plasma microRNA of white (W) and black (B) women with TNBC enrolled in our breast ovarian tissue bank between 2004 and 2014.AimsDetect microRNA patterns in pre-surgical plasma of TNBC W or B
Analyze differences by integrated approach to detect pathways differentially activated in the two groups.Methods UsedBetween 2004 and 2014 we investigated patterns of plasma miRNAs collected before, after surgery, during and after chemotherapy in 67 patients presenting for surgery for breast cancer (W=44 & B=44) and 25 age and race matched normal controls. Two-sample t-test was used for all 2-sample comparison and ANOVA followed by Benjamin Hochberg post-hoc test to compare the mean response between subject factors of interest. All tests were 2-tailed and results with a p<0.05 were considered statistically significant. Coremine was used to identify datasets in breast cancer microarray with emphasis on our differentially expressed circulating miRs.Summary of ResultsMean age cancer 48 (range 35–78), control 44 (range 35–67): B patients did not express over 70% of pre-surgical plasma miRs over-expressed in the W pre-surgical plasma. Black patients had lower expression of MiRs: −16-5p, −484, −126, −150-5p, −142-3p; −30c-5p, −186-5p, 139-5p. Samples from white patients overexpressed miRs−126, −150-5p, −142-3p; −30c-5p, −186-5p, 139-5p compared to healthy controls. These miRs significantly suppressed in blacks p<0.05.Coremine text mining suggests differentially regulated microRNA are involved in mitochondrial quality control and biogenesis.ConclusionsDeregulation in circulating miRs between B and W patients point to pathways involved in mitochondrial fission and fusion. Aberrant mitochondria biogenesis was reported as mechanism for cancer stem cell survival and detrimental to innate immunity. Such pathways could explain the lower survival seen in black breast cancer patients.
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Abstract
Regulatory RNAs play versatile roles in bacteria in the coordination of gene expression
during various physiological processes, especially during stress adaptation.
Photosynthetic bacteria use sunlight as their major energy source. Therefore, they are
particularly vulnerable to the damaging effects of excess light or UV irradiation. In
addition, like all bacteria, photosynthetic bacteria must adapt to limiting nutrient
concentrations and abiotic and biotic stress factors. Transcriptome analyses have
identified hundreds of potential regulatory small RNAs (sRNAs) in model cyanobacteria such
as Synechocystis sp. PCC 6803 or Anabaena sp. PCC 7120,
and in environmentally relevant genera such as Trichodesmium,
Synechococcus and Prochlorococcus. Some sRNAs have
been shown to actually contain μORFs and encode short proteins. Examples include the
40-amino-acid product of the sml0013 gene, which encodes the NdhP subunit
of the NDH1 complex. In contrast, the functional characterization of the non-coding sRNA
PsrR1 revealed that the 131 nt long sRNA controls photosynthetic functions by targeting
multiple mRNAs, providing a paradigm for sRNA functions in photosynthetic bacteria. We
suggest that actuatons comprise a new class of genetic elements in which an sRNA gene is
inserted upstream of a coding region to modify or enable transcription of that region. Hundreds of potentially regulatory small RNAs (sRNAs) have been identified in model
cyanobacteria and, despite recent significant progress, their functional characterization
is substantial work and continues to provide surprising insights of general interest.
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Affiliation(s)
- Matthias Kopf
- Faculty of Biology, Institute of Biology III, University of Freiburg, D-79104 Freiburg, Germany
| | - Wolfgang R Hess
- Faculty of Biology, Institute of Biology III, University of Freiburg, D-79104 Freiburg, Germany
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Kopf M, Klähn S, Scholz I, Hess WR, Voß B. Variations in the non-coding transcriptome as a driver of inter-strain divergence and physiological adaptation in bacteria. Sci Rep 2015; 5:9560. [PMID: 25902393 PMCID: PMC5386190 DOI: 10.1038/srep09560] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 03/05/2015] [Indexed: 12/16/2022] Open
Abstract
In all studied organisms, a substantial portion of the transcriptome consists of non-coding RNAs that frequently execute regulatory functions. Here, we have compared the primary transcriptomes of the cyanobacteria Synechocystis sp. PCC 6714 and PCC 6803 under 10 different conditions. These strains share 2854 protein-coding genes and a 16S rRNA identity of 99.4%, indicating their close relatedness. Conserved major transcriptional start sites (TSSs) give rise to non-coding transcripts within the sigB gene, from the 5′UTRs of cmpA and isiA, and 168 loci in antisense orientation. Distinct differences include single nucleotide polymorphisms rendering promoters inactive in one of the strains, e.g., for cmpR and for the asRNA PsbA2R. Based on the genome-wide mapped location, regulation and classification of TSSs, non-coding transcripts were identified as the most dynamic component of the transcriptome. We identified a class of mRNAs that originate by read-through from an sRNA that accumulates as a discrete and abundant transcript while also serving as the 5′UTR. Such an sRNA/mRNA structure, which we name ‘actuaton’, represents another way for bacteria to remodel their transcriptional network. Our findings support the hypothesis that variations in the non-coding transcriptome constitute a major evolutionary element of inter-strain divergence and capability for physiological adaptation.
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Affiliation(s)
- Matthias Kopf
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Stephan Klähn
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Ingeborg Scholz
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Wolfgang R Hess
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
| | - Björn Voß
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany
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Kopf M, Möke F, Bauwe H, Hess WR, Hagemann M. Expression profiling of the bloom-forming cyanobacterium Nodularia CCY9414 under light and oxidative stress conditions. ISME J 2015; 9:2139-52. [PMID: 25689027 DOI: 10.1038/ismej.2015.16] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 01/08/2015] [Indexed: 11/10/2022]
Abstract
Massive blooms of toxic cyanobacteria frequently occur in the central Baltic Sea during the summer. In the surface scum, cyanobacterial cells are exposed to high light (HL) intensity, high oxygen partial pressure and other stresses. To mimic these conditions, cultures of Nodularia spumigena CCY9414, which is a strain isolated from a cyanobacterial summer bloom in the Baltic Sea, were incubated at a HL intensity of 1200 μmol photons m(-2) s(-1) or a combination of HL and increased oxygen partial pressure. Using differential RNA sequencing, we compared the global primary transcriptomes of control and stressed cells. The combination of oxidative and light stresses induced the expression of twofold more genes compared with HL stress alone. In addition to the induction of known stress-responsive genes, such as psbA, ocp and sodB, Nodularia cells activated the expression of genes coding for many previously unknown light- and oxidative stress-related proteins. In addition, the expression of non-protein-coding RNAs was found to be stimulated by these stresses. Among them was an antisense RNA to the phycocyanin-encoding mRNA cpcBAC and the trans-encoded regulator of photosystem I, PsrR1. The large genome capacity allowed Nodularia to harbor more copies of stress-relevant genes such as psbA and small chlorophyll-binding protein genes, combined with the coordinated induction of these and many additional genes for stress acclimation. Our data provide a first insight on how N. spumigena became adapted to conditions relevant for a cyanobacterial bloom in the Baltic Sea.
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Affiliation(s)
- Matthias Kopf
- Albert-Ludwigs-Universität Freiburg, Fakultät für Biologie, Genetik und Experimentelle Bioinformatik, Freiburg, Germany
| | - Fred Möke
- Universität Rostock, Institut für Biowissenschaften, Pflanzenphysiologie, Rostock, Germany
| | - Hermann Bauwe
- Universität Rostock, Institut für Biowissenschaften, Pflanzenphysiologie, Rostock, Germany
| | - Wolfgang R Hess
- Albert-Ludwigs-Universität Freiburg, Fakultät für Biologie, Genetik und Experimentelle Bioinformatik, Freiburg, Germany
| | - Martin Hagemann
- Universität Rostock, Institut für Biowissenschaften, Pflanzenphysiologie, Rostock, Germany
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Abstract
RNA-seq and especially differential RNA-seq-type transcriptomic analyses (dRNA-seq) are powerful analytical tools, as they not only provide insights into gene expression changes but also provide detailed information about all promoters active at a given moment, effectively giving a deep insight into the transcriptional landscape. Synechocystis sp. PCC 6803 (Synechocystis 6803) is a unicellular model cyanobacterium that is widely used in research fields from ecology, photophysiology to systems biology, modelling and biotechnology. Here, we analysed the response of the Synechocystis 6803 primary transcriptome to different, environmentally relevant stimuli. We established genome-wide maps of the transcriptional start sites active under 10 different conditions relevant for photosynthetic growth and identified 4,091 transcriptional units, which provide information about operons, 5′ and 3′ untranslated regions (UTRs). Based on a unique expression factor, we describe regulons and relevant promoter sequences at single-nucleotide resolution. Finally, we report several sRNAs with an intriguing expression pattern and therefore likely function, specific for carbon depletion (CsiR1), nitrogen depletion (NsiR4), phosphate depletion (PsiR1), iron stress (IsaR1) or photosynthesis (PsrR1). This dataset is accompanied by comprehensive information providing extensive visualization and data access to allow an easy-to-use approach for the design of experiments, the incorporation into modelling studies of the regulatory system and for comparative analyses.
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Affiliation(s)
- Matthias Kopf
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
| | - Stephan Klähn
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
| | - Ingeborg Scholz
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
| | - Jasper K F Matthiessen
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
| | - Wolfgang R Hess
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
| | - Björn Voß
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, Freiburg 79104, Germany
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Kopf M, Klähn S, Pade N, Weingärtner C, Hagemann M, Voß B, Hess WR. Comparative genome analysis of the closely related Synechocystis strains PCC 6714 and PCC 6803. DNA Res 2014; 21:255-66. [PMID: 24408876 PMCID: PMC4060947 DOI: 10.1093/dnares/dst055] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 11/28/2013] [Indexed: 11/14/2022] Open
Abstract
Synechocystis sp. PCC 6803 is the most popular cyanobacterial model for prokaryotic photosynthesis and for metabolic engineering to produce biofuels. Genomic and transcriptomic comparisons between closely related bacteria are powerful approaches to infer insights into their metabolic potentials and regulatory networks. To enable a comparative approach, we generated the draft genome sequence of Synechocystis sp. PCC 6714, a closely related strain of 6803 (16S rDNA identity 99.4%) that also is amenable to genetic manipulation. Both strains share 2838 protein-coding genes, leaving 845 unique genes in Synechocystis sp. PCC 6803 and 895 genes in Synechocystis sp. PCC 6714. The genetic differences include a prophage in the genome of strain 6714, a different composition of the pool of transposable elements, and a ∼ 40 kb genomic island encoding several glycosyltransferases and transport proteins. We verified several physiological differences that were predicted on the basis of the respective genome sequence. Strain 6714 exhibited a lower tolerance to Zn(2+) ions, associated with the lack of a corresponding export system and a lowered potential of salt acclimation due to the absence of a transport system for the re-uptake of the compatible solute glucosylglycerol. These new data will support the detailed comparative analyses of this important cyanobacterial group than has been possible thus far. Genome information for Synechocystis sp. PCC 6714 has been deposited in Genbank (accession no AMZV01000000).
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Affiliation(s)
- Matthias Kopf
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, D-79104 Freiburg, Germany
| | - Stephan Klähn
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, D-79104 Freiburg, Germany
| | - Nadin Pade
- Plant Physiology, Institute for Life Sciences, University of Rostock, Einsteinstr. 3, D-18059 Rostock, Germany
| | - Christian Weingärtner
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, D-79104 Freiburg, Germany
| | - Martin Hagemann
- Plant Physiology, Institute for Life Sciences, University of Rostock, Einsteinstr. 3, D-18059 Rostock, Germany
| | - Björn Voß
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, D-79104 Freiburg, Germany
| | - Wolfgang R Hess
- Genetics and Experimental Bioinformatics, Faculty of Biology, University of Freiburg, Schänzlestr. 1, D-79104 Freiburg, Germany
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Abstract
Background RNA-seq and its variant differential RNA-seq (dRNA-seq) are today routine methods for transcriptome analysis in bacteria. While expression profiling and transcriptional start site prediction are standard tasks today, the problem of identifying transcriptional units in a genome-wide fashion is still not solved for prokaryotic systems. Results We present RNAseg, an algorithm for the prediction of transcriptional units based on dRNA-seq data. A key feature of the algorithm is that, based on the data, it distinguishes between transcribed and un-transcribed genomic segments. Furthermore, the program provides many different predictions in a single run, which can be used to infer the significance of transcriptional units in a consensus procedure. We show the performance of our method based on a well-studied dRNA-seq data set for Helicobacter pylori. Conclusions With our algorithm it is possible to identify operons and 5’- and 3’-UTRs in an automated fashion. This alleviates the need for labour intensive manual inspection and enables large-scale studies in the area of comparative transcriptomics.
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Affiliation(s)
| | | | - Björn Voß
- Genetics & Experimental Bioinformatics, Institute for Biology 3, Faculty of Biology, Albert-Ludwigs-University Freiburg, Schänzlestr, 1, 79104 Freiburg, Germany.
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Voß B, Bolhuis H, Fewer DP, Kopf M, Möke F, Haas F, El-Shehawy R, Hayes P, Bergman B, Sivonen K, Dittmann E, Scanlan DJ, Hagemann M, Stal LJ, Hess WR. Insights into the physiology and ecology of the brackish-water-adapted Cyanobacterium Nodularia spumigena CCY9414 based on a genome-transcriptome analysis. PLoS One 2013; 8:e60224. [PMID: 23555932 PMCID: PMC3610870 DOI: 10.1371/journal.pone.0060224] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 02/23/2013] [Indexed: 11/18/2022] Open
Abstract
Nodularia spumigena is a filamentous diazotrophic cyanobacterium that dominates the annual late summer cyanobacterial blooms in the Baltic Sea. But N. spumigena also is common in brackish water bodies worldwide, suggesting special adaptation allowing it to thrive at moderate salinities. A draft genome analysis of N. spumigena sp. CCY9414 yielded a single scaffold of 5,462,271 nucleotides in length on which genes for 5,294 proteins were annotated. A subsequent strand-specific transcriptome analysis identified more than 6,000 putative transcriptional start sites (TSS). Orphan TSSs located in intergenic regions led us to predict 764 non-coding RNAs, among them 70 copies of a possible retrotransposon and several potential RNA regulators, some of which are also present in other N2-fixing cyanobacteria. Approximately 4% of the total coding capacity is devoted to the production of secondary metabolites, among them the potent hepatotoxin nodularin, the linear spumigin and the cyclic nodulapeptin. The transcriptional complexity associated with genes involved in nitrogen fixation and heterocyst differentiation is considerably smaller compared to other Nostocales. In contrast, sophisticated systems exist for the uptake and assimilation of iron and phosphorus compounds, for the synthesis of compatible solutes, and for the formation of gas vesicles, required for the active control of buoyancy. Hence, the annotation and interpretation of this sequence provides a vast array of clues into the genomic underpinnings of the physiology of this cyanobacterium and indicates in particular a competitive edge of N. spumigena in nutrient-limited brackish water ecosystems.
