Bordetella pertussis is the causative agent of whooping cough in humans, a disease that has recently experienced a resurgence. In contrast, Bordetella bronchiseptica infects the respiratory tract of various mammalian species, causing a range of symptoms from asymptomatic chronic carriage to acute illness. Both pathogens utilize type III secretion system (T3SS) to deliver the effector protein BteA into host cells. Once injected, BteA triggers a cascade of events leading to caspase 1-independent necrosis through a mechanism that remains incompletely understood. We demonstrate that BteA-induced cell death is characterized by the fragmentation of the cellular endoplasmic reticulum and mitochondria, the formation of necrotic balloon-like protrusions, and plasma membrane permeabilization. Importantly, genome-wide CRISPR-Cas9 screen targeting 19,050 genes failed to identify any host factors required for BteA cytotoxicity, suggesting that BteA does not require a single nonessential host factor for its cytotoxicity. We further reveal that BteA triggers a rapid and sustained influx of calcium ions, which is associated with organelle fragmentation and plasma membrane permeabilization. The sustained elevation of cytosolic Ca2+ levels results in mitochondrial calcium overload, mitochondrial swelling, cristolysis, and loss of mitochondrial membrane potential. Inhibition of calcium channels with 2-APB delays both the Ca2+ influx and BteA-induced cell death. Our findings indicate that BteA exploits essential host processes and/or redundant pathways to disrupt calcium homeostasis and mitochondrial function, ultimately leading to host cell death.IMPORTANCEThe respiratory pathogens Bordetella pertussis and Bordetella bronchiseptica exhibit cytotoxicity toward a variety of mammalian cells, which depends on the type III secretion effector BteA. Moreover, the increased virulence of B. bronchiseptica is associated with enhanced expression of T3SS and BteA. However, the molecular mechanism underlying BteA cytotoxicity is elusive. In this study, we performed a CRISPR-Cas9 screen, revealing that BteA-induced cell death depends on essential or redundant host processes. Additionally, we demonstrate that BteA disrupts calcium homeostasis, which leads to mitochondrial dysfunction and cell death. These findings contribute to closing the gap in our understanding of the signaling cascades targeted by BteA.

• MeSH
• bakteriální proteiny * metabolismus   genetika   MeSH
• Bordetella bronchiseptica genetika   metabolismus   účinky léků   MeSH
• Bordetella pertussis genetika   patogenita   metabolismus   účinky léků   MeSH
• buněčná smrt * účinky léků   MeSH
• endoplazmatické retikulum metabolismus   účinky léků   MeSH
• homeostáza * MeSH
• interakce hostitele a patogenu MeSH
• lidé MeSH
• mitochondrie metabolismus   účinky léků   MeSH
• sekreční systém typu III metabolismus   genetika   MeSH
• vápník * metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Pertussis, also known as whooping cough, is an acute respiratory illness primarily caused by Bordetella pertussis. Highly contagious, it poses significant morbidity and mortality risks, especially in infants. Despite widespread vaccination efforts, pertussis cases have recently resurged globally. This case report details possible complication in a 48-year-old woman, involving a cough-induced rib fracture and recurrent pneumothorax, highlighting the need for considering pertussis in patients with severe cough and back pain. CASE PRESENTATION: A 48-year-old female non-smoker with hypertension, treated with ACE inhibitor (perindopril), presented with a runny nose, productive cough, and back pain. Initial treatment for a common cold provided temporary relief. However, her symptoms worsened, and further examination revealed a fractured rib, pneumothorax, and subcutaneous emphysema. Laboratory tests confirmed elevated Bordetella pertussis toxin antibodies. She was treated with antibiotics, and despite recurrent symptoms, a conservative management approach was successful. Follow-up indicated resolution of symptoms, but significant anxiety related to her condition. CONCLUSION: This case emphasises the importance of considering pertussis in adults, as early symptoms resembling a common cold can lead to misdiagnosis. It also highlights the potential for significant musculoskeletal and pulmonary injuries due to intense coughing associated with pertussis. Prompt diagnosis and comprehensive management, including antibiotics and supportive care, are essential for favorable outcomes.

• MeSH
• antibakteriální látky terapeutické užití   MeSH
• Bordetella pertussis izolace a purifikace   MeSH
• fraktury žeber * komplikace   MeSH
• kašel etiologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• pertuse * komplikace   farmakoterapie   MeSH
• pneumotorax * etiologie   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

Černý kašel je vysoce nakažlivé bakteriální onemocnění postihující řasinkový epitel respiračního traktu. Jedná se o kapénkovou infekci, která se snadno šíří především v populaci vnímavých jedinců (novorozenci, kojenci). Onemocnění se projevuje záchvaty dráždivého kašle, v dětském věku a u rizikových skupin (senioři, imunosuprimovaní, osoby s chronickým onemocněním plic) může mít komplikovaný až fatální průběh. Před objevem vakcíny byla tato infekce častou příčinou kojenecké morbidity a mortality, v současnosti je v České republice vakcína proti pertusi součástí povinného očkování v kojeneckém věku. V rámci ochrany nejmenších dětí, jež jsou infekcí nejvíce ohroženy, je také doporučeno přeočkování těhotných žen ve 3. trimestru gravidity. Jelikož je v letošním roce počet hlášených případů pertuse opět na vzestupu, je vhodné si zopakovat základní informace o infekci a seznámit se s aktuálními doporučeními.

Whooping cough is a highly contagious bacterial disease that affects the ciliated epithelium of the respiratory tract. The disease is transmitted by the inhalation of infected droplets and easily spreads mainly in the population of responsive subjects (newborns, infants). The disease manifests by a paroxysmal unproductive cough, in childhood, and in a high-risk group of people (seniors, immunosuppressed patients, and patients with chronic lung disease) can have a complicated or fatal course. This infection was a frequent cause of infant morbidity and mortality before the development of the vaccine, in present the vaccine against pertussis is a part of mandatory vaccination in infant age in the Czech Republic. In protection of the smallest children, which are mostly threatened by whooping cough, is also recommended a revaccination during pregnancy between 27 and 36 weeks gestation. Cause of the increase in pertussis cases this year, it's good to repeat basic information about the infection and also get to know current recommendations.

• MeSH
• antibakteriální látky aplikace a dávkování   terapeutické užití   MeSH
• Bordetella pertussis patogenita   MeSH
• lidé MeSH
• pertuse * diagnóza   epidemiologie   farmakoterapie   MeSH
• pertusová vakcína MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• přehledy MeSH

BACKGROUND: Bordetella pertussis continues to cause whooping cough globally even in countries with high immunisation coverage. Booster vaccinations with acellular pertussis vaccines are thus used in children, adolescents, and adults. T cell immunity is crucial for orchestrating the immune response after vaccination. However, T cell assays can be expensive and difficult to implement in large clinical trials. In this study, a whole blood (WB) stimulation assay was developed to identify secreted T cell associated cytokines in different age groups after acellular pertussis booster vaccination. MATERIAL AND METHODS: Longitudinal WB samples were collected from a small set of subjects (n = 38) aged 7-70 years participating in a larger ongoing clinical trial. For assay development, samples were diluted and incubated with purified inactivated pertussis toxin (PT), filamentous haemagglutinin (FHA), inactivated B. pertussis lysate, and complete medium (M) as stimulating conditions, with anti-CD28 and anti-CD49d as co-stimulants. Different timepoints around the vaccination (D0, D7, D14, D28), WB dilution factor (1:2, 1:4) and incubation time (24 h, 48 h, 72 h) were compared. Responses to 15 cytokines were tested with Luminex/multiplex immunoassay. RESULTS: The optimized assay consisted of WB incubation with M, PT, and FHA (including the two co-stimulants). After 48 h incubation, supernatants were collected for measurement of seven selected T cell associated cytokines (IL-2, IL-5, IL-10, IL-13, IL-17 A, IL-17F, and IFN-y) from samples before and 28 days after vaccination. PT stimulation showed a trend for upregulation of IL-2, IL-13, and IL-17 A/F for adult subjects, whereas the responses of all cytokines were downregulated for the paediatric subjects. Furthermore, PT and FHA-stimulated WB showed diverse cytokine producing profiles. CONCLUSIONS: The developed WB-based cytokine assay was shown to be less costly, easy to perform, and functional in differently aged individuals. Further, it requires only a small amount of fresh blood, which is beneficial especially for studies including infants. Our results support the use of this assay for other immunological studies in the future.

• MeSH
• antigeny bakteriální * imunologie   MeSH
• Bordetella pertussis * imunologie   MeSH
• cytokiny * krev   imunologie   MeSH
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• pertuse * imunologie   krev   prevence a kontrola   MeSH
• pertusová vakcína * imunologie   aplikace a dávkování   MeSH
• sekundární imunizace MeSH
• senioři MeSH
• T-lymfocyty * imunologie   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Bordetella pertussis infects the upper airways of humans and disarms host defense by the potent immuno-subversive activities of its pertussis (PT) and adenylate cyclase (CyaA) toxins. CyaA action near-instantly ablates the bactericidal activities of sentinel CR3-expressing myeloid phagocytes by hijacking cellular signaling pathways through the unregulated production of cAMP. Moreover, CyaA-elicited cAMP signaling also inhibits the macrophage colony-stimulating factor (M-CSF)-induced differentiation of incoming inflammatory monocytes into bactericidal macrophages. We show that CyaA/cAMP signaling via protein kinase A (PKA) downregulates the M-CSF-elicited expression of monocyte receptors for transferrin (CD71) and hemoglobin-haptoglobin (CD163), as well as the expression of heme oxygenase-1 (HO-1) involved in iron liberation from internalized heme. The impact of CyaA action on CD71 and CD163 levels in differentiating monocytes is largely alleviated by the histone deacetylase inhibitor trichostatin A (TSA), indicating that CyaA/cAMP signaling triggers epigenetic silencing of genes for micronutrient acquisition receptors. These results suggest a new mechanism by which B. pertussis evades host sentinel phagocytes to achieve proliferation on airway mucosa.IMPORTANCETo establish a productive infection of the nasopharyngeal mucosa and proliferate to sufficiently high numbers that trigger rhinitis and aerosol-mediated transmission, the pertussis agent Bordetella pertussis deploys several immunosuppressive protein toxins that compromise the sentinel functions of mucosa patrolling phagocytes. We show that cAMP signaling elicited by very low concentrations (22 pM) of Bordetella adenylate cyclase toxin downregulates the iron acquisition systems of CD14+ monocytes. The resulting iron deprivation of iron, a key micronutrient, then represents an additional aspect of CyaA toxin action involved in the inhibition of differentiation of monocytes into the enlarged bactericidal macrophage cells. This corroborates the newly discovered paradigm of host defense evasion mechanisms employed by bacterial pathogens, where manipulation of cellular cAMP levels blocks monocyte to macrophage transition and replenishment of exhausted phagocytes, thereby contributing to the formation of a safe niche for pathogen proliferation and dissemination.

• MeSH
• adenylátcyklasový toxin * metabolismus   genetika   MeSH
• AMP cyklický * metabolismus   MeSH
• antigeny diferenciační myelomonocytární MeSH
• Bordetella pertussis * MeSH
• buněčná diferenciace * MeSH
• CD antigeny metabolismus   genetika   MeSH
• lidé MeSH
• lipopolysacharidové receptory * metabolismus   MeSH
• monocyty * metabolismus   imunologie   mikrobiologie   MeSH
• proteinkinasy závislé na cyklickém AMP metabolismus   MeSH
• receptory buněčného povrchu metabolismus   genetika   MeSH
• signální transdukce * MeSH
• upregulace MeSH
• železo metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

• MeSH
• antibakteriální látky aplikace a dávkování   terapeutické užití   MeSH
• antibiotická profylaxe MeSH
• Bordetella pertussis izolace a purifikace   MeSH
• hlášení nemocí MeSH
• lidé MeSH
• makrolidy aplikace a dávkování   terapeutické užití   MeSH
• pertuse * diagnóza   farmakoterapie   prevence a kontrola   MeSH
• polymerázová řetězová reakce MeSH
• vakcinace MeSH
• Check Tag
• lidé MeSH

• MeSH
• Bordetella pertussis izolace a purifikace   MeSH
• dítě MeSH
• epidemický výskyt choroby * MeSH
• kojenec MeSH
• lidé MeSH
• pertuse * epidemiologie   prevence a kontrola   MeSH
• pertusová vakcína aplikace a dávkování   MeSH
• předškolní dítě MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• dopisy MeSH
• Geografické názvy
• Česká republika MeSH

• MeSH
• Bordetella pertussis MeSH
• lidé MeSH
• pertuse * epidemiologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH

INTRODUCTION: Tuberculosis (TB) remains the first cause of death from infection caused by a bacterial pathogen. Chemotherapy does not eradicate Mycobacterium tuberculosis (Mtb) from human lungs, and the pathogen causes a latent tuberculosis infection that cannot be prevented by the currently available Bacille Calmette Guerin (BCG) vaccine, which is ineffective in the prevention of pulmonary TB in adults. HLA-E-restricted CD8+ T lymphocytes are essential players in protective immune responses against Mtb. Hence, expanding this population in vivo or ex vivo may be crucial for vaccination or immunotherapy against TB. METHODS: The enzymatically inactive Bordetella pertussis adenylate cyclase (CyaA) toxoid is an effective tool for delivering peptide epitopes into the cytosol of antigen-presenting cells (APC) for presentation and stimulation of specific CD8+ T-cell responses. In this study, we have investigated the capacity of the CyaA toxoid to deliver Mtb epitopes known to bind HLA-E for the expansion of human CD8+ T cells in vitro. RESULTS: Our results show that the CyaA-toxoid containing five HLA-E-restricted Mtb epitopes causes significant expansion of HLA-E-restricted antigen-specific CD8+ T cells, which produce IFN-γ and exert significant cytotoxic activity towards peptide-pulsed macrophages. DISCUSSION: HLA-E represents a promising platform for the development of new vaccines; our study indicates that the CyaA construct represents a suitable delivery system of the HLA-E-binding Mtb epitopes for ex vivo and in vitro expansion of HLA-E-restricted CD8+ T cells inducing a predominant Tc1 cytokine profile with a significant increase of IFN-γ production, for prophylactic and immunotherapeutic applications against Mtb.

• MeSH
• adenylátcyklasy MeSH
• antigeny HLA-E MeSH
• Bordetella pertussis MeSH
• CD8-pozitivní T-lymfocyty MeSH
• epitopy MeSH
• lidé MeSH
• MHC antigeny I. třídy MeSH
• Mycobacterium tuberculosis * MeSH
• peptidy MeSH
• toxoidy MeSH
• tuberkulóza * prevence a kontrola   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Bordetella pertussis is a Gram-negative, strictly human re-emerging respiratory pathogen and the causative agent of whooping cough. Similar to other Gram-negative pathogens, B. pertussis produces the type III secretion system, but its role in the pathogenesis of B. pertussis is enigmatic and yet to be elucidated. Here, we combined RNA-seq, LC-MS/MS, and co-immunoprecipitation techniques to identify and characterize the novel CesT family T3SS chaperone BP2265. We show that this chaperone specifically interacts with the secreted T3SS regulator BtrA and represents the first non-flagellar chaperone required for the secretion of an anti-sigma factor. In its absence, secretion but not production of BtrA and most T3SS substrates is severely impaired. It appears that the role of BtrA in regulating T3SS extends beyond its activity as an antagonist of the sigma factor BtrS. Predictions made by artificial intelligence system AlphaFold support the chaperone function of BP2265 towards BtrA and outline the structural basis for the interaction of BtrA with its target BtrS. We propose to rename BP2265 to BtcB for the Bordetella type III chaperone of BtrA.In addition, the absence of the BtcB chaperone results in increased expression of numerous flagellar genes and several virulence genes. While increased production of flagellar proteins and intimin BipA translated into increased biofilm formation by the mutant, enhanced production of virulence factors resulted in increased cytotoxicity towards human macrophages. We hypothesize that these phenotypic traits result indirectly from impaired secretion of BtrA and altered activity of the BtrA/BtrS regulatory node.

• MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• Bordetella pertussis * metabolismus   MeSH
• chromatografie kapalinová MeSH
• lidé MeSH
• pertuse * MeSH
• regulace genové exprese u bakterií MeSH
• sigma faktor genetika   MeSH
• tandemová hmotnostní spektrometrie MeSH
• umělá inteligence MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH