Bordetella pertussis Naturally Occurring Isolates with Altered Lipooligosaccharide Structure Fail To Fully Mature Human Dendritic Cells

Bordetella pertussisis a Gram-negative bacterium and the causative agent of whooping cough. Despite high vaccination coverage, outbreaks are being increasingly reported worldwide. Possible explanations include adaptation of this pathogen, which may interfere with recognition by the innate immune system. Here, we describe innate immune recognition and responses to differentB. pertussisclinical isolates. By using HEK-Blue cells transfected with different pattern recognition receptors, we found that 3 out of 19 clinical isolates failed to activate Toll-like receptor 4 (TLR4). These findings were confirmed by using the monocytic MM6 cell line. Although incubation with high concentrations of these 3 strains resulted in significant activation of the MM6 cells, it was found to occur mainly through interaction with TLR2 and not through TLR4. When using live bacteria, these 3 strains also failed to activate TLR4 on HEK-Blue cells, and activation of MM6 cells or human monocyte-derived dendritic cells was significantly lower than activation induced by the other 16 strains. Mass spectrum analysis of the lipid A moieties from these 3 strains indicated an altered structure of this molecule. Gene sequence analysis revealed mutations in genes involved in lipid A synthesis. Findings from this study indicate thatB. pertussisisolates that do not activate TLR4 occur naturally and that this phenotype may give this bacterium an advantage in tempering the innate immune response and establishing infection. Knowledge on the strategies used by this pathogen in evading the host immune response is essential for the improvement of current vaccines or for the development of new ones.

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Bordetella pertussis Lipid A Glucosamine Modification Confers Resistance to Cationic Antimicrobial Peptides and Increases Resistance to Outer Membrane Perturbation

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02590-14 ◽

2014 ◽

Vol 58 (8) ◽

pp. 4931-4934 ◽

Cited By ~ 19

Author(s):

Nita R. Shah ◽

Robert E. W. Hancock ◽

Rachel C. Fernandez

Keyword(s):

Immune System ◽

Antimicrobial Peptides ◽

Outer Membrane ◽

Bordetella Pertussis ◽

Lipid A ◽

Whooping Cough ◽

Human Immune System ◽

Cationic Antimicrobial Peptides ◽

Content Type ◽

Membrane Perturbation

ABSTRACTBordetella pertussis, the causative agent of whooping cough, has many strategies for evading the human immune system. Lipopolysaccharide (LPS) is an important Gram-negative bacterial surface structure that activates the immune system via Toll-like receptor 4 and enables susceptibility to cationic antimicrobial peptides (CAMPs). We show modification of the lipid A region of LPS with glucosamine increased resistance to numerous CAMPs, including LL-37. Furthermore, we demonstrate that this glucosamine modification increased resistance to outer membrane perturbation.

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Bordetella pertussis Proteins Dominating the Major Histocompatibility Complex Class II-Presented Epitope Repertoire in Human Monocyte-Derived Dendritic Cells

Clinical and Vaccine Immunology ◽

10.1128/cvi.00665-13 ◽

2014 ◽

Vol 21 (5) ◽

pp. 641-650 ◽

Cited By ~ 11

Author(s):

Rachel M. Stenger ◽

Hugo D. Meiring ◽

Betsy Kuipers ◽

Martien Poelen ◽

Jacqueline A. M. van Gaans-van den Brink ◽

...

Keyword(s):

Dendritic Cells ◽

Major Histocompatibility Complex ◽

T Cell ◽

Bordetella Pertussis ◽

Human Monocyte ◽

Class Ii ◽

T Cell Epitopes ◽

Major Histocompatibility ◽

Content Type ◽

Histocompatibility Complex

ABSTRACTKnowledge of naturally processedBordetella pertussis-specific T cell epitopes may help to increase our understanding of the basis of cell-mediated immune mechanisms to control this reemerging pathogen. Here, we elucidate for the first time the dominant major histocompatibility complex (MHC) class II-presentedB. pertussisCD4+T cell epitopes, expressed on human monocyte-derived dendritic cells (MDDC) after the processing of whole bacterial cells by use of a platform of immunoproteomics technology. Pertussis epitopes identified in the context of HLA-DR molecules were derived from two envelope proteins, i.e., putative periplasmic protein (PPP) and putative peptidoglycan-associated lipoprotein (PAL), and from two cytosolic proteins, i.e., 10-kDa chaperonin groES protein (groES) and adenylosuccinate synthetase (ASS). No epitopes were detectable from known virulence factors. CD4+T cell responsiveness in healthy adults against peptide pools representing epitope regions or full proteins confirmed the immunogenicity of PAL, PPP, groES, and ASS. Elevated lymphoproliferative activity to PPP, groES, and ASS in subjects within a year after the diagnosis of symptomatic pertussis suggested immunogenic exposure to these proteins during clinical infection. The PAL-, PPP-, groES-, and ASS-specific responses were associated with secretion of functional Th1 (tumor necrosis factor alpha [TNF-α] and gamma interferon [IFN-γ]) and Th2 (interleukin 5 [IL-5] and IL-13) cytokines. Relative paucity in the naturalB. pertussisepitope display of MDDC, not dominated by epitopes from known protective antigens, can interfere with the effectiveness of immune recognition ofB. pertussis. A more complete understanding of hallmarks inB. pertussis-specific immunity may advance the design of novel immunological assays and prevention strategies.

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Identification of PGN_1123 as the Gene Encoding Lipid A Deacylase, an Enzyme Required for Toll-Like Receptor 4 Evasion, inPorphyromonas gingivalis

Journal of Bacteriology ◽

10.1128/jb.00683-18 ◽

2019 ◽

Vol 201 (11) ◽

Cited By ~ 3

Author(s):

Sumita Jain ◽

Ana M. Chang ◽

Manjot Singh ◽

Jeffrey S. McLean ◽

Stephen R. Coats ◽

...

Keyword(s):

Immune Response ◽

Porphyromonas Gingivalis ◽

Innate Immune Response ◽

Lipid A ◽

Innate Immune ◽

Toll Like Receptor ◽

Toll Like Receptor 4 ◽

Gene Encoding ◽

Content Type ◽

Chronic Inflammatory Condition

ABSTRACTRemoval of one acyl chain from bacterial lipid A by deacylase activity is a mechanism used by many pathogenic bacteria to evade the host's Toll-like receptor 4 (TLR4)-mediated innate immune response. InPorphyromonas gingivalis, a periodontal pathogen, lipid A deacylase activity converts a majority of the initially synthesized penta-acylated lipid A, a TLR4 agonist, to tetra-acylated structures, which effectively evade TLR4 sensing by being either inert or antagonistic at TLR4. In this paper, we report successful identification of the gene that encodes theP. gingivalislipid A deacylase enzyme. This gene, PGN_1123 inP. gingivalis33277, is highly conserved withinP. gingivalis, and putative orthologs are phylogenetically restricted to theBacteroidetesphylum. Lipid A of ΔPGN_1123 mutants is penta-acylated and devoid of tetra-acylated structures, and the mutant strain provokes a strong TLR4-mediated proinflammatory response, in contrast to the negligible response elicited by wild-typeP. gingivalis. Heterologous expression of PGN_1123 inBacteroides thetaiotaomicronpromoted lipid A deacylation, confirming that PGN_1123 encodes the lipid A deacylase enzyme.IMPORTANCEPeriodontitis, commonly referred to as gum disease, is a chronic inflammatory condition that affects a large proportion of the population.Porphyromonas gingivalisis a bacterium closely associated with periodontitis, although how and if it is a cause for the disease are not known. It has a formidable capacity to dampen the host's innate immune response, enabling its persistence in diseased sites and triggering microbial dysbiosis in animal models of infection.P. gingivalisis particularly adept at evading the host's TLR4-mediated innate immune response by modifying the structure of lipid A, the TLR4 ligand. In this paper, we report identification of the gene encoding lipid A deacylase, a key enzyme that modifies lipid A to TLR4-evasive structures.

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Toll-Like Receptor 6 Plays an Important Role in Host Innate Resistance to Brucella abortus Infection in Mice

Infection and Immunity ◽

10.1128/iai.01356-12 ◽

2013 ◽

Vol 81 (5) ◽

pp. 1654-1662 ◽

Cited By ~ 27

Author(s):

Leonardo A. de Almeida ◽

Gilson C. Macedo ◽

Fábio A. V. Marinho ◽

Marco T. R. Gomes ◽

Patrícia P. Corsetti ◽

...

Keyword(s):

Immune Response ◽

Dendritic Cells ◽

Brucella Abortus ◽

Proinflammatory Cytokine ◽

Cytokine Production ◽

Innate Immune ◽

Proinflammatory Cytokine Production ◽

Toll Like Receptor ◽

Content Type

ABSTRACTBrucella abortusis recognized by several Toll-like receptor (TLR)-associated pathways triggering proinflammatory responses that affect both the nature and intensity of the immune response. Previously, we demonstrated thatB. abortus-mediated dendritic cell (DC) maturation and control of infection are dependent on the adaptor molecule MyD88. However, the involvement of all TLRs in response toB. abortusinfection is not completely understood. Therefore, we decided to evaluate the requirement for TLR6 in host resistance toB. abortus. Here, we demonstrated that TLR6 is an important component for triggering an innate immune response againstB. abortus. Anin vitroluciferase assay indicated that TLR6 cooperates with TLR2 to senseBrucellaand further activates NF-κB signaling. However,in vivoanalysis showed that TLR6, not TLR2, is required for the efficient control ofB. abortusinfection. Additionally,B. abortus-infected dendritic cells require TLR6 to induce tumor necrosis factor alpha (TNF-α) and interleukin-12 (IL-12). Furthermore, our findings demonstrated that the mitogen-activated protein kinase (MAPK) signaling pathway is impaired in TLR2, TLR6, and TLR2/6 knockout (KO) DCs when infected withB. abortus, which may account for the lower proinflammatory cytokine production observed in TLR6 KO mouse dendritic cells. In summary, the results presented here indicate that TLR6 is required to trigger innate immune responses againstB. abortusin vivoand is required for the full activation of DCs to induce robust proinflammatory cytokine production.

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Bordetella pertussis-Infected Human Monocyte-Derived Dendritic Cells Undergo Maturation and Induce Th1 Polarization and Interleukin-23 Expression

Infection and Immunity ◽

10.1128/iai.73.3.1590-1597.2005 ◽

2005 ◽

Vol 73 (3) ◽

pp. 1590-1597 ◽

Cited By ~ 43

Author(s):

Giorgio Fedele ◽

Paola Stefanelli ◽

Fabiana Spensieri ◽

Cecilia Fazio ◽

Paola Mastrantonio ◽

...

Keyword(s):

Dendritic Cells ◽

Bordetella Pertussis ◽

Whooping Cough ◽

Natural Infection ◽

Human Monocyte ◽

Cell Types ◽

Interleukin 10 ◽

Cell Mediated Immunity ◽

T Helper 1 ◽

Cell Functions

ABSTRACT Bordetella pertussis, the causative agent of whooping cough, is internalized by several cell types, including epithelial cells, monocytes, and neutrophils. Although its ability to survive intracellularly is still debated, it has been proven that cell-mediated immunity (CMI) plays a pivotal role in protection. In this study we aimed to clarify the interaction of B. pertussis with human monocyte-derived dendritic cells (MDDC), evaluating the ability of the bacterium to enter MDDC, to survive intracellularly, to interfere with the maturation process and functional activities, and to influence the host immune responses. The results obtained showed that B. pertussis had a low capability to be internalized by—and to survive in—MDDC. Upon contact with the bacteria, immature MDDC were induced to undergo phenotypic maturation and acquired antigen-presenting-cell functions. Despite the high levels of interleukin-10 (IL-10) and the barely detectable levels of IL-12 induced by B. pertussis, the bacterium induced maturation of MDDC and T helper 1 (Th1) polarized effector cells. Gene expression analysis of the IL-12 cytokine family clearly demonstrated that B. pertussis induced high levels of the p40 and p19 subunits of IL-23 yet failed to induce the expression of the p35 subunit of IL-12. Overall our findings show that B. pertussis, even if it survives only briefly in MDDC, promotes the synthesis of IL-23, a newly discovered Th1 polarizing cytokine. A Th1-oriented immune response is thus allowed, relevant in the induction of an adequate CMI response, and typical of protection induced by natural infection or vaccination with whole-cell vaccines.

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Bacillus anthracis Capsule Activates Caspase-1 and Induces Interleukin-1β Release from Differentiated THP-1 and Human Monocyte-Derived Dendritic Cells

Infection and Immunity ◽

10.1128/iai.00956-09 ◽

2009 ◽

Vol 78 (1) ◽

pp. 387-392 ◽

Cited By ~ 12

Author(s):

Min-Hee Cho ◽

Hae-Jeong Ahn ◽

Hyun-Joon Ha ◽

Jungchan Park ◽

Jeong-Hoon Chun ◽

...

Keyword(s):

Immune Response ◽

Dendritic Cells ◽

Bacillus Anthracis ◽

Innate Immune Response ◽

Human Monocyte ◽

Innate Immune ◽

Interleukin 1Β ◽

Dependent Manner ◽

Caspase 1 ◽

Extracellular Release

ABSTRACT The poly-γ-d-glutamic acid (PGA) capsule is one of the major virulence factors of Bacillus anthracis, which causes a highly lethal infection. The antiphagocytic PGA capsule disguises the bacilli from immune surveillance and allows unimpeded growth of bacilli in the host. Recently, efforts have been made to include PGA as a component of anthrax vaccine; however, the innate immune response of PGA itself has been poorly investigated. In this study, we characterized the innate immune response elicited by PGA in the human monocytic cell line THP-1, which was differentiated into macrophages with phorbol 12-myristate 13-acetate (PMA) and human monocyte-derived dendritic cells (hMoDCs). PGA capsules were isolated from the culture supernatant of either the pXO1-cured strain of B. anthracis H9401 or B. licheniformis ATCC 9945a. PGA treatment of differentiated THP-1 cells and hMoDCs led to the specific extracellular release of interleukin-1β (IL-1β) in a dose-dependent manner. Evaluation of IL-1β processing by Western blotting revealed that cleaved IL-1β increased in THP-1 cells and hMoDCs after PGA treatment. Enhanced processing of IL-1β directly correlated with increased activation of its upstream regulator, caspase-1, also known as IL-1β-converting enzyme (ICE). The extracellular release of IL-1β in response to PGA was ICE dependent, since the administration of an ICE inhibitor prior to PGA treatment blocked induction of IL-1β. These results demonstrate that B. anthracis PGA elicits IL-1β production through activation of ICE in PMA-differentiated THP-1 cells and hMoDCs, suggesting the potential for PGA as a therapeutic target for anthrax.

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Hexa-Acylated Lipid A Is Required for Host Inflammatory Response to Neisseria gonorrhoeae in Experimental Gonorrhea

Infection and Immunity ◽

10.1128/iai.00890-13 ◽

2013 ◽

Vol 82 (1) ◽

pp. 184-192 ◽

Cited By ~ 17

Author(s):

Xiyou Zhou ◽

Xi Gao ◽

Peter M. Broglie ◽

Chahnaz Kebaier ◽

James E. Anderson ◽

...

Keyword(s):

Neisseria Gonorrhoeae ◽

Lipid A ◽

Innate Immune ◽

Immune Recognition ◽

Toll Like Receptor ◽

Inflammatory Signaling ◽

Toll Like Receptor 4 ◽

Immune Signaling ◽

Content Type ◽

Innate Immune Signaling

ABSTRACTNeisseria gonorrhoeaecauses gonorrhea, a sexually transmitted infection characterized by inflammation of the cervix or urethra. However, a significant subset of patients withN. gonorrhoeaeremain asymptomatic, without evidence of localized inflammation. Inflammatory responses toN. gonorrhoeaeare generated by host innate immune recognition ofN. gonorrhoeaeby several innate immune signaling pathways, including lipooligosaccharide (LOS) and other pathogen-derived molecules through activation of innate immune signaling systems, including toll-like receptor 4 (TLR4) and the interleukin-1β (IL-1β) processing complex known as the inflammasome. The lipooligosaccharide ofN. gonorrhoeaehas a hexa-acylated lipid A.N. gonorrhoeaestrains that carry an inactivatedmsbB(also known aslpxL1) gene produce a penta-acylated lipid A and exhibit reduced biofilm formation, survival in epithelial cells, and induction of epithelial cell inflammatory signaling. We now show thatmsbB-deficientN. gonorrhoeaeinduces less inflammatory signaling in human monocytic cell lines and murine macrophages than the parent organism. The penta-acylated LOS exhibits reduced toll-like receptor 4 signaling but does not affectN. gonorrhoeae-mediated activation of the inflammasome. We demonstrate thatN. gonorrhoeaemsbBis dispensable for initiating and maintaining infection in a murine model of gonorrhea. Interestingly, infection withmsbB-deficientN. gonorrhoeaeis associated with less localized inflammation. Combined, these data suggest that TLR4-mediated recognition ofN. gonorrhoeaeLOS plays an important role in the pathogenesis of symptomatic gonorrhea infection and that alterations in lipid A biosynthesis may play a role in determining symptomatic and asymptomatic infections.

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Human Monocyte-Derived Dendritic Cells Exposed to Microorganisms Involved in Hypersensitivity Pneumonitis Induce a Th1-Polarized Immune Response

Clinical and Vaccine Immunology ◽

10.1128/cvi.00043-13 ◽

2013 ◽

Vol 20 (8) ◽

pp. 1133-1142 ◽

Cited By ~ 6

Author(s):

Anne-Pauline Bellanger ◽

Jean-René Pallandre ◽

Christophe Borg ◽

Sophie Loeffert ◽

Houssein Gbaguidi-Haore ◽

...

Keyword(s):

Immune Response ◽

Dendritic Cells ◽

Filamentous Fungi ◽

Cross Talk ◽

Hypersensitivity Pneumonitis ◽

Human Monocyte ◽

Costimulatory Molecules ◽

Rank Test ◽

Content Type ◽

Wallemia Sebi

ABSTRACTHypersensitivity pneumonitis (HP) is an immunoallergic disease characterized by a prominent interstitial infiltrate composed predominantly of lymphocytes secreting inflammatory cytokines. Dendritic cells (DCs) are known to play a pivotal role in the lymphocytic response. However, their cross talk with microorganisms that cause HP has yet to be elucidated. This study aimed to investigate the initial interactions between human monocyte-derived DCs (MoDCs) and four microorganisms that are different in nature (Saccharopolyspora rectivirgula[actinomycetes],Mycobacterium immunogenum[mycobacteria], andWallemia sebiandEurotium amstelodami[filamentous fungi]) and are involved in HP. Our objectives were to determine the cross talk between MoDCs and HP-causative agents and to determine whether the resulting immune response varied according to the microbial extract tested. The phenotypic activation of MoDCs was measured by the increased expression of costimulatory molecules and levels of cytokines in supernatants. The functional activation of MoDCs was measured by the ability of MoDCs to induce lymphocytic proliferation and differentiation in a mixed lymphocytic reaction (MLR).E. amstelodami-exposed (EA) MoDCs expressed higher percentages of costimulatory molecules than didW. sebi-exposed (WS),S. rectivirgula-exposed (SR), orM. immunogenum-exposed (MI) MoDCs (P< 0.05, Wilcoxon signed-rank test). EA-MoDCs, WS-MoDCs, SR-MoDCs, and MI-MoDCs induced CD4+T cell proliferation and a Th1-polarized immune response. The present study provides evidence that, although differences were initially observed between MoDCs exposed to filamentous fungi and MoDCs exposed to bacteria, a Th1 response was ultimately promoted by DCs regardless of the microbial extract tested.

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Innate cell profiles during the acute and convalescent phase of SARS-CoV-2 infection in children

Nature Communications ◽

10.1038/s41467-021-21414-x ◽

2021 ◽

Vol 12 (1) ◽

Cited By ~ 6

Author(s):

Melanie R. Neeland ◽

Samantha Bannister ◽

Vanessa Clifford ◽

Kate Dohle ◽

Kim Mulholland ◽

...

Keyword(s):

Immune Response ◽

Dendritic Cells ◽

Immune Responses ◽

Acute Phase ◽

Innate Immune ◽

Low Density ◽

Innate Immune Responses ◽

Immunological Mechanisms ◽

Activated Neutrophils ◽

Classical Monocytes

AbstractChildren have mild severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) confirmed disease (COVID-19) compared to adults and the immunological mechanisms underlying this difference remain unclear. Here, we report acute and convalescent innate immune responses in 48 children and 70 adults infected with, or exposed to, SARS-CoV-2. We find clinically mild SARS-CoV-2 infection in children is characterised by reduced circulating subsets of monocytes (classical, intermediate, non-classical), dendritic cells and natural killer cells during the acute phase. In contrast, SARS-CoV-2-infected adults show reduced proportions of non-classical monocytes only. We also observe increased proportions of CD63+ activated neutrophils during the acute phase to SARS-CoV-2 in infected children. Children and adults exposed to SARS-CoV-2 but negative on PCR testing display increased proportions of low-density neutrophils that we observe up to 7 weeks post exposure. This study characterises the innate immune response during SARS-CoV-2 infection and household exposure in children.

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Failure To Recruit Anti-Inflammatory CD103+Dendritic Cells and a Diminished CD4+Foxp3+Regulatory T Cell Pool in Mice That Display Excessive Lung Inflammation and Increased Susceptibility to Mycobacterium tuberculosis

Infection and Immunity ◽

10.1128/iai.05552-11 ◽

2012 ◽

Vol 80 (3) ◽

pp. 1128-1139 ◽

Cited By ~ 46

Author(s):

Chaniya Leepiyasakulchai ◽

Lech Ignatowicz ◽

Andrzej Pawlowski ◽

Gunilla Källenius ◽

Markus Sköld

Keyword(s):

Immune Response ◽

Dendritic Cells ◽

Mycobacterium Tuberculosis ◽

T Cell ◽

Bacterial Growth ◽

Lung Inflammation ◽

Chronic Infection ◽

Host Immune Response ◽

Content Type ◽

Tnf Α

Susceptibility toMycobacterium tuberculosisis characterized by excessive lung inflammation, tissue damage, and failure to control bacterial growth. To increase our understanding of mechanisms that may regulate the host immune response in the lungs, we characterized dendritic cells expressing CD103 (αEintegrin) (αE-DCs) and CD4+Foxp3+regulatory T (Treg) cells duringM. tuberculosisinfection. In resistant C57BL/6 and BALB/c mice, the number of lung αE-DCs increased dramatically duringM. tuberculosisinfection. In contrast, highly susceptible DBA/2 mice failed to recruit αE-DCs even during chronic infection. Even though tumor necrosis factor alpha (TNF-α) is produced by multiple DCs and macrophage subsets and is required for control of bacterial growth, αE-DCs remained TNF-α negative. Instead, αE-DCs contained a high number of transforming growth factor beta-producing cells in infected mice. Further, we show that Tregcells in C57BL/6 and DBA/2 mice induce gamma interferon during pulmonary tuberculosis. In contrast to resistant mice, the Tregcell population was diminished in the lungs, but not in the draining pulmonary lymph nodes (PLN), of highly susceptible mice during chronic infection. Tregcells have been reported to inhibitM. tuberculosis-specific T cell immunity, leading to increased bacterial growth. Still, despite the reduced number of lung Tregcells in DBA/2 mice, the bacterial load in the lungs was increased compared to resistant animals. Our results show that αE-DCs and Tregcells that may regulate the host immune response are increased inM. tuberculosis-infected lungs of resistant mice but diminished in infected lungs of susceptible mice.

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