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Affiliation(s)
- Björn Voß
- Genetics and Experimental Bioinformatics Group, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Henk Bolhuis
- Department of Marine Microbiology, Royal Netherlands Institute of Sea Research, Yerseke, The Netherlands
| | - David P. Fewer
- Food and Environmental Sciences, Division of Microbiology, Viikki Biocenter, University of Helsinki, Helsinki, Finland
| | - Matthias Kopf
- Genetics and Experimental Bioinformatics Group, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Fred Möke
- Plant Physiology, Institute Biosciences, University of Rostock, Rostock, Germany
| | - Fabian Haas
- Genetics and Experimental Bioinformatics Group, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | | | - Paul Hayes
- Faculty of Science, University of Portsmouth, Portsmouth, United Kingdom
| | | | - Kaarina Sivonen
- Food and Environmental Sciences, Division of Microbiology, Viikki Biocenter, University of Helsinki, Helsinki, Finland
| | - Elke Dittmann
- Institute for Biochemistry and Biology, University of Potsdam, Golm, Germany
| | - Dave J. Scanlan
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Martin Hagemann
- Plant Physiology, Institute Biosciences, University of Rostock, Rostock, Germany
| | - Lucas J. Stal
- Department of Marine Microbiology, Royal Netherlands Institute of Sea Research, Yerseke, The Netherlands
- Department of Aquatic Microbiology, University of Amsterdam, Amsterdam, The Netherlands
| | - Wolfgang R. Hess
- Genetics and Experimental Bioinformatics Group, Faculty of Biology, University of Freiburg, Freiburg, Germany
- * E-mail:
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13
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Freigang S, Ampenberger F, Hersberger M, Kopf M. O041 Predominant role of macrophage-derived IL-1alpha but not IL-1beta in atherosclerosis. Cytokine 2012. [DOI: 10.1016/j.cyto.2012.06.079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Schröder B, Dück R, Kopf M. Untersuchungen zu den mechanischen Eigenschaften von metallischen Gefäßimplantaten (Stents). BIOMED ENG-BIOMED TE 2009. [DOI: 10.1515/bmte.1998.43.s1.436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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15
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Marsland BJ, Scanga CB, Kopf M, Le Gros G. Allergic airway inflammation is exacerbated during acute influenza infection and correlates with increased allergen presentation and recruitment of allergen-specific T-helper type 2 cells. Clin Exp Allergy 2004; 34:1299-306. [PMID: 15298573 DOI: 10.1111/j.1365-2222.2004.02021.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Respiratory viral infections are a leading cause of the hospitalization of asthmatics, however, the cellular immunological interactions which underlie these two diseases remain elusive. OBJECTIVE We sought to characterize the effect influenza viral infection has on allergic airway inflammation and to identify the cellular pathways involved. METHODS We have used an ovalbumin (OVA) model of allergic airway inflammation, which involves sensitization of animals with OVA adsorbed in alum adjuvant followed by an intranasal challenge with OVA in phosphate-buffered saline. To study T cell recruitment into the lung, we adoptively transferred in vitro activated T cell receptor-transgenic T cells, which were subsequently identified by fluorescence-activated cell sorting (FACS) analysis. In addition, to study in vivo dendritic cell (DC) migration, we administered fluorescently labelled dextran and identified DCs that had phagocytosed it by FACS analysis. RESULTS We found that different stages of influenza infection had contrasting effects upon the outcome of OVA-induced allergic airway inflammation. The allergic response against OVA was exacerbated during the acute stage of influenza infection; however, mice were protected against the development of airway eosinophilia at late time-points following infection. We investigated the mechanisms responsible for the virus-induced exacerbation and found that the response was partially independent of IL-4 and that there was increased delivery of inhaled allergens to the draining lymph node during the acute stage of the infection. In addition, virus-induced inflammation in the lung and draining lymph node resulted in the non-specific recruitment of circulating allergen-specific effector/memory cells. CONCLUSION In addition to virus-mediated damage to the lung and airways, influenza viral infection can also enhance unrelated local allergic responses.
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Affiliation(s)
- B J Marsland
- Malaghan Institute of Medical Research, Wellington School of Medicine, Wellington, New Zealand.
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16
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Bachmann MF, Hunziker L, Zinkernagel RM, Storni T, Kopf M. Maintenance of memory CTL responses by T helper cells and CD40-CD40 ligand: antibodies provide the key. Eur J Immunol 2004. [DOI: 10.1002/eji.200490005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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17
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Eriksson U, Kurrer MO, Sebald W, Brombacher F, Kopf M. Dual role of the IL-12/IFN-gamma axis in the development of autoimmune myocarditis: induction by IL-12 and protection by IFN-gamma. J Immunol 2001; 167:5464-9. [PMID: 11673566 DOI: 10.4049/jimmunol.167.9.5464] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
IL-12 and IFN-gamma positively regulate each other and type 1 inflammatory responses, which are believed to cause tissue damage in autoimmune diseases. We investigated the role of the IL-12/IFN-gamma (Th1) axis in the development of autoimmune myocarditis. IL-12p40-deficient mice on a susceptible background resisted myocarditis. In the absence of IL-12, autospecific CD4(+) T cells proliferated poorly and showed increased Th2 cytokine responses. However, IFN-gamma-deficient mice developed fatal autoimmune disease, and blockade of IL-4R signaling did not confer susceptibility to myocarditis in IL-12p40-deficient mice, demonstrating that IL-12 triggers autoimmunity by a mechanism independent of the effector cytokines IFN-gamma and IL-4. In conclusion, our results suggest that the IL-12/IFN-gamma axis is a double-edged sword for the development of autoimmune myocarditis. Although IL-12 mediates disease by induction/expansion of Th1-type cells, IFN-gamma production from these cells limits disease progression.
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Affiliation(s)
- U Eriksson
- Medicine A, University Hospital, and Basel Institute for Immunology, Basel, Switzerland.
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18
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Koller D, Ruedl C, Loetscher M, Vlach J, Oehen S, Oertle K, Schirinzi M, Deneuve E, Moser R, Kopf M, Bailey JE, Renner W, Bachmann MF. A high-throughput alphavirus-based expression cloning system for mammalian cells. Nat Biotechnol 2001; 19:851-5. [PMID: 11533644 DOI: 10.1038/nbt0901-851] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We have developed a widely applicable functional genomics strategy based on alphavirus expression vectors. The technology allows for rapid identification of genes encoding a functional activity such as binding of a defined ligand. Complementary DNA (cDNA) libraries were expressed in mammalian cells following infection with recombinant Sindbis virus (SIN replicon particles), a member of the Alphavirus genus. Virus-infected cells that specifically bound a ligand of choice were isolated using fluorescence-activated cell sorting (FACS). Replication-competent, infective SIN replicon particles harboring the corresponding cDNA were amplified in a next step. Within one round of selection, viral clones encoding proteins recognized by monoclonal antibodies or Fc-fusion molecules could be isolated and sequenced. Moreover, using the same viral libraries, a plaque-lift assay was established that allowed the identification of secreted, intracellular, and membrane proteins.
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Affiliation(s)
- D Koller
- Cytos Biotechnology AG, Wagistr. 21, CH-8952 Schlieren-Zürich, Switzerland
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19
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Wallenius V, Wallenius K, Hisaoka M, Sandstedt J, Ohlsson C, Kopf M, Jansson JO. Retarded liver growth in interleukin-6-deficient and tumor necrosis factor receptor-1-deficient mice. Endocrinology 2001; 142:2953-60. [PMID: 11416016 DOI: 10.1210/endo.142.7.8270] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The liver size in adult mammals is tightly regulated in relation to body weight, but the hormonal control of this is largely unknown. We investigated the roles of interleukin-6 (IL-6) and tumor necrosis factor (TNF) receptor-1 in the regulation of intact liver weight in adult mice. The relative liver wet and dry weights of older adult (5- to 10-month-old) IL-6 knockout (IL-6(-/-)) mice were decreased by 22-28%, and total contents of DNA and protein were decreased compared with those in age-matched wild-type mice. Weights of other visceral organs were unaffected. Older adult (6- to 8-month-old) TNF receptor-1 knockout (TNFR1(-/-)) mice displayed decreased relative liver weight. Treatment with a single injection of IL-6 increased liver wet and dry weights in IL-6(-/-) and wild-type mice, but not TNFR1(-/-) mice. Treatment with TNFalpha enhanced liver weight and DNA synthesis of nonparenchymal liver cells at 24 h in wild-type, but not IL-6(-/-), mice. At 48 h, TNFalpha induced DNA synthesis in nonparenchymal cells and hepatocytes of both wild-type and IL-6(-/-) mice. In conclusion, TNF receptor-1 stimulation and IL-6 production are both necessary for normal liver weight gain in older adult mice. The results of TNFalpha and IL-6 treatment further indicate that the effects of TNF receptor-1 and IL-6 depend on each other for full stimulation of liver growth.
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Affiliation(s)
- V Wallenius
- Research Center for Endocrinology and Metabolism, Department of Internal Medicine, Sahlgrenska University Hospital, SE-413 45 Gothenburg, Sweden.
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20
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Affiliation(s)
- M F Bachmann
- Cytos Biotechnology AG, 8952 Schlieren-Zürich, Switzerland.
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21
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Abstract
BACKGROUND AND OBJECTIVES Lung remodelling is a recognized feature of chronic asthma. In the present study, we have used IL-5-deficient mice to evaluate the role of this cytokine and eosinophilic inflammation in the initial stages of the structural changes occurring in the lung after antigen challenge. METHODS Ovalbumin-sensitized wild type and IL-5-deficient mice were daily challenged for 5 consecutive days and killed 3 or 7 days after the last challenge to study the inflammatory and remodelling events, respectively. RESULTS Wild type mice challenged with ovalbumin exhibited an accumulation of eosinophils in the bronchoalveolar lavage (BAL) fluid, associated with a production of BAL cellular fibronectin. Histological analysis also revealed an antigen-specific increase in epithelial and alveolar cell proliferation together with an increase in mucus producing epithelial cells. Eosinophilic infiltration and the associated lung remodelling were totally abrogated in IL-5-deficient mice. In wild type mice, treated intranasally with 1 microg of murine IL-5 for 5 consecutive days, no BAL eosinophilia and structural changes of the lungs could be observed. CONCLUSION Our results demonstrate that eosinophil accumulation, but not IL-5 alone, plays a central role in the initial stages of the lung remodelling process and suggests that therapies directed at inhibiting eosinophilic inflammation may be beneficial in treating chronic asthma.
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Bachmann MF, Gallimore A, Jones E, Ecabert B, Acha-Orbea H, Kopf M. Normal pathogen-specific immune responses mounted by CTLA-4-deficient T cells: a paradigm reconsidered. Eur J Immunol 2001; 31:450-8. [PMID: 11180109 DOI: 10.1002/1521-4141(200102)31:2<450::aid-immu450>3.0.co;2-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
CTLA-4 is a critical negative regulator of T cell responses and CTLA-4-deficient (CTLA-4(-/-)) mice die of a lymphproliferative disease. Nevertheless, RAG-2-deficient mice reconstituted with a mixture of CTLA-4(-/-) and normal (CTLA-4(+/+)) bone marrow survive in the absence of any signs of disease, although 50% of their T cells do not express CTLA-4. Using such mixed chimeras, we analyzed the role of CTLA-4 in specific T cell responses to lymphocytic choriomeningitis virus, Leishmania major and mouse mammary tumor virus, which cause acute, chronic and persistent infections, respectively. The populations of antigen-specific CTLA-4(-/-)CD4(+) and CTLA-4(-/-)CD8(+) T cells became activated, expanded and contracted indistinguishably from CTLA-4(+/+)CD4(+) and CTLA-4(+/+)CD8(+) T cells after infection with all three pathogens. Thus, CTLA-4 is not involved in the down-regulation of specific T cell responses and peripheral deletion in a T cell-autonomous fashion.
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Affiliation(s)
- M F Bachmann
- Basel Institute for Immunology, Basel, Switzerland.
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Patton EA, Brunet LR, La Flamme AC, Pedras-Vasconcelos J, Kopf M, Pearce EJ. Severe schistosomiasis in the absence of interleukin-4 (IL-4) is IL-12 independent. Infect Immun 2001; 69:589-92. [PMID: 11119559 PMCID: PMC97925 DOI: 10.1128/iai.69.1.589-592.2001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An interleukin-4 (IL-4)-dependent Th2 response allows wild-type mice to survive infection with the parasite Schistosoma mansoni. In the absence of IL-4, infected mice mount a Th1-like proinflammatory response, develop severe disease, and succumb. Neither the Th1 response nor morbidity is IL-12 dependent in this system.
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Affiliation(s)
- E A Patton
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York 14853, USA
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24
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Tanaka J, Ozaki H, Yasuda J, Horai R, Tagawa Y, Asano M, Saijo S, Imai M, Sekikawa K, Kopf M, Iwakura Y. Lipopolysaccharide-induced HIV-1 expression in transgenic mice is mediated by tumor necrosis factor-alpha and interleukin-1, but not by interferon-gamma nor interleukin-6. AIDS 2000; 14:1299-307. [PMID: 10930143 DOI: 10.1097/00002030-200007070-00001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND As serum HIV-1 load correlates well with the prognosis of the disease, it is suggested that the viral load is one of the major determinants of the disease progression of AIDS. Accordingly, HIV-1 activation mechanisms were extensively studied in vitro, and involvement of cytokines including tumor necrosis factor (TNF)-alpha, interleukin (IL)-1, IL-6 and interferon (IFN)-gamma has been suggested in this process. However, so far the roles of these cytokines in the HIV-1 expression in vivo have not been well elucidated because of the lack of appropriate animal disease models. OBJECTIVE To elucidate the roles of cytokines in HIV-1 activation in vivo. DESIGN AND METHODS Transgenic mice carrying a defective HIV-1 genome were used as a model for HIV-1 carriers. In order to examine the possible involvement of cytokines in HIV-1 expression, TNF-alpha-, IL-1-, IL-6- and IFN-gamma-deficient HIV-1 transgenic mice, were produced and HIV-1 expression was analyzed after activation with bacterial lipopolysaccharides (LPS). RESULTS HIV-1 expression in the transgenic mouse spleen was activated 10- to 20-fold by LPS, and the serum p24 Gag protein levels reached 400 pg/ml, which is nearly equal to the levels that occur in AIDS patients. However, this augmentation was suppressed by 60% in TNF-alpha-deficient mice and by 40% in IL-1alpha/beta-deficient mice. In contrast, no suppression was observed in either IL-6-, IFN-gamma-, IL-1alpha, or IL-1beta-deficient mice. CONCLUSIONS Results suggest that TNF-alpha and IL-1 play important roles in HIV-1 gene activation and selective suppression of these cytokines could improve clinical prognosis and potentially slow progression of the disease.
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Affiliation(s)
- J Tanaka
- Center for Experimental Medicine, Institute of Medical Science, University of Tokyo, Japan
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Kopf M, Coyle AJ, Schmitz N, Barner M, Oxenius A, Gallimore A, Gutierrez-Ramos JC, Bachmann MF. Inducible costimulator protein (ICOS) controls T helper cell subset polarization after virus and parasite infection. J Exp Med 2000; 192:53-61. [PMID: 10880526 PMCID: PMC1887704 DOI: 10.1084/jem.192.1.53] [Citation(s) in RCA: 168] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
It has been shown that certain pathogens can trigger efficient T cell responses in the absence of CD28, a key costimulatory receptor expressed on resting T cells. Inducible costimulator protein (ICOS) is an inducible costimulator structurally and functionally related to CD28. Here, we show that in the absence of CD28 both T helper cell type 1 (Th1) and Th2 responses were impaired but not abrogated after infection with lymphocytic choriomeningitis virus (LCMV), vesicular stomatitis virus (VSV), and the nematode Nippostrongylus brasiliensis. Inhibition of ICOS in CD28-deficient mice further reduced Th1/Th2 polarization. Blocking of ICOS alone had a limited but significant capacity to downregulate Th subset development. In contrast, cytotoxic T lymphocyte (CTL) responses, which are regulated to a minor and major extent by CD28 after LCMV and VSV infection, respectively, remained unaffected by blocking ICOS. Together, our results demonstrate that ICOS regulates both CD28-dependent and CD28-independent CD4(+) subset (Th1 and Th2) responses but not CTL responses in vivo.
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Affiliation(s)
- M Kopf
- Basel Institute for Immunology, 4005 Basel, Switzerland.
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26
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Abstract
Although the amount of antigen and the strength of T cell stimulation have been suggested to regulate Th1 vs. Th2 polarization, it remains unclear how the antigen dose and the strength of signal is detected by the T cell and translated into differential cytokine production. Using co-cultures of dendritic cells (DC) and ovalbumin (OVA)-specific CD4+ T cells obtained from RAG-2)(-/-) DO11.10 mice, we show here that high-dose antigen induced Th1 development by up-regulation of CD40 ligand (CD40L), whereas low-dose antigen stimulation failed to induce CD40L and promoted Th2 development. CD40-CD40L interaction was essential for IL-12 production by DC. In the absence, de novo IL-4 production by T cells and autocrine Th2 development was induced. Furthermore, our results demonstrate that LFA-1/ ICAM interaction promotes Th1 differentiation by lowering the antigen dose required for CD40L up-regulation. Thus, we propose that (1) peptide-MHC density and (2) accessory molecules such as LFA-1 determine T helper polarization by regulation of CD40L.
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Affiliation(s)
- C Ruedl
- Basel Institute for Immunology, Switzerland
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27
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Camoglio L, te Velde AA, de Boer A, ten Kate FJ, Kopf M, van Deventer SJ. Hapten-induced colitis associated with maintained Th1 and inflammatory responses in IFN-gamma receptor-deficient mice. Eur J Immunol 2000. [PMID: 10820397 DOI: 10.1002/(sici)1521-4141(200005)30:5<1486::aid-immu1486>3.0.co;2-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
IFN-gamma is a potent pro-inflammatory cytokine thought to be involved in the pathogenesis of Crohn's disease. To further define the role of IFN-gamma in intestinal inflammation, we studied the effects of intra-colonic 2,4,6-trinitrobenzene sulfonic acid (TNBS) instillation in mice with a functionally inactivated IFN-gamma receptor 1 (IFN-gammaR1(- / -)). Our results indicate that IFN-gamma is not necessary for the induction of hapten-induced colitis: after TNBS administration both wild-type and IFN-gammaR1(- / -) mice lost body weight, and the histological features of TNBS-induced colitis were comparable. Colons of IFN-gammaR1(- / -) mice contained a greater number of cells, represented by macrophages and CD4(+) T cells; caudal lymph node cells produced more IFN-gamma and TNF-alpha upon stimulation in vitro. Moreover, IL-18 and IL-12 p40 RNA levels were comparably up-regulated after TNBS treatment in IFN-gammaR1(- / -) wild-type mice. These findings demonstrate that IFN-gamma is dispensable for the development of TNBS-induced colitis. Importantly, the production of Th1 cytokines (e. g. IFN-gamma and TNF-alpha) by caudal lymph node T lymphocytes was enhanced rather than decreased in IFNgammaR1(- / -) mice with no evidence for default Th2 development.
