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1.
Oncoimmunology ; 6(11): e1356964, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29147614

RESUMO

Although promising, the clinical benefit provided by dendritic cell (DC)-based vaccines is still limited and the choice of the optimal antigen formulation is still an unresolved issue. We have developed a new DC-based vaccination protocol for aggressive and/or refractory lymphomas which combines the unique features of interferon-conditioned DC (IFN-DC) with highly immunogenic tumor cell lysates (TCL) obtained from lymphoma cells undergoing immunogenic cell death. We show that treatment of mantle cell lymphoma (MCL) and diffuse large B-cell lymphoma (DLBCL) cell lines with 9-cis-retinoic acid and IFNα (RA/IFNα) induces early membrane exposure of Calreticulin, HSP70 and 90 together with CD47 down-regulation and enhanced HMGB1 secretion. Consistently, RA/IFNα-treated apoptotic cells and -TCLs were more efficiently phagocytosed by DCs compared to controls. Notably, cytotoxic T cells (CTLs) generated with autologous DCs pulsed with RA/IFNα-TCLs more efficiently recognized and specifically lysed MCL or DLBCL cells or targets loaded with several HLA-A*0201 cyclin D1 or HLA-B*0801 survivin epitopes. These cultures also showed an expansion of Th1 and Th17 cells and an increased Th17/Treg ratio. Moreover, DCs loaded with RA/IFNα-TCLs showed enhanced functional maturation and activation. NOD/SCID mice reconstituted with human peripheral blood lymphocytes and vaccinated with autologous RA/IFNα-TCL loaded-IFN-DCs showed lymphoma-specific T-cell responses and a significant decrease in tumor growth with respect to mice treated with IFN-DC unpulsed or loaded with untreated TCLs. This study demonstrates the feasibility and efficacy of the use of RA/IFNα to generate a highly immunogenic TCL as a suitable tumor antigen formulation for the development of effective anticancer DC-based vaccines.

2.
Cell Death Differ ; 21(1): 15-25, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23787994

RESUMO

Conventional anticancer chemotherapy has been historically thought to act through direct killing of tumor cells. This concept stems from the fact that cytotoxic drugs interfere with DNA synthesis and replication. Accumulating evidence, however, indicates that the antitumor activities of chemotherapy also rely on several off-target effects, especially directed to the host immune system, that cooperate for successful tumor eradication. Chemotherapeutic agents stimulate both the innate and adaptive arms of the immune system through several modalities: (i) by promoting specific rearrangements on dying tumor cells, which render them visible to the immune system; (ii) by influencing the homeostasis of the hematopoietic compartment through transient lymphodepletion followed by rebound replenishment of immune cell pools; (iii) by subverting tumor-induced immunosuppressive mechanisms and (iv) by exerting direct or indirect stimulatory effects on immune effectors. Among the indirect ways of immune cell stimulation, some cytotoxic drugs have been shown to induce an immunogenic type of cell death in tumor cells, resulting in the emission of specific signals that trigger phagocytosis of cell debris and promote the maturation of dendritic cells, ultimately resulting in the induction of potent antitumor responses. Here, we provide an extensive overview of the multiple immune-based mechanisms exploited by the most commonly employed cytotoxic drugs, with the final aim of identifying prerequisites for optimal combination with immunotherapy strategies for the development of more effective treatments against cancer.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/terapia , Imunidade Adaptativa , Animais , Antineoplásicos/toxicidade , Morte Celular/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Humanos , Imunoterapia , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Microambiente Tumoral
3.
Clin Exp Immunol ; 155(1): 28-34, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19076826

RESUMO

The capacity of the immunomodulatory drug rapamycin (RAPA) to inhibit replication of the CCR5 strain of human immunodeficiency virus (HIV) in vitro prompted us to test its effects in a murine preclinical model of HIV infection. RAPA (0.6 or 6 mg/kg body weight) or its vehicle were administered daily, per os, to SCID mice reconstituted with human peripheral blood leucocytes (hu-PBL) starting 2 days before the intraperitoneal challenge with the R5 tropic SF162 strain of HIV-1 (1000 50% tissue culture infective dose/ml). Relative to hu-PBL-SCID mice that received no treatment, HIV-infected hu-PBL-SCID mice treated with the vehicle control for 3 weeks exhibited a severe depletion of CD4(+) cells (90%), an increase in CD8(+) cells and an inversion of the CD4(+)/CD8(+) cell ratio. In contrast, treatment of HIV-infected mice with RAPA prevented a decrease in CD4(+) cells and the increase of CD8(+) cells, thereby preserving the original CD4(+):CD8(+) cell ratio. Viral infection also resulted in the detection of HIV-DNA within peritoneal cells and spleen, and lymph node tissues of the vehicle-treated mice within 3 weeks of the viral challenge. In contrast, treatment with RAPA decreased cellular provirus integration and reduced HIV-RNA levels in the blood. Furthermore, in co-cultivation assays, spleens from RAPA-treated mice exhibited a reduced capacity for infecting allogeneic T cells which was dose-dependent. These data show that RAPA possesses powerful anti-viral activity against R5 strains of HIV in vivo and support the use of additional studies to evaluate the potential application of this drug in the management of HIV patients.


Assuntos
Infecções por HIV/tratamento farmacológico , HIV-1 , Imunossupressores/uso terapêutico , Sirolimo/uso terapêutico , Animais , Relação CD4-CD8 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Técnicas de Cocultura , DNA Viral/análise , Humanos , Linfonodos/virologia , Camundongos , Camundongos SCID , Modelos Animais , Peritônio/virologia , RNA Viral/sangue , Baço/virologia
5.
J Leukoc Biol ; 80(6): 1500-11, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16966383

RESUMO

Members of the IFN regulatory factors (IRFs) family are transcriptional regulators that play essential roles in the homeostasis and function of the immune system. Recent studies indicate a direct involvement of some members of the family in the development of different subsets of dendritic cells (DC). Here, we report that IRF-1 is a potent modulator of the development and functional maturation of DC. IRF-1-deficient mice (IRF-1(-/-)) exhibited a predominance of plasmacytoid DC and a selective reduction of conventional DC, especially the CD8alpha(+) subset. IRF-1(-/-) splenic DC were markedly impaired in their ability to produce proinflammatory cytokines such as IL-12. By contrast, they expressed high levels of IL-10, TGF-beta, and the tolerogenic enzyme indoleamine 2,3 dioxygenase. As a consequence, IRF-1(-/-) DC were unable to undergo full maturation and retained plasmacytoid and tolerogenic characteristics following virus infection ex vivo and in vivo. Accordingly, DC from IRF-1(-/-) mice were less efficient in stimulating the proliferation of allogeneic T cells and instead, induced an IL-10-mediated, suppressive activity in allogeneic CD4(+)CD25(+) regulatory T cells. Together, these results indicate that IRF-1 is a key regulator of DC differentiation and maturation, exerting a variety of effects on the functional activation and tolerogenic potential of these cells.


Assuntos
Diferenciação Celular/imunologia , Células Dendríticas/imunologia , Tolerância Imunológica , Fator Regulador 1 de Interferon/deficiência , Fator Regulador 1 de Interferon/imunologia , Plasmócitos/imunologia , Animais , Infecções por Arenaviridae/genética , Infecções por Arenaviridae/imunologia , Infecções por Avulavirus/imunologia , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular/genética , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Citocinas/imunologia , Tolerância Imunológica/genética , Camundongos , Camundongos Knockout , Vírus da Doença de Newcastle/imunologia , Linfócitos T Reguladores/imunologia
7.
Leukemia ; 18(11): 1864-71, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15385939

RESUMO

Interferon regulatory factor (IRF)-1 is a transcription factor controlling the expression of several genes, which are differentially induced depending on the cell type and signal. IRF-1 modulates multiple functions, including regulation of immune responses and host defence, cell growth, cytokine signalling and hematopoietic development. Here, we investigated the role of IRF-1 in granulocytic differentiation in mice with a null mutation in the IRF-1 gene. We show that IRF-1(-/-) bone marrow cells exhibit an increased number of immature granulocytic precursors, associated with a decreased number of mature granulocytic elements as compared to normal mice, suggestive of a defective maturation process. Clonogenetic analyses revealed a reduced number of CFU-G, CFU-M and CFU-GM colonies in IRF-1(-/-) mice, while the number of BFU-E/CFU-E colonies was unchanged. At the molecular level, the expression of CAAT-enhancer-binding protein (C/EBP)-epsilon, -alpha and PU.1 was substantially lower in the CD11b(+) cells from the bone marrow of IRF-1(-/-) mice as compared to cells from wild-type mice. These results, together with the fact that IRF-1 is markedly induced early during granulo-monocytic differentiation of CD34+ cells, highlight the pivotal role of IRF-1 in the early phases of myelopoiesis.


Assuntos
Células da Medula Óssea/citologia , Diferenciação Celular , Proteínas de Ligação a DNA/fisiologia , Granulócitos/citologia , Monócitos/citologia , Mielopoese/fisiologia , Fosfoproteínas/fisiologia , Animais , Células da Medula Óssea/metabolismo , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Antígeno CD11b/metabolismo , Ensaio de Unidades Formadoras de Colônias , Proteínas de Ligação a DNA/genética , Células Precursoras Eritroides , Granulócitos/metabolismo , Homozigoto , Fator Regulador 1 de Interferon , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/metabolismo , Fosfoproteínas/genética , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/metabolismo
8.
Stem Cells ; 21(3): 357-62, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12743330

RESUMO

Dendritic cells (DCs) are a unique leukocyte type consisting of different subsets of professional antigen-presenting cells. Since DCs initiate and govern the immune response, they represent an ideal target for intervention aimed at modulating and potentiating immune responses against cancer and infectious diseases. We recently described and characterized, at a functional level, a novel DC subset, interferon (IFN)-DCs, derived from blood monocytes after a short exposure to type I IFN and GM-CSF. Here, we review our recent studies on IFN-DCs and discuss their possible use in clinical immunotherapeutic strategies.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Imunoterapia/métodos , Interferon Tipo I/farmacologia , Monócitos/efeitos dos fármacos , Diferenciação Celular/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Relação Dose-Resposta a Droga , Humanos , Imunoterapia/tendências , Monócitos/citologia , Monócitos/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia
9.
Blood ; 98(10): 3022-9, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11698286

RESUMO

The migration capability of dendritic cells (DCs) is regulated by their response to factors, namely chemokines, that characterize maturation stage and shape their functional activities. This study examines the morphology, expression of chemokines/chemokine receptors, and migration properties of DCs generated after treatment of monocytes with type I interferon (IFN) and granulocyte-macrophage colony-stimulating factor (GM-CSF) (IFN-DCs). IFN-DCs showed phenotypical and morphologic features undetectable in DCs generated in the presence of interleukin 4 (IL-4) and GM-CSF, such as expression of CD83 and CD25 and the presence of CD44+, highly polarized, thin, and long dendrites. IFN-DCs markedly migrated in response to beta-chemokines (especially MIP-1beta) and expressed the Th-1 chemokine IP-10. Notably, IFN-DCs showed an up-regulation of CCR7 as well as of its natural ligand MIP-3beta, characteristics typical of mature DCs. Of interest, IFN-DCs exhibited a marked chemotactic response to MIP-3beta in vitro and strong migratory behavior in severe combined immunodeficient (SCID) mice. In SCID mice reconstituted with human peripheral blood leukocytes, IFN-DCs induced a potent primary human antibody response and IFN-gamma production, indicative of a Th-1 immune response. These results define the highly specialized maturation state of IFN-DCs and point out the existence of a "natural alliance" between type I IFN and monocyte/DC development, instrumental for ensuring an efficient connection between innate and adaptive immunity.


Assuntos
Quimiocinas CC/biossíntese , Quimiotaxia , Células Dendríticas/efeitos dos fármacos , Linfocinas/biossíntese , Receptores de Quimiocinas/biossíntese , Animais , Anticorpos Heterófilos/biossíntese , Apresentação de Antígeno , Movimento Celular , Extensões da Superfície Celular/ultraestrutura , Quimiocina CCL19 , Quimiocinas CC/genética , Quimiocinas CC/farmacologia , Quimiotaxia/efeitos dos fármacos , Células Dendríticas/metabolismo , Células Dendríticas/transplante , Células Dendríticas/ultraestrutura , Regulação da Expressão Gênica/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Anticorpos Anti-HIV/biossíntese , Proteína gp120 do Envelope de HIV/imunologia , Proteína gp41 do Envelope de HIV/imunologia , HIV-1/imunologia , Humanos , Imunização , Imunofenotipagem , Interferon-alfa/farmacologia , Interferon gama/biossíntese , Interferon gama/genética , Interleucina-4/farmacologia , Linfocinas/genética , Camundongos , Camundongos SCID , Microscopia Eletrônica de Varredura , Monócitos/citologia , Receptores CCR7 , Receptores de Quimiocinas/genética , Fatores de Tempo , Transplante Heterólogo
10.
AIDS ; 15(17): 2231-8, 2001 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-11698695

RESUMO

OBJECTIVE: To develop an animal model of vaginal transmission of HIV-1 for the evaluation of vaginal microbicides. DESIGN: Vaginal infection was performed in SCID mice reconstituted with 4 x 107 human peripheral blood lymphocytes (hu-PBL) by non-invasive vaginal administration. The hu-PBL were previously infected in vitro with a non-syncytium (NSI) strain of HIV-1 (SF162) (hu-PBL-SCID). Lymphocyte migration in vivo was examined using fluorescently labelled human lymphocytes. METHODS: The percentage of CD4 T cells, plasma viral load and p24 antigen were evaluated using fluorescent activated cell sorting (FACS), the Amplicor HIV-1 monitor kit and enzyme-linked immunosorbent assay, respectively. Polymerase chain reaction (PCR) analysis was performed on DNA extracted from spleen and lymph nodes. For in vivo migration of labelled lymphocytes, the mice were sacrificed after 4, 24 and 48 h; vaginae and local lymph nodes were removed, snap frozen with OCT, sectioned and examined by fluorescent microscopy and FACS. RESULTS: HIV transmission was established using virus-infected cells inoculated vaginally, as shown by FACS, HIV viral load, p24 and PCR results. Labelled cells were easily located within the vaginal tissues after 4 h. However, few or no cells could be identified after 24 or 48 h at the vaginal level, whereas labelled cells could be detected at the level of regional lymph nodes. CONCLUSIONS: Because of its simplicity and practical features compared with other animal models, the vaginal HIV-infected hu-SCID mouse model may prove useful to test the activity of compounds against cell-associated HIV and, possibly, other sexually transmitted diseases.


Assuntos
Infecções por HIV/virologia , HIV-1/fisiologia , Vagina/virologia , Animais , Linfócitos T CD4-Positivos/classificação , Linfócitos T CD4-Positivos/citologia , Movimento Celular , DNA Viral/sangue , Modelos Animais de Doenças , Feminino , Corantes Fluorescentes , Produtos do Gene gag/genética , Infecções por HIV/transmissão , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Leucócitos Mononucleares/fisiologia , Camundongos , Camundongos SCID , Provírus/genética , Subpopulações de Linfócitos T
12.
J Virol ; 75(18): 8434-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11507188

RESUMO

The high-yield expression of a neutralizing epitope from human immunodeficiency virus type 1 (HIV-1) on the surface of a plant virus and its immunogenicity are presented. The highly conserved ELDKWA epitope from glycoprotein (gp) 41 was expressed as an N-terminal translational fusion with the potato virus X (PVX) coat protein. The resulting chimeric virus particles (CVPs), purified and used to immunize mice intraperitoneally or intranasally, were able to elicit high levels of HIV-1-specific immunoglobulin G (IgG) and IgA antibodies. Furthermore, the human immune response to CVPs was studied with severe combined immunodeficient mice reconstituted with human peripheral blood lymphocytes (hu-PBL-SCID). hu-PBL-SCID mice immunized with CVP-pulsed autologous dendritic cells were able to mount a specific human primary antibody response against the gp41-derived epitope. Notably, sera from both normal and hu-PBL-SCID mice showed an anti-HIV-1-neutralizing activity. Thus, PVX-based CVPs carrying neutralizing epitopes can offer novel perspectives for the development of effective vaccines against HIV and, more generally, for the design of new vaccination strategies in humans.


Assuntos
Vacinas contra a AIDS/imunologia , Proteínas do Capsídeo , Capsídeo/imunologia , Proteína gp41 do Envelope de HIV/imunologia , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Vacinas Sintéticas/imunologia , Sequência de Aminoácidos , Animais , Capsídeo/genética , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Feminino , Engenharia Genética , Vetores Genéticos , Proteína gp41 do Envelope de HIV/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Dados de Sequência Molecular , Potexvirus/genética , Potexvirus/imunologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Vírion
13.
J Immunol ; 167(3): 1179-87, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11466332

RESUMO

Cytokines that are induced by infection may contribute to the initiation of immune responses through their ability to stimulate dendritic cells (DCs). In this paper, we have addressed the role of IL-15 in DC activation, investigating its expression by DCs in response to three different signals of infection and examining its ability to stimulate DCs. We report that the expression of both IL-15 and the IL-15 receptor alpha-chain are increased in splenic DCs from mice inoculated with dsRNA (poly(I:C)), LPS, or IFN-alphabeta, and in purified murine splenic DCs treated with IFN-alphabeta in vitro. Furthermore, IL-15 itself was able to activate DCs, as in vivo or in vitro exposure of splenic DCs to IL-15 resulted in an up-regulation of costimulatory molecules, markedly increased production of IFN-gamma by DC and an enhanced ability of DCs to stimulate Ag-specific CD8(+) T cell proliferation. The magnitude of all of the IL-15-induced changes in DCs was reduced in mice deficient for the IFN-alphabeta receptor, suggesting a role for IFN-alphabeta in the stimulation of DCs by IL-15. These results identify IL-15 as a stimulatory cytokine for DCs with the potential for autocrine activity and link its effects to expression of IFN-alphabeta.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Interferon Tipo I/administração & dosagem , Interleucina-15/biossíntese , Lipopolissacarídeos/administração & dosagem , RNA de Cadeia Dupla/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Animais , Células Cultivadas , Imunofenotipagem , Injeções Intravenosas , Interferon gama/metabolismo , Interleucina-15/administração & dosagem , Interleucina-15/genética , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Poli I-C/administração & dosagem , RNA Mensageiro/biossíntese , Receptores de Interleucina-15 , Receptores de Interleucina-2/biossíntese , Proteínas Recombinantes/administração & dosagem , Baço/citologia , Baço/imunologia , Linfócitos T/imunologia , Regulação para Cima/genética , Regulação para Cima/imunologia
14.
Immunity ; 14(4): 461-70, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11336691

RESUMO

Type I interferons (IFN-I) are rapidly induced following infection and play a key role in nonspecific inhibition of virus replication. Here we have investigated the effects of IFN-I on the generation of antigen-specific antibody responses. The data show that IFN-I potently enhance the primary antibody response to a soluble protein, stimulating the production of all subclasses of IgG, and induce long-lived antibody production and immunological memory. In addition, endogenous production of IFN-I was shown to be essential for the adjuvant activity of CFA. Finally, IFN-I enhanced the antibody response and induced isotype switching when dendritic cells were the only cell type responding to IFN-I. The data reveal the potent adjuvant activity of IFN-I and their important role in linking innate and adaptive immunity.


Assuntos
Formação de Anticorpos/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Switching de Imunoglobulina/efeitos dos fármacos , Interferon Tipo I/farmacologia , Adjuvantes Imunológicos/farmacologia , Animais , Memória Imunológica , Interferon Tipo I/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Poli I-C/farmacologia , gama-Globulinas/imunologia
15.
J Immunol ; 166(9): 5381-7, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11313374

RESUMO

The present study was designed to evaluate the effect of the HIV-1 envelope glycoprotein gp120 on the expression of beta-chemokines in cultured monocytes/macrophages. Treatment of either freshly isolated 1-day-cultured monocytes or 7-day-cultured monocyte-derived macrophages (MDM) with recombinant gp120-IIIB resulted in a specific and dose-dependent enhancement of secretion of monocyte chemoattractant protein-1, macrophage inflammatory protein-1beta, and RANTES as well as a clear-cut increase in transcript accumulation. The expression of these mRNA was increased, but not superinduced, in the presence of cycloheximide. beta-Chemokine secretion was also induced after exposure of monocyte cultures to gp120-JRFL and aldrithiol-2-inactivated R5 and X4 HIV-1 strains, retaining conformational and functional integrity of envelope proteins. In contrast, no beta-chemokine secretion was triggered by X4 and R5 gp120 or aldrithiol-2-inactivated virus treatment of monocytoid cell lines that were fully responsive to LPS. The gp120-mediated effect was independent of its interaction with CD4, as preincubation with soluble CD4 did not abrogate beta-chemokine induction. Moreover, triggering of CD4 receptor by a specific Ab did not result in any beta-chemokine secretion. Interestingly, engagement of CCR5 and CXCR4 receptors by specific Abs as well as treatment with CCR5 and CXCR4 ligands induced beta-chemokine secretion. On the whole, these results indicate that HIV-1 stimulates monocytes/macrophages to produce beta-chemokines by a specific interaction of gp120 with HIV-1 coreceptors on the cell membrane. The expression of these related polypeptides may represent an important cellular response for regulating both the extent of viral infection and the recruitment of immune cells.


Assuntos
Antígenos CD4/fisiologia , Quimiocinas CC/biossíntese , Proteína gp120 do Envelope de HIV/farmacologia , HIV-1/imunologia , Monócitos/imunologia , Monócitos/virologia , Adolescente , Adulto , Antígenos Virais/farmacologia , Linhagem Celular , Células Cultivadas , Quimiocina CCL2/biossíntese , Quimiocina CCL2/genética , Quimiocina CCL4 , Quimiocina CCL5/biossíntese , Quimiocina CCL5/genética , Quimiocinas CC/sangue , Quimiocinas CC/metabolismo , Humanos , Lipopolissacarídeos/farmacologia , Proteínas Inflamatórias de Macrófagos/biossíntese , Proteínas Inflamatórias de Macrófagos/genética , Masculino , Monócitos/metabolismo , RNA Mensageiro/biossíntese , Receptores de Quimiocinas/fisiologia , Especificidade da Espécie , Transcrição Gênica/imunologia , Células U937 , Regulação para Cima/imunologia
16.
Cancer Gene Ther ; 8(1): 63-72, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11219495

RESUMO

Recent studies have shown that gene therapy with type I interferon (IFN) in an adenovirus vector is a powerful tool to suppress the growth of human tumors transplanted in immune-deficient mice. However, in these studies the host immune-mediated effects, which may be important in mediating the long-term control of tumor growth by these cytokines, was not studied. In this paper, we evaluate the antitumor efficacy of different adenoviral vectors containing mouse IFN-alpha genes (i.e., a first-generation replication-defective vector containing IFN-alpha1 and two different second-generation vectors containing IFN-alpha2) in immunocompetent DBA/2 mice transplanted with highly metastatic Friend leukemic cells resistant in vitro to type I IFN. We found that injection of all the different adenovirus vectors containing mouse IFN-alpha( genes resulted in a marked antitumor response in mice transplanted either subcutaneously or intravenously with IFN-resistant Friend leukemic cells compared to tumor-bearing animals inoculated with a control vector. Tumor growth inhibition after injection of IFN-adenovirus vectors was associated with a prolonged presence of high IFN levels in the sera of the injected mice. Suppression of metastatic tumor growth was also observed after a single injection of the IFN--adenovirus recombinant vectors, whereas a comparable antitumor response generally required several injections of high doses of IFN. Altogether, these results demonstrate that IFN--adenoviral vectors can efficiently inhibit metastatic tumor growth by host-mediated mechanisms and suggest that adenovirus-mediated IFN-alpha gene therapy may represent an attractive alternative to the conventional clinical use of this cytokine, which generally requires multiple injections of high IFN doses for a prolonged period of time.


Assuntos
Adenoviridae/genética , Interferon-alfa/genética , Leucemia Experimental/terapia , Animais , Vírus da Leucemia Murina de Friend , Terapia Genética , Vetores Genéticos , Injeções Intraperitoneais , Injeções Intravenosas , Interferon-alfa/sangue , Interferon-alfa/metabolismo , Óperon Lac/fisiologia , Leucemia Experimental/imunologia , Neoplasias Hepáticas Experimentais/patologia , Neoplasias Hepáticas Experimentais/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos DBA , Camundongos Nus , Metástase Neoplásica , Transplante de Neoplasias , Análise de Sobrevida , Transfecção , Células Tumorais Cultivadas
17.
Eur Cytokine Netw ; 12(4): 597-603, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11781186

RESUMO

We investigated the effect of IFN-beta on beta-chemokine expression in differentiating human peripheral blood monocytes. MCP-1, MIP-1alpha and MIP-1beta were constitutively expressed in 1 day-cultured monocytes, and their secretion increased with time in culture despite any change in mRNA accumulation. IFN-beta treatment of differentiating monocytes resulted in a marked and dose-dependent increase of beta-chemokine secretion, which was regulated differently with respect to the differentiation stage. In particular, IFN-beta upregulated MCP-1 secretion in monocytes at all stages of differentiation although its effect was significantly higher in 1-day cultured monocytes as compared to monocyte-derived macrophages (MDM). In contrast, MIP-1alpha and MIP-1beta secretion was up-regulated by IFN-beta only in MDM. Although MCP-1, MIP-1alpha and MIP-1beta mRNA expression was up-regulated by IFN-beta in both 1 day-cultured monocytes and MDM, no correlation was found between mRNA level and protein secretion. These results suggest that the regulation of beta-chemokine secretion in monocytes/macrophages by IFN-beta occurred through different mechanisms, involving both a direct effect of this cytokine on chemokine gene expression and translational/post-translational steps of regulation more likely linked to the differentiation process. This finding reveals a novel role for this cytokine in the recruitment of specific cell types during the immune response, which may be relevant in the control of viral infections in vivo.


Assuntos
Diferenciação Celular/fisiologia , Quimiocinas CC/biossíntese , Interferon beta/fisiologia , Macrófagos/citologia , Monócitos/metabolismo , Adolescente , Adulto , Quimiocinas CC/genética , Humanos , Técnicas In Vitro , Masculino , RNA Mensageiro/genética
18.
J Leukoc Biol ; 68(5): 707-14, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11073111

RESUMO

We characterized the IL-12 response of mouse macrophages in terms of modulation of IFN-gamma production by cytokines (IFN-alpha and IL-18) and regulation of IL-12 receptor expression. Beta1 and beta2 IL-12R chain mRNA expression increased with time in culture in the absence of exogenous stimulation, with concomitant acquisition of responsiveness to IL-12 for IFN-gamma production. Expression of the IL-12R beta1 chain mRNA was increased further following IL-12 treatment as a consequence of IFN-gamma expression. IL-12 response was regulated differentially by IFN-alpha and IL-18. Neutralization of endogenous type I IFN increased IFN-gamma secretion, whereas exogenous IFN-alpha reduced it. In contrast, IL-18 enhanced IFN-gamma mRNA accumulation and IFN-gamma secretion in IL-12-stimulated, but not -untreated, cultures. The opposite effects exerted by IFN-alpha and IL-18 mirror their mutual capacity of regulating-in a negative or positive manner, respectively-the expression of the IL-12R beta1 chain. We suggest that differential regulation of IL-12 response by IFN-alpha and IL-18 can represent previously unrecognized regulatory mechanisms for maintaining suitable levels of differentiation/activation in macrophages.


Assuntos
Interferon Tipo I/farmacologia , Interferon gama/biossíntese , Interleucina-12/farmacologia , Interleucina-18/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Receptores de Interleucina/biossíntese , Animais , Células Cultivadas , Sinergismo Farmacológico , Inflamação/imunologia , Inflamação/patologia , Interferon Tipo I/biossíntese , Interferon Tipo I/fisiologia , Interleucina-12/antagonistas & inibidores , Macrófagos Peritoneais/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Receptores de Interleucina-12 , Proteínas Recombinantes/farmacologia
19.
Virology ; 277(2): 270-7, 2000 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-11080475

RESUMO

We had previously reported that freshly harvested peritoneal macrophages (PM) are in a type I IFN-mediated antiviral state, which is lost during in vitro culture of PM, concomitantly with a progressive decline in the expression of IFN-beta. We report herein that in vitro culture of PM in the presence of IL-4 or IL-10 results in an enhanced decay of the IFN-beta-mediated antiviral state to vesicular stomatitis virus (VSV). Moreover, IL-4 and IL-10 inhibited the production of type I IFN induced by LPS or NDV infection, as assessed by IFN production and induction of IFN-mediated antiviral state. The accumulation and physiological turnover of IFN-beta mRNA was not affected by IL-4 or IL-10. Finally, neither IL-10 nor IL-4 exerted any inhibitory effect on the antiviral activity induced by exogenous type-I IFN. These results suggest that Th2 cytokines, such as IL-4 and IL-10, act as negative regulators of the type I IFN-mediated antiviral response in PM and may represent stop signals for the constitutive or induced type I IFN expression in PM.


Assuntos
Interferon beta/biossíntese , Interleucina-10/farmacologia , Interleucina-4/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Regulação para Baixo , Interferon beta/genética , Lipopolissacarídeos , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/virologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Vírus da Doença de Newcastle , RNA Mensageiro/genética , Organismos Livres de Patógenos Específicos , Fatores de Tempo , Vírus da Estomatite Vesicular Indiana
20.
J Virol ; 74(21): 10207-11, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11024150

RESUMO

Jurkat T-cell clones, stably expressing the human immunodeficiency virus type 1 (HIV-1) Vpr protein, exhibited an impaired susceptibility to HIV-1 infection. A marked down-modulation of surface CD4 receptors was detected in Vpr-expressing clones with respect to control cells. Likewise, a reduced CD4 expression was also observed in parental Jurkat cells infected with wild-type but not with Vpr-mutant HIV-1. Notably, Vpr-expressing clones were fully susceptible to infection with a vesicular stomatitis virus G protein-pseudotyped HIV-1 virus, indicating that a block at the level of viral entry was responsible for the inhibition of viral replication. The effect exerted by Vpr on HIV replication and CD4 expression suggests that this protein can regulate both the establishment of a productive HIV-1 infection and CD4-mediated T-cell functions.


Assuntos
Antígenos CD4/metabolismo , Produtos do Gene vpr/metabolismo , HIV-1/fisiologia , Regulação para Baixo , Produtos do Gene vpr/genética , HIV-1/genética , Humanos , Células Jurkat , Replicação Viral , Produtos do Gene vpr do Vírus da Imunodeficiência Humana
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