15 research outputs found
Chicken Anti-Campylobacter Vaccine – Comparison of Various Carriers and Routes of Immunization
Campylobacter spp, especially the species Campylobacter jejuni, are important human enteropathogens responsible for millions of cases of gastro-intestinal disease worldwide every year. C. jejuni is a zoonotic pathogen, and poultry meat that has been contaminated by microorganisms is recognized as a key source of human infections. Although numerous strategies have been developed and experimentally checked to generate chicken vaccines, the results have so far had limited success. In this study, we explored the potential use of non-live carriers of Campylobacter antigen to combat Campylobacter in poultry. First, we assessed the effectiveness of immunization with orally or subcutaneously delivered GEM (Gram-positive Enhancer Matrix) particles carrying two Campylobacter antigens: CjaA and CjaD. These two immunization routes using GEMs as the vector did not protect against Campylobacter colonization. Thus, we next assessed the efficacy of in ovo immunization using various delivery systems: GEM particles and liposomes. The hybrid protein CjaAD, which is CjaA presenting CjaD epitopes on its surface, was employed as a model antigen. We found that CjaAD administered in ovo at embryonic development day 18 by both delivery systems resulted in significant levels of protection after challenge with a heterologous Campylobacter jejuni strain. In practice, in ovo chicken vaccination is used by the poultry industry to protect birds against several viral diseases. Our work showed that this means of delivery is also efficacious with respect to commensal bacteria such as Campylobacter. In this study, we evaluated the protection after one dose of vaccine given in ovo. We speculate that the level of protection may be increased by a post-hatch booster of orally delivered antigens
Effect of meta-topolin in vitro propagation of Pelargonium x hortorum and Pelargonium x hederaefolium cultivars
July and September. The most efficient regeneration and axillary multiplication were achieved on the medium supplemented with meta-topolin. The application of BAP caused a lower regeneration potency of explants and resulted in a decrease of shoot quality with every subculture. Four of the six cultivars showed growth inhibition after three months of growth on BAP-medium. The highest multiplication rate (2.7-4.7 depending on genotype) and the high quality of shoots were noted on the medium supplemented with mT (0.5-1.0 mg l-1). It is also very important to note that mT had stimulating effect on organogenesis in P. × hederaefolium and P. × hortorum cultivars over the long term. Moreover, meta-topolin had no after-effect on the growth and inhibition of rooting. Only one cultivar ("Sofie Cascade") rooted better on control medium without auxin. In case of the other cultivars, IBA added in concentrations of 0.01-0.1 mg l-1 had a stimulating effect on root production. The higher level of auxin inhibited root formation, stimulated senescence of shoots and had a negative after-effect on acclimatization in greenhouse conditions
Metody rozmnażania liliowca (Hemerocallis spp.) in vitro
Odmiany liliowca można rozmnażać tylko wegetatywnie przez podział roślin i metoda mnożenia jest mało wydajna, szczególnie dla odmian pochodzących najnowszej hodowli. Z tego względu, od wielu lat prowadzone są prace łstosowaniem rozmnażania in vitro w produkcji na skalę masową oraz w bonowych odmian.
W niniejszej pracy zawarto przegląd literatury dotyczący zdolności regenetracyjnych eksplantatów pierwotnych izolowanych z różnych organów liliowca, omówiono rolę egzogennych regulatorów wzrostu oraz czynników środowiska
w regulacji wzrostu liliowca in vitro. Przedstawiono metody rozmnażania in vitro oraz ich zastosowanie w hodowli i produkcji ogrodniczej liliowca. Zwrócono uwagę na problem stabilności genetycznej roślin liliowca pochodzących z rozmnażania in vitro.Daylily cultivars are propagated by rhizome division. However, the conventional propagation is too slow for a large production and breeding, and therefore in vitro methods were developed and used. The regeneration ability of different organs of daylily plants is reported in this review. The role of exogenous plant growth regulators and environmental factors in the growth and development of daylily in vitro is also presented. The paper discusses the application of in vitro propagation methods in a horticultural production and breeding and shows the problem of genetic stability of in vitro propagated daylily plants
Wpływ różnego poziomu cytokininy, sacharozy i soli azotowych na wzrost i rozwój oraz poziom substancji fenolowych w pędach Magnolia x soulangiana 'Coates' in vitro
