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The Ocular Conjunctiva as a Mucosal Immunization Route: A Profile of the Immune Response to the Model Antigen Tetanus Toxoid
Get PDFBackground: In a quest for a needle-free vaccine administration strategy, we evaluated the ocular conjunctiva as an alternative mucosal immunization route by profiling and comparing the local and systemic immune responses to the subcutaneous or conjunctival administration of tetanus toxoid (TTd), a model antigen. Materials and methods: BALB/c and C57BL/6 mice were immunized either subcutaneously with TTd alone or via the conjunctiva with TTd alone, TTd mixed with 2% glycerol or TTd with merthiolate-inactivated whole-cell B. pertussis (wBP) as adjuvants. Mice were immunized on days 0, 7 and 14 via both routes, and an evaluation of the local and systemic immune responses was performed two weeks after the last immunization. Four weeks after the last immunization, the mice were challenged with a lethal dose (2 x LD50) of tetanus toxin. Results: The conjunctival application of TTd in BALB/c mice induced TTd-specific secretory IgA production and skewed the TTd-specific immune response toward a Th1/Th17 profile, as determined by the stimulation of IFN gamma and IL-17A secretion and/or the concurrent pronounced reduction of IL-4 secretion, irrespective of the adjuvant. In conjunctivaly immunized C57BL/6 mice, only TTd administered with wBP promoted the establishment of a mixed Th1/Th17 TTd-specific immune response, whereas TTd alone or TTd in conjunction with glycerol initiated a dominant Th1 response against TTd. Immunization via the conjunctiva with TTd plus wBP adjuvant resulted in a 33% survival rate of challenged mice compared to a 0% survival rate in non-immunized animals (p lt 0.05). Conclusion: Conjunctival immunization with TTd alone or with various adjuvants induced TTd-specific local and systemic immune responses, predominantly of the Th1 type. The strongest immune responses developed in mice that received TTd together with wBP, which implies that this alternative route might tailor the immune response to fight intracellular bacteria or viruses more effectively
Adjuvant dependence of APS pathology-related low-affinity antibodies during secondary immune response to tetanus toxoid in BALB/c mice
No full textOne of the established animal models for autoimmune disease antiphospholipid syndrome (APS) is TTd hyperimmunization of mice. Tetanus toxoid (TTd) and plasma protein beta(2)GPI share structural homology so that immunization with TTd induces appearance of cross-reactive antibodies. In this paper, we have investigated the presence and dynamic of fluctuation of specific (anti-TTd) and auto (anti-beta(2)GPI) antibodies induced in BALB/c mice during secondary immune response after TTd immunization with alhydrogel or glycerol as adjuvants. In addition, we followed the induced reproductive pathology as a sign of autoimmune outcome. We show undoubtedly adjuvant dependance of (1) level of induced anti-TTd IgG antibodies, (2) changes in levels of low-affinity anti-beta(2)GPI IgG antibodies, and (3) change in fecundity and fertility during secondary immune response. These findings once more indicate the importance of chosen adjuvants used for successful immunization and eventual autoantibody outcome, this time associated with the processes involving low affinity, natural antibodies
Passive immunization with a recombinant adenovirus expressing an HA (H5)-specific single-domain antibody protects mice from lethal influenza infection
No full textOne effective method for the prevention and treatment of influenza infection is passive immunization. In our study, we examined the feasibility of creating an antibody-based preparation with a prolonged protective effect against influenza virus. Single-domain antibodies (sdAbs) specific for influenza virus hemagglutinin were generated. Experiments in mouse models showed 100% survivability for both intranasal sdAbs administration 24h prior to influenza challenge and 24h after infection. sdAb-gene delivery by an adenoviral vector led to gene expression for up to 14days. Protection by a recombinant adenovirus containing the sdAb gene was observed in cases of administration prior to influenza infection (14d–24h). We also demonstrated that the single administration of a combined preparation containing sdAb DNA and protein expanded the protection time window from 14d prior to 48h after influenza infection. This approach and the application of a broad-spectrum sdAbs will allow the development of efficient drugs for the prevention and treatment of viral infections produced by pandemic virus variants and other infections
Ovarian hormone withdrawal in prepubertal developmental stage does not prevent thymic involution in rats
No full textThe study was undertaken to assess the effects of ovarian hormone withdrawal in prepubertal age on thymopoiesis in 2- (young) and 11-month-old (middle-aged) rats. In ovariectomized (Ox) rats, irrespective of age, thymic weight and cellularity were greater than in age-matched controls, but the values of both parameters exhibited the age-related decline. In addition, although thymopoietic efficiency was increased in both groups of Ox rats when compared with age-matched controls, thymopoiesis exhibited the age-related decline mirrored in the lower numbers of both CD4+ and CD8+ recent thymic emigrants in peripheral blood. This reflected the prethymic changes affecting bone marrow progenitor generation/entry and the thymic alterations encompassing the impaired progenitor progression through early pre-T-cell receptor developmental stages (defined by CD45RC/CD2 expression) and, possibly, a more pronounced decrease in the proliferation of the most mature thymocytes. Apart from the changes at thymocyte level, in Ox rats the age-related alterations in thymic stroma (substantiated in a prominent loss of thymic epithelial cells) were registered. Ovariectomy-induced changes in thymic lymphoid and epithelial component, most probably, influenced each other leading to the increase in thymic expression of interleukin-6 and interleukin-7 mRNAs along with time after ovariectomy. Collectively, the study showed that the withdrawal of ovarian hormones in prepubertal age increases the efficiency of thymopoiesis in young adult rats, but does not prevent decline in thymopoiesis occurring with age
Biochemical and immunological characterization of a recombinantlyproduced antifungal cysteine proteinase inhibitor from green kiwifruit (Actinidia deliciosa)
No full textPlant proteinase inhibitors are considered important defense molecules against insect and pathogen attack. The cysteine proteinase inhibitor (CPI) from green kiwifruit (Actinidia deliciosa) belongs to the cystatin family and shows potent antifungal activity (in vitro and in vivo). However, the low abundance of this molecule in fruit (6 μg/g of fresh fruit) seems to limit further investigations on the interaction between phytocystatin and photopathogenic fungi. In this paper the cDNA of the kiwi CPI was expressed in Escherichia coli. Fifteen N-terminal amino acids were identified by Edman degradation, and 77% of the rCPI primary structure was confirmed by mass fingerprint. The structural homology of recombinant CPI (rCPI) to its natural counterpart has been clearly demonstrated in immunological assays (immunoblot and ELISA inhibition). Biological activity of rCPI was demonstrated in inhibition assay with cysteine proteinase papain (EC50 2.78 nM). In addition, rCPI reveals antifungal properties toward pathogenic fungi (Alternaria radicina and Botrytis cinerea), which designates it as an interesting model protein for the exploration of plant phytocystatins - pathogen interactions. Understanding the molecular mechanisms of natural plant resistance could lead to the development of ecologically safe fungicides for controlling postharvest diseases and maintaining food quality
Adrenal hormone deprivation affects macrophage catecholamine metabolism and 2-adrenoceptor density, but not propranolol stimulation of tumour necrosis factor- production
No full textNew Findings center dot What is the central question of this study? Glucocorticoids modulate extraglandular catecholamine metabolism and adrenoceptor expression in many cell types. Catecholamines modulate the production of inflammatory mediators by macrophages. It was hypothesized that adrenal hormones affect tumour necrosis factor- production in rat macrophages by altering the autocrine/paracrine action of catecholamines. center dot What is the main finding and its importance? In rat macrophages, adrenalectomy increased tyrosine hydroxylase expression, decreased monoamine oxidase-A mRNA expression (due to the absence of adrenal catecholamines and glucocorticoids, respectively) and augmented 2-adrenoceptor expression (due to lack of adrenal catecholamines). However, notwithstanding these changes, propranolol treatment increased lipopolysaccharide-stimulated tumour necrosis factor- production in macrophages from adrenalectomized and non-operated rats to a similar extent. Catecholamines modulate the production of inflammatory mediators by macrophages in an autocrine/paracrine manner. They also tune 2-adrenoceptor expression. Glucocorticoids influence catecholamine metabolism and adrenoceptor expression in many cell types. We hypothesized that adrenal hormones affect the production of tumour necrosis factor- (TNF-) and NO by macrophages by altering the modulatory influence of catecholamines. To prove the hypothesis, peritoneal exudate macrophages from propranolol-treated non-operated and adrenalectomized rats and from corticosterone-supplemented adrenalectomized rats were examined for lipopolysaccharide-stimulated NO and TNF- production in vitro and for expression of 2-adrenoceptors and major catecholamine-metabolizing enzymes. Glucocorticoid deprivation increased NO production by macrophages, whereas 4 days of propranolol treatment was ineffective in this respect. However, propranolol treatment, via 2-adrenoceptor blockade, increased production of TNF- by macrophages in both non-operated and adrenalectomized rats (showing dramatically enhanced TNF- production due to a lack of circulating glucocorticoids) for the same value. The expression of 2-adrenoceptor was increased in peritoneal macrophages that were freshly isolated from non-operated, propranolol-treated and adrenalectomized rats (due to adrenal catecholamine deficiency). Propranolol did not affect macrophage 2-adrenoceptor expression in adrenalectomized rats. Given that propranolol increased the density of macrophage tyrosine hydroxylase expression only in non-operated rats and affected the mRNA expression of monoamine oxidase-A in neither non-operated nor adrenalectomized animals, a significant influence of propranolol on peritoneal exudate cell noradrenaline content was found only in non-operated rats. A lack of circulating adrenal hormones also affected noradrenaline metabolism and content in peritoneal exudate cells including macrophages. Collectively, despite differences in the abundance of macrophage catecholamine2-adrenoceptor system components and in the TNF- response to lipopolysaccharide between adrenalectomized and non-operated rats, propranolol increased TNF- production by the same amount in macrophages from these two groups of animals
