scholarly journals Effect of Sugars on Chlamydia trachomatis Infectivity

Pathogens ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 298
Author(s):  
Giacomo Marziali ◽  
Antonella Marangoni ◽  
Claudio Foschi ◽  
Maria Carla Re ◽  
Natalia Calonghi
Keyword(s):  
Chlamydia Trachomatis ◽  
Membrane Fluidity ◽  
Focal Adhesion ◽  
Hela Cells ◽  
Fluorescence Anisotropy ◽  
Molecular Mechanisms ◽  
Host Cells ◽  
Phosphorylation State ◽  
Anisotropy Measurement ◽  
Membrane Exposure

Background. Previous works suggest that sugars can have a beneficial effect on C. trachomatis (CT) survival and virulence. In this study, we investigated the effect of different sugars on CT infectivity, elucidating some of the molecular mechanisms behind CT-sugar interaction. Methods. CT infectivity was investigated on HeLa cells after 2 hour-incubation of elementary bodies (EBs) with glucose, sucrose, or mannitol solutions (0.5, 2.5, 5.0 mM). The effect of sugars on EB membrane fluidity was investigated by fluorescence anisotropy measurement, whereas the changes in lipopolysaccharide (LPS) exposure were examined by cytofluorimetric analysis. By means of a Western blot, we explored the phosphorylation state of Focal Adhesion Kinase (FAK) in HeLa cells infected with EBs pre-incubated with sugars. Results. All sugar solutions significantly increased CT infectivity on epithelial cells, acting directly on the EB structure. Sugars induced a significant increase of EB membrane fluidity, leading to changes in LPS membrane exposure. Especially after incubation with sucrose and mannitol, EBs led to a higher FAK phosphorylation, enhancing the activation of anti-apoptotic and proliferative signals in the host cells. Conclusions. Sugars can increase CT infectivity and virulence, by modulating the expression/exposure of chlamydial membrane ligands. Further in-depth studies are needed to better understand the molecular mechanisms involved.

scholarly journals Identification of differentially expressed circular RNAs in HeLa cells infected with Chlamydia trachomatis

2019 ◽  
Vol 77 (7) ◽  
Author(s):  
Yuanjun Liu ◽  
Chunmin Hu ◽  
Yina Sun ◽  
Haoqing Wu ◽  
Xiaojun Chen ◽  
...  
Keyword(s):  
Chlamydia Trachomatis ◽  
Signaling Pathways ◽  
Hela Cells ◽  
Expression Profiles ◽  
Quantitative Polymerase Chain Reaction ◽  
Host Cells ◽  
Differentially Expressed ◽  
Chlamydia Infection ◽  
Circular Rnas ◽  
Mrna Microarray

ABSTRACT Non-coding circular RNAs (circRNAs) have been shown to have important roles in many diseases; however, no study has indicated circRNAs are involved in Chlamydia trachomatis infection. In this study, we used circRNA microarray to measure the global circRNA expression profiles in HeLa cells with or without C. trachomatis serovar E (Ct.E) infection. CircRNA/miRNA/mRNA interactions were predicted and bioinformatics analyses were performed. The differentially expressed circRNAs were selected according to our criterion for validation by reverse-transcription and quantitative polymerase chain reaction (RT-qPCR). The mRNA microarray was used to detect the mRNA expression profiles after Ct.E infection. Among 853 differentially expressed circRNAs, 453 were upregulated and 400 were downregulated after Ct.E infection. Target miRNAs and miRNA-targeted mRNAs of these circRNAs were predicted. RT-qPCR analysis indicated hsa_circRNA_001226, hsa_circRNA_007046 and hsa_circRNA_400027 were elevated similar to those determined in the circRNA microarray analysis. The mRNA microarray results showed 915 genes were upregulated and 619 genes were downregulated after Ct.E infection. Thirty-four differentially expressed genes overlapped in the bioinformatics and mRNA microarray results. KEGG pathway analysis revealed several signaling pathways, including endocytosis, MAPK and PI3P-Akt signaling pathways, that were targeted by circRNAs may play important roles in Chlamydia infection. This study provides evidence that circRNAs in host cells are involved in the process of Chlamydia infection.

