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1.
Int Immunol ; 33(12): 749-754, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34174067

RESUMO

Semaphorins were originally identified as axon-guidance molecules essential for neural development. In addition to their functions in the neural system, members of the semaphorin family have critical functions in many pathophysiological processes, including immune responses, bone homeostasis, cancer and metabolic disorders. In particular, several lines of evidence indicate that mammalian/mechanistic target of rapamycin (mTOR), a central regulator of cell metabolism, regulates the functions of semaphorins in various types of cells, revealing a novel link between semaphorins and cell metabolism. In this review, we discuss recent advances in the immunometabolic functions of semaphorins, with a particular focus on mTOR signaling.


Assuntos
Proteínas do Tecido Nervoso , Semaforinas , Animais , Humanos , Proteínas do Tecido Nervoso/imunologia , Proteínas do Tecido Nervoso/metabolismo , Semaforinas/imunologia , Semaforinas/metabolismo , Transdução de Sinais/imunologia , Sirolimo/imunologia , Sirolimo/metabolismo
2.
Parasit Vectors ; 13(1): 294, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32517744

RESUMO

BACKGROUND: Leishmaniases are a group of neglected tropical parasitic diseases, mainly affecting vulnerable populations of countries with poor socioeconomic status. Development of efficient vaccines is a priority due to the increasing incidence of drug resistance and toxicity to current treatments. In the search for a safe and efficient protective vaccine for human and dog visceral leishmaniases, we analyzed the suitability of the immunomodulatory drug sirolimus (SIR) to boost a preventive DNA vaccine against leishmaniasis. SIR is an already marketed drug that has been described to boost immune protection against different disease models and has also emerged as a promising therapeutic drug against L. major. METHODS: Syrian hamsters were treated with SIR concomitantly with the administration of a DNA vaccine formulation consisting in four plasmids carrying the Leishmania genes LACK, TRYP, PAPLE22 and KMPII, respectively. Two weeks after the last vaccination, the animals were infected intraperitoneally with L. infantum parasites. Five weeks post-infection the parasite load was measured by real-time PCR in target tissues and immune response was evaluated by determining anti-Leishmania specific antibodies in combination with cytokine expression in the spleen. RESULTS: Our results show that the DNA vaccine itself efficiently reduced the burden of parasites in the skin (P = 0.0004) and lymph nodes (P = 0.0452). SIR administration also enhanced the protection by reducing the parasite load in the spleen (P = 0.0004). Vaccinated animals with or without SIR co-treatment showed lower IFN-γ expression levels than those found in the spleen of control animals. mRNA expression levels of NOS2 and IL-10 were found to be significantly higher in the vaccinated plus SIR treated group. CONCLUSIONS: Co-administration of SIR enhances a DNA vaccination regimen against L. infantum, improving the reduction of parasite load in skin, lymph node and spleen. The analysis of immune markers in the spleen after challenge suggests that the trend to recover naïve levels of IFN-γ and IL-10, and the concurrent higher expression of NOS2, may be responsible for the protection induced by our vaccine co-administered with SIR.


Assuntos
Anticorpos Antiprotozoários/sangue , Fatores Imunológicos/administração & dosagem , Leishmaniose Visceral/prevenção & controle , Sirolimo/administração & dosagem , Vacinas de DNA/imunologia , Animais , Cricetinae , Citocinas/imunologia , Imunização , Fatores Imunológicos/imunologia , Leishmania infantum , Leishmaniose Visceral/imunologia , Masculino , Mesocricetus , Carga Parasitária , Plasmídeos/genética , Proteínas de Protozoários/imunologia , Sirolimo/imunologia , Baço/imunologia , Baço/parasitologia , Vacinas de DNA/administração & dosagem
3.
Poult Sci ; 99(1): 416-422, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32416826

RESUMO

This study was conducted to explore the regulatory role of the target of rapamycin complex 1 (TORC1) signaling pathway in crop milk synthesis in breeding pigeons (Columba livia). Three groups of breeding pigeons in the lactation period (n = 30 pairs/group) were respectively injected with rapamycin (RAPA, a specific inhibitor of the target of rapamycin complex) at doses of 0 (vehicle, control), 0.6, or 1.2 mg/kg body weight (BW)/day via the wing vein for 7 days. The average daily feed intake (ADFI) and BW of the breeding pigeons and the BW of young squabs were respectively recorded throughout the experimental period. The breeding pigeons were sacrificed to collect their crop tissues, crop milk, and serum on the eighth day of the experiment. The results showed that neither 0.6 nor 1.2 mg/kg BW RAPA injection affected BW loss or ADFI in breeding pigeons (P > 0.05), while crop thickness and crop relative weight were significantly decreased (P < 0.05) in the 1.2 mg/kg BW rapamycin-injected group. Simultaneously, RAPA (especially at 1.2 mg/kg BW) decreased the crude protein, αs1-casein, αs2-casein, ß-casein, and amino acid contents (Asp, Thr, Ser, Glu, Gly, Ala, Cys, Val, Met, Ile, Leu, Tyr, Lys, His, Arg, and Pro) of crop milk (P < 0.05) and the concentrations of albumin, total protein, and uric acid in the serum of breeding pigeons (P < 0.05). Additionally, the expression of TORC1 pathway-related proteins (TORC1, S6K1, S6, 4EBP1, and eIF4E) was downregulated in the crop tissues of breeding pigeons by 0.6 or 1.2 mg/kg BW/day RAPA injection (P < 0.05). Accordingly, the average daily gain (ADG) of young squabs declined, and the mortality rate increased significantly (P < 0.05). Together, the results showed that RAPA reduced protein and amino acid levels in the crop milk of breeding pigeons and retarded young squab growth, suggesting a crucial role of TORC1 in crop milk synthesis in breeding pigeons.


Assuntos
Proteínas Aviárias/antagonistas & inibidores , Proteínas Aviárias/biossíntese , Columbidae/metabolismo , Papo das Aves/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Animais , Columbidae/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Alvo Mecanístico do Complexo 1 de Rapamicina/biossíntese , Proteínas do Leite/biossíntese , Distribuição Aleatória , Sirolimo/administração & dosagem , Sirolimo/imunologia
4.
Int J Cancer ; 143(11): 3008-3018, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30183073

RESUMO

mTOR pathway inhibitors such as rapalogs represent a promising tool to induce functional memory CD8 T cells. In our study, we investigated the combination of temsirolimus with anticancer vaccines. Using various designs of cancer vaccines (short and long peptides or the B subunit of Shiga toxin as an antigen delivery vector) and tumor models (melanoma, lung and colon cancer), we showed that the administration of temsirolimus efficiently decreased tumor growth and enhanced tumor-specific CD8 T-cell responses induced by vaccination. Furthermore, tumor-specific CD8 T cells induced by the bi-therapy (vaccine + temsirolimus) exhibit phenotypic characteristics of central memory (CD127+ CD62L+ ) CD8 T cells compared to vaccination alone. We demonstrated that regulatory CD4 T cells (Tregs ) expansion in vivo limits the efficacy of the bi-therapy by altering the antitumor CD8 T-cell responses. Finally, the use of a small molecule CCR4 antagonist to prevent Tregs induction considerably improved the efficacy of the bi-therapy by enhancing CD8 T cells-mediated antitumor immunity. Taken together, our study highlights the potential interest of combining cancer vaccines with drugs that promote memory CD8 T cells and inhibit Tregs .


Assuntos
Vacinas Anticâncer/imunologia , Receptores CCR4/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Memória Imunológica/efeitos dos fármacos , Memória Imunológica/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Sirolimo/análogos & derivados , Sirolimo/imunologia , Sirolimo/farmacologia , Vacinação/métodos
5.
Int J Pharm ; 548(2): 759-770, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29038064

RESUMO

Activated endothelial cells play a pivotal role in the pathology of inflammatory disorders and thus present a target for therapeutic intervention by drugs that intervene in inflammatory signaling cascades, such as rapamycin (mammalian target of rapamycin (mTOR) inhibitor). In this study we developed anti-E-selectin immunoliposomes for targeted delivery to E-selectin over-expressing tumor necrosis factor-α (TNF-α) activated endothelial cells. Liposomes composed of 1,2-dipalmitoyl-sn-glycero-3.;hosphocholine (DPPC), Cholesterol, and 1,2-Distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol)-2000]-maleimide (DSPE-PEG-Mal) were loaded with rapamycin via lipid film hydration, after which they were further functionalized by coupling N-succinimidyl-S-acetylthioacetate (SATA)-modified mouse anti human E-selectin antibodies to the distal ends of the maleimidyl (Mal)-PEG groups. In cell binding assays, these immunoliposomes bound specifically to TNF-α activated endothelial cells. Upon internalization, rapamycin loaded immunoliposomes inhibited proliferation and migration of endothelial cells, as well as expression of inflammatory mediators. Our findings demonstrate that rapamycin-loaded immunoliposomes can specifically inhibit inflammatory responses in inflamed endothelial cells.


Assuntos
Antibacterianos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Selectina E/administração & dosagem , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Sirolimo/administração & dosagem , Animais , Antibacterianos/imunologia , Antibacterianos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Selectina E/imunologia , Selectina E/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Lipossomos , Camundongos , Sirolimo/imunologia , Sirolimo/metabolismo
6.
J Control Release ; 261: 223-233, 2017 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-28694031

RESUMO

Allergic contact dermatitis (ACD) is a common T-cell mediated inflammatory skin condition, characterized by an intensely pruritic rash at the site of contact with allergens like poison ivy or nickel. Current clinical treatments use topical corticosteroids, which broadly and transiently suppress inflammation and symptoms of ACD, but fail to address the underlying immune dysfunction. Here, we present an alternative therapeutic approach that teaches the immune system to tolerate contact allergens by expanding populations of naturally suppressive allergen-specific regulatory T cells (Tregs). Specifically, biodegradable poly(ethylene glycol)-poly(lactic-co-glycolic acid) (PEG-PLGA) microparticles were engineered to release TGF-ß1, Rapamycin, and IL-2, to locally sustain a microenvironment that promotes Treg differentiation. By expanding allergen-specific Tregs and reducing pro-inflammatory effector T cells, these microparticles inhibited destructive hypersensitivity responses to subsequent allergen exposure in an allergen-specific manner, effectively preventing or reversing ACD in previously sensitized mice. Ultimately, this approach to in vivo Treg induction could also enable novel therapies for transplant rejection and autoimmune diseases.


Assuntos
Alérgenos/imunologia , Dermatite Alérgica de Contato/terapia , Tolerância Imunológica , Linfócitos T Reguladores/imunologia , Animais , Diferenciação Celular , Dermatite Alérgica de Contato/imunologia , Feminino , Interleucina-2/administração & dosagem , Interleucina-2/imunologia , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Poliésteres/química , Polietilenoglicóis/química , Sirolimo/administração & dosagem , Sirolimo/imunologia , Fator de Crescimento Transformador beta1/administração & dosagem , Fator de Crescimento Transformador beta1/imunologia
7.
Eur J Pharm Biopharm ; 115: 159-167, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28257810

RESUMO

Breast cancer is the second leading cause of cancer deaths among women. Paclitaxel (PTX) is used for its treatment, however non-selectivity, rapid systemic clearance and hypersensitivity to the commercially available formulation are major drawbacks. Rapamycin (RAP), an mTOR inhibitor, acts synergistically with PTX, and thus could be used in combination with it. Drug loading into nanocarriers, particularly liposomes, has proven to enhance efficacy and reduce side-effects of chemotherapeutic drugs. Within this context, the functionalization of liposomes with antibodies for overexpressed receptors on tumor surface is a potential strategy to increase specificity and reduce side-effects. Specifically, active targeting of HER2(+) breast cancer cells can be achieved by immunoliposomes consisting of liposomes coated with an anti-HER2 monoclonal antibody, Trastuzumab. Herein, we have synthesized PTX/RAP co-loaded immunoliposomes coated with Trastuzumab, performed physicochemical characterization, and evaluated the formulations for cytotoxicity and uptake in 4T1 (triple negative) and SKBR3 (HER2 positive) cell lines. Furthermore, we aimed to compare the immunoliposomes with liposomes and solution of PTX/RAP in vivo, employing human xenograft HER2-overexpressing tumors in mouse model. The co-loaded immunoliposomes had a mean particle size of 140.3nm, a zeta potential of -9.85mV and drug encapsulation efficiency of 55.87 and 69.51, respectively for PTX and RAP. The functionalization efficiency of Trastuzumab was higher than 70% and the antibody retained HER2 binding activity. Cell studies showed increased cytotoxicity of PTX/RAP for the immunoliposome, compared to the control liposomes in SKBR3 cells, which could be attributed to enhanced uptake mediated through HER2 binding. Furthermore, immunoliposomes were better able to control tumor growth in vivo, with tumor volume averages corresponding to 25.27, 44.38 and 47.78% of tumor volumes of untreated control, PTX/RAP solution and control liposomes, respectively. Taken together, our results support the clinical development of immunoliposomes for targeted delivery of PTX and RAP to HER2-positive breast cancer.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Neoplasias da Mama/tratamento farmacológico , Lipossomos/administração & dosagem , Paclitaxel/administração & dosagem , Receptor ErbB-2/imunologia , Sirolimo/administração & dosagem , Animais , Neoplasias da Mama/imunologia , Linhagem Celular Tumoral , Feminino , Humanos , Lipossomos/imunologia , Camundongos , Paclitaxel/imunologia , Sirolimo/imunologia , Trastuzumab/administração & dosagem , Trastuzumab/imunologia
8.
Biomaterials ; 105: 167-184, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27522252

RESUMO

Coronary arterial disease (CAD) remains the leading cause of death globally. Percutaneous coronary interventions are frequently used nonsurgical techniques for treating CAD, which may unfortunately lead to arterial restenosis. Currently, there are no effective drugs that can thoroughly prevent restenosis. We hypothesize inflammation-triggerable nanomedicines may function as effective therapeutics for targeted therapy of restenosis, by preferentially releasing their payload at the diseased site. To demonstrate our hypothesis and develop targeted nanotherapies for restenosis, this study was designed to examine effectiveness of nanomedicines responsive to the inflammatory microenvironment with mild acidity and high reactive oxygen species (ROS). To this end, an acetalated ß-cyclodextrin (ß-CD) material (Ac-bCD) was synthesized as a pH-responsive carrier material, while a ROS-responsive material (Ox-bCD) was produced by hydrophobic functionalization of ß-CD with an oxidation-labile group. Based on these two responsive materials, either pH- or ROS-responsive nanoparticles (NPs) were produced by a nanoprecipitation technique and fully characterized. Using rapamycin (RAP) as a candidate drug, responsive nanotherapies were fabricated. In vitro hydrolysis and release studies confirmed these nanovehicles and nanotherapies exhibited desirable responsive behaviors. Both in vitro cell culture and in vivo evaluations revealed their good safety profile. These responsive NPs could be effectively internalized by rat vascular smooth muscle cells, which in turn notably potentiated anti-proliferation and anti-migration activities of RAP. After intravenous (i.v.) injection, NPs may be accumulated at the injured site in the carotid artery of rats subjected to balloon angioplasty injury. Compared with a non-responsive nanotherapy based on poly(lactide-co-glycolide), treatment with either pH- or ROS-responsive nanotherapy by i.v. injection more effectively attenuated neointimal hyperplasia in a rat model of arterial restenosis. Accordingly, nanotherapeutics responsive to the inflammatory microenvironment hold great potential for the management of vascular restenosis by selectively releasing drug molecules at the inflamed sites.


Assuntos
Microambiente Celular/imunologia , Reestenose Coronária/tratamento farmacológico , Reestenose Coronária/imunologia , Nanocápsulas/administração & dosagem , Espécies Reativas de Oxigênio/imunologia , Sirolimo/administração & dosagem , beta-Ciclodextrinas/química , Animais , Arterite/tratamento farmacológico , Arterite/imunologia , Células Cultivadas , Microambiente Celular/efeitos dos fármacos , Imunossupressores/administração & dosagem , Imunossupressores/química , Masculino , Terapia de Alvo Molecular/métodos , Nanocápsulas/química , Ratos , Ratos Sprague-Dawley , Sirolimo/química , Sirolimo/imunologia , Resultado do Tratamento
9.
Nat Nanotechnol ; 11(10): 890-899, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27479756

RESUMO

The development of antidrug antibodies (ADAs) is a common cause for the failure of biotherapeutic treatments and adverse hypersensitivity reactions. Here we demonstrate that poly(lactic-co-glycolic acid) (PLGA) nanoparticles carrying rapamycin, but not free rapamycin, are capable of inducing durable immunological tolerance to co-administered proteins that is characterized by the induction of tolerogenic dendritic cells, an increase in regulatory T cells, a reduction in B cell activation and germinal centre formation, and the inhibition of antigen-specific hypersensitivity reactions. Intravenous co-administration of tolerogenic nanoparticles with pegylated uricase inhibited the formation of ADAs in mice and non-human primates and normalized serum uric acid levels in uricase-deficient mice. Similarly, the subcutaneous co-administration of nanoparticles with adalimumab resulted in the durable inhibition of ADAs, leading to normalized pharmacokinetics of the anti-TNFα antibody and protection against arthritis in TNFα transgenic mice. Adjunct therapy with tolerogenic nanoparticles represents a novel and broadly applicable approach to prevent the formation of ADAs against biologic therapies.


Assuntos
Tolerância Imunológica/efeitos dos fármacos , Nanopartículas/administração & dosagem , Sirolimo/administração & dosagem , Vacinas Sintéticas/imunologia , Adalimumab/administração & dosagem , Adalimumab/imunologia , Anafilaxia , Animais , Artrite Experimental/tratamento farmacológico , Reabsorção Óssea/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Feminino , Hiperuricemia/tratamento farmacológico , Ácido Láctico , Macaca fascicularis , Camundongos Transgênicos , Nanopartículas/efeitos adversos , Nanopartículas/química , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos Sprague-Dawley , Sirolimo/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Vacinas Sintéticas/administração & dosagem
10.
Am J Respir Crit Care Med ; 193(2): 143-53, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26426522

RESUMO

RATIONALE: Corticosteroid resistance is a major barrier to the effective treatment of chronic obstructive pulmonary disease (COPD). Several molecular mechanisms have been proposed, such as activations of the phosphoinositide-3-kinase/Akt pathway and p38 mitogen-activated protein kinase. However, the mechanism for corticosteroid resistance is still not fully elucidated. OBJECTIVES: To investigate the role of mammalian target of rapamycin (mTOR) in corticosteroid sensitivity in COPD. METHODS: The corticosteroid sensitivity of peripheral blood mononuclear cells collected from patients with COPD, smokers, and nonsmoking control subjects, or of human monocytic U937 cells exposed to cigarette smoke extract (CSE), was quantified as the dexamethasone concentration required to achieve 30% inhibition of tumor necrosis factor-α-induced CXCL8 production in the presence or absence of the mTOR inhibitor rapamycin. mTOR activity was determined as the phosphorylation of p70 S6 kinase, using Western blotting. MEASUREMENTS AND MAIN RESULTS: mTOR activity was increased in peripheral blood mononuclear cells from patients with COPD, and treatment with rapamycin inhibited this as well as restoring corticosteroid sensitivity. In U937 cells, CSE stimulated mTOR activity and c-Jun expression, but pretreatment with rapamycin inhibited both and also reversed CSE-induced corticosteroid insensitivity. CONCLUSIONS: mTOR inhibition by rapamycin restores corticosteroid sensitivity via inhibition of c-Jun expression, and thus mTOR is a potential novel therapeutic target for COPD.


Assuntos
Corticosteroides/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-jun/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/efeitos dos fármacos , Corticosteroides/uso terapêutico , Idoso , Resistência a Medicamentos/imunologia , Feminino , Histona Desacetilase 2/efeitos dos fármacos , Histona Desacetilase 2/fisiologia , Humanos , Imunossupressores/imunologia , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/fisiologia , Proteínas Proto-Oncogênicas c-jun/fisiologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Sirolimo/imunologia , Sirolimo/uso terapêutico , Fumar/efeitos adversos , Fumar/fisiopatologia , Serina-Treonina Quinases TOR/fisiologia , Células U937/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia
11.
Am J Med ; 129(6): 568-72, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26714210

RESUMO

The success of organ transplantation allows many transplant recipients to return to life similar to nontransplant patients. Their need for regular health care, including preventive medicine, has switched the majority of responsibilities for their health care from transplant specialists to primary care physicians. To take care of transplant recipients, it is critical for primary care physicians to be familiar with immunosuppressive medications, their side effects, and common complications in transplant recipients. Ten subjects are reviewed here in order to assist primary care physicians in providing optimal care for transplant recipients.


Assuntos
Monitoramento de Medicamentos/normas , Rejeição de Enxerto/tratamento farmacológico , Imunossupressores/uso terapêutico , Transplante de Órgãos/efeitos adversos , Atenção Primária à Saúde/normas , Transplantados , Corticosteroides/efeitos adversos , Corticosteroides/imunologia , Corticosteroides/uso terapêutico , Anticoncepcionais Femininos/administração & dosagem , Anticoncepcionais Femininos/normas , Ciclosporina/efeitos adversos , Ciclosporina/imunologia , Ciclosporina/uso terapêutico , Diarreia/induzido quimicamente , Diarreia/complicações , Diarreia/imunologia , Interações Medicamentosas/imunologia , Monitoramento de Medicamentos/métodos , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Procedimentos Cirúrgicos Eletivos/normas , Feminino , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/imunologia , Masculino , Adesão à Medicação , Ácido Micofenólico/efeitos adversos , Ácido Micofenólico/imunologia , Ácido Micofenólico/uso terapêutico , Osteonecrose/induzido quimicamente , Osteonecrose/tratamento farmacológico , Policitemia/tratamento farmacológico , Policitemia/etiologia , Gravidez , Complicações na Gravidez/induzido quimicamente , Complicações na Gravidez/imunologia , Complicações na Gravidez/prevenção & controle , Atenção Primária à Saúde/métodos , Sirolimo/efeitos adversos , Sirolimo/imunologia , Sirolimo/uso terapêutico , Tacrolimo/efeitos adversos , Tacrolimo/imunologia , Tacrolimo/uso terapêutico , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/etiologia , Infecções Urinárias/imunologia
12.
Cell Immunol ; 301: 74-81, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26687613

RESUMO

The immune response of hemophilia A patients to administered FVIII is a major complication that obviates this very therapy. We have recently described the use of synthetic, biodegradable nanoparticles carrying rapamycin and FVIII peptide antigens, to induce antigen-specific tolerance. Herein we test the tolerogenicity of nanoparticles that contains full length FVIII protein in hemophilia A mice, focusing on anti-FVIII humoral immune response. As expected, recipients of tolerogenic nanoparticles remained unresponsive to FVIII despite multiple challenges for up to 6 months. Furthermore, therapeutic treatments in FVIII-immunized mice with pre-existing anti-FVIII antibodies resulted in diminished antibody titers, albeit efficacy required longer therapy with the tolerogenic nanoparticles. Interestingly, durable FVIII-specific tolerance was also achieved in animals co-administered with FVIII admixed with nanoparticles encapsulating rapamycin alone. These results suggest that nanoparticles carrying rapamycin and FVIII can be employed to induce specific tolerance to prevent and even reverse inhibitor formation.


Assuntos
Fator VIII/administração & dosagem , Hemofilia A/imunologia , Tolerância Imunológica/imunologia , Imunossupressores/administração & dosagem , Nanopartículas , Sirolimo/administração & dosagem , Animais , Anticorpos Neutralizantes/imunologia , Modelos Animais de Doenças , Fator VIII/imunologia , Imunossupressores/imunologia , Camundongos , Sirolimo/imunologia , Vacinas Sintéticas
13.
Cytotherapy ; 17(9): 1188-99, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26276002

RESUMO

BACKGROUND AIMS: Multipotent mesenchymal stromal cells (MSCs) are distinguished by their ability to differentiate into a number of stromal derivatives of interest for regenerative medicine, but they also have immunoregulatory properties that are being tested in a number of clinical settings. METHODS: We show that brief incubations with rapamycin, everolimus, FK506 or cyclosporine A increase the immunosuppressive potency of MSCs and other cell types. RESULTS: The treated MSCs are up to 5-fold more potent at inhibiting the induced proliferation of T lymphocytes in vitro. We show that this effect probably is due to adsorption of the drug by the MSCs during pre-treatment, with subsequent diffusion into co-cultures at concentrations sufficient to inhibit T-cell proliferation. MSCs contain measurable amounts of rapamycin after a 15-min exposure, and the potentiating effect is blocked by a neutralizing antibody to the drug. With the use of a pre-clinical model of acute graft-versus-host disease, we demonstrate that a low dose of rapamycin-treated but not untreated umbilical cord-derived MSCs significantly inhibit the onset of disease. CONCLUSIONS: The use of treated MSCs may achieve clinical end points not reached with untreated MSCs and allow for infusion of fewer cells to reduce costs and minimize potential side effects.


Assuntos
Doença Enxerto-Hospedeiro/prevenção & controle , Tolerância Imunológica/efeitos dos fármacos , Imunossupressores/farmacologia , Transplante de Células-Tronco Mesenquimais/métodos , Sirolimo/farmacologia , Animais , Anticorpos Neutralizantes/imunologia , Proliferação de Células/efeitos dos fármacos , Técnicas de Cocultura , Ciclosporina/farmacologia , Modelos Animais de Doenças , Everolimo/farmacologia , Feminino , Doença Enxerto-Hospedeiro/imunologia , Humanos , Terapia de Imunossupressão/métodos , Ativação Linfocitária/imunologia , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Sirolimo/imunologia , Linfócitos T/imunologia , Tacrolimo/farmacologia , Cordão Umbilical/citologia
14.
J Immunol ; 195(5): 2038-45, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26238486

RESUMO

CD1d-restricted activation of invariant NKT (iNKT) cells results in the abundant production of various types of cytokines and the subsequent modulation of immune responses. This has been shown to be relevant in several clinical disorders, including cancer, autoimmunity, and graft tolerance. Although it is well known that the suppressive function of regulatory T cells is critically dependent on the FOXP3 gene, FOXP3 can also be expressed by conventional human T cells upon activation, indicating the lack of specificity of FOXP3 as a marker for suppressive cells. In this study, we report that the mammalian target of rapamycin (mTOR) inhibitor rapamycin and IL-10, but not TGF-ß, can induce FOXP3 expression in iNKT cell lines. Importantly, however, FOXP3(+) iNKT cells only acquired suppressive abilities when cultured in the presence of the mTOR inhibitor rapamycin. Suppression of responder T cell proliferation by FOXP3(+) iNKT cells was found to be cell contact-dependent and was accompanied by a reduced capacity of iNKT cells to secrete IFN-γ. Notably, imaging flow cytometry analysis demonstrated predominant nuclear localization of FOXP3 in suppressive FOXP3(+) iNKT cells, whereas nonsuppressive FOXP3(+) iNKT cells showed a predominance of cytoplasmically localized FOXP3. In conclusion, whereas IL-10 can enhance FOXP3 expression in iNKT cells, mTOR inhibition is solely required for promoting nuclear localization of FOXP3 and the induction of suppressive FOXP3(+) iNKT cells.


Assuntos
Núcleo Celular/imunologia , Fatores de Transcrição Forkhead/imunologia , Células T Matadoras Naturais/imunologia , Serina-Treonina Quinases TOR/imunologia , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Transporte Ativo do Núcleo Celular/imunologia , Antígeno CTLA-4/imunologia , Antígeno CTLA-4/metabolismo , Linhagem Celular , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Citometria de Fluxo , Fatores de Transcrição Forkhead/metabolismo , Humanos , Imunossupressores/imunologia , Imunossupressores/farmacologia , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-10/imunologia , Interleucina-10/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Monócitos/metabolismo , Células T Matadoras Naturais/metabolismo , Sirolimo/imunologia , Sirolimo/farmacologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo
15.
Cancer Res ; 75(16): 3279-91, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26122844

RESUMO

The metabolic sensor mTOR broadly regulates cell growth and division in cancer cells, leading to a significant focus on studies of rapamycin and its analogues as candidate anticancer drugs. However, mTOR inhibitors have failed to produce useful clinical efficacy, potentially because mTOR is also critical in T cells implicated in immunosurveillance. Indeed, recent studies using rapamycin have demonstrated the important role of mTOR in differentiation and induction of the CD8+ memory in T-cell responses associated with antitumor properties. In this study, we demonstrate that rapamycin harms antitumor immune responses mediated by T cells in the setting of cancer vaccine therapy. Specifically, we analyzed how rapamycin affects the antitumor efficacy of a human papilloma virus E7 peptide vaccine (CyaA-E7) capable of eradicating tumors in the TC-1 mouse model of cervical cancer. In animals vaccinated with CyaA-E7, rapamycin administration completely abolished recruitment of CD8+ T cells into TC-1 tumors along with the ability of the vaccine to reduce infiltration of T regulatory cells and myeloid-derived suppressor cells. Moreover, rapamycin completely abolished vaccine-induced cytotoxic T-cell responses and therapeutic activity. Taken together, our results demonstrate the powerful effects of mTOR inhibition in abolishing T-cell-mediated antitumor immune responses essential for the therapeutic efficacy of cancer vaccines.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Neoplasias/imunologia , Sirolimo/imunologia , Animais , Antibióticos Antineoplásicos/imunologia , Antibióticos Antineoplásicos/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Vacinas Anticâncer/administração & dosagem , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Humanos , Camundongos Endogâmicos C57BL , Células Mieloides/efeitos dos fármacos , Células Mieloides/imunologia , Células Mieloides/metabolismo , Neoplasias/metabolismo , Neoplasias/prevenção & controle , Proteínas E7 de Papillomavirus/imunologia , Sirolimo/farmacologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/imunologia , Serina-Treonina Quinases TOR/metabolismo , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/imunologia
16.
Genes Immun ; 15(6): 413-23, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24898389

RESUMO

The induction of functional memory cytotoxic T lymphocytes (CTLs) is a major goal of vaccination against intracellular pathogens. Interleukin (IL)-12 is critical for the generation of memory CTLs, and inhibition of mammalian target of rapamycin (mTOR) by rapamycin can effectively enhance the memory CTL response. Yet, the role of IL-12 in mTOR's regulation of memory CTL is unknown. Here we hypothesized that the immunostimulatory effects of mTOR on memory CTLs requires IL-12 signaling. Our results revealed that rapamycin increased the generation of memory CTLs in vaccinia virus infection, and this enhancement was dependent upon the IL-12 signal. Furthermore, IL-12 receptor deficiency diminished the secondary expansion of rapamycin-regulated memory and resultant secondary memory CTLs were abolished. Rapamycin enhanced IL-12 signaling by upregulating IL-12 receptor ß2 expression and signal transducer and activator of transcription factor 4 phosphorylation in CTLs during early infection. In addition, rapamycin continually suppressed T-bet expression in both wild-type and IL-12 receptor knockout CTLs. These results indicate an essential role for IL-12 in the regulation of memory CTLs by mTOR and highlight the importance of considering the interplay between cytokines and adjuvants during vaccine design.


Assuntos
Memória Imunológica/imunologia , Interleucina-2/imunologia , Linfócitos T Citotóxicos/imunologia , Serina-Treonina Quinases TOR/imunologia , Vaccinia virus/imunologia , Vacínia/imunologia , Transferência Adotiva , Animais , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Células Cultivadas , Citometria de Fluxo , Interações Hospedeiro-Patógeno/imunologia , Imunossupressores/imunologia , Imunossupressores/farmacologia , Interleucina-2/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptores de Interleucina-12/deficiência , Receptores de Interleucina-12/genética , Receptores de Interleucina-12/imunologia , Fator de Transcrição STAT4/imunologia , Fator de Transcrição STAT4/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Sirolimo/imunologia , Sirolimo/farmacologia , Proteínas com Domínio T/imunologia , Proteínas com Domínio T/metabolismo , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Vacínia/genética , Vacínia/virologia , Vaccinia virus/fisiologia
17.
Clin Immunol ; 153(2): 332-42, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24909732

RESUMO

The golden standard for functional evaluation of immunodeficiencies is the incorporation of [(3)H]-thymidine in a proliferation assay stimulated with mitogens. Recently developed whole blood proliferation assays have the advantage of parallel lymphocyte lineage analysis and in addition provide a non-radioactive alternative. Here we evaluate the Flow-cytometric Assay for Specific Cell-mediated Immune-response in Activated whole blood (FASCIA) in a comparison with [(3)H]-thymidine incorporation in four patients with severe combined immunodeficiency. The threshold for the minimum number of lymphocytes required for reliable responses in FASCIA is determined together with reference values from 100 healthy donors when stimulated with mitogens as well as antigen specific stimuli. Finally, responses against PWM and SEA+SEB stimuli are conducted with clinically relevant immunomodulatory compounds. We conclude that FASCIA is a rapid, stable and sensitive functional whole blood assay that requires small amounts of whole blood that can be used for reliable assessment of lymphocyte reactivity in patients.


Assuntos
Linfócitos B/imunologia , Proliferação de Células , Citometria de Fluxo/métodos , Imunodeficiência Combinada Severa/imunologia , Linfócitos T/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/patologia , Dexametasona/imunologia , Dexametasona/farmacologia , Enterotoxinas/imunologia , Enterotoxinas/farmacologia , Humanos , Imunossupressores/imunologia , Imunossupressores/farmacologia , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-17/imunologia , Interleucina-17/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Mitógenos de Phytolacca americana/imunologia , Mitógenos de Phytolacca americana/farmacologia , Reprodutibilidade dos Testes , Imunodeficiência Combinada Severa/diagnóstico , Sirolimo/imunologia , Sirolimo/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/patologia , Tacrolimo/imunologia , Tacrolimo/farmacologia
18.
Biol Blood Marrow Transplant ; 20(2): 192-201, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24239650

RESUMO

Rapamycin (RAPA) inhibits the mechanistic target of rapamycin (mTOR), a crucial immune system regulator. Dendritic cells (DC) generated in RAPA (RAPA-DC) enrich for CD4(+) forkhead box p3 (FoxP3(+)) regulatory T cells and induce T cell apoptosis by an unknown mechanism. RAPA-DC also promote experimental allograft survival, yet paradoxically secrete increased IL-12, crucial for the generation of IFN-γ(+) CD4(+) T cells. However, IFN-γ is pro-apoptotic and IL-12-driven IFN-γ inhibits experimental graft-versus-host disease (GVHD). We hypothesized that IL-12(hi) RAPA-DC would facilitate IFN-γ-mediated apoptosis of alloreactive T cells and, unlike control (CTR)-DC, would reduce lethal GVHD. Following LPS stimulation, RAPA-DC exhibited decreased MHCII and co-stimulatory molecules and contained a significant population of CD86(lo) IL-12(hi) cells. Consistent with our hypothesis, both unstimulated and LPS-stimulated RAPA-DC enhanced alloreactive CD4(+) T cell apoptosis in culture. Augmented T cell apoptosis was ablated by IFN-γ neutralization or using T cells lacking the IFN-γ receptor, and it was associated with increased expression of Fas and cleaved caspase 8. DC production or responses to IFN-γ were not important to increased apoptotic functions of RAPA-DC. LPS-stimulated IL-12p40(-/-) RAPA-DC induced lower levels of T cell apoptosis in culture, which was further decreased with addition of anti-IFN-γ. Finally, whereas CTR-DC accelerated mortality from GVHD, LPS-treated RAPA-DC significantly prolonged host survival. In conclusion, increased apoptosis of allogeneic CD4(+) T cells induced by LPS-stimulated IL-12(hi) RAPA-DC is mediated in vitro through IFN-γ and in part by increased IL-12 expression. Enhanced production of IL-12, the predominant inducer of IFN-γ by immune cells, is a probable mechanism underlying the capacity of LPS-treated RAPA-DC to reduce GVHD.


Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Apoptose/imunologia , Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Doença Enxerto-Hospedeiro/imunologia , Interleucina-12/imunologia , Sirolimo/uso terapêutico , Animais , Antibióticos Antineoplásicos/imunologia , Diferenciação Celular , Proliferação de Células , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Sirolimo/imunologia
19.
PLoS One ; 8(7): e68183, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23844169

RESUMO

Nicotine is the main tobacco component responsible for tobacco addiction and is used extensively in smoking and smoking cessation therapies. However, little is known about its effects on the immune system. We confirmed that multiple nicotinic receptors are expressed on mouse and human cytotoxic T lymphocytes (CTLs) and demonstrated that nicotinic receptors on mouse CTLs are regulated during activation. Acute nicotine presence during activation increases primary CTL expansion in vitro, but impairs in vivo expansion after transfer and subsequent memory CTL differentiation, which reduces protection against subsequent pathogen challenges. Furthermore, nicotine abolishes the regulatory effect of rapamycin on memory CTL programming, which can be attributed to the fact that rapamycin enhances expression of nicotinic receptors. Interestingly, naïve CTLs from chronic nicotine-treated mice have normal memory programming, which is impaired by nicotine during activation in vitro. In conclusion, simultaneous exposure to nicotine and antigen during CTL activation negatively affects memory development.


Assuntos
Expressão Gênica/imunologia , Memória Imunológica/imunologia , Nicotina/imunologia , Linfócitos T Citotóxicos/imunologia , Transferência Adotiva , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Citometria de Fluxo , Expressão Gênica/efeitos dos fármacos , Humanos , Memória Imunológica/efeitos dos fármacos , Imunossupressores/imunologia , Imunossupressores/farmacologia , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Masculino , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Nicotina/farmacologia , Receptores Nicotínicos/genética , Receptores Nicotínicos/imunologia , Receptores Nicotínicos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sirolimo/imunologia , Sirolimo/farmacologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/metabolismo
20.
Ann N Y Acad Sci ; 1291: 14-32, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23659703

RESUMO

Everolimus is a potent, oral inhibitor of the mammalian target of rapamycin (mTOR) that has been investigated in multiple clinical development programs since 1996. A unique collaboration between academic and pharmaceutical experts fostered research that progressed rapidly, with simultaneous indication findings across numerous tumor types. Initially developed for the prophylaxis of organ transplant rejection, everolimus has demonstrated efficacy and safety for the treatment of patients with various types of cancer (renal cell carcinoma, neuroendocrine tumors of pancreatic origin, and breast cancer) and for adult and pediatric patients with tuberous sclerosis complex. The FDA approval of everolimus for these diseases has addressed several unmet medical needs and is widely accepted by the medical community where treatment options may be limited. An extensive clinical development program is ongoing to establish the role of everolimus as monotherapy, or in combination with other agents, in the treatment of a broad spectrum of malignancies.


Assuntos
Antineoplásicos/administração & dosagem , Imunossupressores/administração & dosagem , Neoplasias/tratamento farmacológico , Sirolimo/análogos & derivados , Serina-Treonina Quinases TOR/antagonistas & inibidores , Administração Oral , Animais , Antineoplásicos/imunologia , Ensaios Clínicos como Assunto/métodos , Everolimo , Humanos , Imunossupressores/química , Neoplasias/imunologia , Sirolimo/administração & dosagem , Sirolimo/imunologia , Serina-Treonina Quinases TOR/imunologia , Esclerose Tuberosa/tratamento farmacológico , Esclerose Tuberosa/imunologia
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