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Affiliation(s)
- L Camoglio
- Laboratory of Experimental Internal Medicine, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
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Camoglio L, te Velde AA, de Boer A, ten Kate FJ, Kopf M, van Deventer SJ. Hapten-induced colitis associated with maintained Th1 and inflammatory responses in IFN-gamma receptor-deficient mice. Eur J Immunol 2000; 30:1486-95. [PMID: 10820397 DOI: 10.1002/(sici)1521-4141(200005)30:5<1486::aid-immu1486>3.0.co;2-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
IFN-gamma is a potent pro-inflammatory cytokine thought to be involved in the pathogenesis of Crohn's disease. To further define the role of IFN-gamma in intestinal inflammation, we studied the effects of intra-colonic 2,4,6-trinitrobenzene sulfonic acid (TNBS) instillation in mice with a functionally inactivated IFN-gamma receptor 1 (IFN-gammaR1(- / -)). Our results indicate that IFN-gamma is not necessary for the induction of hapten-induced colitis: after TNBS administration both wild-type and IFN-gammaR1(- / -) mice lost body weight, and the histological features of TNBS-induced colitis were comparable. Colons of IFN-gammaR1(- / -) mice contained a greater number of cells, represented by macrophages and CD4(+) T cells; caudal lymph node cells produced more IFN-gamma and TNF-alpha upon stimulation in vitro. Moreover, IL-18 and IL-12 p40 RNA levels were comparably up-regulated after TNBS treatment in IFN-gammaR1(- / -) wild-type mice. These findings demonstrate that IFN-gamma is dispensable for the development of TNBS-induced colitis. Importantly, the production of Th1 cytokines (e. g. IFN-gamma and TNF-alpha) by caudal lymph node T lymphocytes was enhanced rather than decreased in IFNgammaR1(- / -) mice with no evidence for default Th2 development.
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Affiliation(s)
- L Camoglio
- Laboratory of Experimental Internal Medicine, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
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29
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van Den Broek M, Bachmann MF, Köhler G, Barner M, Escher R, Zinkernagel R, Kopf M. IL-4 and IL-10 antagonize IL-12-mediated protection against acute vaccinia virus infection with a limited role of IFN-gamma and nitric oxide synthetase 2. J Immunol 2000; 164:371-8. [PMID: 10605032 DOI: 10.4049/jimmunol.164.1.371] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Resistance or susceptibility to most infectious diseases is strongly determined by the balance of type 1 vs type 2 cytokines produced during infection. However, for viruses, this scheme may be applicable only to infections with some cytopathic viruses, where IFN-gamma is considered as mandatory for host defense with little if any participation of type 2 responses. We studied the role of signature Th1 (IL-12, IFN-gamma) and Th2 (IL-4, IL-10) cytokines for immune responses against vaccinia virus (VV). IL-12-/- mice were far more susceptible than IFN-gamma-/- mice, and primary CTL responses against VV were absent in IL-12-/- mice but remained intact in IFN-gamma-/- mice. Both CD4+ and CD8+ T cells from IL-12-/- mice were unimpaired in IFN-gamma production, although CD4+ T cells showed elevated Th2 cytokine responses. Virus replication was impaired in IL-4-/- mice and, even more strikingly, in IL-10-/- mice, which both produced elevated levels of the proinflammatory cytokines IL-1alpha and IL-6. Thus, IL-4 produced by Th2 cells and IL-10 produced by Th2 cells and probably also by macrophages counteract efficient anti-viral host defense. Surprisingly, NO production, which is considered as a major type 1 effector pathway inhibited by type 2 cytokines, appears to play a limited role against VV, because NO sythetase 2-deficient mice did not show increased viral replication. Thus, our results identify a new role for IL-12 in defense beyond the induction of IFN-gamma and show that IL-4 and IL-10 modulate host protective responses to VV.
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30
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Del Sero G, Mencacci A, Cenci E, d'Ostiani CF, Montagnoli C, Bacci A, Mosci P, Kopf M, Romani L. Antifungal type 1 responses are upregulated in IL-10-deficient mice. Microbes Infect 1999; 1:1169-80. [PMID: 10580272 DOI: 10.1016/s1286-4579(99)00245-2] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
C57BL/6 mice are highly resistant to infections caused by Candida albicans and Aspergillus fumigatus. To elucidate the role of IL-10 produced by C57BL/6 mice during these infections, parameters of infection and immunity to it were evaluated in IL-10-deficient and wild-type mice with disseminated or gastrointestinal candidiasis or invasive pulmonary aspergillosis. Unlike parasitic protozoan infection, C. albicans or A. fumigatus infection did not induce significant acute toxicity in IL-10-deficient mice, who, instead, showed reduced fungal burden and fungal-associated inflammatory responses. The increased resistance to infections as compared to wild-type mice was associated with upregulation of innate and acquired antifungal Th1 responses, such as a dramatically higher production of IL-12, nitric oxide (NO) and TNF-alpha as well as IFN-gamma by CD4+ T cells. Pharmacological inhibition of NO production greatly reduced resistance to gastrointestinal candidiasis, thus pointing to the importance of IL-10-dependent NO regulation at mucosal sites in fungal infections. These results are reminiscent of those obtained in genetically susceptible mice, in which IL-10 administration increased, and IL-10 neutralization decreased, susceptibility to C. albicans and A. fumigatus infections. Collectively, these observations indicate that the absence of IL-10 augments innate and acquired antifungal immunity by upregulating type 1 cytokine responses. The resulting protective Th1 responses lead to a prompt reduction of fungal growth, thus preventing tissue destruction and lethal levels of proinflammatory cytokines.
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Affiliation(s)
- G Del Sero
- Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Italy
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31
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Kopf M, Ruedl C, Schmitz N, Gallimore A, Lefrang K, Ecabert B, Odermatt B, Bachmann MF. OX40-deficient mice are defective in Th cell proliferation but are competent in generating B cell and CTL Responses after virus infection. Immunity 1999; 11:699-708. [PMID: 10626892 DOI: 10.1016/s1074-7613(00)80144-2] [Citation(s) in RCA: 256] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OX40, a member of the TNF receptor superfamily, is expressed on activated T cells and implicated in stimulation of T cells and T-dependent humoral responses. We generated OX40-/- mice and found that the formation of extrafollicular plasma cells, germinal centers, and antibody responses was independent of OX40. After infection with LCMV and influenza virus, OX40-/- mice retain primary and memory cytotoxic T cell responses with normal expansion and decline of specific CTL. In contrast, CD4+ T cell proliferation and the number of IFN-gamma-producing CD4+ T cells were reduced in OX40-/- mice. Moreover, the number of CD4+ T cells infiltrating the lungs of influenza virus-infected OX40-/- mice was reduced. These results define a unique role of OX40 in the generation of optimal CD4+ T cell responses in vivo.
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MESH Headings
- Animals
- Antibodies, Viral/immunology
- B-Lymphocytes/immunology
- B-Lymphocytes/virology
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/virology
- Cell Division
- Cell Line
- Dogs
- Female
- Humans
- Influenza A virus/immunology
- Lymphocytic choriomeningitis virus/immunology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Receptors, OX40
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor/immunology
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/virology
- T-Lymphocytes, Helper-Inducer/immunology
- T-Lymphocytes, Helper-Inducer/virology
- Tumor Necrosis Factor Receptor Superfamily, Member 7/genetics
- Tumor Necrosis Factor Receptor Superfamily, Member 7/immunology
- Vesicular stomatitis Indiana virus/immunology
- Virus Diseases/immunology
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Affiliation(s)
- M Kopf
- Basel Institute for Immunology, Basel, Switzerland.
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32
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Cenci E, Mencacci A, Del Sero G, Bacci A, Montagnoli C, d'Ostiani CF, Mosci P, Bachmann M, Bistoni F, Kopf M, Romani L. Interleukin-4 causes susceptibility to invasive pulmonary aspergillosis through suppression of protective type I responses. J Infect Dis 1999; 180:1957-68. [PMID: 10558953 DOI: 10.1086/315142] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Aspergillus fumigatus, an opportunistic fungal pathogen, causes multiple allergic and nonallergic airway diseases. Invasive pulmonary aspergillosis (IPA) is a nonallergic, life-threatening disease of immunocompromised patients. In a murine model of IPA, interleukin (IL)-4-deficient (IL-4-/-) BALB/c mice were used to examine the role of IL-4 in lung pathology and immune responses. IL-4-/- mice were more resistant than wild-type mice to infection caused by multiple intranasal injections of viable A. fumigatus conidia. Resistance was associated with decreased lung inflammatory pathology, impaired T helper (Th)-2 responses (including lung eosinophilia), and an IL-12-dependent Th1 response. In contrast, development of host-detrimental antifungal Th2 cells occurred in IL-12-/- and interferon-gamma-/- mice and in IL-4-/- mice when subjected to IL-12 neutralization. These results demonstrate that IL-4 renders mice susceptible to infection with A. fumigatus by inhibition of protective Th1 responses. IL-4 appears to have a distinct role in the pathogenesis of allergic and nonallergic lung diseases caused by the fungus.
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Affiliation(s)
- E Cenci
- Microbiology Section, Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy
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33
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Abstract
It has been proposed that CD2, which is highly expressed on T cells, serves to enhance T cell-antigen presenting cell (APC) adhesion and costimulate T cell activation. Here we analyzed the role of CD2 using CD2-deficient mice crossed with transgenic mice expressing a T cell receptor specific for lymphocytic choriomeningitis virus (LCMV)-derived peptide p33. We found that absence of CD2 on T cells shifted the p33-specific dose-response curve in vitro by a factor of 3-10. In comparison, stimulation of T cells in the absence of lymphocyte function-associated antigen (LFA)-1-intercellular adhesion molecule (ICAM)-1 interaction shifted the dose-response curve by a factor of 10, whereas absence of both CD2-CD48 and LFA-1-ICAM-1 interactions shifted the response by a factor of approximately 100. This indicates that CD2 and LFA-1 facilitate T cell activation additively. T cell activation at low antigen density was blocked at its very first steps, as T cell APC conjugate formation, TCR triggering, and Ca(2+) fluxes were affected by the absence of CD2. In vivo, LCMV-specific, CD2-deficient T cells proliferated normally upon infection with live virus but responded in a reduced fashion upon cross-priming. Thus, CD2 sets quantitative thresholds and fine-tunes T cell activation both in vitro and in vivo.
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Affiliation(s)
- M F Bachmann
- Basel Institute for Immunology, CH 4005 Basel, Switzerland.
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34
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Abstract
Disruption of the IL-4 gene in two inbred mouse strains revealed a dual role of IL-4 in Staphylococcus aureus sepsis and arthritis depending on the host's genetic background. IL-4 was protective in 129SV mice, since 5 days after S. aureus inoculation IL-4(-/-) mice displayed 70% mortality as compared to survival of all 129SV wild-type counterparts. On the other hand, IL-4 was detrimental in C57BL/6 mice, since survival of IL-4(-/-) C57BL/6 mice was increased, as compared to wild-type controls, due to decreased staphylococcal growth. Altogether, our results show the dual role of IL-4 in S. aureus sepsis and arthritis, depending on the genetic background of the host.
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Affiliation(s)
- O Hultgren
- Department of Rheumatology University of Göteborg, Göteborg, Sweden.
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35
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Bachmann MF, Köhler G, Ecabert B, Mak TW, Kopf M. Cutting edge: lymphoproliferative disease in the absence of CTLA-4 is not T cell autonomous. J Immunol 1999; 163:1128-31. [PMID: 10415006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Mice deficient for the expression of CTLA-4 develop a lethal lymphoproliferative syndrome and multiorgan inflammation leading to death at about 4 wk of age. Here we show that RAG2-deficient mice reconstituted with CTLA-4-deficient bone marrow do not develop a lymphoproliferative syndrome despite lymphocyte infiltration mainly into pericardium and liver. Moreover, RAG2-deficient mice reconstituted with a mixture of normal and CTLA-4-deficient bone marrow remain healthy and do not develop any disease. Thus, the lethal disease observed in CTLA-4-deficient mice is not T cell autonomous and can be prevented by factors produced by normal T cells.
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36
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Abstract
Induction of cytotoxic T lymphocyte (CTL) responses against minor histocompatibility antigens is dependent upon the presence of T cell help and requires the interaction of CD40 on dendritic cells (DCs) with CD40 ligand on activated T helper cells (Th). This study demonstrates that CD40 is neither involved in Th-dependent nor Th-independent antiviral CTL responses. Moreover, the data show that DC maturation occurs in vivo after viral infection in the absence of CD40 and Th. This maturation did not require viral infection of DCs but was mediated by peptide-specific CD8(+) T cells. Surprisingly, naive CD8(+) T cells were able to trigger DC maturation within 24 h after activation in vivo and in vitro. Moreover, peptide-activated CD8(+) T cells were able to induce maturation in trans, as DCs that failed to present the relevant antigen in vivo also underwent maturation. Upon isolation, the in vivo-stimulated DCs were able to convert a classically Th-dependent CTL response (anti-HY) into a Th-independent response in vitro. Thus, antiviral CD8(+) T cells are sufficient for the maturation of DCs in the absence of CD40.
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Affiliation(s)
- C Ruedl
- Basel Institute for Immunology, CH-4005 Basel, Switzerland
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37
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Abstract
The important role of B cells in protection against secondary viral infections has been recognized for a long time. Recent evidence suggests that B cells are also critically involved in protective immune reactions classically attributed to T cells. Specifically, antibodies have been documented to protect from many primary viral and parasitic infections and to be indispensable for the control of latent viral infections. Current vaccine strategies should take into account this pivotal role of antibodies.
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Affiliation(s)
- M F Bachmann
- Basel Institute for Immunology Grenzacherstrasse 487, 4005 Basel, Switzerland.
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38
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Zhong J, Dietzel ID, Wahle P, Kopf M, Heumann R. Sensory impairments and delayed regeneration of sensory axons in interleukin-6-deficient mice. J Neurosci 1999; 19:4305-13. [PMID: 10341234 PMCID: PMC6782624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
Interleukin-6 (IL-6) is a multifunctional cytokine mediating inflammatory or immune reactions. Here we investigated the possible role of IL-6 in the intact or lesioned peripheral nervous system using adult IL-6 gene knockout (IL-6(-/-)) mice. Various sensory functions were tested by applying electrophysiological, morphological, biochemical, and behavioral methods. There was a 60% reduction of the compound action potential of the sensory branch of IL-6(-/-) mice as compared with the motor branch in the intact sciatic nerve. Cross sections of L5 DRG of IL-6(-/-) mice showed a shift in the relative size distribution of the neurons. The temperature sensitivity of IL-6(-/-) mice was also significantly reduced. After crush lesion of the sciatic nerve, its functional recovery was delayed in IL-6(-/-) mice as analyzed from a behavioral footprint assay. Measurements of compound action potentials 20 d after crush lesion showed that there was a very low level of recovery of the sensory but not of the motor branch of IL-6(-/-) mice. Similar results of sensory impairments were obtained with mice showing slow Wallerian degeneration (Wlds) and a delayed lesion-induced recruitment of macrophages. However, in contrast to WldS mice, in IL-6(-/-) mice we observed the characteristic lesion-induced invasion of macrophages and the upregulation of low-affinity neurotrophin receptor p75 (p75LNTR) mRNA levels identical to those of IL-6(+/+) mice. Thus, the mechanisms leading to the common sensory deficiencies were different between IL-6(-/-) and WldS mice. Altogether, the results suggest that interleukin-6 is essential to modulate sensory functions in vivo.
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Affiliation(s)
- J Zhong
- Lehrstuhl für Molekulare Neurobiochemie, Ruhr-Universität Bochum, 44780 Bochum Germany
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39
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Abstract
The present report describes novel in vitro assays to determine influenza virus titers and virus neutralizing antibody levels. For determination of viral titers, serial dilutions of influenza virus were incubated with MDCK-cells and cultured for 48 h under a methylcellulose overlay in 24 well plates. Cells were fixed, permeabilized and stained with a monoclonal antibody specific for hemagglutitin (HA) and a peroxidase labelled second stage antibody. The sensitivity of the assay was 100-1000 times greater than a conventional hemagglutination test using fresh chicken blood. For determination of influenza virus neutralizing activity, viral samples were incubated with serial dilutions of antibody and residual viral activity was assessed in 96 well plates by the same procedure as described above. This assay made it possible to distinguish between IgM and IgG antibody titers and was about 5-10 fold more sensitive than a classical hemagglutination inhibition assay using fresh chicken blood.
