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1.
PLoS One ; 14(9): e0222148, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31513620

RESUMO

Influenza and its bacterial complications are a leading cause of morbidity and mortality worldwide. The effect of combined immunization with live influenza vaccine and recombinant chimeric pneumococcal protein in dual infection caused by influenza H1N1 and S. pneumoniae (serotype 3) has been studied. The combined vaccine consisted of the strain A/California/2009/38 (H1N1) pdm and chimeric recombinant protein PSPF composed of immunodominant fragments of the surface virulence factors of S. pneumoniae-PsaA, PspA, and Shr1875-associated with modified salmonella flagellin. Vaccinated mice were infected with the influenza virus 24 hours before or 24 hours after the onset of pneumococcal infection. The protective effect of combined vaccination was shown on both models of viral-bacterial infection.


Assuntos
Coinfecção/prevenção & controle , Vacinas contra Influenza/administração & dosagem , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Animais , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Modelos Animais de Doenças , Feminino , Flagelina/imunologia , Flagelina/metabolismo , Vacinas contra Influenza/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Vacinas Pneumocócicas/imunologia , Proteínas Recombinantes/imunologia , Resultado do Tratamento , Vacinação , Vacinas Atenuadas , Vacinas Combinadas , Fatores de Virulência/imunologia , Fatores de Virulência/metabolismo
2.
Benef Microbes ; 9(6): 937-949, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30099893

RESUMO

The biological effects of three probiotic strains Lactobacillus rhamnosus K32, Bifidobacterium longum GT15, Enterococcus faecium L3 and their mixture were studied using a model of dysbiosis induced in rats by antibiotics. It was found that after taking different probiotics intestinal microbiota changed in a strain-specific manner. The maximal activity against pathogens was revealed after the administration of a mixture of bacterial strains under study or a single strain of enterococci. The strain E. faecium L3 showed the most activity against both Klebsiella spp. and Bacteroides fragilis. It helped to restore the original content of Faecalibacterium prausnitzii. The number of Klebsiella spp. was the same in the group receiving L. rhamnosus K32 and the group of animals, which was not consuming probiotics. Different probiotic strains included in the composition had various immunological effects. Probiotic bifidobacteria, enterococci and the mixture of three probiotics stimulated of mRNA expression of interleukin (IL)-10 in mesenteric lymph nodes. The changes in microbiota after consuming an enterococcal probiotic correlated with an increase in transforming growth factor (TGF)-ß and IL-10 content in blood serum and an increase of the intestinal mucus layer. Consumption of L. rhamnosus K32 led to the stimulation of IL-8 expression in mesenteric lymph nodes. Control group not receiving probiotics was characterised by expression of pro-inflammatory cytokines, damage of epithelial cells and the destruction of their tight junctions. The damage to the ultrastructure of the mucosa was prevented in all the groups taking probiotics.


Assuntos
Bifidobacterium longum/imunologia , Disbiose/terapia , Enterococcus faecium/imunologia , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/imunologia , Lacticaseibacillus rhamnosus/imunologia , Probióticos/administração & dosagem , Animais , Bifidobacterium longum/crescimento & desenvolvimento , Terapia Biológica/métodos , Modelos Animais de Doenças , Disbiose/induzido quimicamente , Enterococcus faecium/crescimento & desenvolvimento , Imunidade Inata , Fatores Imunológicos/sangue , Lacticaseibacillus rhamnosus/crescimento & desenvolvimento , Ratos , Resultado do Tratamento
3.
PLoS One ; 13(5): e0196564, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29727446

RESUMO

Streptococcus agalactiae, or group B streptococcus (GBS), is an important pathogen as it is the leading cause of neonatal deaths due to sepsis, meningitis or bacterial pneumonia. Although the development of an effective and safe GBS vaccine is on the agenda of many research labs, there is no GBS vaccine on the market yet. In the present study we attempted to engineer a live vaccine strain based on Bac, a surface protein of GBS, incorporated into a surface fimbrial protein of probiotic Enterococcus. The resulting strain induced specific systemic and local immune responses in mice and provided protection against GBS when administered via the intranasal, oral or intravaginal immunization routes.