One-step method for isolation and purification of native beta-lactoglobulin from bovine whey
No full textBACKGROUND: The major whey protein beta-lactoglobulin (BLG) has been widely studied for its functional properties. The aim of this study was to develop an efficient, inexpensive and rapid one-step method for the isolation and purification of BLG while preserving its native structure. RESULTS: BLGwas purified fromdefattedwheyobtainedfromrawcow's milkbyanionexchangechromatography. Protein purity and identitywere determined using reverse phase high-performance liquid chromatography andmass spectrometry. Total BLG yield was 80% with protein purity from 97 to 99%. BLG isoforms A and B were separated into fractions of 91 and 99% purity respectively. The structure and native conformation of the isolated BLGwere compared with those of standard commercial BLG by circular dichroism spectrometry, susceptibility to various crosslinking enzymes and enzyme-linked immunosorbent assay inhibition. CONCLUSION: Theproposedmethodis veryuseful for the rapid preparationofBLGsuitable for studying antigenicandmolecular characteristics of this protein, aswell as the effect of food processing on these properties. The procedure requires only 1 day for the purification of about 300 mgof BLG from a single run using a small column (2.5 cmx20 cm) of diethylaminoethyl Sephadex and has potential for scaling up. (C) 2011 Society of Chemical IndustryPeer-reviewed manuscript: [http://intor.torlakinstitut.com/handle/123456789/675
Induction of decreased fecundity by tetanus toxoid hyper-immunization in C57BL/6 mice depends on the applied adjuvant
No full textIt has already been shown that tetanus toxoid (TTd) hyper-immunization is a suitable experimental method for creating the animal model of antiphospholipid syndrome (APS) in BALB/c mice. The severity of APS pathology in BALB/c mice mainly correlates to the affinity of anti-beta(2) glycoprotein I (beta(2)GPI) antibodies. In this study we have investigated reproductive pathology induced in C57BL/6 mice by TTd hyper-immunization using a combination of different pretreatments (complete Freund's adjuvant or glycerol) and adjuvants (alhydrogel or glycerol). A decrease in fecundity was recorded in only C57BL/6 mice immunized with alhydrogel adjuvant, irrespective of the kind of applied pretreatment; it was associated with an increase in abundance of low affinity anti-beta(2)GPI IgG antibodies and Th1 prevalence
Vaccine model of antiphospholipid syndrome induced by tetanus vaccine
No full textSuccessful induction of antiphospholipid syndrome (APS) in two different non-autoimmune prone mouse strains, BALB/c and C57BL/6, was achieved by tetanus toxoid (TTd) hyperimmunization using different adjuvants (glycerol or aluminium hydroxide), and different adjuvant pretreatments (glycerol or Complete Freund's Adjuvant (CFA)). APS had different manifestations of reproductive pathology in BALB/c and C57BL/6 mice: fetal resorption (as a consequence of extreme T-cell activation obtained in the course of pretreatment), and lowering of fecundity (as a consequence of polyclonal B-cell stimulation), respectively. In BALB/c mice fetal resorption coincided with glycerol and CFA pretreatments, while in C57BL/6 mice lowering of fecundity was most obvious in CFA-pretreated mice immunized with TTd in aluminium hydroxide. Both molecular mimicry and polyclonal B-cell activation occur in APS induction, with molecular mimicry effects being dominant in BALB/c mice, and polyclonal cell activation being dominant in C57BL/6 mice. Confirmation of molecular mimicry effects, which in the condition of T-cell stimulation generated fetal resorptions in the BALB/c strain, was achieved by passive infusion of monoclonal antibody (MoAb) T-26 specific for TTd and anti-beta(2)-glycoprotein I obtained after TTd hyperimunization. High polyclonal B-cell activation in C57BL/6 mice prevented fetal resorption but induced fecundity lowering, as was the case in passive administration of MoAb T-26 in this mouse strain. Passive infusion of anti-idiotypic MoAb Y7 into C57BL/6 mice induced fetal resorptions and confirmed the above suggestion on the protective role of polyclonal B-cell stimulation in fetal resorptions. Lupus (2012) 21, 195-202
Recombinant banana lectin as mucosal immunostimulator
No full textTo explore the potential usage of recombinant banana lectin as an immunostimulator it was of interest to analyze the effect it exerted in vivo in mice, upon two different routes of exposure. By Western blotting analysis of the gastric and intestinal luminal content it was found that recombinant banana lectin is stable in vivo in the mouse digestive tract, where it specifically interacts with the mucosal surfaces which can be inhibited by the addition of glucose. Its attachment to mice jejunum has been confirmed by immunofluorescence. In addition, it was able to induce systemic immunity, evidenced by specific antibody production, by oral application, a property that might be exploited for the induction of systemic immune responses. (c) 2012 Elsevier Ltd. All rights reserved