Phenolics are believed to inhibit the shoot formation in magnolia in vitro. The aim of this study was to determine the influence of sucrose, nitrogen salts and cytokinin concentrations on the phenolics content in relation to shoot formation in Magnolia × soulangiana ‘Coates’ in vitro. The results showed that the concentration and ratios of benzylaminopurine (BAP), sucrose and nitrogen salts in the Murashige and Skoog (MS) medium had a significant effect on the leaf and axillary shoot formation as well as on the phenolics content. The highest multiplication rate (4.8 shoots/explant) and shoots of good quality were obtained on medium containing 0.2 mg·dm-3 BAP, 100% nitrogen salts in relation to the MS medium and 20 g·dm-3 sucrose. At this sucrose level, increasing BAP concentration from 0.2 to 1.0 mg·dm-3 resulted in the inhibition or slight stimulation of shoot formation depending on the nitrogen levels (100 and 75/50%, respectively). At low sucrose-to-nitrogen ratio in the medium, increased BAP levels induced the leaf browning. The highest inhibition of M. × soulangiana ‘Coates’ shoot formation has been observed on medium containing 30 g·dm-3 sucrose, reduced nitrogen salts levels and BAP at concentration 1.0 mg·dm-3. A medium with a high sucrose-to-nitrogen ratio stimulated also phenolics production in magnolia shoots. The addition of BAP lowered phenolics production compared with the control medium. At high sucrose-to-nitrogen ratio, increasing BAP levels significantly stimulated phenolics production. The results of the study showed that not in all the treatments did the enhanced phenolics levels in the shoots of M. × soulangiana ‘Coates’ coincide with decreased shoot formation.Substancje fenolowe wytwarzane podczas wzrostu magnolii in vitro są uważane za czynnik hamujący tworzenie się pędów. Celem badań było określenie wpływu i współdziałania różnego stężenia soli azotowych, sacharozy i cytokininy na wzrost i rozwój pędów Magnolia × soulangiana ‘Coates’ in vitro w zależności od poziomu substancji fenolowych. Badania wykazały, iż tworzenie zarówno pędów i liści, jak i substancji fenolowych, istotnie zależało od stężenia i wzajemnych proporcji cytokininy, sacharozy i soli azotu w pożywce Murashige and Skooga (MS). Najwyższy współczynnik mnożenia się pędów (4,8 pędów/eksplantat) uzyskano na pożywce zawierającej 0,2 mg·dm-3 benzyloaminopuryny (BAP), 100% soli azotowych wg MS i 20 g·dm-3 sacharozy. Przy tym poziomie sacharozy wzrost stężenia BAP (0,2–1,0 mg·dm-3) powodował silną inhibicję lub nieznaczną stymulację tworzenia się pędów w zależności od poziomu azotu, kolejno 100% i 75/50%. Przy niskim stosunku sacharozy do soli azotowych w pożywce, wzrost stężenia BAP indukował brązowienie liści. Czynnikiem istotnie hamującym tworzenie się pędów i liści magnolii in vitro była sacharoza zastosowana w stężeniu 30 g·dm-3, jednak jej działanie zależało od poziomu azotu i cytokininy. Przy wysokiej relacji sacharozy do soli azotowych, tworzenie się pędów było proporcjonalne do stężenia BAP. Wysoka relacja sacharozy do soli azotowych w pożywce wpływała również na podwyższony poziom substancji fenolowych w pędach. W porównaniu z kontrolą (bez cytokininy), pędy rosnące w obecności BAP produkowały mniej substancji fenolowych. Przy wysokim stosunku sacharozy do soli azotowych, wraz ze wzrostem stężenia cytokininy obserwowano jednak istotny wzrost ich poziomu. Na podstawie wyników badań wnioskuje się, że nie we wszystkich traktowaniach podwyższony poziom substancji fenolowych w pędach korelował z inhibicją tworzenia się pędów
Morphological and biochemical responses to gibberellic acid in Magnolia × ‘Spectrum’ in vitro
The total soluble sugar content and antioxidant enzyme activities were studied for the first time during axillary
shoot formation in Magnolia × ‘Spectrum’ in vitro in response to BAP (0.3 mg lˉ¹), different levels of gibberellic
acid (GA3; 0.0, 0.1, 0.5, 1.0 mg lˉ¹), sucrose (20 and 30 g lˉ¹) and nitrogen salts (KNO3/NH4NO3; 100/100% and
75/50% relative to MS medium). Among various GA3 and sucrose/nitrogen salts ratios, the most effective axillary
multiplication (5.9 shoots/explant) and leaf formation (25.7 leaves per multiplied clumps) were obtained after
addition of GA3 at 0.1 mg lˉ¹ to a BAP medium containing 20 g lˉ¹ sucrose and reduced levels of nitrogen salts
(75% KNO3 and 50% NH4NO3). The addition of GA3 to the BAP medium enhanced shoot formation by 36% and
leaf formation by 27%. The highest shoot formation capacity of M. × ‘Spectrum’ in vitro coincided with enhanced
levels of soluble sugar and peroxidase (POD) activity. Increasing GA3 concentration from 0.1 to 1.0 mg lˉ¹ in the
above medium resulted in inhibition of shoot and leaf formation and a decrease in the soluble sugar content.
The influence of GA3 on the activities of catalase (CAT) and POD depended on its concentration and the levels of
sucrose and nitrogen salts in the medium. The highest increase in CAT and POD activities, that coincided with the
enhanced shoot formation capacity of M. × ‘Spectrum’ in vitro, was observed after addition of GA3 to the medium
containing high levels of sucrose and nitrogen salts
The effects of growth regulators, paclobutrazol and light quality on the growth and development of Hostia sieboldiana (HOOK.) ENG. shoots in vitro
Ex vitro rooting, acclimatization and genetic stability of Lonicera caerulea var. kamtschatica
Ex vitro rooting and acclimatization of two cultivars ‘Wojtek’ and ‘Zojka’ of blue honeysuckle (Lonicera caerulea var. kamtschatica Sevast.) were studied. To the ex vitro conditions were transferred rooted and unrooted shoots. The post-effect of auxin type and concentration as well as microcutting and soil substrate types were tested. The genetic stability of the plantlets in relation to the mother plants by using amplified fragment length polymorphism (AFLP) and inter simple sequence repeat (ISSR) markers has been also determined. It has been found that in vitro rooted cuttings of both cultivars showed a higher survival rate (max. 88%) and better growth and development when they were rooted on a medium containing a low auxin level (1.0 mg·dm-3). The results of the second experiment showed successful ex vitro rooting of blue honeysuckle shoots without auxin treatment. Higher ex vitro rooting and survival rate in the greenhouse have been observed for ‘Wojtek’ (max. 96%) than ‘Zojka’ (max. 88%). Better growth and development of shoots and roots were observed on peat alone or a mixture of peat and perlite as compared to a mixture of peat and sand. The micropropagated plantlets appeared similar to mother plants. Molecular analysis confirmed a high level of genetic stability of blue honeysuckle after 2 years of in vitro propagation. However, among the cultivars studied, ‘Wojtek’ showed slightly higher genetic stability than ‘Zojka’ (99.5% and 97.7%, respectively). For ‘Zojka’ plants, the degree of variation was comparable for AFLP and ISSR markers. For ‘Wojtek’, no polymorphism was detected using the ISSR analysis in contrast to the AFLP analysis
Sucrose and cytokinin interactions in relation to ethylene and abscisic acid production in the regulation of morphogenesis in pelargonium x hortorum L.H. Bailey in vitro
The aim of the study was to determine the effect of exogenous sucrose and cytokinin on ethylene production and
responsiveness in relation to the shoot formation of Pelargonium × hortorum 'Bergpalais' in vitro. Increasing
the concentration of sucrose from 15 to 40 g L-1 in medium containing meta-topolin (mT) resulted in a two-fold
decrease in the number of shoots and leaves as well as a reduction in ethylene production. The addition of ethylene
synthesis inhibitor (AVG) to mT-medium significantly reduced the ethylene production and the shoot
growth, but it had no significant influence on the shoot formation. The mT-induced shoot formation was, however,
significantly reduced in the presence of ethylene action inhibitor (AgNO3), in a manner dependent on
sucrose levels. At the end of the subculture period, increased sucrose concentrations (15–40 g L-1) in the presence
of mT and AgNO3 resulted in a 3.7-fold increase in ethylene emission. At the same time, the supply of sucrose
caused a 2.8-fold increase in the level of endogenous abscisic acid (ABA). Our results may suggest that the
inhibitory effect of high sucrose concentration (30 and 40 g L-1) may depend on its influence on ethylene sensitivity.
It also suggests that sucrose-regulation of the shoot formation of Pelargonium in vitro is mediated by ABA
Supplementary Material for: Lactic Acid Bacteria as a Surface Display Platform for Campylobacter jejuni Antigens
<p><b><i>Background:</i></b> Food poisoning and diarrheal diseases continue to pose serious health care and socioeconomic problems worldwide. <i>Campylobacter</i>
spp. is a very widespread cause of gastroenteritis. Over the past
decade there has been increasing interest in the use of lactic acid
bacteria (LAB) as mucosal delivery vehicles. They represent an
attractive opportunity for vaccination in addition to vaccination with
attenuated bacterial pathogens. <b><i>Methods:</i></b> We examined the
binding ability of hybrid proteins to nontreated or trichloroacetic acid
(TCA)-pretreated LAB cells by immunofluorescence and Western blot
analysis. <b><i>Results:</i></b> In this study we evaluated the possibility of using GEM (Gram-positive enhancer matrix) particles of <i>Lactobacillus salivarius</i> as a binding platform for 2 conserved, immunodominant, extracytoplasmic <i>Campylobacter jejuni</i> proteins: CjaA and CjaD. We analyzed the binding ability of recombinant proteins that contain <i>C. jejuni</i> antigens (CjaA or CjaD) fused with the protein anchor (PA) of the <i>L. lactis </i>peptidoglycan
hydrolase AcmA, which comprises 3 LysM motifs and determines
noncovalent binding to the cell wall peptidoglycan. Both fused proteins,
i.e. 6HisxCjaAx3LysM and 6HisxCjaDx3LysM, were able to bind to
nontreated or TCA-pretreated <i>L. salivarius</i> cells. <b><i>Conclusion:</i></b> Our results documented that the LysM-mediated binding system allows us to construct GEM particles that present 2 <i>C. jejuni</i> antigens.</p