scholarly journals Role of High-Mobility Group Box 1 Protein and Poly(ADP-Ribose) Polymerase 1 Degradation in Chlamydia trachomatis-Induced Cytopathicity

2010 ◽  
Vol 78 (7) ◽  
pp. 3288-3297 ◽  
Author(s):  
Hangxing Yu ◽  
Katja Schwarzer ◽  
Martin Förster ◽  
Olaf Kniemeyer ◽  
Vera Forsbach-Birk ◽  
...  
Keyword(s):  
Chlamydia Trachomatis ◽  
Cell Membrane ◽  
Hela Cells ◽  
High Mobility ◽  
Host Cells ◽  
High Mobility Group ◽  
Cell Membrane Permeability ◽  
Dependent Manner ◽  
Infected Cells ◽  
Parp 1

ABSTRACT As intracellular bacteria, chlamydiae block the apoptotic pathways of their host cells. However, the infection of epithelial cells causes the loss of cell membrane integrity and can result in nonapoptotic death. Normally, cells undergoing necrosis release high-mobility group box 1 protein (HMGB1) that acts as an important proinflammatory mediator. Here, we show that in Chlamydia trachomatis-infected HeLa cells HMGB1 is not translocated from the nucleus to the cytosol and not released from injured cells in increased amounts. At 48 h after infection, degradation of HMGB1 was observed. In infected cells, poly(ADP-ribose) polymerase 1 (PARP-1), a DNA repair enzyme that also regulates HMGB1 translocation, was found to be cleaved into fragments that correspond to a necrosislike pattern of PARP-1 degradation. Cell-free cleavage assays and immunoprecipitation using purified proteolytic fractions from infected cells demonstrated that the chlamydial-protease-like activity factor (CPAF) is responsible for the cleavage of both HMGB1 and PARP-1. Proteolytic cleavage of PARP-1 was accompanied by a significant decrease in the enzymatic activity in a time-dependent manner. The loss of PARP-1 function obviously affects the viability of Chlamydia-infected cells because silencing of PARP-1 in uninfected HeLa cells with specific small interfering RNA results in increased cell membrane permeability. Our findings suggest that the Chlamydia-specific protease CPAF interferes with necrotic cell death pathways. By the degradation of HMGB1 and PARP-1, the pathogen may have evolved a strategy to reduce the inflammatory response to membrane-damaged cells in vivo.

scholarly journals Long Non-Coding RNA FGD5-AS1 Induced by Chlamydia trachomatis Infection Inhibits Apoptosis via Wnt/β-Catenin Signaling Pathway

2021 ◽  
Vol 11 ◽  
Author(s):  
Yating Wen ◽  
Fangzhen Luo ◽  
Lanhua Zhao ◽  
Shengmei Su ◽  
Wenbo Lei ◽  
...  
Keyword(s):  
Dna Replication ◽  
Network Analysis ◽  
Chlamydia Trachomatis ◽  
Signaling Pathway ◽  
Hela Cells ◽  
Expression Profiles ◽  
Wnt Signaling Pathway ◽  
Host Cells ◽  
Transmitted Infection ◽  
Chlamydia Trachomatis Infection

BackgroundChlamydia trachomatis (Ct) is one of the most common bacterial sexually transmitted infection (STI) pathogens in the world, but the exact pathogenic mechanism still needs to be further elucidated. Long non-coding RNAs (lncRNAs) have become vital regulators in many biological processes. Their role in the interaction between Ct and host cells has not been reported.MethodsMicroarrays were used to study the expression profiles of lncRNAs and mRNAs in HeLa cells at 12, 24, and 40 h post-infection (hpi). Differentially expressed lncRNAs and mRNAs were verified by RT-qPCR. Coding-non-coding (CNC) network analysis showed co-expression molecules of selected lncRNA. Western blot, flow cytometry, and indirect immunofluorescence were used to detect the effect of lncRNA FGD5-AS1 on apoptosis during Ct infection.ResultsCompared with the uninfected group, the number of differential lncRNAs were 2,130, 1,081, and 1,101 at 12, 24, and 40 hpi, and the number of differential mRNAs was 1,998, 1,129, and 1,330, respectively. Ct induced differential expression of large amounts of lncRNAs and mRNAs in HeLa cells, indicating that lncRNAs may play roles in the pathogenesis of Ct. RT-qPCR verified six differential lncRNAs and six differential mRNAs, confirming the reliability of the microarray. Among these molecules, lncRNA FGD5-AS1 was found to be upregulated at 12 and 24 hpi. Coding-non-coding (CNC) network analysis showed that co-expressed differential molecules of FGD5-AS1 at 12 and 24 hpi were enriched in the DNA replication and Wnt signaling pathway. The downregulation of FGD5-AS1 decreased the expression of β-catenin and inhibited the translocation of β-catenin and the DNA replication, while it promoted apoptosis of the host cells.ConclusionsDNA replication and apoptosis of host cells were affected by upregulating FGD5-AS1 via Wnt/β-catenin pathway during Ct infection. This study provides evidence that lncRNAs are involved in the coaction between Ct and hosts, and provides new insights into the study of lncRNAs that regulate chlamydial infection.

scholarly journals Entry of the Lymphogranuloma Venereum Strain of Chlamydia trachomatis into Host Cells Involves Cholesterol-Rich Membrane Domains

2003 ◽  
Vol 71 (1) ◽  
pp. 260-266 ◽  
Author(s):  
Isabelle Jutras ◽  
Laurence Abrami ◽  
Alice Dautry-Varsat
Keyword(s):  
Chlamydia Trachomatis ◽  
Hela Cells ◽  
Chlamydia Psittaci ◽  
Host Cells ◽  
Membrane Domains ◽  
Lipid Domains ◽  
Bacterial Cells ◽  
Coated Pits ◽  
Lipid Microdomains ◽  
Plasma Membrane Cholesterol

ABSTRACT Chlamydiae are bacterial pathogens which develop strictly inside the epithelial cells of their hosts. The mechanism used by chlamydiae to enter cells is not well characterized; however, it is thought to consist of a receptor-mediated process. In addition, the formation of clathrin-coated pits appears to be dispensable for chlamydiae to be internalized by host cells. Clathrin-independent endocytosis has recently been shown to occur through cholesterol-rich lipid microdomains, which are characterized by detergent insolubility. In the present study, we investigated whether these lipid domains play a role in Chlamydia trachomatis serovar L2 internalization by host cells. Our results show that after binding to HeLa cells, chlamydiae are associated with detergent-resistant lipid microdomains (DRMs), which can be isolated by fractionation of infected HeLa cells and flotation on a sucrose gradient. After internalization by HeLa cells, chlamydiae were still found in DRMs. In addition, extraction of plasma membrane cholesterol inhibited infection of HeLa cells by C. trachomatis. Many of the proteins associated with DRMs are glycosylphosphatidylinositol (GPI)-anchored proteins; however, our results could not identify a role for GPI-anchored proteins in the entry process. The same results were obtained for Chlamydia psittaci strain GPIC. We propose that cholesterol-rich domains participate in the entry of chlamydiae into host cells. Chlamydia binding to cholesterol-rich domains may lead to coalescence of the bacterial cells, which could trigger internalization by host cells.

scholarly journals Differences in Chlamydia trachomatis Serovar E Growth Rate in Polarized Endometrial and Endocervical Epithelial Cells Grown in Three-Dimensional Culture

2006 ◽  
Vol 75 (2) ◽  
pp. 553-564 ◽  
Author(s):  
Natalia V. Guseva ◽  
Sophie Dessus-Babus ◽  
Cheryl G. Moore ◽  
Judy D. Whittimore ◽  
Priscilla B. Wyrick
Keyword(s):  
Chlamydia Trachomatis ◽  
Epithelial Cell ◽  
Cell Lines ◽  
Hela Cells ◽  
Culture System ◽  
Three Dimensional ◽  
Host Cells ◽  
Developmental Cycle ◽  
Epithelial Cell Lines ◽  
Three Dimensional Culture

ABSTRACT In vitro studies of obligate intracellular chlamydia biology and pathogenesis are highly dependent on the use of experimental models and growth conditions that mimic the mucosal architecture and environment these pathogens encounter during natural infections. In this study, the growth of Chlamydia trachomatis genital serovar E was monitored in mouse fibroblast McCoy cells and compared to more relevant host human epithelial endometrium-derived HEC-1B and cervix-derived HeLa cells, seeded and polarized on collagen-coated microcarrier beads, using a three-dimensional culture system. Microscopy analysis of these cell lines prior to infection revealed morphological differences reminiscent of their in vivo architecture. Upon infection, early chlamydial inclusion distribution was uniform in McCoy cells but patchy in both epithelial cell lines. Although no difference in chlamydial attachment to or entry into the two genital epithelial cell lines was noted, active bacterial genome replication and transcription, as well as initial transformation of elementary bodies to reticulate bodies, were detected earlier in HEC-1B than in HeLa cells, suggesting a faster growth, which led to higher progeny counts and titers in HEC-1B cells upon completion of the developmental cycle. Chlamydial development in the less relevant McCoy cells was very similar to that in HeLa cells, although higher progeny counts were obtained. In conclusion, this three-dimensional bead culture system represents an improved model for harvesting large quantities of infectious chlamydia progeny from their more natural polarized epithelial host cells.

scholarly journals Perforin-2 Restricts Growth of Chlamydia trachomatis in Macrophages

2013 ◽  
Vol 81 (8) ◽  
pp. 3045-3054 ◽  
Author(s):  
K. A. Fields ◽  
R. McCormack ◽  
L. R. de Armas ◽  
E. R. Podack
Keyword(s):  
Chlamydia Trachomatis ◽  
Epithelial Cells ◽  
Hela Cells ◽  
Ectopic Expression ◽  
Host Cells ◽  
Content Type ◽  
Obligate Intracellular ◽  
Novel Host ◽  
Defense Protein ◽  
Resistance Protein

ABSTRACTChlamydia trachomatisis a Gram-negative obligate intracellular bacterium that preferentially infects epithelial cells. Professional phagocytes provideC. trachomatisonly a limited ability to survive and are proficient killers of chlamydiae. We present evidence herein that identifies a novel host defense protein, perforin-2, that plays a significant role in the eradication ofC. trachomatisduring the infection of macrophages. Knockdown of perforin-2 in macrophages did not alter the invasion of host cells but did result in chlamydial growth that closely mirrored that detected in HeLa cells.C trachomatisL2, serovar B, and serovar D andC. muridarumwere all equally susceptible to perforin-2-mediated killing. Interestingly, induction of perforin-2 expression in epithelial cells is blocked during productive chlamydial growth, thereby protecting chlamydiae from bactericidal attack. Ectopic expression of perforin-2 in HeLa cells, however, does result in killing. Overall, our data implicate a new innate resistance protein in the control of chlamydial infection and may help explain why the macrophage environment is hostile to chlamydial growth.

scholarly journals Chlamydia trachomatis OmcB protein is a surface-exposed glycosaminoglycan-dependent adhesin

2007 ◽  
Vol 56 (1) ◽  
pp. 15-22 ◽  
Author(s):  
Sanaa Fadel ◽  
Adrian Eley
Keyword(s):  
Escherichia Coli ◽  
Chlamydia Trachomatis ◽  
Outer Membrane ◽  
Hela Cells ◽  
Polyclonal Antibodies ◽  
Full Length ◽  
Host Cells ◽  
Gene Encoding ◽  
Antigenic Properties ◽  
Entire Gene

The OmcB protein of Chlamydia trachomatis is a cysteine-rich outer membrane polypeptide with important functional, structural and antigenic properties. The entire gene encoding the OmcB protein from C. trachomatis serovar LGV1 was cloned and expressed in Escherichia coli and the full-length protein used to raise polyclonal antibodies. Recombinant OmcB was used to show that OmcB is a surface-exposed protein that functions as a chlamydial adhesin. Infectivity inhibition assays carried out using HeLa cells with serovar LGV1 in the presence of purified anti-OmcB serum showed inhibition of infectivity, suggesting that some of the OmcB was surface exposed. Moreover, using recombinant OmcB in infectivity inhibition assays resulted in 70 % inhibition of infectivity, confirming that OmcB plays a role as an adhesin in C. trachomatis. Furthermore, recombinant OmcB protein bound to the surface of HeLa and Hec1B cells, but binding to glycosaminoglycan (GAG)-deficient cells (pgsA-745 and pgsD-677) was markedly reduced, indicating that OmcB binds to GAG-like receptors on host cells.

scholarly journals Xyloglucan processing machinery in Xanthomonas pathogens and its role in the transcriptional activation of virulence factors

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Plinio S. Vieira ◽  
Isabela M. Bonfim ◽  
Evandro A. Araujo ◽  
Ricardo R. Melo ◽  
Augusto R. Lima ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Transcriptional Activation ◽  
Molecular Mechanisms ◽  
Model Organism ◽  
Citrus Canker ◽  
Effector Proteins ◽  
Glycoside Hydrolases ◽  
Host Cells ◽  
System A ◽  
Enzymatic Machinery

AbstractXyloglucans are highly substituted and recalcitrant polysaccharides found in the primary cell walls of vascular plants, acting as a barrier against pathogens. Here, we reveal that the diverse and economically relevant Xanthomonas bacteria are endowed with a xyloglucan depolymerization machinery that is linked to pathogenesis. Using the citrus canker pathogen as a model organism, we show that this system encompasses distinctive glycoside hydrolases, a modular xyloglucan acetylesterase and specific membrane transporters, demonstrating that plant-associated bacteria employ distinct molecular strategies from commensal gut bacteria to cope with xyloglucans. Notably, the sugars released by this system elicit the expression of several key virulence factors, including the type III secretion system, a membrane-embedded apparatus to deliver effector proteins into the host cells. Together, these findings shed light on the molecular mechanisms underpinning the intricate enzymatic machinery of Xanthomonas to depolymerize xyloglucans and uncover a role for this system in signaling pathways driving pathogenesis.

scholarly journals The Inhibitory Effect of a Novel Polypeptide Fraction fromArca subcrenataon Cancer-Related Inflammation in Human Cervical Cancer HeLa Cells

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Yu Wu ◽  
Xianjing Hu ◽  
Liyan Song ◽  
Jianhua Zhu ◽  
Rongmin Yu
Keyword(s):  
Cervical Cancer ◽  
Hela Cells ◽  
Molecular Mechanisms ◽  
Tumor Development ◽  
Basic Research ◽  
Inhibitory Effect ◽  
Fishery Resource ◽  
Proinflammatory Mediators ◽  
Raw264.7 Macrophage ◽  
Human Cervical Cancer

Inflammation is known to be closely associated with the development of cancer. The study was launched in human cervical cancer HeLa cells to investigate the antitumor and anti-inflammatory effects of P2, a marine polypeptide fraction from an important fishery resourceArca subcrenata. The basic research showed that P2 could suppress the production of nitric oxide in LPS-induced RAW264.7 macrophage cells as well as the secretion of inflammatory cytokines IL-6 and TNF-αin human cervical cancer HeLa cells. For the molecular mechanisms, P2 was shown to downregulate the gene expression of proinflammatory cytokines IL-6 and IL-8 and to inhibit the COX-2 and iNOS-related pathways in HeLa cells. In consequence, P2 might inhibit tumor development by blocking the interaction between tumor microenvironment and proinflammatory mediators. All findings indicate that P2 possesses the potential to be developed as a novel agent for cancer therapy.

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