The current incidence of Escherichia coli strains in healthy humans capable of producing the inhibitory exoproducts, such as temperate bacteriophages, corpuscular or HMW (high-molar mass) and proteinaceous or LMW (low-molar mass) colicins and siderophores was determined. Fifty-three E. coli strains were collected from the colons of 53 healthy human volunteers in Brno (Czechia) and tested for spontaneous and induced production of inhibitory exoproducts in a cross-test against each other. Of the strains tested, 37.7% produced bacteriophages, 41.5% produced from one to several LMW colicins, 11.3% formed HMW colicins and 15.1% (eight strains) produced exocellular siderophores different from enterochelin. Of these, seven strains formed aerobactin and one strain formed an untyped siderophore. E. coli strains differ greatly in the incidence of colicinogeny and lysogeny from its closest systemic relatives in the genus Escherichia and therefore should not be regarded as a model bacterium in this respect.

• MeSH
• antibióza fyziologie   MeSH
• bakteriofágy metabolismus   MeSH
• Escherichia coli metabolismus   MeSH
• feces mikrobiologie   MeSH
• koliciny metabolismus   farmakologie   MeSH
• kolon mikrobiologie   MeSH
• lidé MeSH
• lyzogenie fyziologie   MeSH
• siderofory metabolismus   farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• koliciny MeSH
• siderofory MeSH

The human UDP-N-acetyl-α-d-galactosamine:polypeptide N-acetylgalactosaminyl-transferase 2 (GalNAc-T2) is one of the key enzymes that initiate synthesis of hinge-region O-linked glycans of human immunoglobulin A1 (IgA1). We designed secreted soluble form of human GalNAc-T2 as a fusion protein containing mouse immunoglobulin light chain kappa secretory signal and expressed it using baculovirus and mammalian expression vectors. The recombinant protein was secreted by insect cells Sf9 and human HEK 293T cells in the culture medium. The protein was purified from the media using affinity Ni-NTA chromatography followed by stabilization of purified protein in 50mM Tris-HCl buffer at pH 7.4. Although the purity of recombinant GalNAc-T2 was comparable in both expression systems, the yield was higher in Sf9 insect expression system (2.5mg of GalNAc-T2 protein per 1L culture medium). The purified soluble recombinant GalNAc-T2 had an estimated molecular mass of 65.8kDa and its amino-acid sequence was confirmed by mass-spectrometric analysis. The enzymatic activity of Sf9-produced recombinant GalNAc-T2 was determined by the quantification of enzyme-mediated attachment of GalNAc to synthetic IgA1 hinge-region peptide as the acceptor and UDP-GalNAc as the donor. In conclusion, murine immunoglobulin kappa secretory signal was used for production of secreted enzymatically active GalNAc-T2 in insect baculovirus expression system.

• MeSH
• aktivace enzymů MeSH
• Baculoviridae genetika   metabolismus   MeSH
• genetické vektory genetika   metabolismus   MeSH
• HEK293 buňky MeSH
• hmyz genetika   metabolismus   MeSH
• imunoglobulin A genetika   metabolismus   MeSH
• imunoglobuliny - kappa-řetězce chemie   genetika   MeSH
• klonování DNA MeSH
• kultivační média metabolismus   MeSH
• lidé MeSH
• molekulární sekvence - údaje MeSH
• myši MeSH
• N-acetylgalaktosaminyltransferasy biosyntéza   genetika   izolace a purifikace   MeSH
• plazmidy genetika   metabolismus   MeSH
• polypeptid-N-acetylgalaktosaminyltransferasa MeSH
• proteiny - lokalizační signály MeSH
• rekombinantní fúzní proteiny biosyntéza   genetika   izolace a purifikace   MeSH
• rozpustnost MeSH
• sekvence aminokyselin MeSH
• stabilita proteinů MeSH
• tandemová hmotnostní spektrometrie MeSH
• transfekce MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• srovnávací studie MeSH
• Názvy látek
• imunoglobulin A MeSH
• imunoglobuliny - kappa-řetězce MeSH
• kultivační média MeSH
• N-acetylgalaktosaminyltransferasy MeSH
• proteiny - lokalizační signály MeSH
• rekombinantní fúzní proteiny MeSH

