Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 57
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Sci Rep ; 11(1): 22944, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34824322

RESUMO

A unique combination of the ultrashort high-energy pulsed laser system with exceptional beam quality and a novel Diffractive Optical Element (DOE) enables simultaneous production of 2601 spots organized in the square-shaped 1 × 1 mm matrix in less than 0.01 ms. By adjusting the laser and processing parameters each spot can contain Laser Induced Periodic Surface Structures (LIPSS, ripples), including high-spatial frequency LIPSS (HFSL) and low-spatial frequency LIPSS (LSFL). DOE placed before galvanometric scanner allows easy integration and stitching of the pattern over larger areas. In addition, the LIPSS formation was monitored for the first time using fast infrared radiometry for verification of real-time quality control possibilities. During the LIPSS fabrication, solidification plateaus were observed after each laser pulse, which enables process control by monitoring heat accumulation or plateau length using a new signal derivation approach. Analysis of solidification plateaus after each laser pulse enabled dynamic calibration of the measurement. Heat accumulation temperatures from 200 to 1000 °C were observed from measurement and compared to the theoretical model. The temperature measurements revealed interesting changes in the physics of the laser ablation process. Moreover, the highest throughput on the area of 40 × 40 mm reached 1910 cm2/min, which is the highest demonstrated throughput of LIPSS nanostructuring, to the best of our knowledge. Thus, showing great potential for the efficient production of LIPSS-based functional surfaces which can be used to improve surface mechanical, biological or optical properties.

2.
Folia Biol (Praha) ; 65(5-6): 221-226, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32362305

RESUMO

Due to the increasing incidence of allergic diseases, there is a strong need to identify a prognostic marker pointing to increased risk of allergy development allowing introduction of early preventive measures. Cord blood seems to be a good source for searching for such marker. The capacity of cord blood cells to respond to common allergens could point to increased predisposition to later allergy development. In our study, cytokines typical of Th1 (IFN-γ), Th2 (IL-5, IL-13) and Treg (IL-10) immune responses were followed at both the level of gene expression and cytokine secretion in cord blood cells of newborns of healthy mothers (children with relatively low risk of allergy development) and allergic mothers (children with relatively high risk of allergy development) stimulated by allergens (pollen from birch and timothy grass, house dust mite, ovalbumin). We have not observed any difference in the response of cord blood cells of neonates of healthy and allergic mothers to allergen in vitro. Both gene expression and secretion of cytokines in response to allergen stimulation were comparable with the unstimulated controls. It seems that early postnatal events will be more decisive for future allergy development than prenatal sensitization of the foetal immune system with allergen in utero in allergic mothers.


Assuntos
Alérgenos/imunologia , Hipersensibilidade/imunologia , Imunidade , Mães , Criança , Citocinas/genética , Citocinas/metabolismo , Feminino , Sangue Fetal/citologia , Regulação da Expressão Gênica , Humanos , Hipersensibilidade/genética , Recém-Nascido , Leucócitos Mononucleares/metabolismo
3.
Benef Microbes ; 7(5): 639-648, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27633175

RESUMO

Probiotics are believed to prevent or reduce allergy development but the mechanism of their beneficial effect is still poorly understood. Immune characteristics of regulatory T cells (Tregs) in peripheral blood of perinatally probiotic-supplemented children of allergic mothers (51 children), non-supplemented children of allergic mothers (42 children), and non-supplemented children of healthy mothers (28 children) were compared at the age of 6-7 years. A first dose of a probiotic Escherichia coli strain (E. coli O83:K24:H31) was administered within 2 days after the birth and then 12 times during the first months of life and children were followed longitudinally. Proportion and functional properties of Tregs were estimated by flow cytometry in relation to the children's allergy status. Proportion of Tregs in the peripheral blood of children suffering from allergy tends to be higher whereas median of fluorescence intensity (MFI) of FoxP3 was significantly decreased in allergic group. Intracellular presence of regulatory cytokine interleukin (IL)-10 was also lower in allergic children. Immune functions of Tregs reflected by both MFI of FoxP3 and IL-10 in the group of probiotic-supplemented children of allergic mothers were nearly comparable with children of healthy mothers while probiotic non-supplemented children of allergic mothers have decreased immune function of Tregs. Supplementation by probiotic E. coli strain decreases allergy incidence in high-risk children. In contrast to our expectation, proportion of Tregs has not been increased in probiotic supplemented children. Beneficial effect of probiotics on newborn immature immune system could be, at least partially, explained by the modulating immune function of Tregs. In summary, we detected increased proportion of Tregs in peripheral blood of allergic children, their functional properties were decreased in comparison with the Tregs of healthy children. A unifying hypothesis for these findings is that Treg numbers in allergic children are increased in order to compensate for decreased function.


Assuntos
Citocinas/imunologia , Escherichia coli , Hipersensibilidade/prevenção & controle , Interleucina-10/imunologia , Probióticos/administração & dosagem , Linfócitos T Reguladores/imunologia , Criança , Pré-Escolar , Citocinas/sangue , Feminino , Citometria de Fluxo , Humanos , Lactente , Recém-Nascido , Interleucina-10/sangue , Masculino
4.
Folia Biol (Praha) ; 60(2): 74-82, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24785110

RESUMO

The incidence of allergic diseases is steadily increasing an urgent need to clarify the immunologic processes which occur early in life and signal an increased risk of possible future allergy development. The ratio and maturation state of DCs together with the cytokine environment are important in directing and modulating immune responses. The maturation state (presence of CD83) of cord blood monocyte-derived dendritic cells (moDCs) of 52 children of healthy mothers and 58 children of allergic mothers was estimated by flow cytometry. The capacity of moDCs to express genes for subunits of IL-12 family cytokines was monitored using real-time PCR and protein secretion in cell culture supernatants by ELISA. The percentage of CD83+ moDCs was significantly higher in the allergic group after LPS stimulation (43.11 ± 4.41) in comparison to the healthy group (24.85 ± 3.37). Significantly higher gene expression of subunits of IL-12 family members was observed in moDCs of children of allergic mothers, in comparison with children of healthy mothers. The differences were evident mainly after LPS stimulation of moDCs (healthy group: p19: 3.05 ± 1.24; p28: 14.8 ± 6.8; p35: 1.8 ± 0.6; p40: 8.0 ± 3.5; EBI3: 3.0 ± 1.2; allergic group: p19: 6.1 ± 2.7; p28: 61.4 ± 22.2; p35: 14.9 ± 6.5; p40: 36.4 ± 18.8; EBI3: 11.3 ± 3.2), with the exception of p28, whose expression was significantly higher in the allergic group even without stimulation (healthy group: 0.28 ± 0.12, allergic group: 0.87 ± 0.62). No significant difference between the healthy and allergic groups was found at the protein level. The observation of both increased presence of cell surface activation marker on moDCs and higher IL-12 family gene expression in LPS-stimulated moDCs of children of allergic mothers indicates a higher reactivity of these cells.


Assuntos
Células Dendríticas/metabolismo , Sangue Fetal/citologia , Interleucina-12/metabolismo , Antígenos CD , Células Cultivadas , Feminino , Citometria de Fluxo , Humanos , Hipersensibilidade/etiologia , Hipersensibilidade/metabolismo , Imunoglobulinas , Lipopolissacarídeos/farmacologia , Masculino , Glicoproteínas de Membrana , Mães , Antígeno CD83
5.
Clin Exp Immunol ; 170(1): 10-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22943196

RESUMO

Allergy is one of the most common diseases with constantly increasing incidence. The identification of prognostic markers pointing to increased risk of allergy development is of importance. Cord blood represents a suitable source of cells for searching for such prognostic markers. In our previous work, we described the increased reactivity of cord blood cells of newborns of allergic mothers in comparison to newborns of healthy mothers, which raised the question of whether or not this was due to the impaired function of regulatory T cells (T(regs)) in high-risk children. Therefore, the proportion and functional properties of T(regs) in cord blood of children of healthy and allergic mothers were estimated by flow cytometry. The proportion of T(regs) [CD4(+)CD25(high)CD127(low) forkhead box protein 3 (FoxP3(+))] in cord blood of children of allergic mothers tends to be higher while, in contrast, the median of fluorescence intensity of FoxP3 was increased significantly in the healthy group. Intracellular presence of regulatory cytokines interleukin (IL)-10 and transforming growth factor (TGF)-beta was also higher in T(regs) of children of healthy mothers. Although we detected an increased proportion of T(regs) in cord blood of children of allergic mothers, the functional indicators (intracellular presence of regulatory cytokines IL-10 and TGF-beta, median of fluorescence intensity of FoxP3) of those T(regs) were lower in comparison to the healthy group. We can conclude that impaired function of T(regs) in cord blood of children of allergic mothers could be compensated partially by their increased number. Insufficient function of T(regs) could facilitate allergen sensitization in high-risk individuals after subsequent allergen encounter.


Assuntos
Sangue Fetal/imunologia , Fatores de Transcrição Forkhead/metabolismo , Hipersensibilidade/imunologia , Linfócitos T Reguladores/imunologia , Antígenos CD4/metabolismo , Estudos de Casos e Controles , Feminino , Sangue Fetal/citologia , Sangue Fetal/metabolismo , Citometria de Fluxo , Fatores de Transcrição Forkhead/imunologia , Humanos , Hipersensibilidade/sangue , Recém-Nascido , Interleucina-10/sangue , Interleucina-10/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Gravidez , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/sangue , Fator de Crescimento Transformador beta/metabolismo
6.
Folia Microbiol (Praha) ; 55(5): 515-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20941589

RESUMO

To determine some early signs connected with the increased risk of future allergy development, gene expression and production of selected cytokines were tested in children of allergic mothers and compared with newborns of healthy mothers. Expression of IL-1ß, IL-2, IL-4, IL-8, IL-10, IL-13, IFN-γ, TNF-α, TGF-ß and EGF was tested in cord blood cells using real-time PCR and production of these cytokines was evaluated in cord sera by ELISA. Gene expression of IL-2, IL-4, IL-8, IFN-γ, IL-1ß, TNF-α and TGF-ß was decreased and that of IL-10, IL-13 and EGF increased in children of allergic mothers in comparison with those of healthy mothers. Significant differences in sera of healthy and allergic groups were only in IL-10 and EGF. Different relationship among serum cytokine levels reflects the fact that the cytokines are not produced only by blood cells. Significantly decreased production of EGF in newborns of allergic mothers could negatively influence maturation of mucosal membranes of these children and support thus their easier allergization. Allergic phenotype pointing to the bias to T(H)2 response and to possibly impaired intestine maturation was apparent already on the level of cord blood and could serve as a predictive sign of increased allergy risk.


Assuntos
Citocinas/sangue , Sangue Fetal/citologia , Sangue Fetal/metabolismo , Hipersensibilidade/sangue , Citocinas/genética , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Fator de Crescimento Epidérmico/sangue , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/metabolismo , Feminino , Expressão Gênica , Humanos , Recém-Nascido , Interleucina-10/sangue , Interleucina-10/genética , Interleucina-10/metabolismo , Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Physiol Res ; 58(3): 419-425, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18637715

RESUMO

Knowledge on the involvement of spinal COX-1 and COX-2 in pain due to osteoarthritis could be useful for better understanding of its pathogenesis and therapy. In this study we have investigated a long-term pattern of expression and production of spinal COX-1 and COX-2 in the model of osteoarthritis induced in rats by injection of monoiodoacetate (MIA) into the knee joint. MIA injection produced thermal hyperalgesia (assessed by the plantar test) and tactile allodynia (measured with von Frey hairs). The pain measures reached maximum on the fifht day, then remained relatively stable. The expression of spinal COX-2 mRNA reached maximum on day 5 (5.2 times; P<0.001) and remained increased until day 31 (4.9 times; P<0.001). Expression of spinal COX-1 mRNA increased gradually reaching maximum on the day 31 (4.5 times; P<0.001) when the relative expression of both genes was almost equal. The production of both proteins was almost similar at the beginning of the experiment. The highest production of COX-2 protein was observed on day 5 after the induction of osteoarthritis (increased 3.9 times). The levels of COX-1 protein increased gradually with maximum on day 31 (3.4 times). The present findings indicate that not only expression of COX-2 mRNA but also that of COX-1 mRNA is significantly increased in the spine during osteoarthritis pain. Thus, in contrast to inflammatory pain, the upregulation of spinal COX-1 may be important in osteoarthritis pain.


Assuntos
Ciclo-Oxigenase 1/biossíntese , Ciclo-Oxigenase 2/biossíntese , Hiperalgesia/enzimologia , Proteínas de Membrana/biossíntese , Osteoartrite do Joelho/enzimologia , Dor/enzimologia , Medula Espinal/enzimologia , Animais , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 2/genética , Modelos Animais de Doenças , Indução Enzimática , Hiperalgesia/induzido quimicamente , Hiperalgesia/genética , Ácido Iodoacético , Masculino , Proteínas de Membrana/genética , Osteoartrite do Joelho/induzido quimicamente , Osteoartrite do Joelho/genética , Dor/induzido quimicamente , Dor/genética , Medição da Dor , Limiar da Dor , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Tempo de Reação , Fatores de Tempo
8.
Folia Microbiol (Praha) ; 54(6): 549-52, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20140725

RESUMO

Intratracheal immunization of mice with inactivated influenza B virus and delipidated Bacillus firmus as adjuvant increases protection of mice against infection with the homologous virus strain and induces cross-protection: mice immunized by influenza virus B/Yamanashi 166/98 were protected even against phylogenetically distant virus drift variant B/Lee/40 lethal for mice.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Imunização/métodos , Vírus da Influenza B/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Administração por Inalação , Animais , Bacillus/imunologia , Proteção Cruzada , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Análise de Sobrevida , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia
9.
Folia Microbiol (Praha) ; 53(1): 67-72, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18481221

RESUMO

IgE against mixtures of common food or respiratory allergens were determined by ELISA in healthy (n = 38) and allergic (n = 62) mothers and their children. Significantly higher level of IgE against respiratory allergens was found in sera of allergic mothers and in cord blood of their children. No correlation between antibody level in maternal and newborn's sera was found; this argues against the transfer of IgE from mother to fetus and points rather to offspring's intrauterine sensitization. Specific IgE level in cord blood was higher in children who developed later allergy than in children who did not. Specific IgE level in colostrum was low both in healthy and allergic mothers; there was no correlation between high concentration of IgE against respiratory allergens in sera of allergic mothers and their colostrum, which does not support the idea of IgE transport from blood to mammary gland. Only slightly increased colostral IgE was detected in allergic mothers whose children manifested allergy later. Allergy of the mother and high level of anti-allergen IgE in her serum and in cord blood are the main predictive factors of future occurrence of allergy in the offspring. A combination of several predictive factors could have higher prognostic value.


Assuntos
Hipersensibilidade Alimentar/imunologia , Imunoglobulina E/análise , Hipersensibilidade Respiratória/imunologia , Colostro/imunologia , Feminino , Sangue Fetal/imunologia , Seguimentos , Hipersensibilidade Alimentar/etiologia , Humanos , Hipersensibilidade , Imunoglobulina E/sangue , Lactente , Masculino , Troca Materno-Fetal , Leite Humano/imunologia , Mães , Gravidez , Hipersensibilidade Respiratória/etiologia
10.
Folia Microbiol (Praha) ; 52(5): 549-55, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18298055

RESUMO

Testing of cytokine levels in colostrum, cord blood and amniotic fluid of healthy and allergic mothers and their newborns (using protein microarrays and quantitative analysis by ELISA) revealed differences in the levels of IL-5, IL-10, TGF-beta, TNF-alpha, EGF and eotaxin between healthy and allergic groups. Significantly higher concentration of IL-5 and IL-10 in the colostrum of allergic mothers and cord blood of their children and also tendency to a higher level of IL-4 found at allergic mothers and their children (but without statistical significance) indicate a bias to T(H)2 response in this group. The higher level of TGF-beta in the colostrum of healthy mothers should be involved in beneficial immunological tuning of their children including enhanced IgA formation and better intestine maturation. In amniotic fluid, concentration of TGF-beta was higher in children of allergic mothers. A significantly higher level of EGF was proved in the colostrum of healthy mothers and in cord blood of their children in comparison with allergic group. EGF deficiency in the allergic group could impair or delay intestine maturation and support thus allergy development.


Assuntos
Citocinas/imunologia , Hipersensibilidade/diagnóstico , Hipersensibilidade/imunologia , Líquido Amniótico/imunologia , Colostro/imunologia , Colostro/metabolismo , Citocinas/sangue , Ensaio de Imunoadsorção Enzimática , Fator de Crescimento Epidérmico/sangue , Feminino , Sangue Fetal/imunologia , Humanos , Hipersensibilidade/sangue , Recém-Nascido , Gravidez , Prognóstico , Análise Serial de Proteínas/métodos , Medição de Risco
11.
Folia Microbiol (Praha) ; 51(3): 243-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17004658

RESUMO

The effect of nonpathogenic G+ bacterium B. firmus (BF) on stimulation of mouse peritoneal cells in vitro was evaluated by testing nitric-oxide-synthesis induction and cytokine formation. The reactivity was compared of peritoneal cells from two inbred mouse strains, C57B1/6 and BALB/c, which differ in their immunological reactivity. Peritoneal macrophages from C57B1/6 produced more nitric oxide after a 1-d cultivation with inactivated BF than those of BALB/c mice. In both strains, production can be further increased by adding exogenous IFN-gamma to the culture. There were no significant differences between peritoneal cells of these two mouse strains in cytokine production after optimal in vitro stimulation with BF. BF effectively activated peritoneal cells for the production of TNF-alpha, IL-1beta and IL-10, delipidated bacterium (DBF) being more efficient than BF in induction of IL-10 and TNF-alpha. On the other hand, BF had only small effect on IFN-gamma production and no detectable effect on IL-12 production. Macrophage activation by BF/DBF can represent one of the mechanisms responsible for previously described immunomodulatory activity of BF.


Assuntos
Bacillus/imunologia , Citocinas/imunologia , Ativação de Macrófagos , Óxido Nítrico/metabolismo , Cavidade Peritoneal/citologia , Animais , Técnicas de Cultura de Células/métodos , Citocinas/metabolismo , Feminino , Imunidade Inata , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Compostos Orgânicos/farmacologia
12.
Folia Microbiol (Praha) ; 51(2): 154-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16821727

RESUMO

Intranasal immunization of guinea pigs with inactivated type B influenza virus plus inactivated Bacillus firmus as an adjuvant compared to the virus alone yields higher titers of serum hemagglutination-inhibiting antibodies and virus-neutralizing antibodies. This phenomenon could be useful in standard serology, especially in the preparation of immune sera against highly pathogenic strains for in vitro diagnosis.


Assuntos
Adjuvantes Imunológicos , Bacillus/imunologia , Vírus da Influenza B/imunologia , Vacinas contra Influenza/imunologia , Vacinação/métodos , Animais , Anticorpos Antivirais/análise , Cobaias , Testes Sorológicos/métodos
13.
Folia Microbiol (Praha) ; 50(3): 247-53, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16295664

RESUMO

Inactivated Bacillus firmus (BF), G+ nonpathogenic bacterium of the external environment, was coupled to ovalbumin (OVA) and used in immunization experiments as antigen carrier. Balb/c mice were immunized thrice intra-tracheally and intra-nasally with conjugates of OVA and BF. Surprisingly, administration of OVA-BF conjugates inhibited anti-OVA IgG response in both sera and mucosal secretions if compared to an exposure to OVA alone. The suppression of antigen-specific antibody production was accompanied by promotion of TH1 phenotype.


Assuntos
Antígenos/administração & dosagem , Bacillus/imunologia , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Administração Intranasal , Animais , Anticorpos Antibacterianos/biossíntese , Anticorpos Antibacterianos/sangue , Portadores de Fármacos , Feminino , Imunidade nas Mucosas , Imunização , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Técnicas In Vitro , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Células Th1/imunologia , Traqueia
14.
Immunol Lett ; 97(2): 251-9, 2005 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15752565

RESUMO

Satisfactory mucosal immunity in the respiratory tract is very important for protection against influenza. It can be achieved only by mucosal immunization. Mucosal vaccination with inactivated influenza virus may not be sufficiently effective and suitable adjuvants are therefore sought. We tested intratracheal immunization of mice with inactivate B type influenza virus in a mixture with formolized G+ bacterium Bacillus firmus, whose adjuvant effects have previously been documented in another system. The treatment resulted in a marked increase of both systemic and mucosal antibody response in IgG and IgA classes. Stimulation of T lymphocytes after adjuvant immunization was very mild, no proliferation taking place after specific stimulation with antigen in vitro. However, slightly increased systemic (spleen) and local (lungs) production of cytokines without perceptible Th1/Th2 polarization was determined. B. firmus is an efficient adjuvant in respiratory tract immunization while with subcutaneous immunization it lowers the antibody response.


Assuntos
Adjuvantes Imunológicos , Betainfluenzavirus/imunologia , Imunidade nas Mucosas/imunologia , Vacinas contra Influenza/imunologia , Vacinas de Produtos Inativados/imunologia , Inativação de Vírus , Animais , Anticorpos Antivirais/análise , Anticorpos Antivirais/imunologia , Linhagem Celular , Citocinas/biossíntese , Citocinas/genética , Citocinas/imunologia , Cães , Ensaio de Imunoadsorção Enzimática , Feminino , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Ativação Linfocitária , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Testes de Neutralização , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Linfócitos T/imunologia
15.
Ceska Gynekol ; 69 Suppl 1: 91-7, 2004 Dec.
Artigo em Tcheco | MEDLINE | ID: mdl-15748033

RESUMO

OBJECTIVE: prevention of repeated infections and allergies in children of allergic mothers by oral colonization with probiotic E. coli strain.The development of some immunologic parameters. Long - term studies. DESIGN: Original contribution SETTING: Mother and Child Care Institute of Prague. METHODS AND RESULTS: The results of our long-term studies confirmed that orally administered probiotic E. coli strain after birth rapidly colonized the gastrontestinal tract of the newborn and remained dominant for many weeks. The long-term presence of the strain in the intestine stimulated local and serum antibody response. Early induction of secretory IgA production is important particularly in formula-fed infants. The long-term presence of the E. coli strain in the intestine decreased the numer of pathogens colonizing intestinal and other mucous membranes , the frequency of infections and reduced need for antibiotics in premature and high-risk infants. Ten years later, there was still a lower frequency of repeated infections (23%) in comparison with control children (58%). Colonization with probiotic E. coli strain in infants treated in protected (pathogen-free) environment represented effective prevention of nosocomial infections In the colonized group infections occured in 16% of infants and 130 isolates and 7 genera of pathogens were demonstrated. In the group treated in conventional environment 40% of infants had nosocomial infections, 238 isolates and 10 genera of pathogens were proved. The hospitalization period was shorter in the first group (26 versus 34 days). Intentional colonization with probiotic E. coli after birth reduced incidence of allergies after 10 and 20 years (being 12% and 16% in the colonized groups and 33 and 32% in controls). In the present long - term study (evaluated after the first year) colonization with vaccine COLINFANT after birth influenced the levels of some cytokines ( IL-4, IFN-gama,TGF-beta) and also clinical manifestation of allergy (there were no signs of allergy in colonized infants of allergic mothers, but 25% of infants of control allergic mothers had clinical manifestations of allergies). CONCLUSIONS: By replacement of the natural but incidental ( event. pathogenic ) colonization of the intestine by a targeted orally administered E. coli strain after birth we may have come upon the possibility of how to prevent nosomial infections particularly in formula-fed and high-risk infants and prevent occurence of allergies in infants of allergic mothers.


Assuntos
Infecções Bacterianas/prevenção & controle , Citocinas/sangue , Escherichia coli , Hipersensibilidade/prevenção & controle , Probióticos/administração & dosagem , Administração Oral , Infecção Hospitalar/prevenção & controle , Escherichia coli/crescimento & desenvolvimento , Seguimentos , Trato Gastrointestinal/microbiologia , Humanos , Imunoglobulina A Secretora/análise , Recém-Nascido
16.
Folia Microbiol (Praha) ; 48(3): 427-34, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12879759

