Search results for "Pertussis toxin"
showing 10 items of 26 documents
Muscarinic type-1 receptors contribute to I-K,I-ACh in human atrial cardiomyocytes and are upregulated in patients with chronic atrial fibrillation
2018
Background: Basal and acetylcholine-gated inward-rectifier K+-currents (I-K1 and I-K,I-ACh, respectively) are altered in atrial fibrillation (AF). G(i)-protein-coupled muscarinic (M) receptors type-2 are considered the predominant receptors activating I-K,I-ACh. Although a role for G(q)-coupled non-M-2-receptor subtypes has been suggested, the precise regulation of I-K,I-ACh by multiple M-receptor subtypes in the human atrium is unknown. Here, we investigated M-1-receptor-mediated I-K,I-ACh regulation and its remodeling in chronic AF (cAF). Methods and results: M-1-receptor mRNA and protein abundance were increased in atrial cardiomyocyte fractions and atrial homogenates from cAF patients, …
IL ‐1 signaling is critical for expansion but not generation of autoreactive GM ‐ CSF + Th17 cells
2016
Abstract Interleukin‐1 (IL‐1) is implicated in numerous pathologies, including multiple sclerosis and its animal model experimental autoimmune encephalomyelitis (EAE). However, the exact mechanism by which IL‐1 is involved in the generation of pathogenic T cells and in disease development remains largely unknown. We found that following EAE induction, pertussis toxin administration leads to IL‐1 receptor type 1 (IL‐1R1)‐dependent IL‐1β expression by myeloid cells in the draining lymph nodes. This myeloid‐derived IL‐1β did not vitally contribute to the generation and plasticity of Th17 cells, but rather promoted the expansion of a GM‐CSF + Th17 cell subset, thereby enhancing its encephalitog…
Evidence of increased circulation of Bordetella pertussis in the Italian adult population from seroprevalence data (2012–2013)
2016
Incidence data on pertussis cases in Italy do not show pertussis resurgence as recently described in other European countries. The aim of this study was to determine the seroprevalence of IgG antibodies to pertussis toxin (PT-IgG) in selected adult age groups, who can serve as a reservoir of Bordetella pertussis and be responsible for onward transmission to vulnerable infants. The seroprevalence of PT-IgG was studied in sera collected in 2012-2013 in three age groups: 20-29 years and 30-39 years (reproductive age), and ≥60 years. These data were compared to those from sera collected in similar age groups in 1996-1997. More than 80 % of the adult population analysed in the 2012-2013 group pr…
TSH/IGF-1 Receptor Cross-Talk Rapidly Activates Extracellular Signal-Regulated Kinases in Multiple Cell Types
2017
We previously showed that thyrotropin (TSH)/insulinlike growth factor (IGF)-1 receptor cross-talk appears to be involved in Graves’ orbitopathy (GO) pathogenesis and upregulation of thyroid-specific genes in human thyrocytes. In orbital fibroblasts from GO patients, coadministration of TSH and IGF-1 induces synergistic increases in hyaluronan secretion. In human thyrocytes, TSH plus IGF-1 synergistically increased expression of the sodium-iodide symporter that appeared to involve ERK1/2 activation. However, the details of ERK1/2 activation were not known, nor was whether ERK1/2 was involved in this synergism in other cell types. Using primary cultures of GO fibroblasts (GOFs) and human thyr…
Cellular Immunity in Adolescents and Adults following Acellular Pertussis Vaccine Administration
2007
ABSTRACT Cell-mediated immune (CMI) responses to an acellular pertussis vaccine administered to 49 subjects, a subset of participants in the National Institutes of Health-funded adult acellular pertussis vaccine efficacy trial, were evaluated and compared with antibody responses to vaccine antigens. Levels of proliferation of and cytokine secretion from lymphocytes cultured in the presence of pertussis toxin, filamentous hemagglutinin, or pertactin were measured before vaccination and 1 month and 1 year after vaccination. Statistically significant increases in lymphocyte stimulation indices and cytokine secretion were noted at both 1 month and 1 year after vaccination. Brisk pertussis antig…
Biphasic Erk1/2 activation sequentially involving Gs and Gi signaling is required in beta3-adrenergic receptor-induced primary smooth muscle cell pro…
2013
Abstract The beta3 adrenergic receptor (B3-AR) reportedly induces cell proliferation, but the signaling pathways that were proposed, involving either Gs or Gi coupling, remain controversial. To further investigate the role of G protein coupling in B3-AR induced proliferation, we stimulated primary human myometrial smooth muscle cells with SAR150640 (B3-AR agonist) in the absence or presence of variable G-protein inhibitors. Specific B3-AR stimulation led to an Erk1/2 induced proliferation. We observed that the proliferative effects of B3-AR require two Erk1/2 activation peaks (the first after 3 min, the second at 8 h). Erk1/2 activation at 3 min was mimicked by forskolin (adenylyl-cyclase a…
Pertussis-specific cell-mediated immunity in infants after vaccination with a tricomponent acellular pertussis vaccine.
1996
The aim of this study was to investigate pertussis-specific cell-mediated immunity in infants vaccinated with a tricomponent acellular vaccine. Infants were investigated during a primary vaccination schedule from the third month of life to the sixth month as well as before and after a booster at 15 to 24 months. This is the first report of specific cell-mediated immune responses to pertussis-related antigens in infants below the age of 12 months. Our data show that the vaccine induces T-cell responses specific for the vaccine components, detoxified pertussis toxin, filamentous hemagglutinin, and pertactin, that increase progressively over the course of the vaccination schedule. In contrast …
Analogous IgG subclass response to pertussis toxin in vaccinated children, healthy or affected by whooping cough
2003
The study of antigen specific IgG subclass distribution during disease, or during any other natural or artificial immunisation, can provide useful information on the kind of the immune response and the expected levels of protection. This is particularly true for diseases, such as pertussis in which the mechanisms underlying specific defence are still not completely understood. An investigation was therefore performed to evaluate the IgG subclass response to pertussis toxin (PT) in sera from 89 healthy vaccinated children and 131 vaccinated or unvaccinated children convalescent after a confirmed B. pertussis symptomatic infection. Antibody titres were expressed in arbitrary ELISA units/ml, a…
Comparative study of a whole-cell pertussis vaccine and a recombinant acellular pertussis vaccine.
1994
The safety and immunogenicity of an acellular pertussis vaccine containing the genetically detoxified pertussis toxin PT-9K/129C, filamentous hemagglutinin, and pertactin, together with diphtheria and tetanus toxoids, were compared with those of a whole-cell pertussis component-diphtheria-tetanus vaccine. Four hundred eighty infants were enrolled into this prospective, multicenter, double-blind study. Each infant was randomly given three doses of one of the two vaccines at 2, 4, and 6 months of age. Both local and systemic adverse reactions, reported within 48 hours and 7 days of each injection, were less frequent after the acellular vaccine than after the whole-cell vaccine. The enzyme-lin…
Holo-APP and G-protein-mediated signaling are required for sAPPa-induced activation of the Akt survival pathway
2014
International audience; Accumulating evidence indicates that loss of physiologic amyloid precursor protein (APP) function leads to reduced neuronal plasticity, diminished synaptic signaling and enhanced susceptibility of neurons to cellular stress during brain aging. Here we investigated the neuroprotective function of the soluble APP ectodomain sAPPa (soluble APPa), which is generated by cleavage of APP by a-secretase along the non-amyloidogenic pathway. Recombinant sAPPa protected primary hippocampal neurons and SH-SY5Y neuroblastoma cells from cell death induced by trophic factor deprivation. We show that this protective effect is abrogated in neurons from APP-knockout animals and APP-de…