In Glässer's disease outbreaks, Glaesserella (Haemophilus) parasuis has to overcome the non-specific immune system in the lower respiratory tract, the alveolar macrophages. Here we showed that porcine alveolar macrophages (PAMs) were able to recognize and phagocyte G. parasuis with strain-to-strain variability despite the presence of the capsule in virulent (serovar 1, 5, 12) as well in avirulent strains (serovar 6 and 9). The capsule, outer membrane proteins, virulence-associated autotransporters, cytolethal distending toxins and many other proteins have been identified as virulence factors of this bacterium. Therefore, we immunized pigs with the crude capsular extract (cCE) from the virulent G. parasuis CAPM 6475 strain (serovar 5) and evaluated the role of the anti-cCE/post-vaccinal IgG in the immune response of PAMs to in vitro infection with various G. parasuis strains. We demonstrated the specific binding of the antibodies to the cCE by Western-blotting assay and immunoprecipitation as well as the specific binding to the strain CAPM 6475 in transmission electron microscopy. In the cCE, we identified several virulence-associated proteins that were immunoreactive with IgG isolated from sera of immunized pigs. Opsonization of G. parasuis strains by post-vaccinal IgG led to enhanced phagocytosis of G. parasuis by PAMs at the first two hours of infection. Moreover, opsonization increased the oxidative burst and expression/production of both pro- and anti-inflammatory cytokines. The neutralizing effects of these antibodies on the antioxidant mechanisms of G. parasuis may lead to attenuation of its virulence and pathogenicity in vivo. Together with opsonization of bacteria by these antibodies, the host may eliminate G. parasuis in the infection site more efficiently. Based on these results, the crude capsular extract is a vaccine candidate with immunogenic properties.
- MeSH
- alveolární makrofágy imunologie metabolismus mikrobiologie MeSH
- antigeny bakteriální imunologie MeSH
- bakteriální pouzdra imunologie MeSH
- fagocytóza MeSH
- Haemophilus parasuis imunologie patogenita MeSH
- hemofilové infekce imunologie metabolismus mikrobiologie MeSH
- kinetika MeSH
- kultivované buňky MeSH
- neutralizující protilátky imunologie metabolismus MeSH
- protilátky bakteriální imunologie metabolismus MeSH
- reaktivní formy kyslíku metabolismus MeSH
- séroskupina MeSH
- specificita protilátek MeSH
- Sus scrofa MeSH
- virulence MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The inhalation of metal (including lead) nanoparticles poses a real health issue to people and animals living in polluted and/or industrial areas. In this study, we exposed mice to lead(II) nitrate nanoparticles [Pb(NO3)2 NPs], which represent a highly soluble form of lead, by inhalation. We aimed to uncover the effects of their exposure on individual target organs and to reveal potential variability in the lead clearance. We examined (i) lead biodistribution in target organs using laser ablation and inductively coupled plasma mass spectrometry (LA-ICP-MS) and atomic absorption spectrometry (AAS), (ii) lead effect on histopathological changes and immune cells response in secondary target organs and (iii) the clearance ability of target organs. In the lungs and liver, Pb(NO3)2 NP inhalation induced serious structural changes and their damage was present even after a 5-week clearance period despite the lead having been almost completely eliminated from the tissues. The numbers of macrophages significantly decreased after 11-week Pb(NO3)2 NP inhalation; conversely, abundance of alpha-smooth muscle actin (α-SMA)-positive cells, which are responsible for augmented collagen production, increased in both tissues. Moreover, the expression of nuclear factor κB (NF-κB) and selected cytokines, such as tumor necrosis factor alpha (TNFα), transforming growth factor beta 1 (TGFβ1), interleukin 6(IL-6), IL-1α and IL-1β , displayed a tissue-specific response to lead exposure. In summary, diminished inflammatory response in tissues after Pb(NO3)2 NPs inhalation was associated with prolonged negative effect of lead on tissues, as demonstrated by sustained pathological changes in target organs, even after long clearance period.
- MeSH
- aktiny agonisté genetika imunologie MeSH
- alveolární makrofágy účinky léků imunologie patologie MeSH
- aplikace inhalační MeSH
- biologická dostupnost MeSH
- dusičnany farmakokinetika toxicita MeSH
- exprese genu MeSH
- inhalační expozice analýza MeSH
- interleukin-1alfa agonisté genetika imunologie MeSH
- interleukin-1beta agonisté genetika imunologie MeSH
- interleukin-6 agonisté genetika imunologie MeSH
- játra účinky léků imunologie patologie MeSH
- kovové nanočástice aplikace a dávkování toxicita MeSH
- látky znečišťující vzduch farmakokinetika toxicita MeSH
- myši inbrední ICR MeSH
- myši MeSH
- NF-kappa B agonisté genetika imunologie MeSH
- olovo farmakokinetika toxicita MeSH
- plíce účinky léků imunologie patologie MeSH
- poločas MeSH
- spektrofotometrie atomová MeSH
- tkáňová distribuce MeSH
- TNF-alfa agonisté genetika imunologie MeSH
- transformující růstový faktor beta1 agonisté genetika imunologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Circulating inflammatory monocytes are attracted to infected mucosa and differentiate into macrophage or dendritic cells endowed with enhanced bactericidal and antigen presenting capacities. In this brief Perspective we discuss the newly emerging insight into how the cAMP signaling capacity of Bordetella pertussis adenylate cyclase toxin manipulates the differentiation of monocytes and trigger dedifferentiation of the alveolar macrophages to facilitate bacterial colonization of human airways.
- MeSH
- adenylátcyklasový toxin farmakologie fyziologie MeSH
- alveolární makrofágy cytologie účinky léků MeSH
- AMP cyklický fyziologie MeSH
- biologické modely MeSH
- Bordetella pertussis fyziologie MeSH
- buněčná diferenciace MeSH
- dediferenciace buněk účinky léků MeSH
- dýchací soustava účinky léků imunologie mikrobiologie MeSH
- fagocytóza MeSH
- interakce hostitele a patogenu imunologie MeSH
- lidé MeSH
- monocyty cytologie účinky léků MeSH
- myši MeSH
- prezentace antigenu účinky léků MeSH
- přirozená imunita účinky léků MeSH
- slizniční imunita účinky léků MeSH
- systémy druhého messengeru účinky léků fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
In vitro three-dimensional (3D) lung cell models have been thoroughly investigated in recent years and provide a reliable tool to assess the hazard associated with nanomaterials (NMs) released into the air. In this study, a 3D lung co-culture model was optimized to assess the hazard potential of multiwalled carbon nanotubes (MWCNTs), which is known to provoke inflammation and fibrosis, critical adverse outcomes linked to acute and prolonged NM exposure. The lung co-cultures were exposed to MWCNTs at the air-liquid interface (ALI) using the VITROCELL® Cloud system while considering realistic occupational exposure doses. The co-culture model was composed of three human cell lines: alveolar epithelial cells (A549), fibroblasts (MRC-5), and macrophages (differentiated THP-1). The model was exposed to two types of MWCNTs (Mitsui-7 and Nanocyl) at different concentrations (2-10 μg/cm2) to assess the proinflammatory as well as the profibrotic responses after acute (24 h, one exposure) and prolonged (96 h, repeated exposures) exposure cycles. The results showed that acute or prolonged exposure to different concentrations of the tested MWCNTs did not induce cytotoxicity or apparent profibrotic response; however, suggested the onset of proinflammatory response.
- MeSH
- aerosoly MeSH
- alveolární makrofágy metabolismus patologie MeSH
- biologické modely * MeSH
- buňky A549 MeSH
- fibroblasty metabolismus patologie MeSH
- lidé MeSH
- nanotrubičky uhlíkové škodlivé účinky MeSH
- pneumocyty metabolismus patologie MeSH
- THP-1 buňky MeSH
- zánět chemicky indukované metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Monocytes arriving at the site of infection differentiate into functional effector macrophages to replenish the resident sentinel cells. Bordetella pertussis, the pertussis agent, secretes an adenylate cyclase toxin-hemolysin (CyaA) that binds myeloid phagocytes through complement receptor 3 (CD11b/CD18) and swiftly delivers its adenylyl cyclase enzyme domain into phagocytes. This ablates the bactericidal capacities of phagocytes through massive and unregulated conversion of cytosolic ATP into the key signaling molecule cAMP. We show that exposure of primary human monocytes to as low a concentration as 22.5 pM CyaA, or a low (2:1) multiplicity of infection by CyaA-producing B. pertussis bacteria, blocks macrophage colony-stimulating factor (M-CSF)-driven differentiation of monocytes. CyaA-induced cAMP signaling mediated through the activity of protein kinase A (PKA) efficiently blocked expression of macrophage markers, and the monocytes exposed to 22.5 pM CyaA failed to acquire the characteristic intracellular complexity of mature macrophage cells. Neither M-CSF-induced endoplasmic reticulum (ER) expansion nor accumulation of Golgi bodies, mitochondria, or lysosomes was observed in toxin-exposed monocytes, which remained small and poorly phagocytic and lacked pseudopodia. Exposure to 22.5 pM CyaA toxin provoked loss of macrophage marker expression on in vitro differentiated macrophages, as well as on primary human alveolar macrophages, which appeared to dedifferentiate into monocyte-like cells with upregulated CD14 levels. This is the first report that terminally differentiated tissue-resident macrophage cells can be dedifferentiated in vitro The results suggest that blocking of monocyte-to-macrophage transition and/or dedifferentiation of the sentinel cells of innate immunity through cAMP-elevating toxin action may represent a novel immune evasion strategy of bacterial pathogens.IMPORTANCE Macrophages are key sentinel cells of the immune system, and, as such, they are targeted by the toxins produced by the pertussis agent Bordetella pertussis The adenylate cyclase toxin (CyaA) mediates immune evasion of B. pertussis by suspending the bactericidal activities of myeloid phagocytes. We reveal a novel mechanism of potential subversion of host immunity, where CyaA at very low (22 pM) concentrations could inhibit maturation of human monocyte precursors into the more phagocytic macrophage cells. Furthermore, exposure to low CyaA amounts has been shown to trigger dedifferentiation of mature primary human alveolar macrophages back into monocyte-like cells. This unprecedented capacity is likely to promote survival of the pathogen in the airways, both by preventing maturation of monocytes attracted to the site of infection into phagocytic macrophages and by dedifferentiation of the already airway-resident sentinel cells.
- MeSH
- adenylátcyklasový toxin škodlivé účinky metabolismus MeSH
- alveolární makrofágy účinky léků metabolismus MeSH
- Bordetella pertussis chemie MeSH
- buněčná diferenciace účinky léků MeSH
- interakce hostitele a patogenu MeSH
- lidé MeSH
- monocyty účinky léků metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
AIMS: To elucidate the role of alveolar macrophages (AM) in the pathogenesis of hypoxic pulmonary hypertension (HPH), we tested the effects of sustained hypoxia on AM polarization and on the formation of superoxide by AM in vivo and in vitro. MAIN METHODS: Rat AM were obtained by bronchoalveolar lavage. 4-day exposure to hypoxia (10% O2) was carried out in vivo (rats in isobaric hypoxic chamber, controls kept in air) or in vitro (control AM in 21% O2 and 5% CO2). Superoxide production was measured by luminol-orthovanadate chemiluminescence, AM polarization was detected immunocytochemically. To ascertain the effect of substances contained in the alveolar environment, we cultivated cells also in the presence of non-cellular components of the bronchoalveolar lavage fluid (BALF) either from controls or from rats exposed to 4 days of hypoxia. KEY FINDINGS: In vivo, but not in vitro, hypoxia increased AM superoxide production. Both types of hypoxia polarized AM into M2 (pro-proliferative) type. While the presence of control BALF attenuated superoxide production in AM cultivated in normoxia, BALF from the hypoxia-exposed rats had no effect. In AM cultivated in hypoxia, superoxide production was not altered by control BALF and elevated by BALF obtained from hypoxic rats. SIGNIFICANCE: Hypoxia does not influence superoxide production by AM directly but rather by modulating their milieu and their sensitivity to external influences.
- MeSH
- alveolární makrofágy metabolismus patologie MeSH
- bronchoalveolární lavážní tekutina chemie MeSH
- hypoxie patofyziologie MeSH
- krysa rodu rattus MeSH
- kultivované buňky MeSH
- potkani Wistar MeSH
- superoxidy metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Macrophage cells are present in high abundance in the lung to intercept invading microorganisms that gain access through airway mucosal surfaces. Several bacterial pathogens have evolved the capacity to evade the innate immune response by establishing infections within pulmonary macrophages upon phagocytosis, leading to prolonged disease. Macrolide antibiotics such as azithromycin and clarithromycin accumulate in phagocytic cells and have been shown to preferentially distribute in tissues where populations of these cells reside. We employed this class of molecules as targeting ligands to direct virus-like particles (VLPs) to lung-resident macrophages. VLP-macrolide conjugates showed enhanced uptake into RAW 264.7 macrophage cells in culture, with azithromycin displaying the greatest effect; distinct differences were also observed for different macrocycle structures and orientations on the particle surface. Activation of macrophage cells was stimulated by particle uptake toward an intermediate activation state, in contrast to previous reports using macrolide-functionalized gold nanorods that stimulated a cytotoxic macrophage response. Attached azithromycin was also able to direct VLPs to the lungs in mice, with significant accumulation within 2 h of systemic injection. These results suggest that this new class of bioconjugate could serve as an effective platform for intracellular drug delivery in the context of pulmonary infections.
- MeSH
- Allolevivirus chemie MeSH
- alveolární makrofágy metabolismus MeSH
- antibakteriální látky chemie farmakokinetika MeSH
- azithromycin chemie farmakokinetika MeSH
- cytokiny metabolismus MeSH
- Escherichia coli genetika MeSH
- fagocytóza MeSH
- fenotyp MeSH
- klarithromycin chemie farmakokinetika MeSH
- myši MeSH
- plíce účinky léků metabolismus MeSH
- příprava léků metody MeSH
- RAW 264.7 buňky MeSH
- systémy cílené aplikace léků metody MeSH
- tkáňová distribuce MeSH
- virové plášťové proteiny chemie farmakokinetika MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Bordetellae, pathogenic to mammals, produce an immunomodulatory adenylate cyclase toxin-hemolysin (CyaA, ACT or AC-Hly) that enables them to overcome the innate immune defense of the host. CyaA subverts host phagocytic cells by an orchestrated action of its functional domains, where an extremely catalytically active adenylyl cyclase enzyme is delivered into phagocyte cytosol by a pore-forming repeat-in-toxin (RTX) cytolysin moiety. By targeting sentinel cells expressing the complement receptor 3, known as the CD11b/CD18 (αMβ₂) integrin, CyaA compromises the bactericidal functions of host phagocytes and supports infection of host airways by Bordetellae. Here, we review the state of knowledge on structural and functional aspects of CyaA toxin action, placing particular emphasis on signaling mechanisms by which the toxin-produced 3',5'-cyclic adenosine monophosphate (cAMP) subverts the physiology of phagocytic cells.
- MeSH
- adenylátcyklasový toxin chemie MeSH
- alveolární makrofágy cytologie MeSH
- AMP cyklický chemie MeSH
- Bordetella pertussis MeSH
- dendritické buňky cytologie MeSH
- fagocyty chemie MeSH
- kinasa Syk MeSH
- lidé MeSH
- makrofágový antigen 1 MeSH
- neutrofily cytologie MeSH
- proteinové domény MeSH
- signální transdukce * MeSH
- terciární struktura proteinů MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Epidermolysis bullosa a Bartov syndróm sú pomerne presne histopatologicky dokumentované ochorenia. V príspevku autori približujú zaujímavý a doteraz neopísaný úkaz v pľúcach dieťaťa mužského pohlavia s epidermolysis bullosa junctionalis a s Bartovým syndrómom, ktoré zomrelo po 17 dňoch od narodenia a 13 dňoch od vykonania operácie pre atréziu pylora na multiorgánové zlyhanie pri základných vrodených ochoreniach. Pri histologickom vyšetrení sa v alveolách pľúc našli okrem masívnej prítomnosti penovitých makrofágov aj početné globoidné útvary pripomínajúce morfologicky aj imunohistochemicky Hassallove telieska v týmuse novorodenca. Išlo o acidofilné sférické telieska s koncentrickou skladbou, vo väzivovom tkanive s fokálnou prítomnosťou fibrínu a s ojedinelým dôkazom cytokeratínu AE1/AE3 a cytokeratínu HMW pozitívnych epitélií a s CD68 pozitívnymi histiocytovými elementmi, ktoré autori pracovne nazvali „hassalloidnými“ telieskami. Zaujímavým nálezom bola aj folikulárna kožná štruktúra v centre „hassalloidného“ telieska, ktorá svedčí o aspirácii súčasti kože počas intrauterinného života. Normálne Apgarovej skóre pri narodení dieťaťa (10/10/10 b.) a závažný histomorfologický nález pri úmrtí dieťaťa najskôr svedčia o patogenetickej formácii „hassalloidných“ teliesok v pľúcach počas 17-dňového života postihnutého dieťaťa.
Epidermolysis bullosa and Bart´s syndrome are fairly accurately documented diseases by histopathology. In the article the authors describe interesting and hitherto undescribed phenomenon in the lungs male infant with epidermolysis bullosa junctionalis and Bart‘s syndrome, who died 17 days after birth and 13 days after surgery for pyloric atresia, on multiorgan failure within basic congenital diseases. Histologically in lung alveoli was found to the massive presence of foamy macrophages and numerous globoid formations resembling morphological and immunohistochemical „Hassall´s” bodies in a thymus of the newborn. It was a acidophillic spherical bodies concentric tracks in the connective tissue with focal presence of fibrin, as a unique proof CKAE1/AE3 and CKHMW positive epithelial cells and CD68-positive histiocytic elements. An interesting finding was the follicular skin structure in the center „hassalloid´s-like” body, which suggests an aspiration components of the skin during intrauterine life. Normal Apgar score at birth of the child (10/10/10 s.) and severe histological features on the death of the child testify for the first pathogenetic formation „hassalloid´s-like” bodies in the lungs during the 17-day life of a disabled child.
- Klíčová slova
- Bartův syndrom, pěnovité makrofágy, Hassallova tělíska,
- MeSH
- alveolární makrofágy * patologie MeSH
- epidermolysis bullosa junkční * MeSH
- kožní nemoci MeSH
- lidé MeSH
- novorozenec MeSH
- pitva MeSH
- plíce patologie MeSH
- plicní alveoly * patologie MeSH
- syndrom MeSH
- thymus MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- Publikační typ
- kazuistiky MeSH
Exposure to hypoxia, leading to hypoxic pulmonary hypertension (HPH), is associated with activation of alveolar macrophages (AM). However, it remains unclear how AM participate in this process. There are studies which imply that the AM product monocyte chemoattractant protein-1 (MCP-1) plays an important role. Thus we tested: 1. if the selective elimination of AM attenuates HPH in rats, 2. the correlation of MCP-1 plasmatic concentrations with the presence and absence of AM during exposure to hypoxia, 3. the direct influence of hypoxia on MCP-1 production in isolated AM. We found that experimental depletion of AM attenuated the chronic hypoxia-induced increase in mean pulmonary arterial pressure, but did not affect the serum MCP-1 concentrations. Furthermore, the MCP-1 production by AM in vitro was unaffected by hypoxia. Thus we conclude that AM play a significant role in the mechanism of HPH, but MCP-1 release from these cells is most likely not involved in this process. The increase of MCP-1 accompanying the development of HPH probably originates from other sources than AM.
- MeSH
- alveolární makrofágy sekrece MeSH
- chemokin CCL2 krev MeSH
- dichlormethylendifosfonát terapeutické užití MeSH
- hypoxie komplikace MeSH
- plicní hypertenze imunologie prevence a kontrola MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH