Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Front Immunol ; 14: 1156714, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37180141

RESUMO

Introduction: Virus vectored genetic vaccines (Vvgv) represent a promising approach for eliciting immune protection against infectious diseases and cancer. However, at variance with classical vaccines to date, no adjuvant has been combined with clinically approved genetic vaccines, possibly due to the detrimental effect of the adjuvant-induced innate response on the expression driven by the genetic vaccine vector. We reasoned that a potential novel approach to develop adjuvants for genetic vaccines would be to "synchronize" in time and space the activity of the adjuvant with that of the vaccine. Methods: To this aim, we generated an Adenovirus vector encoding a murine anti-CTLA-4 monoclonal antibody (Ad-9D9) as a genetic adjuvant for Adenovirus based vaccines. Results: The co-delivery of Ad-9D9 with an Adeno-based COVID-19 vaccine encoding the Spike protein resulted in stronger cellular and humoral immune responses. In contrast, only a modest adjuvant effect was achieved when combining the vaccine with the same anti-CTLA-4 in its proteinaceous form. Importantly, the administration of the adjuvant vector at different sites of the vaccine vector abrogates the immunostimulatory effect. We showed that the adjuvant activity of Ad-α-CTLA-4 is independent from the vaccine antigen as it improved the immune response and efficacy of an Adenovirus based polyepitope vaccine encoding tumor neoantigens. Discussion: Our study demonstrated that the combination of Adenovirus Encoded Adjuvant (AdEnA) with an Adeno-encoded antigen vaccine enhances immune responses to viral and tumor antigens, representing a potent approach to develop more effective genetic vaccines.


Assuntos
Infecções por Adenoviridae , Vacinas contra Adenovirus , COVID-19 , Doenças Transmissíveis , Neoplasias , Camundongos , Animais , Humanos , Adenoviridae/genética , Vacinas contra COVID-19 , Adjuvantes Imunológicos , Adjuvantes Farmacêuticos
2.
Sci Total Environ ; 835: 155388, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35489490

RESUMO

Wastewater treatment plants (WWTPs) collect wastewater from various sources and use different treatment processes to reduce the load of pollutants in the environment. Since the removal of many chemical pollutants and bacteria by WWTPs is incomplete, they constitute a potential source of contaminants. The continuous release of contaminants through WWTP effluents can compromise the health of the aquatic ecosystems, even if they occur at very low concentrations. The main objective of this work was to characterize, over a period of four months, the treatment steps starting from income to the effluent and 5 km downstream to the receiving river. In this context, the efficiency removal of chemical pollutants (e.g. hormones and pharmaceuticals, including antibiotics) and bacteria was assessed in a WWTP case study by using a holistic approach. It embraces different chemical and biological-based methods, such as pharmaceutical analysis by HPLC-MSMS, growth rate inhibition in algae, ligand binding estrogen receptor assay, microbial community study by 16S and shotgun sequencing along with relative quantification of resistance genes by quantitative polymerase chain reaction. Although both, chemical and biological-based methods showed a significant reduction of the pollutant burden in effluent and surface waters compared to the influent of the WWTP, no complete removal of pollutants, pathogens and antibiotic resistance genes was observed.


Assuntos
Microbiota , Poluentes Químicos da Água , Purificação da Água , Bactérias , Monitoramento Ambiental/métodos , Rios/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise
3.
J Immunother Cancer ; 9(11)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34824160

RESUMO

BACKGROUND: A number of different immune pathways are involved in the effective killing of cancer cells, collectively named as the 'Cancer Immunity Cycle'. Anti-PD-1 checkpoint blockade (CPB) therapy is active on one of these pathways and reinvigorates anticancer T cell immunity, leading to long-term responses in a limited fraction of patients with cancer. We have previously shown that neoantigens-based adenovirus vectored vaccine in combination with anti-PD-1 further expands pre-existing anticancer immunity and elicits novel neoantigen-specific T cells thereby increasing efficacy to 50% of tumor clearance in mice. Here we added a third component to the CPB plus vaccine combination, which is able to modify the suppressive tumor microenvironment by reducing the number of tumor-infiltrating regulatory T cells (Tregs), as strategy for improving the therapeutic efficacy and overcoming resistance. METHODS: The antitumor efficacy of anti-PD-1, neoantigen vaccine and Treg modulating agents, either Bempegaldesleukin (BEMPEG: NKTR-214) or an anti-CTLA-4 mAb with Treg-depleting activity, was investigated in murine tumor models. We evaluated tumor growth in treated animals, neoantigen-specific T cells in tumors, tumor-infiltrating lymphocytes (TILs) and intratumoral Tregs. RESULTS: The addition of BEMPEG or anti-CTLA-4 to the combination of vaccine and anti-PD-1 led to complete eradication of large tumors in nearby 100% of treated animals, in association with expansion and activation of cancer neoantigen-specific T cells and reduction of tumor-infiltrating Tregs. CONCLUSION: These data support the notion that the integrated regulation of three steps of the cancer immunity cycle, including expansion of neoantigen-specific T cells, reversal of the exhausted T cell phenotype together with the reduction of intratumoral Tregs may represent a novel rationally designed drug combination approach to achieve higher cure rates.


Assuntos
Vacinas Anticâncer/imunologia , Expressão Gênica/genética , Imunoterapia/métodos , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T Reguladores/imunologia , Animais , Feminino , Humanos , Camundongos
4.
Vaccines (Basel) ; 9(8)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34452005

RESUMO

Neoantigens are tumor-specific antigens able to induce T-cell responses, generated by mutations in protein-coding regions of expressed genes. Previous studies demonstrated that only a limited subset of mutations generates neoantigens in microsatellite stable tumors. We developed a method, called VENUS (Vaccine-Encoded Neoantigens Unrestricted Selection), to prioritize mutated peptides with high potential to be neoantigens. Our method assigns to each mutation a weighted score that combines the mutation allelic frequency, the abundance of the transcript coding for the mutation, and the likelihood to bind the patient's class-I major histocompatibility complex alleles. By ranking mutated peptides encoded by mutations detected in nine cancer patients, VENUS was able to select in the top 60 ranked peptides, the 95% of neoantigens experimentally validated including both CD8 and CD4 T cell specificities. VENUS was evaluated in a murine model in the context of vaccination with an adeno vector encoding the top ranked mutations prioritized in the MC38 cell line. Efficacy studies demonstrated anti tumoral activity of the vaccine when used in combination with checkpoint inhibitors. The results obtained highlight the importance of a combined scoring system taking into account multiple features of each tumor mutation to improve the accuracy of neoantigen prediction.

6.
Mol Ther ; 29(8): 2412-2423, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-33895322

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by the emergent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) threatens global public health, and there is an urgent need to develop safe and effective vaccines. Here, we report the generation and the preclinical evaluation of a novel replication-defective gorilla adenovirus-vectored vaccine encoding the pre-fusion stabilized Spike (S) protein of SARS-CoV-2. We show that our vaccine candidate, GRAd-COV2, is highly immunogenic both in mice and macaques, eliciting both functional antibodies that neutralize SARS-CoV-2 infection and block Spike protein binding to the ACE2 receptor, and a robust, T helper (Th)1-dominated cellular response. We show here that the pre-fusion stabilized Spike antigen is superior to the wild type in inducing ACE2-interfering, SARS-CoV-2-neutralizing antibodies. To face the unprecedented need for vaccine manufacturing at a massive scale, different GRAd genome deletions were compared to select the vector backbone showing the highest productivity in stirred tank bioreactors. This preliminary dataset identified GRAd-COV2 as a potential COVID-19 vaccine candidate, supporting the translation of the GRAd-COV2 vaccine in a currently ongoing phase I clinical trial (ClinicalTrials.gov: NCT04528641).


