Search results for " immune system"

Immunoelectron Microscopy of Hemocyanin from the Keyhole Limpet (Megathura crenulata): A Parallel Subunit Model

1993

Abstract Immunoelectron microscopy has been performed using negatively stained immune complexes of keyhole limpet hemocyanin (KLH) subunit 2 di- and multidecamers with domain-specific monoclonal antibodies. One antibody (KLH2 a macr 1) links the hemocyanin molecules in a side-to-side pattern, whereas the other antibody (KLH2 fg macr 1) links the molecules end-to-end. From existing knowledge of the domain sequence of KLH subunit 2, these data provide support for a parallel arrangement of subunits within each decamer. Ten N-terminal a macr: domains are then present at the noncollar region of each decamer with 10 C-terminal g macr domains at the collar region. The immunonegative staining data …

Additional file 6: of Diversity, evolution, and function of myriapod hemocyanins

2018

Table S3. Expression of hemocyanin subunit mRNA in myriapods. (PDF 72 kb)

A2.34 Specific deletion of β-catenin signalling in dendritic cells results in lower Treg expression without influencing the severity of collagen-indu…

2015

Background and objectives Rheumatoid arthritis (RA) is an autoimmune disease characterised by chronic inflammation and synovial infiltration of immune cells. T-cell priming by activated dendritic cells (DCs) contributes to the pathogenesis of RA. DCs are professional antigen presenting cells that have the dual ability to stimulate immunity and maintain tolerance. However, the signalling pathways mediating the tolerogenic DC function in vivo remain largely unknown. Recently, the b-catenin pathway has been suggested to promote a regulatory DC phenotype in vitro . While activation of β-catenin causes the phenotypic maturation of bone marrow-derived DCs, these cells fail to produce immunogenic …

Quantification of intracranial contribution to rheoencephalography by a numerical model of the head

2000

Abstract Objectives : Partial contributions of intracranial and extracranial circulation to rheoencephalography (REG) remain uncertain. The main goal of this work is to determine theoretically the capability of REG techniques to reflect intracranial blood flow. Methods : Head and current injection electrodes were computationally modeled to assess REG sensitivity to brain and scalp conductivity changes. Data obtained were related to tissue perfusions to calculate the partial contribution of cerebral blood perfusion to REG I, REG II and monopolar REG and to assess their amplitudes. Results : When REG I and monopolar REG were used, the theoretical maximum of intracranial contribution was reach…

Molecular/chemical ecology in sponges. Evidence for an adaptive antibacterial response in Suberites domuncola

2004

Sponges (Porifera) represent the evolutionary oldest metazoan phylum still extant today. They have developed a complex Bauplan, based on the existence of structural and regulatory molecules; many of these have been cloned and analyzed in the past years. The demosponge Suberites domuncula has been used as a suitable model to demonstrate that these animals not only possess an adaptive immune response on the level of cytokines, but also, as pointed out here, on the level of synthesis of bioactive alkyl-lipid derivatives. From specimens of S. domuncula the two lyso-PAF (platelet-activating factor) compounds, 1-O-hexadecyl-sn-glycero-3-phosphocholine and 1-O-octadecyl-sn-glycero-3-phosphocholine…

Molecular Design of the Cαβ Interface Favors Specific Pairing of Introduced TCRαβ in Human T Cells

2008

Abstract A promising approach to adoptive transfer therapy of tumors is to reprogram autologous T lymphocytes by TCR gene transfer of defined Ag specificity. An obstacle, however, is the undesired pairing of introduced TCRα- and TCRβ-chains with the endogenous TCR chains. These events vary depending on the individual endogenous TCR and they not only may reduce the levels of cell surface-introduced TCR but also may generate hybrid TCR with unknown Ag specificities. We show that such hybrid heterodimers can be generated even by the pairing of human and mouse TCRα- and TCRβ-chains. To overcome this hurdle, we have identified a pair of amino acid residues in the crystal structure of a TCR that …

The Role of Lectins in Finfish: A Review

2019

The immune system of vertebrates involves both innate and acquired immune responses. The innate immunity is more generalized with robust response whereas the other has a highly specific response to infectious pathogens. Because of the lack of specialized lymphatic organs, innate immunity is an important mode of defense in fishes. The less specific innate immune system acts mainly through complement pathway which depends on pattern-based recognition of “self” and “non-self” targets by host lectins and associated proteins. This ultimately results in the clearance of target cells. Lectins are glycoproteins which possess at least one carbohydrate recognition domain (CRD) that specifically and r…

2015

AbstractTriggering receptor expressed on myeloid cells (TREM)-1 plays an important role in innate immune responses and is upregulated under infectious as well as non-infectious conditions. In addition, a soluble TREM-1 variant (sTREM-1) is detectable in sera or bronchoalveolar-lavage fluids from patients. Currently, various studies are difficult to compare, since the methods of detection by enzyme-linked immunosorbent assays (ELISA) vary among different research groups. In this study, we compared three different s-TREM-1 specific ELISAs and identified individual assay characteristics finding notable differences in sTREM-1 concentrations in part depending on the employed buffers. Investigati…

Molecular characterization of the phenolic acid metabolism in the lactic acid bacteria Lactobacillus plantarum

2001

The lactic acid bacteria Lactobacillus plantarumdisplays substrate-inducible decar- boxylase activities on p-coumaric, caffeic and ferulic acids. Purification of the p-coumaric acid decarboxylase (PDC) was performed. Sequence of the N-terminal part of the PDC led to the cloning of the corresponding pdc gene. Expression of this gene in Escherichia colirevealed that PDC displayed a weak activity on ferulic acid, detectable in vitro in the presence of ammonium sulfate. Transcrip- tional studies of this gene in L. plantarum demonstrated that the pdc transcription is phenolic acid- dependent. A mutant deficient in the PDC activity, designated LPD1, was constructed to study phe- nolic acid altern…

Non-Vertebrate Nitric Oxide Synthases

2007

NO is an important signalling molecule making essential contributions to innate immunity in mammals. Interestingly, also several non-vertebral NOS have been described. Aside from a role in the feeding of bloodsucking insects, NO has been shown, for example, to play an important role in Drosophila innate immunity …