Search results for "RGD"
showing 10 items of 81 documents
The effects of Borrelia infection on its wintering rodent host
2022
AbstractIn seasonal environments, appropriate adaptations are crucial for organisms to maximize their fitness. For instance, in many species, the immune function has been noticed to decrease during winter, which is assumed to be an adaptation to the season’s limited food availability. Consequences of an infection on the health and survival of the host organism could thus be more severe in winter than in summer. Here, we experimentally investigated the effect of a zoonotic, endemic pathogen, Borrelia afzelii infection on the survival and body condition in its host, the bank vole (Myodes glareolus), during late autumn–early winter under semi-natural field conditions in 11 large outdoor enclos…
Structural characterization of CspZ, a complement regulator factor H and FHL-1 binding protein fromBorrelia burgdorferi
2014
Borrelia burgdorferi is the causative agent of Lyme disease and is found in two different types of hosts in nature - Ixodes ticks and various mammalian organisms. To initiate disease and survive in mammalian host organisms, B. burgdorferi must be able to transfer to a new host, proliferate, attach to different tissue and resist the immune response. To resist the host's immune response, B. burgdorferi produces at least five different outer surface proteins that can bind complement regulator factor H (CFH) and/or factor H-like protein 1 (CFHL-1). The crystal structures of two uniquely folded complement binding proteins, which belong to two distinct gene families and are not found in other bac…
Morphological and biochemical features of Borrelia burgdorferi pleomorphic forms
2015
The spirochaete bacterium Borrelia burgdorferi sensu lato is the causative agent of Lyme disease, the most common tick-borne infection in the northern hemisphere. There is a long-standing debate regarding the role of pleomorphic forms in Lyme disease pathogenesis, while very little is known about the characteristics of these morphological variants. Here, we present a comprehensive analysis of B. burgdorferi pleomorphic formation in different culturing conditions at physiological temperature. Interestingly, human serum induced the bacterium to change its morphology to round bodies (RBs). In addition, biofilm-like colonies in suspension were found to be part of B. burgdorferi’s normal in vitr…
Susceptibility to infection with Borrelia afzelii and TLR2 polymorphism in a wild reservoir host
2019
AbstractThe study of polymorphic immune genes in host populations is critical for understanding genetic variation in susceptibility to pathogens. Controlled infection experiments are necessary to separate variation in the probability of exposure from genetic variation in susceptibility to infection, but such experiments are rare for wild vertebrate reservoir hosts and their zoonotic pathogens. The bank vole (Myodes glareolus) is an important reservoir host of Borrelia afzelii, a tick-borne spirochete that causes Lyme disease. Bank vole populations are polymorphic for Toll-like receptor 2 (TLR2), an innate immune receptor that recognizes bacterial lipoproteins. To test whether the TLR2 polym…
Eliminating Factor H-Binding Activity of Borrelia burgdorferi CspZ Combined with Virus-Like Particle Conjugation Enhances Its Efficacy as a Lyme Dise…
2018
The spirochete Borrelia burgdorferi is the causative agent of Lyme disease, the most common tick-borne disease in the U.S and Europe. No potent human vaccine is currently available. The innate immune complement system is vital to host defense against pathogens, as complement activation on the surface of spirochetes results in bacterial killing. Complement system is inhibited by the complement regulator factor H. To escape killing, B. burgdorferi produces an outer surface protein CspZ that binds factor H to inhibit complement activation on the cell surface. Immunization with CspZ alone does not protect mice from infection, which we speculate is because factor H-binding cloaks potentially pro…
Tick-borne bacteria in Ixodes ricinus collected in southern Norway evaluated by a commercial kit and established real-time PCR protocols
2015
Ticks are important vectors of human pathogens. The knowledge of disease causing agents harboured by ticks in Norway is limited. The focus of this study was (a) to detect the bacteria of medical importance in ticks collected from the vegetation at locations in the southern part of the country and (b) to evaluate a novel commercially available multiplex PCR based method by comparing results with conventional established real-time PCR protocols. Borrelia burgdorferi sensu lato was confirmed to be the most prevalent pathogen detected (31%) among one hundred individually analysed adult ticks. Borrelia miyamotoi, a spirochete associated with relapsing fever, was detected in one sample. Anaplasma…
Hyaluronic Acid Derivative with Improved Versatility for Processing and Biological Functionalization
2016
A hydrophobic/amino functionalized derivative of hyaluronic acid (HA-EDA-C18 ) has been processed by salt leaching technique as porous scaffold without need of chemical crosslinking. Aim of this work is to demonstrate the improved versatility of HA-EDA-C18 in terms of processing and biological functionalization. In particular, the chemical procedure to tether thiol bearing RGD peptide has been described. Moreover, the possibility to load and to control the release of slightly water soluble effectors has been demonstrated by using dexamethasone. First, the swelling and degradation profiles of the scaffolds have been investigated, then the evaluation of metabolic activity of bovine chondrocyt…
Blend scaffolds with polyaspartamide/polyester structure fabricated via TIPS and their RGDC functionalization to promote osteoblast adhesion and prol…
2019
Target of this work was to prepare a RGDC functionalized hybrid biomaterial via TIPS technique to achieve a more efficient control of osteoblast adhesion and diffusion on the three-dimensional (3D) scaffolds. Starting from a crystalline poly(l-lactic acid) (PLLA) and an amorphous alpha,beta-poly(N-2-hydroxyethyl) (2-aminoethylcarbamate)-d,l-aspartamide-graft-polylactic acid (PHEA-EDA-g-PLA) copolymer, blend scaffolds were characterized by an appropriate porosity and pore interconnection. The PHEA-EDA-PLA interpenetration with PLLA improved hydrolytic susceptibility of hybrid scaffolds. The presence of free amino groups on scaffolds allowed to tether the cyclic RGD peptide (RGDC) via Michael…
Attachement and spreading of fibroblasts on an RGD peptide-modified injectable hyaluronan hydrogel
2004
Hyaluronan (HA) hydrogels resist attachment and spreading of fibroblasts and most other mammalian cell types. A thiol-modified HA (3,3'-dithiobis(propanoic dihydrazide) [HA-DTPH]) was modified with peptides containing the Arg-Gly-Asp (RGD) sequence and then crosslinked with polyethylene glycol (PEG) diacrylate (PEGDA) to create a biomaterial that supported cell attachment, spreading, and proliferation. The hydrogels were evaluated in vitro and in vivo in three assay systems. First, the behavior of human and murine fibroblasts on the surface of the hydrogels was evaluated. The concentration and structure of the RGD peptides and the length of the PEG spacer influenced cell attachment and spre…
Prevalence and genotypes of Borrelia burgdorferi sensu lato infection in Ixodes ricinus ticks in southern Norway.
2010
From April to October 2007, host-seeking Ixodes ricinus ticks were collected from 4 locations in southern Norway: Farsund, Mandal, Sogne and Tromoy. Two hundred and ten larvae, 1130 nymphs and 449 adults were investigated for infection with Borrelia burgdorferi sensu lato (s.l.) by real-time polymerase chain reaction (PCR) amplification of the 16S rRNA gene. The total percentage of B. burgdorferi s.l. in nymphal and adult ticks was determined to be 31.3% in Farsund, 25.2% in Mandal, 22.3% in Sogne and 22.1% in Tromoy. Larvae were pooled in groups of 10 before analysis, and Borrelia infection was detected in 1 of the 21 larvae pools. B. burgdorferi s.l. were genotyped by melting curve analys…