RESUMO
Follicular lymphoma (FL) is a remarkably immune-responsive malignancy, which is still considered incurable. As, standard immunochemotherapy is complex, toxic and not curative, improvement in FL care is now a crucial topic in hemato-oncology. Recently, we and others have shown that dendritic cell (DC)-based therapies allow a specific immune response associated with sustained lymphoma regression in a proportion of low-tumor burden FL patients. Importantly, the rate of objective clinical response (33-50%) and of sustained remission is remarkably higher compared to similar studies in solid tumors, corroborating the assumption of the immune responsiveness of FL. Our experimental intra-tumoral strategy combined injection with rituximab and interferon-α-derived dendritic cells (IFN-DC), a novel DC population particularly efficient in biasing T-helper response toward the Th1 type and in the cross-priming of CD8 + T cells. Noteworthy, intra-tumoral injection of DC is a new therapeutic option based on the assumption that following the induction of cancer-cell immunogenic death, unloaded DC would phagocytize in vivo the tumor associated antigens and give rise to a specific immune response. This approach allows the design of easy and inexpensive schedules. On the other hand, advanced and straightforward methods to produce clinical-grade antigenic formulations are currently under development. Both unloaded DC strategies and DC-vaccines are suited for combination with radiotherapy, immune checkpoint inhibitors, immunomodulators and metronomic chemotherapy. In fact, studies in animal models have already shown impressive results, while early-phase combination trials are ongoing. Here, we summarize the recent advances and the future perspectives of DC-based therapies in the treatment of FL patients.
Assuntos
Células Dendríticas/imunologia , Imunoterapia/métodos , Linfoma Folicular/tratamento farmacológico , Linfoma Folicular/imunologia , Humanos , Linfoma Folicular/patologiaRESUMO
The perspective of combining cancer vaccines with immunomodulatory drugs is currently regarded as a highly promising approach for boosting tumor-specific T cell immunity and eradicating residual malignant cells. The efficacy of dendritic cell (DC) vaccination in combination with lenalidomide, an anticancer drug effective in several hematologic malignancies, was investigated in a follicular lymphoma (FL) model. First, we evaluated the in vitro activity of lenalidomide in modulating the immune responses of lymphocytes co-cultured with a new DC subset differentiated with IFN-α (IFN-DC) and loaded with apoptotic lymphoma cells. We next evaluated the efficacy of lenalidomide and IFN-DC-based vaccination, either alone or in combination, in hu-PBL-NOD/SCID mice bearing established human lymphoma. We found that lenalidomide reduced Treg frequency and IL-10 production in vitro, improved the formation of immune synapses of CD8 + lymphocytes with lymphoma cells and enhanced anti-lymphoma cytotoxicity. Treatment of lymphoma-bearing mice with either IFN-DC vaccination or lenalidomide led to a significant decrease in tumor growth and lymphoma cell spread. Lenalidomide treatment was shown to substantially inhibit tumor-induced neo-angiogenesis rather than to exert a direct cytotoxic effect on lymphoma cells. Notably, the combined treatment with the vaccine plus lenalidomide was more effective than either single treatment, resulting in the significant regression of established tumors and delayed tumor regrowth upon treatment discontinuation. In conclusion, our data demonstrate that IFN-DC-based vaccination plus lenalidomide exert an additive therapeutic effect in xenochimeric mice bearing established lymphoma. These results may pave the way to evaluate this combination in the clinical ground.
Assuntos
Vacinas Anticâncer/administração & dosagem , Células Dendríticas/imunologia , Sinergismo Farmacológico , Fatores Imunológicos/imunologia , Interferon-alfa/imunologia , Lenalidomida/farmacologia , Linfoma Folicular/terapia , Animais , Terapia Combinada , Feminino , Humanos , Fatores Imunológicos/farmacologia , Linfoma Folicular/imunologia , Linfoma Folicular/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCIDRESUMO
Follicular lymphoma (FL) is the most common form of indolent non-Hodgkin lymphoma. This malignancy is considered virtually incurable, with high response rates to therapy but frequent relapses. We investigated the ability of monocyte-derived dendritic cells generated in the presence of IFN-α and GM-CSF (IFN-DC) and loaded with apoptotic lymphoma cells to activate immune responses against FL cells, with the ultimate goal of designing novel patient-specific vaccination strategies for the treatment of FL. In this article, we show that apoptotic tumor cell-loaded IFN-DC from FL patients, which were cultured for 2 wk with autologous lymphocytes, led to Th1 response skewing, based on significantly higher levels of IFN-γ production and a remarkable increase in CD8(+) and NK cell frequency, consistent with the detection of enhanced cytotoxic effector function toward autologous FL cells. IFN-DC were found to promote efficient NK cell activation, increased expression of cytotoxicity receptors, and extensive IFN-γ production in the virtual absence of IL-10. Moreover, direct recognition and killing of primary autologous lymphoma cells by activated NK cells from FL patients was also demonstrated. A critical role was demonstrated for MHC class I-related chain A and B and membrane-bound IL-15 in IFN-DC-mediated NK cell activation and early IFN-γ production. The overall results indicate that IFN-DC loaded with autologous apoptotic FL cells represent a valuable tool for improving the potency of therapeutic cancer vaccines through the efficient induction of NK cell activation and promotion of CD8(+) T cell antitumor immunity.
Assuntos
Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Células Matadoras Naturais/imunologia , Ativação Linfocitária/imunologia , Linfoma Folicular , Apoptose/imunologia , Western Blotting , Técnicas de Cocultura , Citotoxicidade Imunológica , ELISPOT , Citometria de Fluxo , Humanos , Interferon-alfa/imunologia , Células Tumorais CultivadasRESUMO
Cross-presentation allows antigen-presenting cells to present exogenous antigens to CD8(+) T cells, playing an essential role in controlling infections and tumor development. IFN-α induces the rapid differentiation of human mono-cytes into dendritic cells, known as IFN-DCs, highly efficient in mediating cross-presentation, as well as the cross-priming of CD8(+) T cells. Here, we have investigated the mechanisms underlying the cross-presentation ability of IFN-DCs by studying the intracellular sorting of soluble ovalbumin and nonstructural-3 protein of hepatitis C virus. Our results demonstrate that, independently from the route and mechanism of antigen entry, IFN-DCs are extraordinarily competent in preserving internalized proteins from early degradation and in routing antigens toward the MHC class-I processing pathway, allowing long-lasting, cross-priming capacity. In IFN-DCs, both early and recycling endosomes function as key compartments for the storage of both antigens and MHC-class I molecules and for proteasome- and transporter-associated with Ag processing-dependent auxiliary cross-presentation pathways. Because IFN-DCs closely resemble human DCs naturally occurring in vivo in response to infections and other danger signals, these findings may have important implications for the design of vaccination strategies in neoplastic or chronic infectious diseases.
Assuntos
Antígenos/metabolismo , Apresentação Cruzada/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Interferon-alfa/farmacologia , Antígenos/imunologia , Western Blotting , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Células Cultivadas , Apresentação Cruzada/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Endossomos/química , Endossomos/metabolismo , Citometria de Fluxo , Hepacivirus/imunologia , Hepacivirus/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Microscopia Confocal , Ovalbumina/imunologia , Ovalbumina/metabolismo , Ovalbumina/farmacocinética , Proteínas não Estruturais Virais/imunologia , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/farmacocinéticaRESUMO
A major challenge of AIDS research is the development of therapeutic vaccine strategies capable of inducing the humoral and cellular arms of the immune responses against HIV-1. In this work, we evaluated the capability of DCs pulsed with aldrithiol-2-inactivated HIV-1 in inducing a protective antiviral human immune response in SCID mice reconstituted with human PBL (hu-PBL-SCID mice). Immunization of hu-PBL-SCID mice with DCs generated after exposure of monocytes to GM-CSF/IFN-alpha (IFN-DCs) and pulsed with inactivated HIV-1 resulted in a marked induction of human anti-HIV-1 antibodies, which was associated with the detection of anti-HIV neutralizing activity in the serum. This vaccination schedule also promoted the generation of a human CD8+ T cell response against HIV-1, as measured by IFN-gamma Elispot analysis. Notably, when the hu-PBL-SCID mice immunized with antigen-pulsed IFN-DCs were infected with HIV-1, inhibition of virus infection was observed as compared with control animals. These results suggest that IFN-DCs pulsed with inactivated HIV-1 can represent a valuable approach of immune intervention in HIV-1-infected patients.
Assuntos
Vacinas contra a AIDS/uso terapêutico , Síndrome da Imunodeficiência Adquirida/imunologia , Células Dendríticas/imunologia , HIV-1/imunologia , Interferon-alfa/imunologia , Linfócitos/imunologia , Vacinas de Produtos Inativados/uso terapêutico , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Animais , Células Dendríticas/transplante , Células Dendríticas/virologia , Humanos , Separação Imunomagnética/métodos , Transfusão de Linfócitos , Linfócitos/citologia , Camundongos , Camundongos SCID , Transplante Heterólogo/imunologiaRESUMO
PURPOSE: This study was aimed at evaluating the feasibility, safety, immunologic and clinical responses in patients with follicular lymphoma treated with monocyte-derived dendritic cells generated in the presence of IFNα and GM-CSF (IFN-DC) in combination with low doses of rituximab. PATIENTS AND METHODS: Firstly, we analyzed in vitro and in vivo the immunologic properties of IFN-DC against follicular lymphoma. Thus, we performed a phase I trial in 8 patients with refractory and relapsed follicular lymphoma based on sequential intranodal injections of low-dose of rituximab and unloaded IFN-DC and report the safety, clinical, and immunologic results of the enrolled patients. RESULTS: Preclinical studies indicated that IFN-DC can synergize with rituximab leading to increased cytotoxicity and T-cell tumor infiltration. The clinical evaluation showed that the combined treatment was totally safe. The overall response rate was 50%, PET-negative complete response rate 37%, and remission is still ongoing in 2/4 of responding patients (median follow-up 26 months, range 11-47). Notably, following the combined therapy all patients showed induction/enhancement of T-cell responses by CD107 degranulation or IFNγ ELISPOT assay against patient-specific tumor IGHV sequences. CONCLUSIONS: These results represent the proof-of-principle on the effectiveness of unloaded IFN-DC in inducing durable clinical responses and promoting induction of tumor-specific peripheral T cells, thus suggesting the occurrence of an effective endogenous antitumor vaccination. The overall findings indicate that some unique properties of IFN-DC can be successfully exploited to induce/enhance antitumor responses, thus representing a valuable antitumor strategy for novel and more effective combination therapies in patients with cancer.
Assuntos
Células Dendríticas/transplante , Imunoterapia Adotiva/métodos , Linfoma Folicular/terapia , Recidiva Local de Neoplasia/terapia , Rituximab/administração & dosagem , Adulto , Idoso , Animais , Antineoplásicos Imunológicos/administração & dosagem , Terapia Combinada , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Injeções Intralinfáticas , Interferon-alfa/farmacologia , Linfoma Folicular/imunologia , Linfoma Folicular/patologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Indução de Remissão , Terapia de Salvação , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Recent studies have revealed that type I interferons (IFNs) are powerful inducers of the differentiation and activation of dendritic cells (DCs). These findings emphasize the importance of these cytokines in linking innate and adaptive immunity, suggesting that effects of type I IFN on DCs can play a role in the antitumor and antiviral activity observed in some IFN-treated patients. Thus, the evaluation of the effects of IFN on the differentiation/activation of DCs has become an important approach for testing novel biologically important IFN activities, and the description of some reference methods are urgently needed. In this chapter, we describe some methods for testing the effects of IFNs on the differentiation and activation of human DCs from the peripheral blood monocytes and for the characterization of the DCs generated after IFN treatment.
Assuntos
Diferenciação Celular/fisiologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/fisiologia , Interferon Tipo I/farmacologia , Animais , Antígenos CD/metabolismo , Biomarcadores , Movimento Celular/fisiologia , Células Cultivadas , Meios de Cultura/química , Citocinas/metabolismo , Células Dendríticas/citologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Interferon Tipo I/metabolismo , Camundongos , Camundongos SCID , Monócitos/citologia , Monócitos/fisiologiaRESUMO
Dendritic cells (DCs) are the most potent antigen-presenting cells (APCs) and thus play a pivotal role in induction of the immune response. Recent studies in both human and mouse models have shown that type I IFN, cytokines originally characterized for their antiviral activity and exerting multiple biologic effects, efficiently promote the differentiation and activation of DCs. These observations, together with the findings that DCs can express biologically relevant levels of type I interferon (IFN) and, in particular, that high amounts of these cytokines are released by specialized DC precursors (i.e., plasmacytoid DCs) in response to viral infections, strongly suggest the existence of a natural alliance between type I IFN and DCs, which is instrumental in ensuring an efficient immune response to both infectious agents and tumors. Further recent knowledge on the interactions between type I IFN and DCs emphasizes the importance of these cytokines in linking innate and adaptive immunity and may lead to new perspectives in their use as vaccine adjuvants as well as in strategies for the development of DC-based vaccines.
Assuntos
Células Dendríticas/imunologia , Imunidade , Interferon Tipo I/imunologia , Animais , Diferenciação Celular , Células Dendríticas/citologia , HumanosRESUMO
IFN-α exerts multiple effects leading to immune protection against pathogens and cancer as well to autoimmune reactions by acting on monocytes and dendritic cells. We analyzed the versatility of human monocytes conditioned by IFN-α towards dendritic cell differentiation (IFN-DC) in shaping the autologous T-helper response. Priming of naïve CD4 T cells with autologous IFN-DC in the presence of either SEA or anti-CD3, resulted, in addition to a prominent expansion of CXCR3+ IFN-γ-producing CD4 Th1 cells, in the emergence of two distinct subsets of IL-17-producing CD4 T cells: i) a predominant Th17 population selectively producing IL-17 and expressing CCR6; ii) a minor Th1/Th17 population, producing both IL-17 and IFN-γ. After phagocytosis of apoptotic cells, IFN-DC induced Th17 cell expansion and IL-17 release. Notably, the use of neutralizing antibodies revealed that IL-23 was an essential cytokine in mediating Th17 cell development by IFN-DC. The demonstration of the IFN-DC-induced expansion of both Th1 and Th17 cell populations reveals the intrinsic plasticity of these DC in orienting the immune response and provides a mechanistic link between IFN-α and the onset of autoimmune phenomena, which have been correlated with both IL-17 production and exposure to IFN-α.
Assuntos
Interferon-alfa/farmacologia , Interleucina-12/fisiologia , Interleucina-23/fisiologia , Monócitos/efeitos dos fármacos , Células Th1/fisiologia , Células Th17/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/fisiologia , Diferenciação Celular/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Células Dendríticas/fisiologia , Humanos , Interleucina-12/metabolismo , Interleucina-23/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/fisiologia , Modelos Biológicos , Monócitos/metabolismo , Monócitos/fisiologia , Células Th1/efeitos dos fármacos , Células Th17/metabolismo , Células Th17/fisiologia , Células Th17/transplanteRESUMO
Here we report a novel strategy for the induction of CD8(+) T cell adaptive immune response against viral and tumor antigens. This approach relies on high levels of incorporation in HIV-1 VLPs of a mutant of HIV-1 Nef (Nef(mut)) which can act as anchoring element for foreign proteins. By in vitro assay, we found that VLP-associated Nef(mut) is efficiently cross-presented by antigen presenting cells. Inoculation in mice of VLPs incorporating the HPV-16 E7 protein fused to Nef(mut) led to an anti-E7 CD8(+) T cell response much stronger than that elicited by E7 recombinant protein inoculated with incomplete Freund's adjuvant and correlating with well-detectable anti-E7 CTL activity. Most relevantly, mice immunized with Nef(mut)-E7 VLPs developed a protective immune response against tumors induced by E7 expressing tumor cells. These results make Nef(mut) VLPs a promising candidate for new vaccine strategies focused on the induction of CD8(+) T cell immunity.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Proteínas Oncogênicas Virais/imunologia , Produtos do Gene nef do Vírus da Imunodeficiência Humana/imunologia , Imunidade Adaptativa , Animais , Linhagem Celular , Apresentação Cruzada , HIV-1/imunologia , Papillomavirus Humano 16/imunologia , Humanos , Glicoproteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas E7 de Papillomavirus , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/imunologia , Proteínas Recombinantes de Fusão/imunologia , Vírus da Estomatite Vesicular Indiana/imunologia , Proteínas do Envelope Viral/imunologiaRESUMO
Dendritic cells (DC) generated after a short-term exposure of monocytes to IFN-alpha and GM-CSF (IFN-DC) are highly effective in inducing cross-priming of CD8(+ )T cells against viral antigens. We have investigated the mechanisms responsible for the special attitude of these DC and compared their activity with that of reference DC. Antigen uptake and endosomal processing capabilities were similar for IFN-DC and IL-4-derived DC. Both DC types efficiently cross-presented soluble HCV NS3 protein to the specific CD8(+) T cell clone, even though IFN-DC were superior in cross-presenting low amounts of viral antigens. Moreover, when DC were pulsed with inactivated HIV-1 and injected into hu-PBL-SCID mice, the generation of virus-specific CD8(+ )T cells was markedly higher in animals immunized with IFN-DC than in mice immunized with CD40L-matured IL-4-DC. Of interest, in experiments with purified CD8(+ )T cells, IFN-DC were superior with respect to CD40L-matured IL-4-DC in inducing in vitro cross-priming of HIV-specific CD8(+ )T cells. This property correlated with enhanced potential to express the specific subunits of the IL-23 and IL-27 cytokines. These results suggest that IFN-DC are directly licensed for an efficient CD8(+) T cell priming by mechanisms likely involving enhanced antigen presentation and special attitude to produce IL-12 family cytokines.
Assuntos
Antígenos Virais/imunologia , Linfócitos T CD8-Positivos/imunologia , Apresentação Cruzada/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Interferon-alfa/imunologia , Animais , Formação de Anticorpos/imunologia , Apresentação de Antígeno , Linfócitos T CD4-Positivos/imunologia , Ligante de CD40/imunologia , Diferenciação Celular , Células Cultivadas , Técnicas de Cocultura , Células Dendríticas/citologia , Endossomos/imunologia , HIV-1/imunologia , Humanos , Interferon-alfa/genética , Interleucinas/metabolismo , Camundongos , Fenótipo , Solubilidade , Fatores de TempoRESUMO
Bordetella pertussis toxin B-oligomer (PTX-B) has been shown to inhibit HIV infection and replication in vitro. The potential anti-viral effect of PTX-B was tested here in an in vivo surrogate model of HIV infection, i.e. SCID mice reconstituted with human peripheral blood leukocytes (PBL) (hu-PBL-SCID) and infected with a CCR5-dependent (R5) HIV-1 strain. SCID mice inoculated intra-peritoneal (i.p.) with PTX-B and then infected with the R5 strain SF-162 were sacrificed 7 days later and analyzed for human PBL (hu-PBL) lymphoid tissue reconstitution, infection of hu-PBL, plasma viremia and viral rescue from ex vivo-cultivated i.p. hu-PBL. Unlike mice treated with 500 ng per animal of PTX-B showing no evidence of viral inhibition, daily administration of PTX-B (50 ng per mouse) strongly inhibited virus infection and replication, as determined by undetectable viremia, absence of infected hu-PBL and lack of rescue of infectious HIV in most animals. Furthermore, PTX-B injection 2 h before and twice after infection prevented HIV-1 infection and replication in all (10/10) tested animals. Thus, PTX-B potently inhibited virus infection and replication in hu-PBL-SCID mice, supporting the hypothesis that it may represent a new pharmacological agent against HIV-1 infection.
Assuntos
Fármacos Anti-HIV/farmacologia , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Toxina Pertussis/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Feminino , Humanos , Leucócitos/virologia , Camundongos , Camundongos SCIDRESUMO
The recent advances in immunology and biotechnology have opened new perspectives for the development of immunotherapy strategies against cancer and infectious diseases. The understanding of the pivotal role of dendritic cells in the initiation and regulation of the immune response has led to an ensemble of preclinical studies and pilot clinical trials, which have provided some evidence on the potential advantages of using dendritic cells as cellular adjuvants for the development of therapeutic vaccines against infectious diseases and malignancies. Current research efforts are focused on the definition of optimal protocols for dendritic cell-based therapies in patients. An additional area of emerging importance in the field of immunotherapy is the identification of safe, selective, and more powerful adjuvants, capable not only of enhancing immune protection against pathogens, but also of breaking tolerance against certain tumor-associated antigens, which is the critical issue for the development of cancer vaccines. The recent recognition of the key role of certain cytokines, such as type I interferons, in linking the innate and adaptive immunity through their action on dendritic cells opens new perspectives for using these natural factors as adjuvants for the development of therapeutic vaccines. We review some of the emerging research aspects in immunotherapy, with special attention to the perspectives of using new adjuvants and dendritic cell-based vaccines for the treatment of cancer and infectious diseases.