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Bi K, Du J, Chen J, Wang H, Zhang K, Wang Y, Hou L, Meng Q. Screening and functional analysis of three Spiroplasma eriocheiris glycosylated protein interactions with Macrobrachium nipponense C-type lectins. FISH & SHELLFISH IMMUNOLOGY 2023; 138:108810. [PMID: 37169109 DOI: 10.1016/j.fsi.2023.108810] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/05/2023] [Accepted: 05/08/2023] [Indexed: 05/13/2023]
Abstract
N-glycosylation, one of the main protein posttranslational modifications (PTMs), plays an important role in the pathogenic process of pathogens through binding and invasion of host cells or regulating the internal environment of host cells to benefit their survival. However, N-glycosylation has remained mostly unexplored in Spiroplasma eriocheiris, a novel type of pathogen which has serious adverse effects on aquaculture. In most cases, N-glycoproteins can be detected and analyzed by lectins dependent on sugar recognition domains. In this study, three Macrobrachium nipponense C-type lectins, namely, MnCTLDcp1, MnCTLDcp2 and MnCTLDcp3, were used to screen S. eriocheiris glycosylated proteins. First, qRT-PCR results showed that the expression levels of the three kinds of lectins were all significantly up-regulated in prawn hearts when the host was against S. eriocheiris infection. A bacterial binding assay showed that purified recombinant MnCTLDcp1, MnCTLDcp2 and MnCTLDcp3 could directly bind to S. eriocheiris in vitro. Second, three S. eriocheiris glycosylated proteins, ATP synthase subunit beta (ATP beta), molecular chaperone Dnak (Dnak) and fructose bisphosphate aldolase (FBPA), were screened and identified using the three kinds of full-length C-type lectins. Far-Western blot and coimmunoprecipitation (CO-IP) further demonstrated that there were interactions between the three lectins with ATP beta, Dnak and FBPA. Furthermore, antibody neutralization assay results showed that pretreatment of S. eriocheiris with ATP beta, Dnak and FBPA antibodies could significantly block this pathogen infection. All the above studies showed that the glycosylated protein played a vital role in the process of S. eriocheiris infection.
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Affiliation(s)
- Keran Bi
- Animal Husbandry and Veterinary College, Jiangsu Vocational College of Agriculture and Forestry, Jurong, Jiangsu, 212400, China
| | - Jie Du
- Animal Husbandry and Veterinary College, Jiangsu Vocational College of Agriculture and Forestry, Jurong, Jiangsu, 212400, China
| | - Jun Chen
- Animal Husbandry and Veterinary College, Jiangsu Vocational College of Agriculture and Forestry, Jurong, Jiangsu, 212400, China
| | - Huicong Wang
- Animal Husbandry and Veterinary College, Jiangsu Vocational College of Agriculture and Forestry, Jurong, Jiangsu, 212400, China
| | - Kun Zhang
- Animal Husbandry and Veterinary College, Jiangsu Vocational College of Agriculture and Forestry, Jurong, Jiangsu, 212400, China
| | - Yuheng Wang
- Animal Husbandry and Veterinary College, Jiangsu Vocational College of Agriculture and Forestry, Jurong, Jiangsu, 212400, China
| | - Libo Hou
- Engineering Lab of Henan Province for Aquatic Animal Disease Control, College of Fisheries, Henan Normal University, Xinxiang, 453007, China.
| | - Qingguo Meng
- Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Marine Science and Engineering, Nanjing Normal University, 2 Xuelin Road, Nanjing, 210023, China.
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Glycosylation-dependent galectin-receptor interactions promote Chlamydia trachomatis infection. Proc Natl Acad Sci U S A 2018; 115:E6000-E6009. [PMID: 29891717 DOI: 10.1073/pnas.1802188115] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Chlamydia trachomatis (Ct) constitutes the most prevalent sexually transmitted bacterium worldwide. Chlamydial infections can lead to severe clinical sequelae including pelvic inflammatory disease, ectopic pregnancy, and tubal infertility. As an obligate intracellular pathogen, Ct has evolved multiple strategies to promote adhesion and invasion of host cells, including those involving both bacterial and host glycans. Here, we show that galectin-1 (Gal1), an endogenous lectin widely expressed in female and male genital tracts, promotes Ct infection. Through glycosylation-dependent mechanisms involving recognition of bacterial glycoproteins and N-glycosylated host cell receptors, Gal1 enhanced Ct attachment to cervical epithelial cells. Exposure to Gal1, mainly in its dimeric form, facilitated bacterial entry and increased the number of infected cells by favoring Ct-Ct and Ct-host cell interactions. These effects were substantiated in vivo in mice lacking Gal1 or complex β1-6-branched N-glycans. Thus, disrupting Gal1-N-glycan interactions may limit the severity of chlamydial infection by inhibiting bacterial invasion of host cells.
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Shima K, Coopmeiners J, Graspeuntner S, Dalhoff K, Rupp J. Impact of micro-environmental changes on respiratory tract infections with intracellular bacteria. FEBS Lett 2016; 590:3887-3904. [PMID: 27509029 DOI: 10.1002/1873-3468.12353] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 07/29/2016] [Accepted: 08/05/2016] [Indexed: 12/26/2022]
Abstract
Community-acquired pneumonia is caused by intra- and extracellular bacteria, with some of these bacteria also being linked to the pathogenesis of chronic lung diseases, including asthma and chronic obstructive pulmonary disease. Chlamydia pneumoniae is an obligate intracellular pathogen that is highly sensitive to micro-environmental conditions controlling both pathogen growth and host immune responses. The availability of nutrients, as well as changes in oxygen, pH and interferon-γ levels, have been shown to directly influence the chlamydial life cycle and clearance. Although the lung has been traditionally regarded as a sterile environment, sequencing approaches have enabled the identification of a large number of bacteria in healthy and diseased lungs. The influence of the lung microbiota on respiratory infections has not been extensively studied so far and data on chlamydial infections are currently unavailable. In the present study, we speculate on how lung microbiota might interfere with acute and chronic infections by focusing exemplarily on the obligate intracellular C. pneumoniae. Furthermore, we consider changes in the gut microbiota as an additional player in the control of lung infections, especially in view the increasing evidence suggesting the involvement of the gut microbiota in various immunological processes throughout the human body.
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Affiliation(s)
- Kensuke Shima
- Department of Infectious Diseases and Microbiology, University of Lübeck, Germany
| | - Jonas Coopmeiners
- Department of Infectious Diseases and Microbiology, University of Lübeck, Germany
| | - Simon Graspeuntner
- Department of Infectious Diseases and Microbiology, University of Lübeck, Germany
| | - Klaus Dalhoff
- Medical Clinic III, University-Hospital Schleswig-Holstein/Campus Lübeck, Germany
| | - Jan Rupp
- Department of Infectious Diseases and Microbiology, University of Lübeck, Germany
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Collaborative action of Toll-like and NOD-like receptors as modulators of the inflammatory response to pathogenic bacteria. Mediators Inflamm 2014; 2014:432785. [PMID: 25525300 PMCID: PMC4267164 DOI: 10.1155/2014/432785] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 06/11/2014] [Accepted: 06/27/2014] [Indexed: 01/20/2023] Open
Abstract
Early sensing of pathogenic bacteria by the host immune system is important to develop effective mechanisms to kill the invader. Microbial recognition, activation of signaling pathways, and effector mechanisms are sequential events that must be highly controlled to successfully eliminate the pathogen. Host recognizes pathogens through pattern-recognition receptors (PRRs) that sense pathogen-associated molecular patterns (PAMPs). Some of these PRRs include Toll-like receptors (TLRs), nucleotide-binding oligomerization domain-like receptors (NLRs), retinoic acid-inducible gene-I- (RIG-I-) like receptors (RLRs), and C-type lectin receptors (CLRs). TLRs and NLRs are PRRs that play a key role in recognition of extracellular and intracellular bacteria and control the inflammatory response. The activation of TLRs and NLRs by their respective ligands activates downstream signaling pathways that converge on activation of transcription factors, such as nuclear factor-kappaB (NF-κB), activator protein-1 (AP-1) or interferon regulatory factors (IRFs), leading to expression of inflammatory cytokines and antimicrobial molecules. The goal of this review is to discuss how the TLRs and NRLs signaling pathways collaborate in a cooperative or synergistic manner to counteract the infectious agents. A deep knowledge of the biochemical events initiated by each of these receptors will undoubtedly have a high impact in the design of more effective strategies to control inflammation.
