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1.
J Virol ; 93(11)2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30918073

RESUMO

In this article we report that the M2 protein encoded by the vaccinia virus is secreted as a homo-oligomer by infected cells and binds two central costimulation molecules, CD80 (B7-1) and CD86 (B7-2). These interactions block the ligation of the two B7 proteins to both soluble CD28 and soluble cytotoxic T-lymphocyte associated protein 4 (CTLA4) but favor the binding of soluble PD-L1 to soluble CD80. M2L gene orthologues are found in several other poxviruses, and the B7-CD28/CTLA4 blocking activity has been identified for several culture supernatants of orthopoxvirus-infected cells and for a recombinant myxoma virus M2 protein homolog (i.e., Gp120-like protein, or Gp120LP). Overall, these data indicate that the M2 poxvirus family of proteins may be involved in immunosuppressive activities broader than the NF-κB inhibition already reported (R. Gedey, X. L. Jin, O. Hinthong, and J. L. Shisler, J Virol 80:8676-8685, 2006, https://doi.org/10.1128/JVI.00935-06). A Copenhagen vaccinia virus with a deletion of the nonessential M2L locus was generated and compared with its parental virus. This M2L-deleted vaccinia virus, unlike the parental virus, does not generate interference with the B7-CD28/CTLA4/PD-L1 interactions. Moreover, this deletion did not affect any key features of the virus (in vitro replication, oncolytic activities in vitro and in vivo, and intratumoral expression of a transgene in an immunocompetent murine model). Altogether, these first results suggest that the M2 protein has the potential to be used as a new immunosuppressive biotherapeutic and that the M2L-deleted vaccinia virus represents an attractive new oncolytic platform with an improved immunological profile.IMPORTANCE The vaccinia virus harbors in its genome several genes dedicated to the inhibition of the host immune response. Among them, M2L was reported to inhibit the intracellular NF-κB pathway. We report here several new putative immunosuppressive activities of M2 protein. M2 protein is secreted and binds cornerstone costimulatory molecules (CD80/CD86). M2 binding to CD80/CD86 blocks their interaction with soluble CD28/CTLA4 but also favors the soluble PD-L1-CD80 association. These findings open the way for new investigations deciphering the immune system effects of soluble M2 protein. Moreover, a vaccinia virus with a deletion of its M2L has been generated and characterized as a new oncolytic platform. The replication and oncolytic activities of the M2L-deleted vaccinia virus are indistinguishable from those of the parental virus. More investigations are needed to characterize in detail the immune response triggered against both the tumor and the virus by this M2-defective vaccinia virus.


Assuntos
Antígeno B7-1/metabolismo , Antígeno B7-H1/metabolismo , Vaccinia virus/metabolismo , Animais , Antígenos CD/metabolismo , Antígeno B7-1/genética , Antígeno B7-2/genética , Antígeno B7-2/metabolismo , Antígenos CD28/metabolismo , Antígeno CTLA-4/metabolismo , Moléculas de Adesão Celular , Linhagem Celular , Embrião de Galinha , Humanos , Imunoconjugados , Interleucina-2/metabolismo , Ativação Linfocitária/imunologia , Glicoproteínas de Membrana/metabolismo , Camundongos , NF-kappa B/metabolismo , Vacínia/genética , Vacínia/metabolismo , Vaccinia virus/genética , Proteínas Virais/metabolismo
2.
Clin Transl Immunology ; 11(5): e1392, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35573979

RESUMO

Objective: Antitumor viral vaccines, and more particularly poxviral vaccines, represent an active field for clinical development and translational research. To improve the efficacy and treatment outcome, new viral vectors are sought, with emphasis on their abilities to stimulate innate immunity, to display tumor antigens and to induce a specific T-cell response. Methods: We screened for a new poxviral backbone with improved innate and adaptive immune stimulation using IFN-α secretion levels in infected PBMC cultures as selection criteria. Assessment of virus effectiveness was made in vitro and in vivo. Results: The bovine pseudocowpox virus (PCPV) stood out among several poxviruses for its ability to induce significant secretion of IFN-α. PCPV produced efficient activation of human monocytes and dendritic cells, degranulation of NK cells and reversed MDSC-induced T-cell suppression, without being offensive to activated T cells. A PCPV-based vaccine, encoding the HPV16 E7 protein (PCPV-E7), stimulated strong antigen-specific T-cell responses in TC1 tumor-bearing mice. Complete regression of tumors was obtained in a CD8+ T-cell-dependent manner after intratumoral injection of PCPV-E7, followed by intravenous injection of the cancer vaccine MVA-E7. PCPV also proved active when injected repeatedly intratumorally in MC38 tumor-bearing mice, generating tumor-specific T-cell responses without encoding a specific MC38 antigen. From a translational perspective, we demonstrated that PCPV-E7 effectively stimulated IFN-γ production by T cells from tumor-draining lymph nodes of HPV+-infected cancer patients. Conclusion: We propose PCPV as a viral vector suitable for vaccination in the field of personalised cancer vaccines, in particular for heterologous prime-boost regimens.

3.
Breast Care (Basel) ; 15(3): 236-245, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32774217

RESUMO

BACKGROUND: Breast cancer patients' self-understanding of their disease can impact their quality of life (QoL); the relationship between compliance and QoL is poorly understood. PATIENTS AND METHODS: The Patient's Anastrozole Compliance to Therapy (PACT) program, a prospective, randomized study, investigated the effect of additional patient information material (IM) packages on compliance with adjuvant aromatase inhibitor (AI) therapy in postmenopausal women with hormone receptor-positive early breast cancer. The QoL subanalysis presented here examined the impact of IM packages on QoL and the association between QoL and compliance. European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and QLQ-BR23 questionnaires were completed at baseline, 12 and 24 months, or study termination to assess health-related QoL and disease-related symptoms. RESULTS: Of the 4,844 patients randomized to standard therapy or standard therapy + IM packages (1:1), 4,253 were available for QoL analysis. No difference in QoL was observed between groups at baseline. IM packages did not have a statistically significant impact on patient QoL at the 12- or 24-month follow-up. Compliant patients experienced improvement in multiple items across the QLQ-C30 and QLQ-BR23 scales at 12 months. However, those results should be interpreted carefully due to limitations in the statistical analyses. CONCLUSIONS: Provision of IM packages did not influence patients' QoL or satisfaction with care during AI therapy. Compliant patients appear to experience improved QoL compared to noncompliant patients, perhaps indicating a more self-empowered perception of their condition.

4.
Biomedicines ; 8(12)2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33256205

RESUMO

As a live biologic agent, oncolytic vaccinia virus has the ability to target and selectively amplify at tumor sites. We have previously reported that deletion of thymidine kinase and ribonucleotide reductase genes in vaccinia virus can increase the safety and efficacy of the virus. Here, to allow direct visualization of the viral genome in living cells, we incorporated the ANCH target sequence and the OR3-Santaka gene in the double-deleted vaccinia virus. Infection of human tumor cells with ANCHOR3-tagged vaccinia virus enables visualization and quantification of viral genome dynamics in living cells. The results show that the ANCHOR technology permits the measurement of the oncolytic potential of the double deleted vaccinia virus. Quantitative analysis of infection kinetics and of viral DNA replication allow rapid and efficient identification of inhibitors and activators of oncolytic activity. Our results highlight the potential application of the ANCHOR technology to track vaccinia virus and virtually any kind of poxvirus in living cells.

5.
NPJ Vaccines ; 5(1): 39, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32435513

RESUMO

Tuberculosis (TB) still is the principal cause of death from infectious disease and improved vaccination strategies are required to reduce the disease burden and break TB transmission. Here, we investigated different routes of administration of vectored subunit vaccines based on chimpanzee-derived adenovirus serotype-3 (ChAd3) for homologous prime-boosting and modified vaccinia virus Ankara (MVA) for heterologous boosting with both vaccine vectors expressing the same antigens from Mycobacterium tuberculosis (Ag85B, ESAT6, Rv2626, Rv1733, RpfD). Prime-boost strategies were evaluated for immunogenicity and protective efficacy in highly susceptible rhesus macaques. A fully parenteral administration regimen was compared to exclusive respiratory mucosal administration, while parenteral ChAd3-5Ag prime-boosting and mucosal MVA-5Ag boosting were applied as a push-and-pull strategy from the periphery to the lung. Immune analyses corroborated compartmentalized responses induced by parenteral versus mucosal vaccination. Despite eliciting TB-specific immune responses, none of the investigational regimes conferred a protective effect by standard readouts of TB compared to non-vaccinated controls, while lack of protection by BCG underpinned the stringency of this non-human primate test modality. Yet, TB manifestation after full parenteral vaccination was significantly less compared to exclusive mucosal vaccination.

6.
Hum Vaccin Immunother ; 14(6): 1417-1422, 2018 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-29388874

RESUMO

Pre-clinical models mimicking persistent hepatitis B virus (HBV) expression are seldom, do not capture all features of a human chronic infection and due to their complexity, are subject to variability. We report a meta-analysis of seven experiments performed with TG1050, an HBV-targeted immunotherapeutic, 1 in an HBV-persistent mouse model based on the transduction of mice by an adeno-associated virus coding for an infectious HBV genome (AAV-HBV). To mimic the clinical diversity seen in HBV chronically infected patients, AAV-HBV transduced mice displaying variable HBsAg levels were treated with TG1050. Overall mean percentages of responder mice, displaying decrease in important clinical parameters i.e. HBV-DNA (viremia) and HBsAg levels, were 52% and 51% in TG1050 treated mice, compared with 8% and 22%, respectively, in untreated mice. No significant impact of HBsAg level at baseline on response to TG1050 treatment was found. TG1050-treated mice displayed a significant shorter Time to Response (decline in viral parameters) with an Hazard Ratio (HR) of 8.3 for viremia and 2.6 for serum HBsAg. The mean predicted decrease for TG1050-treated mice was 0.5 log for viremia and 0.8 log for HBsAg, at the end of mice follow-up, compared to no decrease for viremia and 0.3 log HBsAg decrease for untreated mice. For mice receiving TG1050, a higher decline of circulating viremia and serum HBsAg level over time was detected by interaction term meta-analysis with a significant treatment effect (p = 0.002 and p<0.001 respectively). This meta-analysis confirms the therapeutic value of TG1050, capable of exerting potent antiviral effects in an HBV-persistent model mimicking clinical situations.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/terapia , Fatores Imunológicos/uso terapêutico , Animais , DNA Viral/sangue , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Antígenos de Superfície da Hepatite B/sangue , Camundongos Endogâmicos C57BL , Resultado do Tratamento , Carga Viral
7.
PLoS One ; 13(5): e0196815, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29718990

RESUMO

Despite the existence of the prophylactic Bacille Calmette-Guérin (BCG) vaccine, infection by Mycobacterium tuberculosis (Mtb) remains a major public health issue causing up to 1.8 million annual deaths worldwide. Increasing prevalence of Mtb strains resistant to antibiotics represents an urgent threat for global health that has prompted a search for alternative treatment regimens not subject to development of resistance. Immunotherapy constitutes a promising approach to improving current antibiotic treatments through engagement of the host's immune system. We designed a multi-antigenic and multiphasic vaccine, based on the Modified Vaccinia Ankara (MVA) virus, denoted MVATG18598, which expresses ten antigens classically described as representative of each of different phases of Mtb infection. In vitro analysis coupled with multiple-passage evaluation demonstrated that this vaccine is genetically stable, i.e. fit for manufacturing. Using different mouse strains, we show that MVATG18598 vaccination results in both Th1-associated T-cell responses and cytolytic activity, targeting all 10 vaccine-expressed Mtb antigens. In chronic post-exposure mouse models, MVATG18598 vaccination in combination with an antibiotic regimen decreases the bacterial burden in the lungs of infected mice, compared with chemotherapy alone, and is associated with long-lasting antigen-specific Th1-type T cell and antibody responses. In one model, co-treatment with MVATG18598 prevented relapse of the disease after treatment completion, an important clinical goal. Overall, results demonstrate the capacity of the therapeutic MVATG18598 vaccine to improve efficacy of chemotherapy against TB. These data support further development of this novel immunotherapeutic in the treatment of Mtb infections.


Assuntos
Antituberculosos/uso terapêutico , Mycobacterium tuberculosis/efeitos dos fármacos , Vacinas Virais/uso terapêutico , Quimioterapia Combinada , Ensaio de Imunoadsorção Enzimática , Humanos , Resultado do Tratamento , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Vacinas de DNA , Vacinas Virais/genética
8.
Oncoimmunology ; 5(10): e1220467, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27853644

RESUMO

We report here the successful vectorization of a hamster monoclonal IgG (namely J43) recognizing the murine Programmed cell death-1 (mPD-1) in Western Reserve (WR) oncolytic vaccinia virus. Three forms of mPD-1 binders have been inserted into the virus: whole antibody (mAb), Fragment antigen-binding (Fab) or single-chain variable fragment (scFv). MAb, Fab and scFv were produced and assembled with the expected patterns in supernatants of cells infected by the recombinant viruses. The three purified mPD-1 binders were able to block the binding of mPD-1 ligand to mPD-1 in vitro. Moreover, mAb was detected in tumor and in serum of C57BL/6 mice when the recombinant WR-mAb was injected intratumorally (IT) in B16F10 and MCA 205 tumors. The concentration of circulating mAb detected after IT injection was up to 1,900-fold higher than the level obtained after a subcutaneous (SC) injection (i.e., without tumor) confirming the virus tropism for tumoral cells and/or microenvironment. Moreover, the overall tumoral accumulation of the mAb was higher and lasted longer after IT injection of WR-mAb1, than after IT administration of 10 µg of J43. The IT injection of viruses induced a massive infiltration of immune cells including activated lymphocytes (CD8+ and CD4+). Interestingly, in the MCA 205 tumor model, WR-mAb1 and WR-scFv induced a therapeutic control of tumor growth similar to unarmed WR combined to systemically administered J43 and superior to that obtained with an unarmed WR. These results pave the way for next generation of oncolytic vaccinia armed with immunomodulatory therapeutic proteins such as mAbs.

9.
Res Involv Engagem ; 1: 4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-29062493

RESUMO

PLAIN ENGLISH SUMMARY: Biobanks are collections of donations of biological material (DNA, cells, tissue etc.) and related data which are very valuable for research into human diseases. A variety of biobanks exist for example within hospitals, research institutes, pharmaceutical companies and patient organisations. The role of patients in biobanking is changing from being seen simply as donors, to actual collaborators in the design, development and the running of biobanks. In this article, we provide a number of examples of patients acting as partners at the heart of biobanking, where their voice and perspective is being seen and used as a valuable resource for the biobank. Our aim is that these examples can be used by those who work with patients in biobank-based research, to design future strategies for patient and public involvement in all biobanks. ABSTRACT: Biobanks and biobanking research plays an increasingly important role in healthcare research and delivery as health systems become more patient-centred and medicine becomes more personalised. There is also growing acceptance and appreciation of the value that patients, patient advocacy organisations and the public can bring as stakeholders in biobanking and more generally in research. Therefore, the importance of active, early and sustained engagement and involvement of patient and public representatives in biobanks will become increasingly relevant. Organising and facilitating patient and public involvement in biobanking takes considerable time and effort for all stakeholders involved. Therefore, for any biobank operator considering involving patients and the public in their biobanking activities, consideration of best practices, current guidance, ethical issues and evaluation of involvement will be important. In this article, we demonstrate that patients are much more than donors to biobanks-they are collaborators at the heart of biobanking with an important voice to identify perspective, which can be an extremely valuable resource for all biobanks to utilise. The case studies herein provide examples of good practice of patient involvement in biobanking as well as outcomes from these practices, and lessons learned. Our aim is to provide useful insights from these efforts and potential future strategies for the multiple stakeholders that work with patients and the public involved in biobank-based research.

10.
PLoS One ; 10(11): e0143552, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26599077

RESUMO

Bacille Calmette-Guérin (BCG) vaccination of new born babies can protect children against tuberculosis (TB), but fails to protect adults consistently against pulmonary TB underlying the urgent need to develop novel TB vaccines. Majority of first generation TB vaccine candidates have relied on a very limited number of antigens typically belonging to the active phase of infection. We have designed a multi-antigenic and multiphasic vaccine, based on the Modified Vaccinia Ankara virus (MVA). Up to fourteen antigens representative of the three phases of TB infection (active, latent and resuscitation) were inserted into MVA. Using three different strains of mouse (BALB/c, C57BL/6 and C3H/HeN), we show that a single vaccination results in induction of both CD4 and CD8 T cells, displaying capacity to produce multiple cytokines together with cytolytic activity targeting a large array of epitopes. As expected, dominance of responses was linked to the mouse haplotype although for a given haplotype, responses specific of at least one antigen per phase could always be detected. Vaccination of non-human primates with the 14 antigens MVA-TB candidate resulted in broad and potent cellular-based immunogenicity. The remarkable plasticity of MVA opens the road to development of a novel class of highly complex recombinant TB vaccines to be evaluated in both prophylactic and therapeutic settings.


Assuntos
Imunidade Celular , Vacinas contra a Tuberculose/imunologia , Tuberculose/imunologia , Vacinas Virais/imunologia , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Citocinas/metabolismo , Citotoxicidade Imunológica , Modelos Animais de Doenças , Interferon gama/biossíntese , Masculino , Camundongos , Mycobacterium bovis/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Tuberculose/prevenção & controle , Tuberculose/terapia , Vacinas contra a Tuberculose/genética , Vacinas de DNA , Vacinas Virais/genética
11.
Breast Care (Basel) ; 8(2): 110-20, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-24419247

RESUMO

BACKGROUND: The Patient's Anastrozole Compliance to Therapy (PACT) program is a large randomized study designed to assess whether the provision of educational materials (EM) could improve compliance with aromatase inhibitor therapy in postmenopausal women with early, hormone receptor-positive breast cancer. PATIENTS AND METHODS: The PACT study presented a large, homogeneous dataset. The baseline analysis included patient demographics and initial treatments and patient perceptions about treatment and quality of life. RESULTS: Overall, 4,923 patients were enrolled at 109 German breast cancer centers/clinics in cooperation with 1,361 office-based gynecologists/oncologists. 4,844 women were randomized 1:1 to standard therapy (n = 2,402) or standard therapy plus EM (n = 2,442). Prior breast-conserving surgery and mastectomy had been received by 76% and 24% of the patients, respectively. Radiotherapy was scheduled for 85% of the patients, adjuvant chemotherapy for 38%. Reflecting the postmenopausal, hormone-sensitive nature of this population, only 285 patients (7%) had received neoadjuvant chemotherapy. CONCLUSIONS: A comparison with epidemiological data from the West German Breast Center suggests that the patients in the PACT study are representative of a general postmenopausal early breast cancer population and that the findings may be applicable to 'real-world' Germany and beyond. Compliance data from PACT are eagerly anticipated.

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