UNLABELLED: In this work alpha tricalcium phosphate (α-TCP)/iron (Fe) composites were developed as a new family of biodegradable, load-bearing and cytocompatible materials. The composites with composition from pure ceramic to pure metallic samples were consolidated by pulsed electric current assisted sintering to minimise processing time and temperature while improving their mechanical performance. The mechanical strength of the composites was increased and controlled with the Fe content, passing from brittle to ductile failure. In particular, the addition of 25 vol% of Fe produced a ceramic matrix composite with elastic modulus much closer to cortical bone than that of titanium or biodegradable magnesium alloys and specific compressive strength above that of stainless steel, chromium-cobalt alloys and pure titanium, currently used in clinic for internal fracture fixation. All the composites studied exhibited higher degradation rate than their individual components, presenting values around 200 μm/year, but also their compressive strength did not show a significant reduction in the period required for bone fracture consolidation. Composites showed preferential degradation of α-TCP areas rather than β-TCP areas, suggesting that α-TCP can produce composites with higher degradation rate. The composites were cytocompatible both in indirect and direct contact with bone cells. Osteoblast-like cells attached and spread on the surface of the composites, presenting proliferation rate similar to cells on tissue culture-grade polystyrene and they showed alkaline phosphatase activity. Therefore, this new family of composites is a potential alternative to produce implants for temporal reduction of bone fractures. STATEMENT OF SIGNIFICANCE: Biodegradable alpha-tricalcium phosphate/iron (α-TCP/Fe) composites are promising candidates for the fabrication of temporal osteosynthesis devices. Similar to biodegradable metals, these composites can avoid implant removal after bone fracture healing, particularly in young patients. In this work, α-TCP/Fe composites are studied for the first time in a wide range of compositions, showing not only higher degradation rate in vitro than pure components, but also good cytocompatibility and mechanical properties controllable with the Fe content. Ceramic matrix composites show high specific strength and low elastic modulus, thus better fulfilling the requirements for bone fractures fixation. A significant advance over previous works on the topic is the use of pulsed electric current assisted sintering together with α-TCP, convenient to improve the mechanical performance and degradation rate, respectively.

• Klíčová slova
• Biodegradable metal, Degradation test, Mechanical properties, Spark plasma sintering, Tricalcium phosphate,
• MeSH
• fosforečnany vápenaté farmakologie   MeSH
• fraktury kostí farmakoterapie   metabolismus   patologie   MeSH
• keramika farmakologie   MeSH
• kostní náhrady farmakologie   MeSH
• lidé MeSH
• modul pružnosti MeSH
• nádorové buněčné linie MeSH
• osteoblasty metabolismus   patologie   MeSH
• testování materiálů MeSH
• železo farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alpha-tricalcium phosphate MeSH Prohlížeč
• beta-tricalcium phosphate MeSH Prohlížeč
• fosforečnany vápenaté MeSH
• kostní náhrady MeSH
• železo MeSH

Vaccination is historically one of the most successful strategies for the prevention of infectious diseases. For safety reasons, modern vaccinology tends toward the usage of inactivated or attenuated microorganisms and uses predominantly subunit vaccines. The antigens need to be clearly defined, pure, stable, appropriately composed, and properly presented to the immune system of the host. Differing ratios of various proportions between specific CD4+ and CD8+ T cell responses are essential for conferring the required protection in the case of individual vaccines. To stimulate both CD4+ and CD8+ T cells, the antigens must be processed and presented to both antigen-presentation pathways, MHC I and MHC II. Protein antigens delivered by vaccination are processed as extracellular antigens. However, extracellularly delivered antigen can be directed towards intracellular presentation pathways in conjugation with molecules involved in antigen cross-presentation, e.g. heat shock proteins, or by genomic-DNA vaccination. In this overview, current knowledge of the host immune response to DNA vaccines is summarized in the introduction. The subsequent sections discuss techniques for enhancing DNA vaccine efficacy, such as DNA delivery to specific tissues, delivery of DNA to the cell cytoplasm or nucleus, and enhancement of the immune response using molecular adjuvants. Finally, the prospects of DNA vaccination and ongoing clinical trials with various DNA vaccines are discussed.

