Search results for "secretion"

Rhythmicity of Intestinal IgA Responses Confers Oscillatory Commensal Microbiota Mutualism

2021

ABSTRACTMutualistic interactions with the commensal microbiota are enforced through a range of immune responses that confer metabolic benefits for the host and ensure tissue health and homeostasis. Immunoglobulin (Ig)A responses directly determine the composition of commensal species that colonize the intestinal tract but require significant metabolic resources to fuel antibody production by tissue-resident plasma cells. Here we demonstrate IgA responses are subject to diurnal regulation by dietary-derived metabolic cues and a cell-intrinsic circadian clock. Rhythmicity in IgA secretion conferred oscillatory patterns on the commensal microbial community and its associated metabolic activity…

Molecular surveillance of norovirus, 2005–16 : an epidemiological analysis of data collected from the NoroNet network

2018

BACKGROUND: The development of a vaccine for norovirus requires a detailed understanding of global genetic diversity of noroviruses. We analysed their epidemiology and diversity using surveillance data from the NoroNet network.METHODS: We included genetic sequences of norovirus specimens obtained from outbreak investigations and sporadic gastroenteritis cases between 2005 and 2016 in Europe, Asia, Oceania, and Africa. We genotyped norovirus sequences and analysed sequences that overlapped at open reading frame (ORF) 1 and ORF2. Additionally, we assessed the sampling date and country of origin of the first reported sequence to assess when and where novel drift variants originated.FINDINGS: W…

Selective targeting of collagen IV in the cancer cell microenvironment reduces tumor burden

2018

Goodpasture antigen-binding protein (GPBP) is an exportable1 Ser/Thr kinase that induces collagen IV expansion and has been associated with chemoresistance following epithelial-to-mesenchymal transition (EMT). Here we demonstrate that cancer EMT phenotypes secrete GPBP (mesenchymal GPBP) which displays a predominant multimeric oligomerization and directs the formation of previously unrecognized mesh collagen IV networks (mesenchymal collagen IV). Yeast two-hybrid (YTH) system was used to identify a 260SHCIE264 motif critical for multimeric GPBP assembly which then facilitated design of a series of potential peptidomimetics. The compound 3-[4''-methoxy-3,2'-dimethyl-(1,1';4',1'')terphenyl-2'…

Serum VEGF and b-FGF profiles after tension-free or conventional hernioplasty.

2005

Angiogenesis is strongly influenced by vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (b-FGF), whose production is also regulated by interferon (IFN)-gamma and interleukin (IL)-10. The aim of this study was to evaluate the modifications of serum VEGF, b-FGF, IFN-gamma and IL-10 levels in patients with inguinal hernia undergoing hernioplasty with the Lichtenstein technique (LH) using polypropylene mesh or with Bassini open conventional inguinal hernia repair (BH). MATERIALS AND METHODS: Randomly, 16 patients underwent BH, and 16 were treated with the LH technique using polypropylene mesh. Blood samples were collected 24 h prior to surgery and then 6, 24, 48 and …

Perioperative nonspecific histamine release : a new classification by aetiological mechanisms and evaluation of their clinical relevance

1993

As a consequence of the performance of a randomized controlled clinical trial on perioperative histamine release and cardiovascular and respiratory disturbances, several types of increases in plasma histamine had to be distinguished instead of only two which existed at the beginning of the study: drug-induced allergic and pseudoallergic reactions. First of all, the new classification by aetiology (clinical epidemiology) was derived from a meta-analysis (secondary analysis) of the most recent literature. According to that histamine release in the perioperative period has several, different causes and is involved in several, different disease manifestations. A clear distinction (classificatio…

Tumor-derived lactic acid modulates dendritic cell activation and antigen expression.

2005

The tumor milieu can influence dendritic cell (DC) differentiation. We analyzed DC differentiation in a 3-dimensional tumor model and propose a new mechanism of DC modulation by the tumor environment. Monocytes were cultured in the presence of IL-4 and GM-CSF within multicellular tumor spheroids (MCTSs) generated from different tumor cell lines. Monocytes invaded the MCTSs and differentiated into tumor-associated dendritic cells (TADCs). The antigen expression was altered on TADCs independent of the culture conditions (immature/mature DCs, Langerhans cells) and IL-12 secretion was reduced. Supernatants of MCTSs could partially transfer the suppressive effect. Conditioned media from urotheli…

Extracellular vesicles from parasitic helminths contain specific excretory/secretory proteins and are internalized in intestinal host cells.

2012

The study of host-parasite interactions has increased considerably in the last decades, with many studies focusing on the identification of parasite molecules (i.e. surface or excretory/secretory proteins (ESP)) as potential targets for new specific treatments and/or diagnostic tools. In parallel, in the last few years there have been significant advances in the field of extracellular vesicles research. Among these vesicles, exosomes of endocytic origin, with a characteristic size ranging from 30-100 nm, carry several atypical secreted proteins in different organisms, including parasitic protozoa. Here, we present experimental evidence for the existence of exosome-like vesicles in parasitic…

AMPA receptor GluA2 subunit defects are a cause of neurodevelopmental disorders.

2019

AMPA receptors (AMPARs) are tetrameric ligand-gated channels made up of combinations of GluA1-4 subunits encoded by GRIA1-4 genes. GluA2 has an especially important role because, following post-transcriptional editing at the Q607 site, it renders heteromultimeric AMPARs Ca2+-impermeable, with a linear relationship between current and trans-membrane voltage. Here, we report heterozygous de novo GRIA2 mutations in 28 unrelated patients with intellectual disability (ID) and neurodevelopmental abnormalities including autism spectrum disorder (ASD), Rett syndrome-like features, and seizures or developmental epileptic encephalopathy (DEE). In functional expression studies, mutations lead to a dec…

P4–286: Secretion of the soluble APP ectodomain (APPS) is not affected by the non–steroidal anti–inflammatory drugs ibuprofen and indomethacin in pri…

2006

Delivery of proteins into living cells by reversible membrane permeabilization with streptolysin-O

2001

The pore-forming toxin streptolysin O (SLO) can be used to reversibly permeabilize adherent and nonadherent cells, allowing delivery of molecules with up to 100 kDa mass to the cytosol. Using FITC-labeled albumin, 10 5 –10 6 molecules were estimated to be entrapped per cell. Repair of toxin lesions depended on Ca 2+ -calmodulin and on intact microtubules, but was not sensitive to actin disruption or to inhibition of protein synthesis. Resealed cells were viable for days and retained the capacity to endocytose and to proliferate. The active domains of large clostridial toxins were introduced into three different cell lines. The domains were derived from Clostridium difficile B-toxin and Clo…