Isolation and1H-NMR spectroscopic identification of the glucose-containing lipid-linked precursor oligosaccharide ofN-linked carbohydrate chains

The lipid-linked precursor ofN-type glycoprotein oligosaccharides was isolated from porcine thyroid microsomes after in cubation with UDP[³H] Glucose. The carbohydrate was released from dolichol pyrophosphate by mild acid hydrolysis, purified by gel filtration and characterized by 500-MHz¹H-NMR spectroscopy in combination with enzymatic degradation. The parent oligosaccharide was found to be Glc₃Man₉Glc-NAc₂. The three glucose residues are present in the linear sequence Glcα1-2Glα1-3 Glc, the latter being α(1-3)-linked to one of the mannose residues. In order to establish the branch location of the triglucosyl unit, the parent compound was digested with jack-bean α-mannosidase. The oligosaccharide product was purified by gel filtration, and identified by¹H-NMR as Glc₃Man₅GlcNAc₂ lacking the mannose residues A, D₂, B and D₃. Therefore, the structure of the precursor oligosaccharide is as follows: $$\begin{gathered} c b a D_1 C 4 \hfill \\ Glc\alpha 1 - 2Glc\alpha 1 - 3Glc\alpha 1 - 3Man\alpha 1 - 2Man\alpha 1 - 2Man\alpha 1 \hfill \\ 3 \swarrow 3 2 1 \hfill \\ Man\alpha 1 - 2Man\alpha 1 Man\beta 1 - 4GlcNAc\beta 1 - 4GlcNAc \hfill \\ D_{2 } A 3 6 \hfill \\ Man\alpha 1 \hfill \\ 6 \hfill \\ Man\alpha 1 - 2Man\alpha 1 \nwarrow 4 \hfill \\ D_3 B \hfill \\ \end{gathered} $$      

Cell-mediated DNA transport between distant inflammatory sites following intradermal DNA immunization in the presence of adjuvant

After intradermal genetic immunization, naked DNA is transported from the site of injection to regional lymph nodes. Little is known on how inflammation influences this process and whether DNA is transported beyond local lymph nodes. In the experiments herein reported, we injected naked DNA in the presence of adjuvant to address questions related to 1) the fate of naked DNA in the presence of inflammation; 2) the generation of immune responses to the encoded protein during inflammation; and, more in general, 3) the fate of ingested molecules beyond regional lymph nodes during inflammation. Two sites of inflammation were induced in vivo in mice. Naked DNA was injected in the nape together with adjuvant, and adjuvant only was injected at a distant peritoneal site. Injected DNA, uptaken at the primary dermal site of inflammation, was transported beyond regional lymph nodes to distant organs such as the spleen and to the distant peritoneal site of inflammation. This transport, mediated by CD11b+ cells, was cumulative during chronic inflammation. These results indicate a novel route of transport of DNA beyond regional lymph nodes and may have specific implications for DNA-based immune modulation.     

Increased expression of costimulatory markers CD134 and CD80 on interleukin-17 producing T cells in patients with systemic lupus erythematosus

Introduction  

There is growing evidence that interleukin 17 (IL-17) producing T cells are involved in the pathogenesis of systemic lupus erythematosus (SLE). Previous studies showed that increased percentages of T-cell subsets expressing the costimulatory molecules CD80 and CD134 are associated with disease activity and renal involvement in SLE. The aim of this study was to investigate the distribution and phenotypical characteristics of IL-17 producing T-cells in SLE, in particular in patients with lupus nephritis, with emphasis on the expression of CD80 and CD134.     

Baseline predictors of response and discontinuation of tumor necrosis factor-alpha blocking therapy in ankylosing spondylitis: a prospective longitudinal observational cohort study

Introduction  

Identifying ankylosing spondylitis (AS) patients who are likely to benefit from tumor necrosis factor-alpha (TNF-α) blocking therapy is important, especially in view of the costs and potential side effects of these agents. Recently, the AS Disease Activity Score (ASDAS) has been developed to assess both subjective and objective aspects of AS disease activity. However, data about the predictive value of the ASDAS with respect to clinical response to TNF-α blocking therapy are lacking. The aim of the present study was to identify baseline predictors of response and discontinuation of TNF-α blocking therapy in AS patients in daily clinical practice.     

Advanced glycation endproducts are increased in rheumatoid arthritis patients with controlled disease

Introduction  

Advanced glycation end products (AGEs) are produced and can accumulate during chronic inflammation, as might be present in patients with rheumatoid arthritis (RA). AGEs are involved in the development of cardiovascular disease. The aim of this study is to evaluate whether AGEs are increased in patients with long-standing RA and whether AGE accumulation is related to disease activity, disease severity and measures of (premature) atherosclerosis, such as endothelial activation, endothelial dysfunction and intima media thickness (IMT).     

Expression of collier in the premandibular segment of myriapods: support for the traditional Atelocerata concept or a case of convergence?

Background  

A recent study on expression and function of the ortholog of the Drosophila collier (col) gene in various arthropods including insects, crustaceans and chelicerates suggested a de novo function of col in the development of the appendage-less intercalary segment of insects. However, this assumption was made on the background of the now widely-accepted Pancrustacea hypothesis that hexapods represent an in-group of the crustaceans. It was therefore assumed that the expression of col in myriapods would reflect the ancestral state like in crustaceans and chelicerates, i.e. absence from the premandibular/intercalary segment and hence no function in its formation.     

A mutation linked with autism reveals a common mechanism of endoplasmic reticulum retention for the alpha,beta-hydrolase fold protein family

A mutation linked to autistic spectrum disorders encodes an Arg to Cys replacement in the C-terminal portion of the extracellular domain of neuroligin-3. The solvent-exposed Cys causes virtually complete retention of the protein in the endoplasmic reticulum when the protein is expressed in transfected cells. An identical Cys substitution was reported for butyrylcholinesterase through genotyping patients with post-succinylcholine apnea. Neuroligin, butyrylcholinesterase, and acetylcholinesterase are members of the alpha,beta-hydrolase fold family of proteins sharing sequence similarity and common tertiary structures. Although these proteins have distinct oligomeric assemblies and cellular dispositions, homologous Arg residues in neuroligin-3 (Arg-451), in butyrylcholinesterase (Arg-386), and in acetylcholinesterase (Arg-395) are conserved in all studied mammalian species. To examine whether an homologous Arg to Cys mutation affects related proteins similarly despite their differing capacities to oligomerize, we inserted homologous mutations in the acetylcholinesterase and butyrylcholinesterase cDNAs. Using confocal fluorescence microscopy and analysis of oligosaccharide processing, we find that the homologous Arg to Cys mutation also results in endoplasmic reticulum retention of the two cholinesterases. Small quantities of mutated acetylcholinesterase exported from the cell retain activity but show a greater K(m), a much smaller k(cat), and altered substrate inhibition. The nascent proteins associate with chaperones during processing, but the mutation presumably restricts processing through the endoplasmic reticulum and Golgi apparatus, because of local protein misfolding and inability to oligomerize. The mutation may alter the capacity of these proteins to dissociate from their chaperone prior to oligomerization and processing for export.     

Systems analysis of primary Sjögren's syndrome pathogenesis in salivary glands identifies shared pathways in human and a mouse model

Bone tissue has an exceptional quality to regenerate to native tissue in response to injury. However, the fracture repair process requires mechanical stability or a viable biological microenvironment or both to ensure successful healing to native tissue. An improved understanding of the molecular and cellular events that occur during bone repair and remodeling has led to the development of biologic agents that can augment the biological microenvironment and enhance bone repair. Orthobiologics, including stem cells, osteoinductive growth factors, osteoconductive matrices, and anabolic agents, are available clinically for accelerating fracture repair and treatment of compromised bone repair situations like delayed unions and nonunions. Preclinical and clinical studies using biologic agents like recombinant bone morphogenetic proteins have demonstrated an efficacy similar or better than that of autologous bone graft in acute fracture healing. A lack of standardized outcome measures for comparison of biologic agents in clinical fracture repair trials, frequent off-label use, and a limited understanding of the biological activity of these agents at the bone repair site have limited their efficacy in clinical applications.