• MeSH
• aktivace lymfocytů MeSH
• DNA vakcíny * aplikace a dávkování   škodlivé účinky   imunologie   MeSH
• genetické vektory * MeSH
• klinické zkoušky jako téma MeSH
• lékové transportní systémy MeSH
• lidé MeSH
• předpověď MeSH
• prezentace antigenu MeSH
• tvorba protilátek MeSH
• vakcinace * trendy   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• DNA vakcíny * MeSH

The present work studies the microstructure and mechanical performance of tricalcium phosphate (TCP) based cermet toughened by iron particles. A novelty arises by the employment of spark plasma sintering for fabrication of the cermet. Results showed partial transformation of initial alpha TCP matrix to beta phase and the absence of oxidation of iron particles, as well as a lack of chemical reaction between TCP and iron components during sintering. The values of compressive and tensile strength of TCP/Fe cermet were 3.2 and 2.5 times, respectively, greater than those of monolithic TCP. Fracture analysis revealed the simultaneous action of crack-bridging and crack-deflection microstructural toughening mechanisms under compression. In contrast, under tension the reinforcing mechanism was only crack-bridging, being the reason for smaller increment of strength. Elastic properties of the cermet better matched values reported for human cortical bone. Thereby the new TCP/Fe cermet has potential for eventual use as a material for bone fractures fixation under load-bearing conditions.

• Klíčová slova
• Ceramic-matrix composite, Fractography, Microstructural toughening, Spark plasma sintering, Tricalcium phosphate,
• MeSH
• cementy Cermet chemie   MeSH
• fosforečnany vápenaté chemie   MeSH
• mechanické jevy * MeSH
• plazmové plyny chemie   MeSH
• testování materiálů MeSH
• tvrdost MeSH
• železo chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• cementy Cermet MeSH
• fosforečnany vápenaté MeSH
• plazmové plyny MeSH
• tricalcium phosphate MeSH Prohlížeč
• železo MeSH

Glycosylation abnormalities have been observed in autoimmune diseases and cancer. Here, we compare mechanisms of aberrant O-glycosylation, i.e., formation of Tn and sialyl-Tn structures, on MUC1 in breast cancer, and on IgA1 in an autoimmune disease, IgA nephropathy. The pathways of aberrant O-glycosylation, although different for MUC1 and IgA1, include dysregulation in glycosyltransferase expression, stability, and/or intracellular localization. Moreover, these aberrant glycoproteins are recognized by antibodies, although with different consequences. In breast cancer, elevated levels of antibodies recognizing aberrant MUC1 are associated with better outcome, whereas in IgA nephropathy, the antibodies recognizing aberrant IgA1 are part of the pathogenetic process.

• MeSH
• adenokarcinom imunologie   MeSH
• glykosylace MeSH
• IgA nefropatie imunologie   MeSH
• imunoglobulin A chemie   imunologie   MeSH
• lidé MeSH
• molekulární sekvence - údaje MeSH
• mucin 1 chemie   imunologie   MeSH
• nádory prsu imunologie   MeSH
• polysacharidy chemie   imunologie   MeSH
• protilátky chemie   imunologie   MeSH
• prsy imunologie   MeSH
• sacharidové sekvence MeSH
• sekvence aminokyselin MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• imunoglobulin A MeSH
• mucin 1 MeSH
• polysacharidy MeSH
• protilátky MeSH

Lyme disease caused by spirochete Borrelia burgdorferi sensu lato, is a tick-born illness. If the infection is not eliminated by the host immune system and/or antibiotics, it may further disseminate and cause severe chronic complications. The immune response to Borrelia is mediated by phagocytic cells and by Borrelia-specific complement-activating antibodies associated with Th1 cell activation. A new experimental vaccine was constructed using non-lipidized form of recombinant B. burgdorferi s.s. OspC protein was anchored by metallochelating bond onto the surface of nanoliposomes containing novel nonpyrogenic lipophilized norAbuMDP analogues denoted MT05 and MT06. After i.d. immunization, the experimental vaccines surpassed Alum with respect to OspC-specific titers of IgG2a, IgG2b isotypes when MT06 was used and IgG3, IgM isotypes when MT05 was used. Both adjuvants exerted a high adjuvant effect comparable or better than MDP and proved themselves as nonpyrogenic.

• MeSH
• acetylmuramyl-alanyl-isoglutamin chemie   toxicita   MeSH
• antigeny bakteriální imunologie   MeSH
• Borrelia burgdorferi imunologie   MeSH
• chelátory chemie   toxicita   MeSH
• diferenciální skenovací kalorimetrie MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• ELISA MeSH
• liposomy MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• nanočástice chemie   toxicita   MeSH
• nosiče léků chemie   toxicita   MeSH
• proteiny vnější bakteriální membrány imunologie   MeSH
• protilátky bakteriální krev   MeSH
• radiační rozptyl MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• světlo MeSH
• transmisní elektronová mikroskopie MeSH
• vakcína proti lymeské nemoci aplikace a dávkování   imunologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• acetylmuramyl-alanyl-isoglutamin MeSH
• antigeny bakteriální MeSH
• chelátory MeSH
• liposomy MeSH
• nosiče léků MeSH
• OspC protein MeSH Prohlížeč
• proteiny vnější bakteriální membrány MeSH
• protilátky bakteriální MeSH
• vakcína proti lymeské nemoci MeSH

IgA nephropathy (IgAN) is the most common type of glomerulonephritis. Its etiology involves an increased production of polymeric immunoglobulin A1 with an abnormal composition of some carbohydrate chains. The reaction of these abnormal forms of IgA1 with specific autoantibodies while circulating immune complexes arise and settle in the renal mesangium with subsequent inflammatory activation of mesangial cells which in up to 50% of cases results in end-stage kidney failure. Pathogenesis involves an interplay of genetic predisposition and environmental effects, mainly of microbial nature. Current therapy is not sufficiently effective and lacks the focus on the cause of the disease, therefore more efficient and specific ways of therapy are being sought to target the individual stages of the pathogenetic process of IgAN development. With the accumulation of knowledge, new questions arise, concerning detailed mechanisms of the pathological processes, as discussed in the text.Key words: autoimmunity - glycosylation of IgA hinge region - IgA nephropathy - immunoglobulin IgA - IgA1 hinge region.

• MeSH
• chronické selhání ledvin * MeSH
• glomerulární mesangium patofyziologie   MeSH
• glykosylace MeSH
• IgA nefropatie * etiologie   terapie   MeSH
• imunoglobulin A MeSH
• ledviny MeSH
• lidé MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• imunoglobulin A MeSH

IgA nephropathy is currently the most frequently investigated glomerulonephritis. The disease is defined by the presence of dominant or co-dominant deposits of IgA1 in the glomerular mesangium. Circulating immune complexes are most likely the source of the deposited IgA1. However, it is also possible that the aggregates of structurally altered IgA1 or enhanced binding to IgA receptors expressed on mesangial cells lead to deposition. The cause of the formation of immune complexes responsible for IgA nephropathy lies in the incomplete O-linked oligosaccharide side chains, which, due to the deficiency of corresponding glycosyltransferases, lack terminal galactose residues leading to the exposure of N-acetylgalactosamine. Naturally occurring antibodies of the IgG or IgA1 isotype bind to this sugar antigen. In the clinical course, we differentiate between the early stage usually characterized by hematuria, and a variable late stage characterized either by a clinical remission, by persistence of hematuria, or by increasing proteinuria and blood pressure and decreasing renal function in one third of the patients. In the early stage, it is difficult to predict the prognosis of IgA nephropathy, either on the basis of clinical presentation and morphological findings, or according to the level of galactose-deficient IgA1 in the circulation. The reliable criteria of serious prognosis emerge only in the later stages of the disease and include proteinuria, hypertension, and histologically apparent tubular atrophy and interstitial sclerosis. The dominant trend in the treatment of IgA nephropathy is the emphasis on administration of ACE inhibitors/sartans, which are introduced into the treatment at the time of microalbuminuria. If proteinuria does not decrease below 1 g/24 h, treatment with prednisone is justifiable. New findings concerning the molecular/cellular mechanism involved in the pathogenesis of IgA nephropathy suggest the possible therapeutical interference with the generation of nephritogenic immune complexes by a selective blocking of the IgA1 molecules with altered glycan structures using monovalent reagents.

• Klíčová slova
• IgA nephropathy - immunoglobulin A - O-glycosylation - immune complexes - therapy.,
• MeSH
• IgA nefropatie terapie   MeSH
• lidé MeSH
• management nemoci * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

PURPOSE: The aim of this work was to demonstrate an immunostimulatory and adjuvant effect of new apyrogenic lipophilic derivatives of norAbuMDP and norAbuGMDP formulated in nanoliposomes. METHODS: Nanoliposomes and metallochelating nanoliposomes were prepared by lipid film hydration and extrusion methods. The structure of the liposomal formulation was studied by electron microscopy, AF microscopy, and dynamic light scattering. Sublethal and lethal γ-irradiation mice models were used to demonstrate stimulation of innate immune system. Recombinant Hsp90 antigen (Candida albicans) bound onto metallochelating nanoliposomes was used for immunisation of mice to demonstrate adjuvant activities of tested compounds. RESULTS: Safety and stimulation of innate and adaptive immunity were demonstrated on rabbits and mice. The liposomal formulation of norAbuMDP/GMDP was apyrogenic in rabbit test and lacking any side effect in vivo. Recovery of bone marrow after sublethal γ-irradiation as well as increased survival of mice after lethal irradiation was demonstrated. Enhancement of specific immune response was demonstrated for some derivatives incorporated in metallochelating nanoliposomes with recombinant Hsp90 protein antigen. CONCLUSIONS: Liposomal formulations of new lipophilic derivatives of norAbuMDP/GMDP proved themselves as promising adjuvants for recombinant vaccines as well as immunomodulators for stimulation of innate immunity and bone-marrow recovery after chemo/radio therapy of cancer.

• MeSH
• acetylmuramyl-alanyl-isoglutamin aplikace a dávkování   analogy a deriváty   chemie   farmakologie   terapeutické užití   MeSH
• adaptivní imunita účinky léků   MeSH
• adjuvancia imunologická aplikace a dávkování   chemie   farmakologie   terapeutické užití   MeSH
• analýza přežití MeSH
• antigeny fungální imunologie   MeSH
• experimentální radiační poranění imunologie   prevence a kontrola   MeSH
• králíci MeSH
• liposomy MeSH
• mikroskopie atomárních sil MeSH
• mikroskopie elektronová rastrovací MeSH
• molekulární struktura MeSH
• myši inbrední ICR MeSH
• myši MeSH
• nanočástice MeSH
• nosiče léků chemie   MeSH
• přirozená imunita účinky léků   MeSH
• proteiny tepelného šoku HSP90 imunologie   MeSH
• protilátky fungální krev   MeSH
• rekombinantní proteiny imunologie   MeSH
• transmisní elektronová mikroskopie MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• acetylmuramyl-alanyl-isoglutamin MeSH
• adjuvancia imunologická MeSH
• antigeny fungální MeSH
• glucosaminylmuramyl-2-alanine-D-isoglutamine MeSH Prohlížeč
• liposomy MeSH
• N-acetylmuramyl-aminobutyryl-isoglutamine MeSH Prohlížeč
• nosiče léků MeSH
• proteiny tepelného šoku HSP90 MeSH
• protilátky fungální MeSH
• rekombinantní proteiny MeSH