RESUMO

Functions of T cells were determined after intranasal and intratracheal immunization of mice with ovalbumin (Ova) and Bacillus firmus (Bf), a Gram-positive nonpathogenic bacterium of the external environment, or delipidated Bf (dBf) as adjuvants, with the aim to elucidate the mechanism of support of Ova-specific antibody production caused by Bf that had been observed in an identical experiment. Neither Bf nor dBf in a mixture with Ova stimulated Ova-specific T-cell response tested as antigen-specific blast transformation. By contrast, a mild polyclonal stimulation was observed in splenocytes from mice given dBf. In vitro incubation of splenocytes with 100 micrograms (but not 10 micrograms) of Bf or dBf led to a highly significant inhibition of proliferation below the control level in all groups of animals. Supernatants of splenocyte cultures were further tested for cytokine production. IL-10 and IFN-gamma were released after in vitro challenge with dBf and in some cases also with Bf. Analysis of sera demonstrated that administration of Ova + adjuvant brought about an increase in anti-Ova IgG1, IgG2a and IgG2b whereas treatment with Ova alone caused a rise in IgG1 only. The role of Bf or dBf in the enhancement of antigen-specific antibody production could be in influencing macrophages and inducing cytokine milieu composed of IL-10, IFN-gamma and other factors that leads to a bystander stimulation of specifically activated Ova-B cell receptor (Ova-BCR)-bearing cells.


Assuntos
Adjuvantes Imunológicos/farmacologia , Bacillus/imunologia , Ovalbumina/imunologia , Linfócitos T/imunologia , Adjuvantes Imunológicos/administração & dosagem , Administração Intranasal , Animais , Citocinas/imunologia , Citocinas/metabolismo , Feminino , Imunização/métodos , Imunização/normas , Imunoglobulina G/sangue , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/administração & dosagem
17.
Folia Microbiol (Praha) ; 47(2): 193-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12058402

RESUMO

Bacillus firmus (a Gram-positive nonpathogenic and harmless bacterium), was shown to be a strong polyclonal activator of mouse B lymphocytes as estimated by ELISA testing of Ig concentrations in culture supernatants after incubation of BALB/c mouse splenocytes with inactivated bacillus. Synthesis of all main Ig classes and all IgG subclasses was stimulated in vitro, the considerable effect on IgA formation being the most interesting feature. B cell stimulation was T cell dependent, as was demonstrated by the effect of B. firmus on all Ig isotypes and by comparison of lymphocyte response of nu/nu mice and heterozygous nu/+ mice. The effect of B. firmus on splenocyte proliferation was stimulatory or suppressive depending on the dose of the bacterium. Increased synthesis of IFN-gamma and IL-10 (detected by ELISA in splenocyte culture supernatants) showed probable stimulation of Th1 and Th2 subpopulations. Considering the stimulatory effect on IgA formation and macrophage stimulation, B. firmus seems to be a prospective mucosal adjuvant and/or probiotic.


Assuntos
Linfócitos B/imunologia , Bacillus/imunologia , Imunoglobulina G/biossíntese , Ativação Linfocitária , Linfócitos T/imunologia , Animais , Anticorpos Antibacterianos/biossíntese , Linfócitos B/efeitos dos fármacos , Bacillus/química , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Imunoglobulina G/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C
18.
Folia Microbiol (Praha) ; 47(6): 759-65, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12630333

RESUMO

A nonpathogenic bacterium of external environment possessing remarkable immunomodulatory activity, Bacillus firmus (BF) inactivated with formaldehyde, was given intragastrically to two genetically different mouse strains BALB/c (H-2d) and B10.BR/SnPh (B10.BR, H-2k) reared in conventional (CV) and B10.BR strain also in germ-free (GF) conditions. Repeated intragastric administration of BF (500 micrograms every other day over two weeks, starting at the age of 3 months) significantly enhanced intestinal IgA levels in CV BALB/c mice but did not affect intestinal IgA in CV B10.BR mice. In GF B10.BR mice, IgG levels in sera and intestinal washings increased after BF administration compared to CV B10.BR mice. In CV BALB/c mice, specific activity of enterocyte brush-border enzymes (lactase, gamma-glutamyltransferase, alkaline phosphatase) decreased after BF treatment; sucrase (sucrose alpha-glucosidase) activity was not affected. On the other hand, in B10.BR mice, specific activity of gamma-glutamyltransferase and dipeptidyl peptidase IV were higher after administration of BF in both CV and GF groups relative to untreated controls. The activities of lactase and glucoamylase (glucan 1,4-alpha-glucosidase) were significantly stimulated only in the group of GF B10.BR mice treated with formolized BF. The stimulation of immunoglobulin production after BF treatment was accompanied by changes in the levels of enterocyte brush-border enzymes; this responsiveness to BF treatment was genetically regulated.