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40
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Bachmann MF, Gallimore A, Linkert S, Cerundolo V, Lanzavecchia A, Kopf M, Viola A. Developmental regulation of Lck targeting to the CD8 coreceptor controls signaling in naive and memory T cells. J Exp Med 1999; 189:1521-30. [PMID: 10330431 PMCID: PMC2193636 DOI: 10.1084/jem.189.10.1521] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
The question of whether enhanced memory T cell responses are simply due to an increased frequency of specific cells or also to an improved response at the single cell level is widely debated. In this study, we analyzed T cell receptor (TCR) transgenic memory T cells and bona fide memory T cells isolated from virally infected normal mice using the tetramer technology. We found that memory T cells are qualitatively different from naive T cells due to a developmentally regulated rearrangement of the topology of the signaling machinery. In naive cytotoxic T cells, only a few CD8 molecules are associated with Lck and the kinase is homogeneously distributed inside the cell. However, in vivo priming of naive T cells induces the targeting of Lck to the CD8 coreceptor in the cell membrane and the consequent organization of a more efficient TCR signaling machinery in effector and memory cells.
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Affiliation(s)
- M F Bachmann
- Basel Institute for Immunology, CH-4005 Basel, Switzerland
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41
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Abstract
In the present study, naive T cells were compared with in vivo generated effector and memory T cells expressing the same TCR specific for lymphocytic choriomeningitis virus. Upon restimulation in vitro, the same minimal concentrations of the full agonist peptide p33 and also of weak and partial agonist peptides were required for proliferation of naive, effector and memory T cells, indicating no difference in threshold of activation. However, activation kinetics were distinct. While effector cytotoxic T cells exhibited immediate ex vivo lytic effector function, naive and memory T cells required 12 h and more exposure to antigen to develop lytic activity. However, both effector and memory T cells contained IFN-gamma mRNA in vivo and required less than 3 h for secretion of cytokines upon restimulation in vitro. In contrast, naive T cells did not contain IFN-gamma mRNA and required more than 12 h for cytokine secretion. Our results show that memory T cells exhibit a unique phenotype in that they produce cytokines and commit to proliferation as rapidly as effector cells, whereas they resemble naive T cells in the time requirement for development of cytolytic function.
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42
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Abstract
In the present study, naive T cells were compared with in vivo generated effector and memory T cells expressing the same TCR specific for lymphocytic choriomeningitis virus. Upon restimulation in vitro, the same minimal concentrations of the full agonist peptide p33 and also of weak and partial agonist peptides were required for proliferation of naive, effector and memory T cells, indicating no difference in threshold of activation. However, activation kinetics were distinct. While effector cytotoxic T cells exhibited immediate ex vivo lytic effector function, naive and memory T cells required 12 h and more exposure to antigen to develop lytic activity. However, both effector and memory T cells contained IFN-gamma mRNA in vivo and required less than 3 h for secretion of cytokines upon restimulation in vitro. In contrast, naive T cells did not contain IFN-gamma mRNA and required more than 12 h for cytokine secretion. Our results show that memory T cells exhibit a unique phenotype in that they produce cytokines and commit to proliferation as rapidly as effector cells, whereas they resemble naive T cells in the time requirement for development of cytolytic function.
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MESH Headings
- Animals
- Base Sequence
- Cell Differentiation
- Cytokines/biosynthesis
- Cytotoxicity, Immunologic
- DNA Primers/genetics
- Immunologic Memory
- In Vitro Techniques
- Interferon-gamma/biosynthesis
- Interferon-gamma/genetics
- Interleukin-2/biosynthesis
- Interleukin-2/pharmacology
- Kinetics
- Lymphocyte Activation
- Lymphocytic choriomeningitis virus/immunology
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- T-Lymphocytes/immunology
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43
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Schröder B, Dück R, Kopf M. [Mechanical properties of metal vascular implants (stents)]. BIOMED ENG-BIOMED TE 1998; 43 Suppl:436-7. [PMID: 9859433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Affiliation(s)
- B Schröder
- Naturwissenschaftliches und Medizinisches Institut an der Universität Tübingen in Reutlingen
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44
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Kopf M, Herren S, Wiles MV, Pepys MB, Kosco-Vilbois MH. Interleukin 6 influences germinal center development and antibody production via a contribution of C3 complement component. J Exp Med 1998; 188:1895-906. [PMID: 9815267 PMCID: PMC2212418 DOI: 10.1084/jem.188.10.1895] [Citation(s) in RCA: 159] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Mice rendered deficient for interleukin (IL) 6 by gene targeting were evaluated for their response to T cell-dependent antigens. Antigen-specific immunoglobulin (Ig)M levels were unaffected whereas all IgG isotypes showed varying degrees of alteration. Germinal center reactions occurred but remained physically smaller in comparison to those in the wild-type mice. This concurred with the observations that molecules involved in initial signaling events leading to germinal center formation were not altered (e.g., B7.2, CD40 and tumor necrosis factor R1). T cell priming was not impaired nor was a gross imbalance of T helper cell (Th) 1 versus Th2 cytokines observed. However, B7.1 molecules, absent from wild-type counterparts, were detected on germinal center B cells isolated from the deficient mice suggesting a modification of costimulatory signaling. A second alteration involved impaired de novo synthesis of C3 both in serum and germinal center cells from IL-6-deficient mice. Indeed, C3 provided an essential stimulatory signal for wild-type germinal center cells as both monoclonal antibodies that interrupted C3-CD21 interactions and sheep anti-mouse C3 antibodies caused a significant decrease in antigen-specific antibody production. In addition, germinal center cells isolated from C3-deficient mice produced a similar defect in isotype production. Low density cells with dendritic morphology were the local source of IL-6 and not the germinal center lymphocytes. Adding IL-6 in vitro to IL-6-deficient germinal center cells stimulated cell cycle progression and increased levels of antibody production. These findings reveal that the germinal center produces and uses molecules of the innate immune system, evolutionarily pirating them in order to optimally generate high affinity antibody responses.
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Affiliation(s)
- M Kopf
- Basel Institute for Immunology, CH-4005 Basel, Switzerland
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45
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Murphy WJ, Welniak LA, Taub DD, Wiltrout RH, Taylor PA, Vallera DA, Kopf M, Young H, Longo DL, Blazar BR. Differential effects of the absence of interferon-gamma and IL-4 in acute graft-versus-host disease after allogeneic bone marrow transplantation in mice. J Clin Invest 1998; 102:1742-8. [PMID: 9802888 PMCID: PMC509122 DOI: 10.1172/jci3906] [Citation(s) in RCA: 183] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Graft-versus-host disease (GVHD), in which immunocompetent donor cells attack the host, remains a major cause of morbidity after allogeneic bone marrow transplantation (BMT). To understand the role of cytokines in the pathobiology of GVHD, we used cytokine knockout (KO) mice as a source of donor T cells. Two different MHC-disparate strain combinations were examined: BALB/c (H2(d)) donors into lethally irradiated C57BL/6 (H2(b)) recipients or C57BL/6 (H2(b)) donors into B10.BR (H2(k)) recipients. Donor cells were from mice in which either the interferon-gamma (IFN-gamma) or the IL-4 gene was selectively disrupted to understand the role of these cytokines in acute GVHD. In both strain combinations the same pattern was noted with regard to GVHD onset and morbidity. All mice exhibited the classic signs of acute GVHD: weight loss with skin, gut, and liver pathology resulting in morbidity and mortality. Surprisingly, donor cells obtained from mice lacking IFN-gamma gave rise to accelerated morbidity from GVHD when compared with cells from wild-type control donors. Similar results were obtained using normal donors when neutralizing antibodies to IFN-gamma were administered immediately after the BMT. These results suggest that IFN-gamma plays a role in protection from acute GVHD. In marked contrast, cells obtained from IL-4 KO mice resulted in protection from GVHD compared with control donors. Splenocytes from IFN KO mice stimulated with a mitogen proliferated to a significantly greater extent and produced more IL-2 compared with splenocytes obtained from IL-4 KO or control mice. Additionally, there was increased IL-2 production in the spleens of mice undergoing GVHD using IFN-gamma KO donors. These results therefore indicate, with regard to the TH1/ TH2 cytokine paradigm, the absence of a TH1-type cytokine can be deleterious in acute GVHD, whereas absence of a TH2 cytokine can be protective.
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Affiliation(s)
- W J Murphy
- SAIC-Frederick, Division of Basic Science, National Cancer Institute, Frederick Cancer Research and Development Center, Frederick, Maryland 21702, USA.
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46
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Cenci E, Mencacci A, Del Sero G, d'Ostiani CF, Mosci P, Bacci A, Montagnoli C, Kopf M, Romani L. IFN-gamma is required for IL-12 responsiveness in mice with Candida albicans infection. J Immunol 1998; 161:3543-50. [PMID: 9759875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
To elucidate the role of IFN-gamma in antifungal CD4+ Th-dependent immunity, 129/Sv/Ev mice deficient for IFN-gamma receptor (IFN-gammaR(-/-)) were assessed for susceptibility to gastrointestinal or systemic Candida albicans infection and for parameters of innate and adaptive T helper immunity. IFN-gammaR(-/-) mice failed to mount protective Th1-mediated acquired immunity upon mucosal immunization or in response to a live vaccine strain of the yeast. The impaired Th1-mediated resistance correlated with defective IL-12 responsiveness, but not IL-12 production, and occurred in the presence of an increased innate antifungal resistance. The development of nonprotective Th2 responses was observed in IFN-gammaR(-/-) mice upon mucosal infection and subsequent reinfection. However, under experimental conditions of Th2 cell activation, the occurrence of Th2 cell responses was similar in IFN-gammaR(-/-) and in IFN-gammaR(+/+) mice. These results indicate the complex immunoregulatory role of IFN-gamma in the induction of mucosal and nonmucosal anticandidal Th cell responses; IFN-gamma is not essential for the occurrence of Th2 responses but is required for development of IL-12-dependent protective Th1-dependent immunity.
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Affiliation(s)
- E Cenci
- Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Italy
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47
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Abstract
Eosinophilic inflammation of the airways is believed to play a central role in the pathogenesis of bronchial asthma. Inoculation of mice with the nematode Nippostrongylus brasiliensis induces pulmonary inflammation, characterized by a marked infiltration of eosinophils, subsequent to the migration of parasites through the lungs. Infection is associated with polarized Th2 responses in different strains of mice tested. Thus, this model may be useful to determine the relationship between established pulmonary eosinophilic inflammation, Th2 immune responses and airway changes in a nonallergic background. In the present study, we have used IL-5-deficient mice to evaluate the role of IL-5 in eosinophilic lung inflammation and airway hyperresponsiveness (AHR). In wild-type C57B/6 mice, infection with N. brasiliensis resulted in eosinophil accumulation, associated with extensive lung damage characterized by hemorrhage and alveolar wall destruction, and a strong AHR following methacholine treatment. In IL-5-deficient mice, eosinophil infiltration and the associated lung damage was abrogated. Nonetheless, AHR was unimpaired. Our results suggest that eosinophil accumulation plays a central role in lung damage but is not responsible for the induction of airway constriction following N. brasiliensis infection.
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Affiliation(s)
- A J Coyle
- Department of Biology, Millenium Pharmaceuticals, Cambridge, Boston, USA
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48
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Ohshima S, Saeki Y, Mima T, Sasai M, Nishioka K, Nomura S, Kopf M, Katada Y, Tanaka T, Suemura M, Kishimoto T. Interleukin 6 plays a key role in the development of antigen-induced arthritis. Proc Natl Acad Sci U S A 1998; 95:8222-6. [PMID: 9653168 PMCID: PMC20957 DOI: 10.1073/pnas.95.14.8222] [Citation(s) in RCA: 297] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
To investigate the direct role of interleukin (IL) 6 in the development of rheumatoid arthritis, IL-6-deficient (IL-6 -/-) mice were backcrossed for eight generations into C57BL/6 mice, a strain of mice with a genetic background of susceptibility for antigen-induced arthritis (AIA). Both histological and immunological comparisons were made between IL-6-deficient (IL-6 -/-) mice and wild-type (IL-6 +/+) littermates after the induction of AIA. Although all IL-6 +/+ mice developed severe arthritis, only mild arthritis was observed in IL-6 -/- mice. Safranin O staining demonstrated that articular cartilage was well preserved in IL-6 -/- mice, whereas it was destroyed completely in IL-6 +/+ mice. In addition, comparable mRNA expression for both IL-1beta and tumor necrosis factor alpha, but not for IL-6, was detected in the inflamed joints of IL-6 -/- mice, suggesting that IL-6 may play a more crucial role in cartilage destruction than either IL-1beta or tumor necrosis factor alpha. In immunological comparisons, both antigen-specific in vitro proliferative response in lymph node cells and in vivo antibody production were elicited in IL-6 -/- mice, but they were reduced to less than half of that found in IL-6 +/+ mice. Lymph node cells of IL-6 -/- mice produced many more Th2 cytokines than did IL-6 +/+ mice with either antigen-specific or nonspecific stimulation in in vitro culture. Taken together, these results indicate that IL-6 may play a key role in the development of AIA at the inductive as well as the effector phase, and the blockade of IL-6 is possibly beneficial in the treatment of rheumatoid arthritis.
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Affiliation(s)
- S Ohshima
- Department of Medicine III, Osaka University Medical School, Suita City, Osaka 565-0871, Japan
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49
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Abstract
Experimental autoimmune encephalomyelitis (EAE) is induced by immunization with myelin components including myelin oligodendrocyte glycoprotein (MOG). Myelin-specific Th1 cells enter the central nervous system (CNS) via binding of very late antigen 4 (VLA-4) to the endothelial vascular cell adhesion molecule 1 (VCAM-1). In the present study, mice with a homologous disruption of the gene encoding IL-6 are found to be resistant to MOG-induced EAE as evidenced by absence of clinical symptoms, minimal infiltration of CD3+ T cells and monocytes into the CNS and lack of demyelination. The failure to induce EAE in IL-6-/- mice is not due to the absence of priming, since lymphocytes of immunized IL-6-/- mice proliferate in response to MOG and produce pro-inflammatory cytokines including IL-2 and IFN-gamma. However, in MOG-immunized IL-6-/- mice, serum anti-MOG antibody titers were found to be drastically reduced. This observation is unlikely to be responsible for resistance to EAE, because B cell-deficient (microMT) mice proved to be fully susceptible to the disease. A striking difference between MOG-immunized wild-type (wt) and IL-6-/- mice was the expression of endothelial VCAM-1 and ICAM-1, which were dramatically up-regulated in the CNS in wt but not in IL-6-/- mice. Taking into account recent studies on the role of VCAM-1 in the entry of Th1 cells into the CNS, the absence of VCAM-1 on endothelial cells in IL-6-/- mice may explain their resistance to EAE.
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Affiliation(s)
- H P Eugster
- Department of Internal Medicine, University Hospital Zurich, Switzerland.
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50
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Barner M, Mohrs M, Brombacher F, Kopf M. Differences between IL-4R alpha-deficient and IL-4-deficient mice reveal a role for IL-13 in the regulation of Th2 responses. Curr Biol 1998; 8:669-72. [PMID: 9635196 DOI: 10.1016/s0960-9822(98)70256-8] [Citation(s) in RCA: 166] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Allergens and infections with parasitic helminths preferentially induced Th2 immune responses associated with elevated levels of serum immunoglobulin E (IgE) and expansion of eosinophils and mast cells. Interleukin-4 (IL-4) is a key cytokine in the differentiation of naive CD4+ T cells into Th2 cells, which produce a panel of cytokines including IL-4, IL-5, IL-6, IL-9, IL-10, and IL-13 [1] and have been shown to trigger recovery from gastrointestinal nematodes [2]. Nonetheless, mice deficient for IL-4 have been shown to develop residual Th2 responses [3-5] and can expel the nematode Nippostrongylus brasiliensis [6], suggesting that there is a functional equivalent of IL-4 in these processes. IL-13 is a cytokine that shares some, but not all, biological activities with IL-4 [7,8]. There is now compelling evidence that IL-4 and IL-13 share receptor components, including IL-4R alpha and IL-13R alpha 1 [9]. In order to dissect the roles of IL-4 and IL-13 in the regulation of Th2 cells and in the response to nematode infections, we looked for differences between mice deficient for either the IL-4 gene or the IL-4R alpha gene. Unlike IL-4, IL-4R alpha was required for control of N. brasiliensis, and Th2 development during infection--as characterized by cytokine production, GATA-3 and surface CD30 expression--was more severely affected in IL-4R alpha-/- mice than in IL-4-/- mice. Injection of recombinant IL-13 induced worm expulsion in otherwise incompetent RAG2-/- mice. Our results suggest that IL-13 regulates Th2 responses to nematode infection and requires IL-4R alpha.
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Affiliation(s)
- M Barner
- Basel Institute for Immunology, Switzerland
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