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Steiner, Håkan
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Publikasjoner (10 av 13) Visa alla publikasjoner
Lindberg, B. G., Oldenvi, S. & Steiner, H. (2014). Medium from gamma-irradiated Escherichia coli bacteria stimulates a unique immune response in Drosophila cells. Developmental and Comparative Immunology, 46(2), 392-400
Åpne denne publikasjonen i ny fane eller vindu >>Medium from gamma-irradiated Escherichia coli bacteria stimulates a unique immune response in Drosophila cells
2014 (engelsk)Inngår i: Developmental and Comparative Immunology, ISSN 0145-305X, E-ISSN 1879-0089, Vol. 46, nr 2, s. 392-400Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

It is well known that gamma-irradiated, non-dividing bacteria can elicit potent immune responses in mammals. Compared to traditional heat or chemical inactivation of microbes, gamma -irradiation likely preserves metabolic activity and antigenic features to a larger extent. We have previously shown that antimicrobial peptides are induced in Drosophila by peptidoglycan fragments secreted into the medium of exponentially growing bacterial cultures. In this study, we gamma-irradiated Escherichia coil cells at a dose that halted cell division. The temporal synthesis and release of peptidoglycan fragments were followed as well as the potential of bacterial supernatants to induce immune responses in Drosophila S2 cells. We demonstrate that peptidoglycan synthesis continues for several days post irradiation and that monomeric peptidoglycan is shed into the medium. Whole transcriptome analysis revealed a strong immune response against the bacterial medium. The response to medium taken directly post irradiation shows a large overlap to that of peptidoglycan. Medium from prolonged bacterial incubation does, however, stimulate a selective set of immune genes. A shift towards a stress response was instead observed with a striking induction of several heat shock proteins. Our findings suggest that gamma-irradiated bacteria release elicitors that stimulate a novel response in Drosophila.

Emneord
Peptidoglycan, S2 cells, Antimicrobial peptides, Heat shock proteins
HSV kategori
Identifikatorer
urn:nbn:se:su:diva-107084 (URN)10.1016/j.dci.2014.05.018 (DOI)000340216600030 ()
Merknad

AuthorCount:3;

Tilgjengelig fra: 2014-09-07 Laget: 2014-09-03 Sist oppdatert: 2022-02-23bibliografisk kontrollert
Karlsson, J., Oldenvi, S., Fahlander, C., Daenthanasanmak, A. & Steiner, H. (2012). Growing bacteria shed elicitors of Drosophila humoral immunity.. Journal of innate immunity, 4(1), 111-116
Åpne denne publikasjonen i ny fane eller vindu >>Growing bacteria shed elicitors of Drosophila humoral immunity.
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2012 (engelsk)Inngår i: Journal of innate immunity, ISSN 1662-8128, Vol. 4, nr 1, s. 111-116Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

It has been much debated how the Drosophila immune system can recognize bacterial peptidoglycan that is often hidden. We show that bacteria separated from Drosophila S2 cells by a semipermeable membrane can upregulate the Imd pathway. Supernatants from exponentially growing but not from stationary-phase bacterial cultures induce antimicrobial peptides. It is also made likely that the shed elicitors are of peptidoglycan nature.

Emneord
Innate; Insect; Peptidoglycan
HSV kategori
Identifikatorer
urn:nbn:se:su:diva-70071 (URN)10.1159/000329224 (DOI)000299225900012 ()21829001 (PubMedID)
Merknad
5Tilgjengelig fra: 2012-01-17 Laget: 2012-01-17 Sist oppdatert: 2022-02-24bibliografisk kontrollert
Zaidman-Remy, A., Poidevin, M., Herve, M., Welchman, D. P., Paredes, J. C., Fahlander, C., . . . Lemaitre, B. (2011). Drosophila Immunity: Analysis of PGRP-SB1 Expression, Enzymatic Activity and Function. PLOS ONE, 6(2), e17231
Åpne denne publikasjonen i ny fane eller vindu >>Drosophila Immunity: Analysis of PGRP-SB1 Expression, Enzymatic Activity and Function
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2011 (engelsk)Inngår i: PLOS ONE, E-ISSN 1932-6203, Vol. 6, nr 2, s. e17231-Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Peptidoglycan is an essential and specific component of the bacterial cell wall and therefore is an ideal recognition signature for the immune system. Peptidoglycan recognition proteins (PGRPs) are conserved from insects to mammals and able to bind PGN (non-catalytic PGRPs) and, in some cases, to efficiently degrade it (catalytic PGRPs). In Drosophila, several non-catalytic PGRPs function as selective peptidoglycan receptors upstream of the Toll and Imd pathways, the two major signalling cascades regulating the systemic production of antimicrobial peptides. Recognition PGRPs specifically activate the Toll pathway in response to Lys-type peptidoglycan found in most Gram-positive bacteria and the Imd pathway in response to DAP-type peptidoglycan encountered in Gram-positive bacilli-type bacteria and in Gram-negative bacteria. Catalytic PGRPs on the other hand can potentially reduce the level of immune activation by scavenging peptidoglycan. In accordance with this, PGRP-LB and PGRP-SC1A/B/2 have been shown to act as negative regulators of the Imd pathway. In this study, we report a biochemical and genetic analysis of PGRP-SB1, a catalytic PGRP. Our data show that PGRP-SB1 is abundantly secreted into the hemolymph following Imd pathway activation in the fat body, and exhibits an enzymatic activity towards DAP-type polymeric peptidoglycan. We have generated a PGRP-SB1/2 null mutant by homologous recombination, but its thorough phenotypic analysis did not reveal any immune function, suggesting a subtle role or redundancy of PGRP-SB1/2 with other molecules. Possible immune functions of PGRP-SB1 are discussed.

HSV kategori
Identifikatorer
urn:nbn:se:su:diva-67510 (URN)10.1371/journal.pone.0017231 (DOI)000287482800036 ()
Merknad
authorCount :9Tilgjengelig fra: 2011-12-29 Laget: 2011-12-28 Sist oppdatert: 2022-02-24bibliografisk kontrollert
Persson, C., Oldenvi, S. & Steiner, H. (2007). Peptidoglycan recognition protein LF, A negative regulator of Drosophila immunity.. Insect Biochem Mol Biol, 37(12), 1309-16
Åpne denne publikasjonen i ny fane eller vindu >>Peptidoglycan recognition protein LF, A negative regulator of Drosophila immunity.
2007 (engelsk)Inngår i: Insect Biochem Mol Biol, ISSN 0965-1748, Vol. 37, nr 12, s. 1309-16Artikkel i tidsskrift (Fagfellevurdert) Published
Identifikatorer
urn:nbn:se:su:diva-20026 (URN)000251401800007 ()17967349 (PubMedID)
Tilgjengelig fra: 2007-11-21 Laget: 2007-11-21 Sist oppdatert: 2022-02-25bibliografisk kontrollert
Coteur, G., Mellroth, P., De Lefortery, C., Gillan, D., Dubois, P., Communi, D. & Steiner, H. (2007). Peptidoglycan recognition proteins with amidase activity in early deuterostomes (Echinodermata).. Dev Comp Immunol, 31(8), 790-804
Åpne denne publikasjonen i ny fane eller vindu >>Peptidoglycan recognition proteins with amidase activity in early deuterostomes (Echinodermata).
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2007 (engelsk)Inngår i: Dev Comp Immunol, ISSN 0145-305X, Vol. 31, nr 8, s. 790-804Artikkel i tidsskrift (Fagfellevurdert) Published
Emneord
Amidohydrolases/chemistry/*genetics/metabolism, Amino Acid Sequence, Animals, Asterias/*enzymology/genetics/*immunology, Base Sequence, Carrier Proteins/chemistry/*genetics/*immunology, Cloning; Molecular, Immunity; Natural, Micrococcus luteus, Molecular Sequence Data, Peptidoglycan/metabolism, Phagocytosis, Protein Binding, Reactive Oxygen Species/metabolism, Sequence Homology; Amino Acid
Identifikatorer
urn:nbn:se:su:diva-20024 (URN)000247120200004 ()17240448 (PubMedID)
Tilgjengelig fra: 2008-01-14 Laget: 2008-01-14 Sist oppdatert: 2022-02-25bibliografisk kontrollert
Mellroth, P. & Steiner, H. (2006). PGRP-SB1: an N-acetylmuramoyl L-alanine amidase with antibacterial activity.. Biochem Biophys Res Commun, 350(4), 994-9
Åpne denne publikasjonen i ny fane eller vindu >>PGRP-SB1: an N-acetylmuramoyl L-alanine amidase with antibacterial activity.
2006 (engelsk)Inngår i: Biochem Biophys Res Commun, ISSN 0006-291X, Vol. 350, nr 4, s. 994-9Artikkel i tidsskrift (Fagfellevurdert) Published
Emneord
Anti-Bacterial Agents/administration & dosage, Bacillus megaterium/*cytology/*drug effects, Carrier Proteins/*administration & dosage, Cell Survival/drug effects, Dose-Response Relationship; Drug, Drosophila Proteins/*administration & dosage
Identifikatorer
urn:nbn:se:su:diva-20027 (URN)17046713 (PubMedID)
Tilgjengelig fra: 2007-11-21 Laget: 2007-11-21 Sist oppdatert: 2022-02-25bibliografisk kontrollert
Mellroth, P., Karlsson, J., Håkansson, J., Schultz, N., Goldman, W. E. & Steiner, H. (2005). Ligand-induced dimerization of Drosophila peptidoglycan recognition proteins in vitro. Proceedings of the National Academy of Sciences of the United States of America, 102(18), 6455-6460
Åpne denne publikasjonen i ny fane eller vindu >>Ligand-induced dimerization of Drosophila peptidoglycan recognition proteins in vitro
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2005 (engelsk)Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 102, nr 18, s. 6455-6460Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Drosophila knockout mutants have placed peptidoglycan recognition proteins (PGRPs) in the two major pathways controlling immune gene expression. We now examine PGRP affinities for peptidoglycan. PGRP-SA and PGRP-LCx are bona fide pattern recognition receptors, and PGRP-SA, the peptidoglycan receptor of the Toll/Dif pathway, has selective affinity for different peptidoglycans. PGRP-LCx, the default peptidoglycan receptor of the Imd/Relish pathway, has strong affinity for all polymeric peptidoglycans tested and for monomeric peptidoglycan. PGRP-LCa does not have affinity for polymeric or monomeric peptidoglycan. Instead, PGRP-LCa can form heterodimers with LCx when the latter is bound to monomeric peptidoglycan. Hence, PGRP-LCa can be said to function as an adaptor, thus adding a new function to a member of the PGRP family.

Identifikatorer
urn:nbn:se:su:diva-20028 (URN)10.1073/pnas.0407559102 (DOI)15843462 (PubMedID)
Tilgjengelig fra: 2007-11-21 Laget: 2007-11-21 Sist oppdatert: 2022-02-25bibliografisk kontrollert
Kaneko, T., Goldman, W. E., Mellroth, P., Steiner, H., Fukase, K., Kusumoto, S., . . . Silverman, N. (2004). Monomeric and polymeric gram-negative peptidoglycan but not purified LPS stimulate the Drosophila IMD pathway.. Immunity, 20(5), 637-49
Åpne denne publikasjonen i ny fane eller vindu >>Monomeric and polymeric gram-negative peptidoglycan but not purified LPS stimulate the Drosophila IMD pathway.
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2004 (engelsk)Inngår i: Immunity, ISSN 1074-7613, Vol. 20, nr 5, s. 637-49Artikkel i tidsskrift (Fagfellevurdert) Published
Emneord
Animals, Blotting; Northern, Bombyx/immunology, Carrier Proteins/immunology, Drosophila/*immunology, Drosophila Proteins/*immunology, Gram-Negative Bacteria/chemistry/immunology, Lipid A/immunology, Lipopolysaccharides/*immunology, Peptidoglycan/chemistry/*immunology, Polymerase Chain Reaction, Protein Isoforms/immunology, Signal Transduction/*immunology
Identifikatorer
urn:nbn:se:su:diva-20029 (URN)15142531 (PubMedID)
Tilgjengelig fra: 2007-11-21 Laget: 2007-11-21 Sist oppdatert: 2022-02-25bibliografisk kontrollert
Steiner, H. (2004). Peptidoglycan recognition proteins: on and off switches for innate immunity.. Immunol Rev, 198, 83-96
Åpne denne publikasjonen i ny fane eller vindu >>Peptidoglycan recognition proteins: on and off switches for innate immunity.
2004 (engelsk)Inngår i: Immunol Rev, ISSN 0105-2896, Vol. 198, s. 83-96Artikkel i tidsskrift (Fagfellevurdert) Published
Emneord
Amino Acid Sequence, Animals, Carrier Proteins/chemistry/*immunology/physiology, Drosophila/genetics/*immunology, Drosophila Proteins/metabolism, Hemocytes/immunology, Humans, Immunity; Natural, Mice, Models; Molecular, Molecular Sequence Data, Molecular Structure, Receptors; Cell Surface/metabolism, Signal Transduction, Toll-Like Receptors
Identifikatorer
urn:nbn:se:su:diva-20034 (URN)15199956 (PubMedID)
Tilgjengelig fra: 2007-11-21 Laget: 2007-11-21 Sist oppdatert: 2022-02-25bibliografisk kontrollert
Gelius, E., Persson, C., Karlsson, J. & Steiner, H. (2003). A mammalian peptidoglycan recognition protein with N-acetylmuramoyl-L-alanine amidase activity. Biochemical and Biophysical Research Communications - BBRC, 306(4), 988-994
Åpne denne publikasjonen i ny fane eller vindu >>A mammalian peptidoglycan recognition protein with N-acetylmuramoyl-L-alanine amidase activity
2003 (engelsk)Inngår i: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 306, nr 4, s. 988-994Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The family of peptidoglycan recognition proteins (PGRPs) is conserved from insects to mammals. Recently, Drosophila PGRP-SC1B was demonstrated to be an N-acetylmuramoyl- -alanine amidase (NAMLAA), an enzyme that cleaves the lactylamide bond between muramic acid and the peptide chain in peptidoglycan (PGN). We now show an M.mPGRP-L mRNA to be expressed in the liver. The recombinant M.mPGRP-L protein has NAMLAA activity and degrades PGN from both Escherichia coli and Staphylococcus aureus; however, the Gram-positive PGN was a better substrate after lysozyme treatment. The activity of M.mPGRP-L was further analysed using Bordetella pertussis tracheal toxin as a substrate. Cleavage products were separated on HPLC and identified using mass spectrometry. From these results we conclude that M.mPGRP-L has activity and other properties identifying it as the NAMLAA protein present in mammalian sera.

Identifikatorer
urn:nbn:se:su:diva-20035 (URN)10.1016/S0006-291X(03)01096-9 (DOI)12821140 (PubMedID)
Tilgjengelig fra: 2007-11-21 Laget: 2007-11-21 Sist oppdatert: 2022-02-25bibliografisk kontrollert
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