Assuntos
Bacillus/imunologia , Intestinos/imunologia , Intestinos/microbiologia , Fosfatase Alcalina/metabolismo , Animais , Dipeptidil Peptidase 4/metabolismo , Enterócitos/enzimologia , Enterócitos/microbiologia , Feminino , Predisposição Genética para Doença , Vida Livre de Germes , Glucana 1,4-alfa-Glucosidase/metabolismo , Imunoglobulina A/biossíntese , Imunoglobulina A/sangue , Imuno-Histoquímica , Mucosa Intestinal/enzimologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Intestinos/enzimologia , Lactase , Camundongos , Camundongos Endogâmicos BALB C , Microvilosidades/enzimologia , Sacarase/metabolismo , beta-Galactosidase/metabolismo
19.
Immunol Lett ; 77(1): 39-45, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11348668

RESUMO

Bacillus firmus, a non-pathogenic Gram positive (G+) bacterium of the external environment was investigated for immunomodulatory properties. It stimulated an increase in anti-ovalbumin IgG in sera, bronchoalveolar lavages and intestinal washings after both intranasal (i.n.) and intratracheal (i.t.) immunisation, and enhanced anti-ovalbumin IgA in intestinal secretions and in bronchoalveolar lavage fluid after i.n. or i.t. immunisation, respectively. The immunomodulatory effect of B. firmus on antibody formation was antigen specific.


Assuntos
Adjuvantes Imunológicos , Anticorpos/imunologia , Bacillus/imunologia , Imunidade nas Mucosas , Mucosa Intestinal/imunologia , Mucosa Respiratória/imunologia , Administração Intranasal , Animais , Anticorpos Antibacterianos/sangue , Formação de Anticorpos , Antígenos/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Feminino , Imunidade nas Mucosas/imunologia , Injeções , Intestinos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Traqueia
20.
Clin Exp Immunol ; 119(1): 57-63, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10606964

RESUMO

ICAM-1 (CD54), the ligand for LFA-1 and Mac-1, is up-regulated during inflammatory reaction on the activated vascular endothelium. To determine its role in intestinal inflammation, we induced acute experimental colitis in mice with a deleted ICAM-1 gene, by feeding them with 3% dextran sodium sulphate (DSS) in drinking water for 7 days. Chronic colitis was elicited by DSS similarly, followed by 2 weeks with water. In the acute phase of inflammation, ICAM-1-deficient mice exhibited a significantly lower mortality rate (5%) than control C57Bl/6J mice (35%). Control animals, but not the ICAM-1-deficient mice, exhibited diarrhoea and rectal bleeding. Histological examination of large-bowel samples evaluated the intensity of inflammatory changes, and type and extent of mucosal lesions. In the acute phase, 33.3% of samples from ICAM-1-deficient mice exhibited mucosal defects (flat and fissural ulcers), predominantly mild to moderate inflammatory infiltrate within the lamina propria mucosae and lower grades of mucosal lesions. Much stronger inflammatory changes were present in control animals, flat ulcers (sometimes multiple) and fissural ulcers being observed in 62.5% of samples. Mucosal inflammatory infiltrate was moderate to severe, typically with higher grades of mucosal lesions. In chronic colitis, smaller inflammatory changes were found in the large bowel. The two mouse strains differed, the chronic colitis being accompanied by an increased serum level of anti-epithelial IgA autoantibodies in C57Bl/6 control mice but not in ICAM-1-deficient mice. These findings provide direct evidence of the participation of ICAM-1 molecule in the development of experimentally induced intestinal inflammation.


Assuntos
Colite/prevenção & controle , Molécula 1 de Adesão Intercelular/fisiologia , Animais , Autoanticorpos/sangue , Colite/etiologia , Colite/patologia , Sulfato de Dextrana/administração & dosagem , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Feminino , Imunoglobulina A/sangue , Molécula 1 de Adesão Intercelular/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...