Assuntos
Adenoviridae/imunologia , Vacinas contra Adenovirus/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Gorilla gorilla/imunologia , Imunogenicidade da Vacina/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Vetores Genéticos/imunologia , Gorilla gorilla/virologia , Células HEK293 , Células HeLa , Humanos , Macaca , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Pandemias/prevenção & controle , Adulto Jovem
7.
Int J Mol Sci ; 22(2)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33418877

RESUMO

BACKGROUND: HER2-based retargeted viruses are in advanced phases of preclinical development of breast cancer models. Mesothelin (MSLN) is a cell-surface tumor antigen expressed in different subtypes of breast and non-breast cancer. Its recent identification as a marker of some triple-negative breast tumors renders it an attractive target, presently investigated in clinical trials employing antibody drug conjugates and CAR-T cells. The availability of MSLN-retargeted oncolytic viruses may complement the current immunotherapeutic panel of biological drugs against HER2-negative breast and non-breast tumors. METHODS: A fully virulent, tumor-targeted oncolytic Herpes simplex virus-1 (MSLN-THV) with a selectivity for mesothelin-expressing cancer cells was generated. Recombineering technology was used to replace an essential moiety of the viral glycoprotein D with antibody fragments derived from clinically validated MSLN monoclonal antibodies, and to allow IL12 cargo expression in infected cells. Panels of breast and female reproductive system cell lines were used to verify the oncolytic potential of the viral constructs. A platform for production of the retargeted viruses was developed in HEK 293 cells, providing stable expression of a suitable chimeric receptor. RESULTS: We demonstrated the selectivity of viral infection and cytotoxicity by MSLN-retargeted viruses in a panel of mesothelin-positive cancer cells, originating from breast and female reproductive system tumors. We also developed a second-generation oncolytic MSLN-THV, encoding IL12, to enhance the immunotherapeutic potential of the viral backbone. A non-tumor cell line expressing a chimeric MSLN/Nectin-1 receptor, de-sensitized from antiviral responses by genetic inactivation of the Stimulator of Interferon Genes (STING)-dependent pathway was engineered, to optimize viral yields. CONCLUSIONS: Our proof-of-concept study proposes MSLN-retargeted herpesviruses as potential cancer immunotherapeutics for assessments in preclinical models of MSLN-positive tumors, complementing the available panel of oncolytic viruses to HER2-negative breast tumors.


Assuntos
Proteínas Ligadas por GPI/metabolismo , Herpesvirus Humano 1/fisiologia , Terapia Viral Oncolítica/métodos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Edição de Genes , Células HEK293 , Herpesvirus Humano 1/genética , Humanos , Imunoterapia , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Mesotelina , Receptor ErbB-2/metabolismo
8.
PLoS Negl Trop Dis ; 14(7): e0008459, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32667913

RESUMO

Rabies, caused by RNA viruses in the Genus Lyssavirus, is the most fatal of all infectious diseases. This neglected zoonosis remains a major public health problem in developing countries, causing the death of an estimated 25,000-159,000 people each year, with more than half of them in children. The high incidence of human rabies in spite of effective vaccines is mainly linked to the lack of compliance with the complicated administration schedule, inadequacies of the community public health system for local administration by the parenteral route and the overall costs of the vaccine. The goal of our work was the development of a simple, affordable and effective vaccine strategy to prevent human rabies virus infection. This next generation vaccine is based on a replication-defective chimpanzee adenovirus vector belonging to group C, ChAd155-RG, which encodes the rabies glycoprotein (G). We demonstrate here that a single dose of this vaccine induces protective efficacy in a murine model of rabies challenge and elicits strong and durable neutralizing antibody responses in vaccinated non-human primates. Importantly, we demonstrate that one dose of a commercial rabies vaccine effectively boosts the neutralizing antibody responses induced by ChAd155-RG in vaccinated monkeys, showing the compatibility of the novel vectored vaccine with the current post-exposure prophylaxis in the event of rabies virus exposure. Finally, we demonstrate that antibodies induced by ChAd155-RG can also neutralize European bat lyssaviruses 1 and 2 (EBLV-1 and EBLV-2) found in bat reservoirs.


Assuntos
Adenovirus dos Símios/genética , Vacina Antirrábica/imunologia , Raiva/prevenção & controle , Animais , Antígenos Virais , Feminino , Vetores Genéticos/genética , Humanos , Macaca fascicularis , Camundongos , Pan troglodytes/virologia , Profilaxia Pós-Exposição , Coelhos , Vírus da Raiva/genética , Vírus da Raiva/imunologia , Sorogrupo , Vacinação , Vacinas Sintéticas/imunologia , Zoonoses
9.
Cancer Res ; 80(18): 3972-3982, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32690723

RESUMO

Tumors with microsatellite instability (MSI) are caused by a defective DNA mismatch repair system that leads to the accumulation of mutations within microsatellite regions. Indels in microsatellites of coding genes can result in the synthesis of frameshift peptides (FSP). FSPs are tumor-specific neoantigens shared across patients with MSI. In this study, we developed a neoantigen-based vaccine for the treatment of MSI tumors. Genetic sequences from 320 MSI tumor biopsies and matched healthy tissues in The Cancer Genome Atlas database were analyzed to select shared FSPs. Two hundred nine FSPs were selected and cloned into nonhuman Great Ape Adenoviral and Modified Vaccinia Ankara vectors to generate a viral-vectored vaccine, referred to as Nous-209. Sequencing tumor biopsies of 20 independent patients with MSI colorectal cancer revealed that a median number of 31 FSPs out of the 209 encoded by the vaccine was detected both in DNA and mRNA extracted from each tumor biopsy. A relevant number of peptides encoded by the vaccine were predicted to bind patient HLA haplotypes. Vaccine immunogenicity was demonstrated in mice with potent and broad induction of FSP-specific CD8 and CD4 T-cell responses. Moreover, a vaccine-encoded FSP was processed in vitro by human antigen-presenting cells and was subsequently able to activate human CD8 T cells. Nous-209 is an "off-the-shelf" cancer vaccine encoding many neoantigens shared across sporadic and hereditary MSI tumors. These results indicate that Nous-209 can induce the optimal breadth of immune responses that might achieve clinical benefit to treat and prevent MSI tumors. SIGNIFICANCE: These findings demonstrate the feasibility of an "off-the-shelf" vaccine for treatment and prevention of tumors harboring frameshift mutations and neoantigenic peptides as a result of microsatellite instability.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Neoplasias Colorretais/terapia , Imunogenicidade da Vacina/imunologia , Instabilidade de Microssatélites , Animais , Células Apresentadoras de Antígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Feminino , Mutação da Fase de Leitura , Humanos , Camundongos , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/imunologia
10.
Sci Transl Med ; 12(548)2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32554708

RESUMO

Strategies to enhance the induction of high magnitude T cell responses through vaccination are urgently needed. Major histocompatibility complex (MHC) class II-associated invariant chain (Ii) plays a critical role in antigen presentation, forming MHC class II peptide complexes for the generation of CD4+ T cell responses. Preclinical studies evaluating the fusion of Ii to antigens encoded in vector delivery systems have shown that this strategy may enhance T cell immune responses to the encoded antigen. We now assess this strategy in humans, using chimpanzee adenovirus 3 and modified vaccinia Ankara vectors encoding human Ii fused to the nonstructural (NS) antigens of hepatitis C virus (HCV) in a heterologous prime/boost regimen. Vaccination was well tolerated and enhanced the peak magnitude, breadth, and proliferative capacity of anti-HCV T cell responses compared to non-Ii vaccines in humans. Very high frequencies of HCV-specific T cells were elicited in humans. Polyfunctional HCV-specific CD8+ and CD4+ responses were induced with up to 30% of CD3+CD8+ cells targeting single HCV epitopes; these were mostly effector memory cells with a high proportion expressing T cell activation and cytolytic markers. No volunteers developed anti-Ii T cell or antibody responses. Using a mouse model and in vitro experiments, we show that Ii fused to NS increases HCV immune responses through enhanced ubiquitination and proteasomal degradation. This strategy could be used to develop more potent HCV vaccines that may contribute to the HCV elimination targets and paves the way for developing class II Ii vaccines against cancer and other infections.


Assuntos
Vacinas Virais , Antígenos de Diferenciação de Linfócitos B/genética , Linfócitos T CD8-Positivos , Hepacivirus/genética , Antígenos de Histocompatibilidade Classe II , Humanos
11.
Nat Commun ; 10(1): 2688, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217437

RESUMO

Neoantigens (nAgs) are promising tumor antigens for cancer vaccination with the potential of inducing robust and selective T cell responses. Genetic vaccines based on Adenoviruses derived from non-human Great Apes (GAd) elicit strong and effective T cell-mediated immunity in humans. Here, we investigate for the first time the potency and efficacy of a novel GAd encoding multiple neoantigens. Prophylactic or early therapeutic vaccination with GAd efficiently control tumor growth in mice. In contrast, combination of the vaccine with checkpoint inhibitors is required to eradicate large tumors. Gene expression profile of tumors in regression shows abundance of activated tumor infiltrating T cells with a more diversified TCR repertoire in animals treated with GAd and anti-PD1 compared to anti-PD1. Data suggest that effectiveness of vaccination in the presence of high tumor burden correlates with the breadth of nAgs-specific T cells and requires concomitant reversal of tumor suppression by checkpoint blockade.


Assuntos
Adenoviridae/imunologia , Antineoplásicos Imunológicos/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Neoplasias/terapia , Vacinas Virais/uso terapêutico , Adenoviridae/genética , Animais , Antígenos de Neoplasias/imunologia , Antineoplásicos Imunológicos/farmacologia , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral/transplante , Terapia Combinada/métodos , Modelos Animais de Doenças , Feminino , Humanos , Imunoterapia/métodos , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/imunologia , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/uso terapêutico , Vacinas Virais/genética , Vacinas Virais/imunologia
12.
Sci Rep ; 8(1): 585, 2018 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-29330364

RESUMO

A promising emerging area for the treatment of obesity and diabetes is combinatorial hormone therapy, where single-molecule peptides are rationally designed to integrate the complementary actions of multiple endogenous metabolically-related hormones. We describe here a proof-of-concept study on developing unimolecular polypharmacy agents through the use of selection methods based on phage-displayed peptide libraries (PDL). Co-agonists of the glucagon (GCG) and GLP-1 receptors were identified from a PDL sequentially selected on GCGR- and GLP1R-overexpressing cells. After two or three rounds of selection, 7.5% of randomly picked clones were GLP1R/GCGR co-agonists, and a further 1.53% were agonists of a single receptor. The phages were sequenced and 35 corresponding peptides were synthesized. 18 peptides were potent co-agonists, 8 of whom showed EC50 ≤ 30 pM on each receptor, comparable to the best rationally designed co-agonists reported in the literature. Based on literature examples, two sequences were engineered to stabilize against dipeptidyl peptidase IV cleavage and prolong the in vivo half-life: the engineered peptides were comparably potent to the parent peptides on both receptors, highlighting the potential use of phage-derived peptides as therapeutic agents. The strategy described here appears of general value for the discovery of optimized polypharmacology paradigms across several metabolically-related hormones.


Assuntos
Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Peptídeos/síntese química , Peptídeos/farmacologia , Receptores de Glucagon/agonistas , Diabetes Mellitus/tratamento farmacológico , Dipeptidil Peptidase 4/metabolismo , Humanos , Obesidade/tratamento farmacológico , Biblioteca de Peptídeos , Peptídeos/genética , Polimedicação , Análise de Sequência de DNA
13.
Mol Cancer Ther ; 15(6): 1177-89, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26960983

RESUMO

Aberrant activation of the Hedgehog (Hh) signaling pathway is implicated in the pathogenesis of many cancers, including medulloblastoma and basal cell carcinoma (BCC). In this study, using neonatally irradiated Ptch1(+/-) mice as a model of Hh-dependent tumors, we investigated the in vivo effects of MK-4101, a novel SMO antagonist, for the treatment of medulloblastoma and BCC. Results clearly demonstrated a robust antitumor activity of MK-4101, achieved through the inhibition of proliferation and induction of extensive apoptosis in tumor cells. Of note, beside antitumor activity on transplanted tumors, MK-4101 was highly efficacious against primary medulloblastoma and BCC developing in the cerebellum and skin of Ptch1(+/-) mice. By identifying the changes induced by MK-4101 in gene expression profiles in tumors, we also elucidated the mechanism of action of this novel, orally administrable compound. MK-4101 targets the Hh pathway in tumor cells, showing the maximum inhibitory effect on Gli1 MK-4101 also induced deregulation of cell cycle and block of DNA replication in tumors. Members of the IGF and Wnt signaling pathways were among the most highly deregulated genes by MK-4101, suggesting that the interplay among Hh, IGF, and Wnt is crucial in Hh-dependent tumorigenesis. Altogether, the results of this preclinical study support a therapeutic opportunity for MK-4101 in the treatment of Hh-driven cancers, also providing useful information for combination therapy with drugs targeting pathways cooperating with Hh oncogenic activity. Mol Cancer Ther; 15(6); 1177-89. ©2016 AACR.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/síntese química , Carcinoma Basocelular/tratamento farmacológico , Neoplasias Cerebelares/tratamento farmacológico , Proteínas Hedgehog/antagonistas & inibidores , Isoxazóis/administração & dosagem , Isoxazóis/síntese química , Meduloblastoma/tratamento farmacológico , Triazóis/administração & dosagem , Triazóis/síntese química , Animais , Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Cerebelares/metabolismo , Humanos , Isoxazóis/farmacologia , Meduloblastoma/metabolismo , Camundongos , Transplante de Neoplasias , Distribuição Aleatória , Transdução de Sinais/efeitos dos fármacos , Triazóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Pept Sci ; 21(9): 743-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26292842

RESUMO

Immunoadhesins are engineered proteins combining the constant domain (Fc) of an antibody with a ligand-binding (adhesion) domain. They have significant potential as therapeutic agents, because they maintain the favourable pharmacokinetics of antibodies with an expanded repertoire of ligand-binding domains: proteins, peptides, or small molecules. We have recently reported that the addition of a cholesterol group to two HIV antibodies can dramatically improve their antiviral potency. Cholesterol, which can be conjugated at various positions in the antibody, including the constant (Fc) domain, endows the conjugate with affinity for the membrane lipid rafts, thus increasing its concentration at the site where viral entry occurs. Here, we extend this strategy to an HIV immunoadhesin, combining a cholesterol-conjugated Fc domain with the peptide fusion inhibitor C41. The immunoadhesin C41-Fc-chol displayed high affinity for Human Embryonic Kidney (HEK) 293 cells, and when tested on a panel of HIV-1 strains, it was considerably more potent than the unconjugated C41-Fc construct. Potentiation of antiviral activity was comparable to what was previously observed for the cholesterol-conjugated HIV antibodies. Given the key role of cholesterol in lipid raft formation and viral fusion, we expect that the same strategy should be broadly applicable to enveloped viruses, for many of which it is already known the sequence of a peptide fusion inhibitor similar to C41. Moreover, the sequence of heptad repeat-derived fusion inhibitors can often be predicted from genomic information alone, opening a path to immunoadhesins against emerging viruses.


Assuntos
Antivirais/química , Colesterol/química , Peptídeos/química , Antivirais/farmacologia , Desenho de Fármacos , Células HEK293 , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Humanos , Peptídeos/farmacologia , Internalização do Vírus/efeitos dos fármacos
15.
PLoS One ; 5(7): e11742, 2010 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-20668533

RESUMO

Despite the wide use of cell lines in cancer research, the extent to which their surface properties correspond to those of primary tumors is poorly characterized. The present study addresses this problem from a transcriptional standpoint, analyzing the expression of membrane protein genes--the Membranome--in primary tumors and immortalized in-vitro cultured tumor cells. 409 human samples, deriving from ten independent studies, were analyzed. These comprise normal tissues, primary tumors and tumor derived cell lines deriving from eight different tissues: brain, breast, colon, kidney, leukemia, lung, melanoma, and ovary. We demonstrated that the Membranome has greater power than the remainder of the transcriptome when used as input for the automatic classification of tumor samples. This feature is maintained in tumor derived cell lines. In most cases primary tumors show maximal similarity in Membranome expression with cell lines of same tissue origin. Differences in Membranome expression between tumors and cell lines were analyzed also at the pathway level and biological themes were identified that were differentially regulated in the two settings. Moreover, by including normal samples in the analysis, we quantified the degree to which cell lines retain the Membranome up- and down-regulations observed in primary tumors with respect to their normal counterparts. We showed that most of the Membranome up-regulations observed in primary tumors are lost in the in-vitro cultured cells. Conversely, the majority of Membranome genes down-regulated upon tumor transformation maintain lower expression levels also in the cell lines. This study points towards a central role of Membranome genes in the definition of the tumor phenotype. The comparative analysis of primary tumors and cell lines identifies the limits of cell lines as a model for the study of cancer-related processes mediated by the cell surface. Results presented allow for a more rational use of the cell lines as a model of cancer.


Assuntos
Membrana Celular/genética , Neoplasias/genética , Linhagem Celular , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Técnicas In Vitro , Análise de Sequência com Séries de Oligonucleotídeos
16.
BMC Cancer ; 10: 129, 2010 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-20374648

RESUMO

BACKGROUND: Prostate stem cell antigen (PSCA) is a glycosylphosphatidylinositol (GPI) anchored protein expressed not only in prostate but also in pancreas and bladder cancer as shown by immunohistochemistry and mRNA analysis. It has been targeted by monoclonal antibodies in preclinical animal models and more recently in a clinical trial in prostate cancer patients. The biological role played in tumor growth is presently unknown. In this report we have characterized the contribution of PSCA expression to tumor growth. METHODS: A bladder cell line was engineered to express a doxycycline (dox) regulated shRNA against PSCA. To shed light on the PSCA biological role in tumor growth, microarray analysis was carried out as a function of PSCA expression. Expression of gene set of interest was further analyzed by qPCR RESULTS: Down regulation of the PSCA expression was associated with reduced cell proliferation in vitro and in vivo. Mice bearing subcutaneous tumors showed a reduced tumor growth upon treatment with dox, which effectively induced shRNA against PSCA as revealed by GFP expression. Pathway analysis of deregulated genes suggests a statistical significant association between PSCA downregulation and activation of genes downstream of the IFNalpha/beta receptor. CONCLUSIONS: These experiments established for the first time a correlation between the level of PSCA expression and tumor growth and suggest a role of PSCA in counteracting the natural immune response.


Assuntos
Glicoproteínas de Membrana/biossíntese , Proteínas de Neoplasias/biossíntese , Neoplasias da Bexiga Urinária/patologia , Animais , Antígenos de Neoplasias , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Células Clonais , Regulação para Baixo , Doxiciclina/farmacologia , Feminino , Proteínas Ligadas por GPI , Humanos , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Reação em Cadeia da Polimerase , Interferência de RNA , Transdução de Sinais/imunologia , Transcrição Gênica , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/metabolismo
17.
BMC Genomics ; 10: 135, 2009 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-19327144

RESUMO

BACKGROUND: Spontaneous tumors in dog have been demonstrated to share many features with their human counterparts, including relevant molecular targets, histological appearance, genetics, biological behavior and response to conventional treatments. Mammary tumors in dog therefore provide an attractive alternative to more classical mouse models, such as transgenics or xenografts, where the tumour is artificially induced. To assess the extent to which dog tumors represent clinically significant human phenotypes, we performed the first genome-wide comparative analysis of transcriptional changes occurring in mammary tumors of the two species, with particular focus on the molecular pathways involved. RESULTS: We analyzed human and dog gene expression data derived from both tumor and normal mammary samples. By analyzing the expression levels of about ten thousand dog/human orthologous genes we observed a significant overlap of genes deregulated in the mammary tumor samples, as compared to their normal counterparts. Pathway analysis of gene expression data revealed a great degree of similarity in the perturbation of many cancer-related pathways, including the 'PI3K/AKT', 'KRAS', 'PTEN', 'WNT-beta catenin' and 'MAPK cascade'. Moreover, we show that the transcriptional relationships between different gene signatures observed in human breast cancer are largely maintained in the canine model, suggesting a close interspecies similarity in the network of cancer signalling circuitries. CONCLUSION: Our data confirm and further strengthen the value of the canine mammary cancer model and open up new perspectives for the evaluation of novel cancer therapeutics and the development of prognostic and diagnostic biomarkers to be used in clinical studies.


Assuntos
Neoplasias da Mama/genética , DNA de Neoplasias/genética , Perfilação da Expressão Gênica , Neoplasias Mamárias Animais/genética , Animais , Análise por Conglomerados , Hibridização Genômica Comparativa , Biologia Computacional , Modelos Animais de Doenças , Doenças do Cão/genética , Cães , Regulação Neoplásica da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Componente Principal
18.
PLoS One ; 3(1): e1508, 2008 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-18231595

RESUMO

A novel and efficient tagArray technology was developed that allows rapid identification of antibodies which bind to receptors with a specific expression profile, in the absence of biological information. This method is based on the cloning of a specific, short nucleotide sequence (tag) in the phagemid coding for each phage-displayed antibody fragment (phage-Ab) present in a library. In order to set up and validate the method we identified about 10,000 different phage-Abs binding to receptors expressed in their native form on the cell surface (10 k Membranome collection) and tagged each individual phage-Ab. The frequency of each phage-Ab in a given population can at this point be inferred by measuring the frequency of its associated tag sequence through standard DNA hybridization methods. Using tiny amounts of biological samples we identified phage-Abs binding to receptors preferentially expressed on primary tumor cells rather than on cells obtained from matched normal tissues. These antibodies inhibited cell proliferation in vitro and tumor development in vivo, thus representing therapeutic lead candidates.


Assuntos
Anticorpos Monoclonais/genética , Bacteriófagos/genética , Análise de Sequência com Séries de Oligonucleotídeos , Animais , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/farmacocinética , Ensaio de Imunoadsorção Enzimática , Imunoglobulina G/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ressonância de Plasmônio de Superfície
19.
Source Code Biol Med ; 2: 4, 2007 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-17822555

RESUMO

BACKGROUND: The number of patents associated with genes and proteins and the amount of information contained in each patent often present a real obstacle to the rapid evaluation of the novelty of findings associated to genes from an intellectual property (IP) perspective. This assessment, normally carried out by expert patent professionals, can therefore become cumbersome and time consuming. Here we present PatentMatrix, a novel software tool for the automated analysis of patent sequence text entries. METHODS AND RESULTS: PatentMatrix is written in the Awk language and requires installation of the Derwent GENESEQtrade mark patent sequence database under the sequence retrieval system SRS.The software works by taking as input two files: i) a list of genes or proteins with the associated GENESEQtrade mark patent sequence accession numbers ii) a list of keywords describing the research context of interest (e.g. 'lung', 'cancer', 'therapeutics', 'diagnostics'). The GENESEQtrade mark database is interrogated through the SRS system and each patent entry of interest is screened for the occurrence of user-defined keywords. Moreover, the software extracts the basic information useful for a preliminary assessment of the IP coverage of each patent from the GENESEQtrade mark database. As output, two tab-delimited files are generated which provide the user with a detailed and an aggregated view of the results.An example is given where the IP position of five genes is evaluated in the context of 'development of antibodies for cancer treatment' CONCLUSION: PatentMatrix allows a rapid survey of patents associated with genes or proteins in a particular area of interest as defined by keywords. It can be efficiently used to evaluate the IP-related novelty of scientific findings and to rank genes or proteins according to their IP position.

20.
J Med Chem ; 49(18): 5404-7, 2006 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-16942012

RESUMO

A strategy to obtain a fully orthogonal estrogen-receptor-based gene switch responsive to molecules with acceptable pharmacological properties is presented. From a series of tetrahydrofluorenones active on the wild-type estrogen receptor (ER) an inactive analogue is chosen as a new lead compound. Coevolution of receptor mutants and ligands leads to an ER-based gene switch suitable for studies in animal models.


Assuntos
Fluorenos/síntese química , Receptores de Estrogênio/efeitos dos fármacos , Sítios de Ligação , Estradiol/química , Receptor alfa de Estrogênio/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/efeitos dos fármacos , Receptor beta de Estrogênio/genética , Fluorenos/química , Fluorenos/farmacologia , Células HeLa , Humanos , Ligantes , Modelos Moleculares , Estrutura Molecular , Mutação , Receptores de Estrogênio/genética , Relação Estrutura-Atividade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA