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1.
Cancers (Basel) ; 14(10)2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35626016

RESUMO

This study presents proof of concept assays to validate gold nanoparticles loaded with the bacterial peptide 91-99 of the listeriolysin O toxin (GNP-LLO91-99 nanovaccines) as immunotherapy for bladder tumors. GNP-LLO91-99 nanovaccines showed adjuvant abilities as they induce maturation and activation of monocyte-derived dendritic cells (MoDCs) to functional antigen-presenting cells in healthy donors and patients with melanoma or bladder cancer (BC), promoting a Th1 cytokine pattern. GNP-LLO91-99 nanovaccines were also efficient dendritic cell inducers of immunogenic tumor death using different bladder and melanoma tumor cell lines. The establishment of a pre-clinical mice model of subcutaneous BC confirmed that a single dose of GNP-LLO91-99 nanovaccines reduced tumor burden 4.7-fold and stimulated systemic Th1-type immune responses. Proof of concept assays validated GNP-LLO91-99 nanovaccines as immunotherapy by comparison to anti-CTLA-4 or anti-PD-1 antibodies. In fact, GNP-LLO91-99 nanovaccines increased percentages of CD4+ and CD8+ T cells, B cells, and functional antigen-presenting DCs in tumor-infiltrated lymphocytes, while they reduced the levels of myeloid-derived suppressor cells (MDSC) and suppressor T cells (Treg). We conclude that GNP-LLO91-99 nanovaccines can work as monotherapies or combinatory immunotherapies with anti-CTLA-4 or anti-PD-1 antibodies for solid tumors with high T cell infiltration, such as bladder cancer or melanoma.

2.
An. bras. dermatol ; 96(6): 771-773, Nov.-Dec. 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1355643

RESUMO

Abstract Carcinoma of the mammary crease is a very rare variant of breast carcinoma, in which the skin lesions are usually the presenting sign. The authors present the case of an 88-year-old woman with an exophytic plaque in the mammary crease of approximately ten years duration. The histopathological and immunohistochemical studies confirmed the diagnosis of infiltrative breast carcinoma (carcinoma of the mammary crease variant). This case highlights the important role of the dermatologist in the early diagnosis of this rare variant of breast cancer.


Assuntos
Humanos , Feminino , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Carcinoma , Tórax , Mama
3.
An Bras Dermatol ; 96(6): 771-773, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34600788

RESUMO

Carcinoma of the mammary crease is a very rare variant of breast carcinoma, in which the skin lesions are usually the presenting sign. The authors present the case of an 88-year-old woman with an exophytic plaque in the mammary crease of approximately ten years duration. The histopathological and immunohistochemical studies confirmed the diagnosis of infiltrative breast carcinoma (carcinoma of the mammary crease variant). This case highlights the important role of the dermatologist in the early diagnosis of this rare variant of breast cancer.


Assuntos
Neoplasias da Mama , Carcinoma , Idoso de 80 Anos ou mais , Mama , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Tórax
5.
Front Immunol ; 12: 632304, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33953709

RESUMO

Cross-reactive vaccines recognize common molecular patterns in pathogens and are able to confer broad spectrum protection against different infections. Antigens common to pathogenic bacteria that induce broad immune responses, such as the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of the genera Listeria, Mycobacterium, or Streptococcus, whose sequences present more than 95% homology at the N-terminal GAPDH1-22 peptide, are putative candidates for universal vaccines. Here, we explore vaccine formulations based on dendritic cells (DC) loaded with two molecular forms of Listeria monocytogenes GAPDH (LM-GAPDH), such as mRNA carriers or recombinant proteins, and compare them with the same molecular forms of three other antigens used in experimental vaccines, listeriolysin O of Listeria monocytogeness, Ag85A of Mycobacterium marinum, and pneumolysin of Streptococcus pneumoniae. DC loaded with LM-GAPDH recombinant proteins proved to be the safest and most immunogenic vaccine vectors, followed by mRNA encoding LM-GAPDH conjugated to lipid carriers. In addition, macrophages lacked sufficient safety as vaccines for all LM-GAPDH molecular forms. The ability of DC loaded with LM-GAPDH recombinant proteins to induce non-specific DC activation explains their adjuvant potency and their capacity to trigger strong CD4+ and CD8+ T cell responses explains their high immunogenicity. Moreover, their capacity to confer protection in vaccinated mice against challenges with L. monocytogenes, M. marinum, or S. pneumoniae validated their efficiency as cross-reactive vaccines. Cross-protection appears to involve the induction of high percentages of GAPDH1-22 specific CD4+ and CD8+ T cells stained for intracellular IFN-γ, and significant levels of peptide-specific antibodies in vaccinated mice. We concluded that DC vaccines loaded with L. monocytogenes GAPDH recombinant proteins are cross-reactive vaccines that seem to be valuable tools in adult vaccination against Listeria, Mycobacterium, and Streptococcus taxonomic groups.


Assuntos
Vacinas Bacterianas/imunologia , Gliceraldeído-3-Fosfato Desidrogenases/imunologia , Lipídeos/imunologia , Listeria/imunologia , Mycobacterium/imunologia , RNA Mensageiro/imunologia , Streptococcus/imunologia , Adjuvantes Imunológicos , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Infecções Bacterianas/prevenção & controle , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proteção Cruzada , Reações Cruzadas , Células Dendríticas/imunologia , Gliceraldeído-3-Fosfato Desidrogenases/genética , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Interferon gama/imunologia , Lipídeos/química , Listeria/enzimologia , Listeria/genética , Camundongos , RNA Mensageiro/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia
6.
Vaccines (Basel) ; 9(3)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33802959

RESUMO

Universal vaccines can be prepared with antigens common to different pathogens. In this regard, the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a common virulence factor among pathogenic bacteria of the genera Listeria, Mycobacterium and Streptococcus. Their N-terminal 22 amino acid peptides, GAPDH-L1 (Listeria), GAPDH-M1 (Mycobacterium) and GAPDH-S1 (Streptococcus), share 95-98.55% sequence homology, biochemical and MHC binding abilities and, therefore, are good candidates for universal vaccine designs. Here, we used dendritic cells (DC) as vaccine platforms to test GAPDH epitopes that conferred protection against Listeria monocytogenes, Mycobacterium marinum or Streptococcus pneumoniae in our search of epitopes for universal vaccines. DC loaded with GAPDH-L1, GAPDH-M1 or GAPDH-S1 peptides show high immunogenicity measured by the cellular DTH responses in mice, lacked toxicity and were capable of cross-protection immunity against mice infections with each one of the pathogens. Vaccine efficiency correlated with high titers of anti-GAPDH-L1 antibodies in sera of vaccinated mice, a Th1 cytokine pattern and high frequencies of GAPDH-L1-specific CD4+ and CD8+ T cells and IFN-γ producers in the spleens. We concluded that GAPDH-L1 peptide was the best epitope for universal vaccines in the Listeria, Mycobacterium or Streptococcus taxonomic groups, whose pathogenic strains caused relevant morbidities in adults and especially in the elderly.

8.
Front Cell Infect Microbiol ; 10: 573348, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33194812

RESUMO

The glycolytic enzyme and bacterial virulence factor of Listeria monocytogenes, the glyceraldehyde-3-phosphate dehydrogenase (GAPDH, Lmo2459), ADP-ribosylated the small GTPase, Rab5a, and blocked phagosome maturation. This inhibitory activity localized within the NAD binding domain of GAPDH at the N-terminal 1-22 peptides, also conferred listeriosis protection when used in dendritic cell-based vaccines. In this study, we explore GAPDH of Listeria, Mycobacterium, and Streptococcus spp. taxonomic groups to search for epitopes that confer broad protection against pathogenic strains of these bacteria. GAPDH multivalent epitopes are selected if they induce inhibitory actions and wide-ranging immune responses. Proteomic isolation of GAPDH from dendritic cells infected with Listeria, Mycobacterium, or Streptococcus confirmed similar enzymatic, Rab5a inhibitory and immune stimulation abilities. We identified by bioinformatics and functional analyses GAPDH N-terminal 1-22 peptides from Listeria, Mycobacterium, and Streptococcus that shared 95% sequence homology, enzymatic activity, and B and T cell immune domains. Sera obtained from patients or mice infected with hypervirulent pathogenic Listeria, Mycobacterium, or Streptococcus presented high levels of anti-GAPDH 1-22 antibodies and Th2 cytokines. Monocyte derived dendritic cells from healthy donors loaded with GAPDH 1-22 peptides from Listeria, Mycobacterium, or Streptococcus showed activation patterns that correspond to cross-immunity abilities. In summary, GAPDH 1-22 peptides appeared as putative candidates to include in multivalent dendritic based vaccine platforms for Listeria, Mycobacterium, or Streptococcus.


Assuntos
Listeria , Mycobacterium , Animais , Epitopos , Gliceraldeído-3-Fosfato Desidrogenases/genética , Humanos , Camundongos , Proteômica , Streptococcus , Vacinas Combinadas
9.
Oncoimmunology ; 8(2): e1541534, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30713801

RESUMO

Gold glyconanoparticles loaded with the listeriolysin O peptide 91-99 (GNP-LLO91-99), a bacterial peptide with anti-metastatic properties, are vaccine delivery platforms facilitating immune cell targeting and increasing antigen loading. Here, we present proof of concept analyses for the consideration of GNP-LLO91-99 nanovaccines as a novel immunotherapy for cutaneous melanoma. Studies using mouse models of subcutaneous melanoma indicated that GNP-LLO91-99 nanovaccines recruite and modulate dendritic cell (DC) function within the tumour, alter tumour immunotolerance inducing melanoma-specific cytotoxic T cells, cause complete remission and improve survival. GNP-LLO91-99 nanovaccines showed superior tumour regression and survival benefits, when combined with anti-PD-1 or anti-CTLA-4 checkpoint inhibitors, resulting in an improvement in the efficacy of these immunotherapies. Studies on monocyte-derived DCs from patients with stage IA, IB or IIIB melanoma confirmed the ability of GNP-LLO91-99 nanovaccines to complement the action of checkpoint inhibitors, by not only reducing the expression of cell-death markers on DCs, but also potentiating DC antigen-presentation. We propose that GNP-LLO91-99 nanovaccines function as immune stimulators and immune effectors and serve as safe cancer therapies, alone or in combination with other immunotherapies.

10.
Oncotarget ; 8(33): 53916-53934, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28903312

RESUMO

Clinical cases of neonatal listeriosis are associated with brain disease and fetal loss due to complications in early or late pregnancy, which suggests that microglial function is altered. This is believed to be the first study to link microglial apoptosis with neonatal listeriosis and listeriosis-associated brain disease, and to propose a new nanovaccine formulation that reverses all effects of listeriosis and confers Listeria monocytogenes (LM)-specific immunity. We examined clinical cases of neonatal listeriosis in 2013-2015 and defined two useful prognostic immune biomarkers to design listeriosis vaccines: high anti-GAPDH1-22 titres and tumor necrosis factor (TNF)/interleukin (IL)-6 ratios. Therefore, we developed a nanovaccine with gold glyco-nanoparticles conjugated to LM peptide 1-22 of GAPDH (Lmo2459), GNP-GAPDH1-22 nanovaccinesformulated with a pro-inflammatory Toll-like receptor 2/4-targeted adjuvant. Neonates born to non-vaccinated pregnant mice with listeriosis, showed brain and vascular diseases and significant microglial dysfunction by induction of TNF-α-mediated apoptosis. This programmed TNF-mediated suicide explains LM dissemination in brains and livers and blocks production of early pro-inflammatory cytokines such as IL-1ß and interferon-α/ß. In contrast, neonates born to GNP-GAPDH1-22-vaccinated mothers before LM infection, did not develop listeriosis or brain diseases and had functional microglia. In nanovaccinated mothers, immune responses shifted towards Th1/IL-12 pro-inflammatory cytokine profiles and high production of anti-GAPDH1-22 antibodies, suggesting good induction of LM-specific memory.

11.
Oncotarget ; 7(13): 16855-65, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-26942874

RESUMO

Vaccination with dendritic cells (DCs) is proposed to induce lasting responses against melanoma but its survival benefit in patients needs to be demonstrated. We propose a DC-targeted vaccine loaded with a Listeria peptide with exceptional anti-tumour activity to prevent metastasis of melanoma. Mice vaccinated with vaccines based on DCs loaded with listeriolysin O peptide (91-99) (LLO91-99) showed clear reduction of metastatic B16OVA melanoma size and adhesion, prevention of lung metastasis, enhanced survival, and reversion of immune tolerance. Robust innate and specific immune responses explained the efficiency of DC-LLO91-99 vaccines against B16OVA melanoma. The noTable features of this vaccine related to melanoma reduction were: expansion of immune-dominant LLO91-99-specific CD8 T cells that helped to expand melanoma-specific CD8+ T cells; high numbers of tumour-infiltrating lymphocytes with a cytotoxic phenotype; and a decrease in CD4+CD25high regulatory T cells. This vaccine might be a useful alternative treatment for advanced melanoma, alone or in combination with other therapies.


Assuntos
Toxinas Bacterianas/farmacologia , Vacinas Anticâncer/farmacologia , Células Dendríticas/imunologia , Proteínas de Choque Térmico/farmacologia , Proteínas Hemolisinas/farmacologia , Melanoma Experimental/patologia , Neoplasias Cutâneas/patologia , Animais , Toxinas Bacterianas/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Proteínas de Choque Térmico/imunologia , Proteínas Hemolisinas/imunologia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Melanoma Experimental/imunologia , Camundongos , Neoplasias Cutâneas/imunologia
12.
Nanomaterials (Basel) ; 6(8)2016 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-28335280

RESUMO

Listeriosis is a fatal infection for fetuses and newborns with two clinical main morbidities in the neonatal period, meningitis and diffused cutaneous lesions. In this study, we vaccinated pregnant females with two gold glyconanoparticles (GNP) loaded with two peptides, listeriolysin peptide 91-99 (LLO91-99) or glyceraldehyde-3-phosphate dehydrogenase 1-22 peptide (GAPDH1-22). Neonates born to vaccinated mothers were free of bacteria and healthy, while non-vaccinated mice presented clear brain affections and cutaneous diminishment of melanocytes. Therefore, these nanoparticle vaccines are effective measures to offer pregnant mothers at high risk of listeriosis interesting therapies that cross the placenta.

13.
PLoS One ; 10(3): e0117923, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25760947

RESUMO

Listeria monocytogenes is a gram-positive bacteria and human pathogen widely used in cancer immunotherapy because of its capacity to induce a specific cytotoxic T cell response in tumours. This bacterial pathogen strongly induces innate and specific immunity with the potential to overcome tumour induced tolerance and weak immunogenicity. Here, we propose a Listeria based vaccination for melanoma based in its tropism for these tumour cells and its ability to transform in vitro and in vivo melanoma cells into matured and activated dendritic cells with competent microbicidal and antigen processing abilities. This Listeria based vaccination using low doses of the pathogen caused melanoma regression by apoptosis as well as bacterial clearance. Vaccination efficacy is LLO dependent and implies the reduction of LLO-specific CD4+ T cell responses, strong stimulation of innate pro-inflammatory immune cells and a prevalence of LLO-specific CD8+ T cells involved in tumour regression and Listeria elimination. These results support the use of low doses of pathogenic Listeria as safe melanoma therapeutic vaccines that do not require antibiotics for bacterial removal.


Assuntos
Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Listeria monocytogenes/imunologia , Melanoma/terapia , Neoplasias Cutâneas/terapia , Animais , Apoptose , Células CHO , Linhagem Celular Tumoral , Cricetulus , Células Dendríticas/microbiologia , Humanos , Listeria monocytogenes/fisiologia , Melanoma/imunologia , Melanoma/microbiologia , Camundongos , Transplante de Neoplasias , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/microbiologia , Linfócitos T Citotóxicos/imunologia , Tropismo Viral
14.
Artigo em Inglês | MEDLINE | ID: mdl-24600592

RESUMO

The use of live Listeria-based vaccines carries serious difficulties when administrated to immunocompromised individuals. However, cellular carriers have the advantage of inducing multivalent innate immunity as well as cell-mediated immune responses, constituting novel and secure vaccine strategies in listeriosis. Here, we compare the protective efficacy of dendritic cells (DCs) and macrophages and their safety. We examined the immune response of these vaccine vectors using two Listeria antigens, listeriolysin O (LLO) and glyceraldehyde-3-phosphate-dehydrogenase (GAPDH), and several epitopes such as the LLO peptides, LLO189-201 and LLO91-99 and the GAPDH peptide, GAPDH1-22. We discarded macrophages as safe vaccine vectors because they show anti-Listeria protection but also high cytotoxicity. DCs loaded with GAPDH1-22 peptide conferred higher protection and security against listeriosis than the widely explored LLO91-99 peptide. Anti-Listeria protection was related to the changes in DC maturation caused by these epitopes, with high production of interleukin-12 as well as significant levels of other Th1 cytokines such as monocyte chemotactic protein-1, tumor necrosis factor-α, and interferon-γ, and with the induction of GAPDH1-22-specific CD4(+) and CD8(+) immune responses. This is believed to be the first study to explore the use of a novel GAPDH antigen as a potential DC-based vaccine candidate for listeriosis, whose efficiency appears to highlight the relevance of vaccine designs containing multiple CD4(+) and CD8(+) epitopes.


Assuntos
Antígenos de Bactérias/imunologia , Vacinas Bacterianas/efeitos adversos , Vacinas Bacterianas/imunologia , Células Dendríticas/imunologia , Gliceraldeído-3-Fosfato Desidrogenases/imunologia , Listeria/imunologia , Listeriose/prevenção & controle , Animais , Toxinas Bacterianas/imunologia , Vacinas Bacterianas/administração & dosagem , Citocinas/metabolismo , Proteínas de Choque Térmico/imunologia , Proteínas Hemolisinas/imunologia , Listeria/enzimologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL
15.
Glia ; 62(2): 233-46, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24311463

RESUMO

Microglia, the innate immune cells of the brain, plays a central role in cerebral listeriosis. Here, we present evidence that microglia control Listeria infection differently than macrophages. Infection of primary microglial cultures and murine cell lines with Listeria resulted in a dual function of the two gene expression programmes involved in early and late immune responses in macrophages. Whereas the bacterial gene hly seems responsible for both transcriptional programmes in macrophages, Listeria induces in microglia only the tumor necrosis factor (TNF)-regulated transcriptional programme. Listeria also represses in microglia the late immune response gathered in two clusters, microbial degradation, and interferon (IFN)-inducible genes. The bacterial gene actA was required in microglia to induce TNF-regulated responses and to repress the late response. Isolation of microglial phagosomes revealed a phagosomal environment unable to destroy Listeria. Microglial phagosomes were also defective in several signaling and trafficking components reported as relevant for Listeria innate immune responses. This transcriptional strategy in microglia induced high levels of TNF-α and monocyte chemotactic protein-1 and low production of other neurotoxic compounds such as nitric oxide, hydrogen peroxide, and Type I IFNs. These cytokines and toxic microglial products are also released by primary microglia, and this cytokine and chemokine cocktail display a low potential to trigger neuronal apoptosis. This overall bacterial strategy strongly suggests that microglia limit Listeria inflammation pattern exclusively through TNF-mediated responses to preserve brain integrity.


Assuntos
Imunidade Inata/imunologia , Listeria monocytogenes/metabolismo , Listeriose/metabolismo , Macrófagos/metabolismo , Microglia/metabolismo , Animais , Apoptose , Células Cultivadas , Citocinas/metabolismo , Listeria monocytogenes/genética , Listeria monocytogenes/imunologia , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Microglia/imunologia , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
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