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1.
PLoS One ; 15(1): e0228055, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31945121

RESUMO

Pneumococcal Surface Protein A (PspA) has been successfully tested as vaccine candidate against Streptococcus pneumoniae infections. Vaccines able to induce PspA-specific antibodies and Th1 cytokines usually provide protection in mice. We have shown that the whole cell pertussis vaccine (wP) or components from acellular pertussis vaccines, such as Pertussis Toxin or Filamentous Hemagglutinin (FHA), are good adjuvants to PspA, suggesting that combined pertussis-PspA vaccines would be interesting strategies against the two infections. Here, we evaluated the potential of wP as a delivery vector to PspA. Bordetella pertussis strains producing a PspA from clade 4 (PspA4Pro) fused to the N-terminal region of FHA (Fha44) were constructed and inactivated with formaldehyde for the production of wPPspA4Pro. Subcutaneous immunization of mice with wPPspA4Pro induced low levels of anti-PspA4 IgG, even after 3 doses, and did not protect against a lethal pneumococcal challenge. Prime-boost strategies using wPPspA4Pro and PspA4Pro showed that there was no advantage in using the wPPspA4Pro vaccine. Immunization of mice with purified PspA4Pro induced higher levels of antibodies and protection against pneumococcal infection than the prime-boost strategies. Finally, purified Fha44:PspA4Pro induced high levels of anti-PspA4Pro IgG, but no protection, suggesting that the antibodies induced by the fusion protein were not directed to protective epitopes.


Assuntos
Adesinas Bacterianas/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Proteínas de Bactérias/farmacologia , Vacina contra Coqueluche/administração & dosagem , Infecções Pneumocócicas/prevenção & controle , Fatores de Virulência de Bordetella/administração & dosagem , Animais , Antígenos de Bactérias/farmacologia , Antígenos de Superfície/farmacologia , Portadores de Fármacos/administração & dosagem , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Vacinação
2.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;45(8): 737-745, Aug. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-643650

RESUMO

Reports remain insufficient on whether and how prostate-specific membrane antigen (PSMA) can influence in vivo osseous metastasis of prostate cancer (PCa). In the present study, the authors induced stable expression of PSMA in mouse PCa cell line RM-1. In vivo osseous metastasis was induced in 37 6-week-old female C57BL/6 mice weighing 22.45 ± 0.456 g. RM-1 cells were actively injected into the femoral bone cavity, leading to bilateral dissymmetry of bone density in the femoral bone. Tumor cells were also detected in bone tissue by pathological examination. The impact on bone density was demonstrated by the significant difference between animals injected with RM-PSMA cells (0.0738 ± 0.0185 g/cm²) and animals injected with RM-empty plasmid cells (0.0895 ± 0.0241 g/cm²). The lytic bone lesion of the RM-PSMA group (68.4%) was higher than that of the control group (27.8%). Immunohistochemistry showed that the expression of both vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) was distinctly higher in the RM-PSMA group than in the control group, while ELISA and Western blot assay indicated that VEGF and MMP-9 were higher in the RM-PSMA group compared to the control group (in vitro). Thus, the present study proposed and then confirmed for the first time that PSMA can promote in vivo osseous metastasis of PCa by increasing sclerotic destruction of PCa cells. Further analyses also suggested that PSMA functions positively on the invasive ability of RM-1 by increasing the expression of MMP-9 and VEGF by osseous metastases in vivo.


Assuntos
Animais , Feminino , Masculino , Camundongos , Antígenos de Superfície/metabolismo , Neoplasias Ósseas/secundário , Glutamato Carboxipeptidase II/metabolismo , Neoplasias da Próstata/patologia , Antígenos de Superfície/farmacologia , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Glutamato Carboxipeptidase II/farmacologia , Imuno-Histoquímica , Metaloproteinase 9 da Matriz/metabolismo , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias da Próstata/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
3.
Braz J Med Biol Res ; 45(8): 737-45, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22584637

RESUMO

Reports remain insufficient on whether and how prostate-specific membrane antigen (PSMA) can influence in vivo osseous metastasis of prostate cancer (PCa). In the present study, the authors induced stable expression of PSMA in mouse PCa cell line RM-1. In vivo osseous metastasis was induced in 37 6-week-old female C57BL/6 mice weighing 22.45 ± 0.456 g. RM-1 cells were actively injected into the femoral bone cavity, leading to bilateral dissymmetry of bone density in the femoral bone. Tumor cells were also detected in bone tissue by pathological examination. The impact on bone density was demonstrated by the significant difference between animals injected with RM-PSMA cells (0.0738 ± 0.0185 g/cm²) and animals injected with RM-empty plasmid cells (0.0895 ± 0.0241 g/cm²). The lytic bone lesion of the RM-PSMA group (68.4%) was higher than that of the control group (27.8%). Immunohistochemistry showed that the expression of both vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) was distinctly higher in the RM-PSMA group than in the control group, while ELISA and Western blot assay indicated that VEGF and MMP-9 were higher in the RM-PSMA group compared to the control group (in vitro). Thus, the present study proposed and then confirmed for the first time that PSMA can promote in vivo osseous metastasis of PCa by increasing sclerotic destruction of PCa cells. Further analyses also suggested that PSMA functions positively on the invasive ability of RM-1 by increasing the expression of MMP-9 and VEGF by osseous metastases in vivo.


Assuntos
Antígenos de Superfície/metabolismo , Neoplasias Ósseas/secundário , Glutamato Carboxipeptidase II/metabolismo , Neoplasias da Próstata/patologia , Animais , Antígenos de Superfície/farmacologia , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Feminino , Glutamato Carboxipeptidase II/farmacologia , Imuno-Histoquímica , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias da Próstata/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
4.
Melanoma Res ; 18(3): 172-83, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18477891

RESUMO

Trypanosoma cruzi infection is known to confer resistance to tumor development in mice, and in-vitro studies have shown the toxic effects of parasite extracts on cancer cell cultures. Investigations in which T. cruzi molecules exhibit antitumor activity have just begun. Here, we used a tumorigenic cell line Tm5, derived from mouse melanocytes melan-a, to test the effect of J18, a recombinant protein based on T. cruzi surface molecule gp82 fused to glutathione-S-transferase (GST). J18 induced actin cytoskeleton disruption in Tm5 but not in melan-a cells. Several changes indicative of apoptosis were detected in Tm5 melanoma cells but not in melan-a cells treated with J18, such as the flipping of phosphatidylserine from the inner to the external side of the plasma membrane, altered nuclear morphology, DNA fragmentation, increase in mitochondria depolarization, and in caspase-3 activity. Retention of NF-kappaB in the cytoplasm was another alteration observed specifically in J18-treated Tm5 cells. No such alterations were found in Tm5 cells treated with GST. In-vivo experiments showed that C57BL/6 mice inoculated with Tm5 cells, treated at the site of tumor cell inoculation with J18, developed tumors of smaller size than mice treated with phosphate-buffered saline or GST and survived longer.


Assuntos
Apoptose/efeitos dos fármacos , Melanoma/patologia , Proteínas de Protozoários/farmacologia , Trypanosoma cruzi , Glicoproteínas Variantes de Superfície de Trypanosoma/farmacologia , Animais , Antígenos de Superfície/farmacologia , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Proteínas Recombinantes/farmacologia , Células Tumorais Cultivadas
5.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;28(6): 651-4, Jun. 1995. tab
Artigo em Inglês | LILACS | ID: lil-154933

RESUMO

Semipurified K99 and F41 fimbrial antigens were used to prepare an oil-emulsified vaccine against bovine enterotoxigenic colibacillosis. Nine Nelore cows about 7 months pregnant were divided into 3 groups (A, B and C) of 3 animals each, which received different doses of vaccine (1,500 HU, 750 HU and 380 HU, respectively) 8 and 2 weeks before delivery, in the neck by the subcutaneous route. As a control (group D), 3 pregnant cows of the same breed were not vaccinated for later challange of their calves. Vaccine efficiency was measured by the serological tests double diffusion and ELISA. Challenge of calves from the vaccinated and from the three control unvaccinated cows was carried out with the virulent Escherichia coli B41 strain (0101), STa+, K99+, F41+). Two of the 3 calves from unvaccinated cows died within 48 h with acute diarrhea. E. coli B4 was recovered as pure culture from their stools. In contrast, none of the calves born from vaccinated cows presented diarrhea. These data suggest that the antibody transfer to calves through colostrum gave full protection aginst the challenge. This semipurified fimbrial vaccine against K99-F41-harboring strains is the first oil-emulsified immunogen prepared in Brazil, which was not only efficient, but also had no adverse effects on vaccinated pregnant cows


Assuntos
Bovinos , Animais , Feminino , Gravidez , Antígenos de Superfície/farmacologia , Vacinas Bacterianas/imunologia , Fímbrias Bacterianas/imunologia , Infecções por Escherichia coli/imunologia , Doenças dos Bovinos/prevenção & controle , Ensaio de Imunoadsorção Enzimática
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