Assuntos
Imunidade nas Mucosas , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/prevenção & controle , Vacinas Estreptocócicas/imunologia , Streptococcus agalactiae/imunologia , Streptococcus agalactiae/patogenicidade , Administração Intranasal , Administração Intravaginal , Administração Oral , Animais , Anticorpos Antibacterianos/biossíntese , Anticorpos Antibacterianos/sangue , Carga Bacteriana , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Enterococcus faecium/genética , Enterococcus faecium/imunologia , Feminino , Proteínas de Fímbrias/genética , Proteínas de Fímbrias/imunologia , Camundongos , Probióticos , Infecções Estreptocócicas/microbiologia , Vacinas Estreptocócicas/administração & dosagem , Vacinas Estreptocócicas/genética , Streptococcus agalactiae/genética , Vacinas Conjugadas/administração & dosagem , Vacinas Conjugadas/genética , Vacinas Conjugadas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
4.
Bull Exp Biol Med ; 164(3): 347-350, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29308558

RESUMO

Immunomodulatory properties of S. pyogenes protein M111 were studied on the model of Gurov strain and its isogenic mutant not expressing M protein. Mouse resident peritoneal macrophages were incubated with bacteria and generation of nitroxide and superoxide anions and production of IL-6, IL-10, and IL-17 were evaluated. Protein M111 modified macrophage response: it exhibited antiphagocytic activity, prevented ROS formation, and stimulated the production of anti-inflammatory cytokine IL-10. The results suggested that this protein could serve in the bacteria as a factor suppressing the host defense forces and promoting the realization of the strategy beneficial for pathogens - escape from the host immune defense.


Assuntos
Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Transporte/genética , Deleção de Genes , Evasão da Resposta Imune , Macrófagos Peritoneais/microbiologia , Streptococcus pyogenes/genética , Animais , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas de Transporte/imunologia , Expressão Gênica , Interleucina-10/biossíntese , Interleucina-10/imunologia , Interleucina-17/biossíntese , Interleucina-17/imunologia , Interleucina-6/biossíntese , Interleucina-6/imunologia , Macrófagos Peritoneais/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Óxidos de Nitrogênio/imunologia , Óxidos de Nitrogênio/metabolismo , Fagocitose , Cultura Primária de Células , Streptococcus pyogenes/imunologia , Streptococcus pyogenes/patogenicidade , Superóxidos/imunologia , Superóxidos/metabolismo
6.
Acta Virol ; 34(4): 376-9, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1705746

RESUMO

Coxiella burnetii antigens stimulate the defence against growth of hepatoma 22a cells. The antigen-stimulated mice survived longer, they considerably later developed palpable tumours and showed a retarded tumour growth. The enhanced resistance to tumour growth may be explained by at least 2 interrelated phenomena; namely by the induction of interferon-like activity and an increased NK cell activity.


Assuntos
Adjuvantes Imunológicos , Antígenos de Bactérias/administração & dosagem , Coxiella/imunologia , Neoplasias Hepáticas Experimentais/terapia , Animais , Imunoterapia , Interferons/biossíntese , Células Matadoras Naturais/imunologia , Neoplasias Hepáticas Experimentais/imunologia , Camundongos , Camundongos Endogâmicos C3H
7.
Acta Virol ; 31(5): 424-33, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2446485

RESUMO

The effect of immobilization stress on the course of various forms of influenza infection has been investigated. Influenza was produced in 10-14-week-old inbred mice by intranasal infection with pathogenic influenza virus strain A/PR/8/34 (H1N1) at different doses. Immobilization for 6 hr resulted in the appearance of virus-inhibiting activity in the serum of mice. This activity suppressed the reproduction of test-virus in tissue culture, it was resistant to acid pH 2.0 treatment and to heating at 56 degrees C. However, the high level of virus-inhibiting activity failed to protect the animals from subsequent development of lethal influenza infection. Immobilization stress caused a transient depression of virus induced interferon (IFN) production, as revealed by the use of virus inducer at early intervals after stress. Contemporarily, the stress could aggravate the course of virus infection promoting its transition from non-lethal form into a lethal one and virus penetration into brain.


Assuntos
Infecções por Orthomyxoviridae/etiologia , Estresse Fisiológico/complicações , Animais , Suscetibilidade a Doenças , Imobilização , Vírus da Influenza A , Interferons/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos C57BL/sangue , Camundongos Endogâmicos CBA/sangue , Estresse Fisiológico/sangue , Fatores de Tempo
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