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Redgrove KA, McLaughlin EA. The Role of the Immune Response in Chlamydia trachomatis Infection of the Male Genital Tract: A Double-Edged Sword. Front Immunol 2014; 5:534. [PMID: 25386180 PMCID: PMC4209867 DOI: 10.3389/fimmu.2014.00534] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 10/09/2014] [Indexed: 01/16/2023] Open
Abstract
Chlamydia trachomatis (CT) is the most prevalent bacterial sexually transmitted infection in the world, with more than 100 million cases reported annually. While there have been extensive studies into the adverse effects that CT infection has on the female genital tract, and on the subsequent ability of these women to conceive, studies into the consequences on male fertility have been limited and controversial. This is in part due to the asymptomatic nature of the infection, where it is estimated that 50% of men with Chlamydia fail to show any symptoms. It is accepted, however, that acute and/or persistent CT infection is the causative agent for conditions such as urethritis, epididymitis, epididymo-orchitis, and potentially prostatitis. As with most infections, the immune system plays a fundamental role in the body’s attempts to eradicate the infection. The first and most important immune response to Chlamydia infection is a local one, whereby immune cells such as leukocytes are recruited to the site of infections, and subsequently secrete pro-inflammatory cytokines and chemokines such as interferon gamma. Immune cells also work to initiate and potentiate chronic inflammation through the production of reactive oxygen species (ROS), and the release of molecules with degradative properties including defensins, elastase, collagenase, cathespins, and lysozyme. This long-term inflammation can lead to cell proliferation (a possible precursor to cancer), tissue remodeling, and scarring, as well as being linked to the onset of autoimmune responses in genetically disposed individuals. This review will focus on the ability of the immune system to recognize and clear acute and persistent chlamydial infections in the male genital tract, and on the paradoxical damage that chronic inflammation resulting from the infection can cause on the reproductive health of the individual.
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Affiliation(s)
- Kate A Redgrove
- Priority Research Centre in Reproductive Biology and Chemical Biology, University of Newcastle , Callaghan, NSW , Australia ; School of Environmental and Life Science, University of Newcastle , Callaghan, NSW , Australia
| | - Eileen A McLaughlin
- Priority Research Centre in Reproductive Biology and Chemical Biology, University of Newcastle , Callaghan, NSW , Australia ; School of Environmental and Life Science, University of Newcastle , Callaghan, NSW , Australia
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Chaput C, Sander LE, Suttorp N, Opitz B. NOD-Like Receptors in Lung Diseases. Front Immunol 2013; 4:393. [PMID: 24312100 PMCID: PMC3836004 DOI: 10.3389/fimmu.2013.00393] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 11/07/2013] [Indexed: 12/15/2022] Open
Abstract
The lung is a particularly vulnerable organ at the interface of the body and the exterior environment. It is constantly exposed to microbes and particles by inhalation. The innate immune system needs to react promptly and adequately to potential dangers posed by these microbes and particles, while at the same time avoiding extensive tissue damage. Nucleotide-binding oligomerization domain-like receptors (NLRs) represent a group of key sensors for microbes and damage in the lung. As such they are important players in various infectious as well as acute and chronic sterile inflammatory diseases, such as pneumonia, chronic obstructive pulmonary disease (COPD), acute lung injury/acute respiratory distress syndrome, pneumoconiosis, and asthma. Activation of most known NLRs leads to the production and release of pro-inflammatory cytokines, and/or to the induction of cell death. We will review NLR functions in the lung during infection and sterile inflammation.
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Affiliation(s)
- Catherine Chaput
- Department of Internal Medicine/Infectious Diseases and Pulmonary Medicine, Charité - Universitätsmedizin Berlin , Berlin , Germany
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Campbell LA, Lee AW, Rosenfeld ME, Kuo CC. Chlamydia pneumoniae induces expression of pro-atherogenic factors through activation of the lectin-like oxidized LDL receptor-1. Pathog Dis 2013; 69:1-6. [PMID: 23821487 DOI: 10.1111/2049-632x.12058] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 06/21/2013] [Accepted: 06/21/2013] [Indexed: 11/29/2022] Open
Abstract
Several lines of evidence have associated Chlamydia pneumoniae with cardiovascular disease including acceleration of atherosclerotic lesion progression in hyperlipidemic animal models by infection. Many of the pro-atherogenic effects of oxidized low-density lipoprotein (ox-LDL) occur through the activation of the lectin-like ox-LDL receptor-1 (LOX-1). Chlamydia pneumoniae upregulates the expression of the LOX-1 mRNA, promotes the uptake of ox-LDL, and utilizes the LOX-1 receptor for infectivity. The overall goal of this study was to determine whether C. pneumoniae organisms upregulated LOX-1 protein expression in vascular cells and whether upregulation of pro-atherogenic factors by C. pneumoniae occurred through LOX-1. Chlamydia pneumoniae induced LOX-1 protein expression in both endothelial cells and RAW macrophages. Upregulation was prevented by preincubation of cells with LOX-1 antibody prior to infection. Similarly, C. pneumoniae upregulated protein expression of adhesion molecules, MMP-1, and MMP-3, which was mitigated by anti-LOX-1 antibody. Prior treatment of organisms with PNGase, which removes the chlamydial glycan that is N-linked to the major outer membrane, abolished C. pneumoniae upregulation of LOX-1. These studies suggest that activation of LOX-1 expression occurs through binding of the chlamydial glycan and provides one mechanism by which C. pneumoniae infection could play a role in the pathogenesis of atherosclerosis.
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Affiliation(s)
- Lee A Campbell
- Department of Epidemiology, University of Washington, Seattle, WA, USA
| | - Amy W Lee
- Department of Epidemiology, University of Washington, Seattle, WA, USA
| | | | - Cho-Chou Kuo
- Department of Epidemiology, University of Washington, Seattle, WA, USA
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Jiang SJ, Campbell LA, Berry MW, Rosenfeld ME, Kuo CC. Retinoic acid prevents Chlamydia pneumoniae-induced foam cell development in a mouse model of atherosclerosis. Microbes Infect 2008; 10:1393-7. [PMID: 18678272 PMCID: PMC2600450 DOI: 10.1016/j.micinf.2008.07.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Accepted: 07/07/2008] [Indexed: 11/27/2022]
Abstract
Chlamydia pneumoniae, a common respiratory pathogen, has been associated with cardiovascular disease. C. pneumoniae infection accelerates atherosclerotic lesion development in hyperlipidemic animals. Retinoic acid, an anti-oxidant, inhibits infection of endothelial cells by C. pneumoniae. The present study demonstrated that retinoic acid suppresses the acceleration of foam cell lesion development induced by C. pneumoniae in hyperlipidemic C57BL/6J mice. Retinoic acid treatment had no effect on foam cell lesion development in uninfected animals. Lung infection and duration was decreased in treated mice, suggesting one mechanism by which retinoic acid reduces C. pneumoniae-accelerated foam cell lesion formation in hyperlipidemic mice.
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Affiliation(s)
- Shinn-Jong Jiang
- Department of Pathobiology, University of Washington, Box 357238, Seattle, WA 98195, USA
| | - Lee Ann Campbell
- Department of Pathobiology, University of Washington, Box 357238, Seattle, WA 98195, USA
- Department of Epidemiology, University of Washington, Box 357236, Seattle, WA 98195, USA
| | - Mark W. Berry
- Department of Pathobiology, University of Washington, Box 357238, Seattle, WA 98195, USA
- Department of Epidemiology, University of Washington, Box 357236, Seattle, WA 98195, USA
| | - Michael E. Rosenfeld
- Department of Pathobiology, University of Washington, Box 357238, Seattle, WA 98195, USA
- Department of Pathology, University of Washington, Box 357470, Seattle, WA 98195, USA
| | - Cho-Chou Kuo
- Department of Pathobiology, University of Washington, Box 357238, Seattle, WA 98195, USA
- Department of Epidemiology, University of Washington, Box 357236, Seattle, WA 98195, USA
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9
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Puolakkainen M, Lee A, Nosaka T, Fukushi H, Kuo CC, Campbell LA. Retinoic acid inhibits the infectivity and growth of Chlamydia pneumoniae in epithelial and endothelial cells through different receptors. Microb Pathog 2007; 44:410-6. [PMID: 18162363 DOI: 10.1016/j.micpath.2007.11.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2007] [Revised: 11/06/2007] [Accepted: 11/09/2007] [Indexed: 10/22/2022]
Abstract
Chlamydia pneumoniae is a human respiratory pathogen that has also been associated with cardiovascular disease. C. pneumoniae infection accelerates atherosclerotic plaque development in hyperlipidemic animals and promotes oxidation of low density lipoprotein in vitro. All-trans-retinoic acid (ATRA), an antioxidant, has been shown to inhibit C. pneumoniae infectivity for endothelial cells by preventing binding of the organism to the M6P/IGF2 receptor on the cell surface. This current study investigates whether ATRA similarly affects C. pneumoniae infectivity of epithelial cells, which are the primary site of infection in the respiratory tract, and the effects on intracellular growth in both endothelial and epithelial cells. Because ATRA binds to both the nuclear retinoid acid receptor (RAR) and the M6P/IGF2 receptor, 4-[(E)-2-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)-1-propenyl]benzoic acid (TTNPB), an ATRA analog, which binds to the RAR but not the M6P/IGF2 receptor was used to differentiate the receptor mediating the effects of ATRA. The results of this study showed two separate effects of ATRA. The first effect is through interaction with the M6P/IGF2 receptor on the cell surface preventing attachment of the organism (inhibition by ATRA but not TTNPB) in endothelial cells and the second is through the nuclear receptor (inhibition by both ATRA and TTNPB) which inhibits growth in both epithelial and endothelial cells.
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Affiliation(s)
- Mirja Puolakkainen
- Department of Pathobiology, University of Washington, Box 357238, Seattle, WA 91895, USA
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Gérard HC, Fomicheva E, Whittum-Hudson JA, Hudson AP. Apolipoprotein E4 enhances attachment of Chlamydophila (Chlamydia) pneumoniae elementary bodies to host cells. Microb Pathog 2007; 44:279-85. [PMID: 17997273 DOI: 10.1016/j.micpath.2007.10.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2007] [Accepted: 10/08/2007] [Indexed: 11/17/2022]
Abstract
Chlamydophila (Chlamydia) pneumoniae is an intracellular respiratory pathogen known to cause community-acquired pneumonia. Infection with this organism has been associated with atherosclerosis, inflammatory arthritis, and other chronic diseases, many of which also have been associated with possession of the epsilon4 allele at the APOE locus on (human) chromosome 19. An earlier study from this laboratory suggested that some relationship exists between apolipoprotein E4 (apoE4), the product of the epsilon4 allele, and the pathobiology of C. pneumoniae. A standard attachment assay and real time PCR targeting a sequence on the C. pneumoniae chromosome were used to monitor host cell binding of elementary bodies (EB) of that organism. Our data indicate that 3-fold more EB of strain AR-39 attach to an epsilon3 homozygous human cell line transfected with a plasmid expressing the epsilon4 coding sequence than to the same cell line harboring empty vector, vector containing an irrelevant insert sequence, or vector containing the DNA sequence encoding apoE3. The quantitative real time data were confirmed by immunolabeling of chlamydial inclusions in parallel attachment and infection assays. Experiments using Chlamydophila trachomatis EB showed no enhancement of attachment in the presence of the epsilon4 allele in any assays. These observations indicate that apoE4 enhances attachment of C. pneumoniae EB, but not those of C. trachomatis, to target host cells.
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Affiliation(s)
- Hervé C Gérard
- Department of Immunology and Microbiology, Wayne State University School of Medicine, Wayne State University School of Medicine, Gordon H. Scott Hall, Detroit, MI 48201, USA
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Kuo CC, Lee A, Jiang SJ, Yaraei K, Campbell LA. Inoculation of Chlamydia pneumoniae or Chlamydia trachomatis with ligands that inhibit attachment to host cells reduces infectivity in the mouse model of lung infection: implication for anti-adhesive therapy. Microbes Infect 2007; 9:1139-41. [PMID: 17656142 DOI: 10.1016/j.micinf.2007.04.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2007] [Revised: 04/12/2007] [Accepted: 04/27/2007] [Indexed: 11/21/2022]
Abstract
Previous studies have shown that the chlamydial glycan contains a high-mannose oligosaccharide, which mediates attachment and infectivity of the organism. Removal of the glycan decreases infectivity in vitro and in vivo. The present study demonstrates that simultaneous inoculation of chlamydial organisms and a ligand that prevents glycan binding reduces lung burden in infected animals.
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Affiliation(s)
- Cho-Chou Kuo
- Department of Pathobiology, Box 357238, University of Washington School of Public Health and Community Medicine, Seattle, WA 98195-7238, USA.
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12
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Dreses-Werringloer U, Gérard HC, Whittum-Hudson JA, Hudson AP. Chlamydophila (Chlamydia) pneumoniae Infection of Human Astrocytes and Microglia in Culture Displays an Active, Rather than a Persistent, Phenotype. Am J Med Sci 2006; 332:168-74. [PMID: 17031241 DOI: 10.1097/00000441-200610000-00003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The intracellular pathogen Chlamydia pneumoniae can cause persistent infections during which its morphologic, molecular, and pathogenic characteristics differ importantly from those of active infection. This bacterium was identified within astrocytes and microglia in the brain of late-onset Alzheimer disease patients. We investigated whether infection of these two host cell types displays an active or persistent growth phenotype. METHODS The human astrocytoma and microglioma cell lines U-87 MG and CHME-5 (respectively) and the human epithelial cell line HEp-2 were infected by the standard method with C pneumoniae strain AR-39. Cultures were harvested at 24, 48, and 72 hours postinfection and subjected to analysis of inclusion morphology. DNA and RNA were prepared from portions of each infected culture sample and analyzed for relative chromosome accumulation and presence or absence of several specific bacterial mRNAs. RESULTS Astrocytes and microglial cells infected in vitro with C pneumoniae displayed inclusions that were indistinguishable from those characteristic of active infection of the standard HEp-2 host cell line. Real time polymerase chain reaction (PCR) showed that the relative accumulation of chlamydial chromosome over time during infection of these two cell lines also was virtually identical to that in actively infected HEp-2 cells. Reverse transcriptase PCR (RT-PCR) analyses showed that mRNA from ftsK, pyk, and other chlamydial genes whose expression is abrogated during persistent infection were easily identifiable in infected CHME-5 and U-87 MG cells. CONCLUSIONS In cultured human astrocytes and microglia, C pneumoniae displays an active, not a persistent, growth phenotype. This indicates normal passage through the developmental cycle with its probable concomitant destruction by lysis of some portion of host cells at the termination of that cycle.
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Affiliation(s)
- Ute Dreses-Werringloer
- Department of Immunology and Microbiology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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Campbell LA, Lee A, Kuo CC. Cleavage of the N-linked oligosaccharide from the surfaces of Chlamydia species affects infectivity in the mouse model of lung infection. Infect Immun 2006; 74:3027-9. [PMID: 16622244 PMCID: PMC1459694 DOI: 10.1128/iai.74.5.3027-3029.2006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Previous studies determined that the Chlamydia glycan contains a high-mannose oligosaccharide, which is involved in attachment and infectivity of the organism, and that removal of the glycan decreases infectivity in vitro. The present study demonstrates that treatment of the organism with N-glycanase decreases or ablates infectivity in vivo.
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Affiliation(s)
- Lee Ann Campbell
- Department of Pathobiology, University of Washington, Box 357238, Seattle, WA 98195, USA.
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14
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Abstract
Chlamydia are widespread bacteria that grow in human and animal cells. They enter their host cell, establish an intracellular environment favourable for their multiplication and finally exit the host cell. A combination of host cell factors and of bacterial proteins contribute to pathogen entry. Recent advances have shed new light on the entry mechanism, following attachment. Here we review recent data concerning endocytosis, host cell signalling, proteins secreted by the bacteria, the actin cytoskeleton in entry and the involvement of small GTPases.
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Affiliation(s)
- Alice Dautry-Varsat
- Unité de Biologie des Interactions Cellulaires, Institut Pasteur, URA CNRS 2582, 25 rue du Docteur Roux, 75724 Paris Cedex 15, France.
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15
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Oberley RE, Goss KL, Dahmoush L, Ault KA, Crouch EC, Snyder JM. A role for surfactant protein D in innate immunity of the human prostate. Prostate 2005; 65:241-51. [PMID: 15948134 DOI: 10.1002/pros.20292] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVES Surfactant protein D (SP-D) is a member of the collectin family of proteins, which are involved in host defense mechanisms in the lung. In the present study, we found that SP-D is produced in the human prostate where it may play a role in innate immunity. METHODS AND RESULTS Using reverse-transcriptase PCR and Western blot analysis, we demonstrate that SP-D mRNA and protein are present in human prostate tissue. In situ hybridization and immunohistochemistry revealed that SP-D mRNA and protein are localized in epithelial cells of prostate glands. Prostate glands that are surrounded by inflammatory cells produce increased amounts of SP-D protein. We also show that SP-D inhibits the infection of LNCaP and P69SV40T prostate epithelial cells by Chlamydia trachomatis in an in vitro infection assay. Furthermore, using truncated human SP-D mutants, we demonstrate that SP-D binds to Chlamydia trachomatis via its carboxy-terminal lectin domains. CONCLUSIONS Our in vitro studies suggest that SP-D protects the prostate from infection by pathogens. SP-D protein levels are increased at sites of inflammation in the prostate, suggesting SP-D may also contribute more generally to inflammatory regulation in the prostate.
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Affiliation(s)
- Rebecca E Oberley
- Department of Anatomy and Cell Biology, University of Iowa College of Medicine, Iowa City, Iowa 52242, USA
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