RESUMEN
Multiple sclerosis and experimental autoimmune encephalomyelitis (EAE) are inflammatory diseases of the CNS in which Th17 cells play a major role in the disease pathogenesis. Th17 cells that secrete GM-CSF are pathogenic and drive inflammation of the CNS. IL-9 is a cytokine with pleiotropic functions, and it has been suggested that it controls the pathogenic inflammation mediated by Th17 cells, and IL-9R-/- mice develop more severe EAE compared with wild-type counterparts. However, the underlying mechanism by which IL-9 suppresses EAE has not been clearly defined. In this study, we investigated how IL-9 modulates EAE development. By using mice knockout for IL-9R, we show that more severe EAE in IL-9R-/- mice correlates with increased numbers of GM-CSF+ CD4+ T cells and inflammatory dendritic cells (DCs) in the CNS. Furthermore, DCs from IL-9R-/- mice induced more GM-CSF production by T cells and exacerbated EAE upon adoptive transfer than did wild-type DCs. Our results suggest that IL-9 reduces autoimmune neuroinflammation by suppressing GM-CSF production by CD4+ T cells through the modulation of DCs.
Asunto(s)
Sistema Nervioso Central/fisiología , Células Dendríticas/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Interleucina-9/metabolismo , Esclerosis Múltiple/inmunología , Células Th17/inmunología , Traslado Adoptivo , Animales , Autoinmunidad , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Mediadores de Inflamación/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Interleucina-9/genéticaRESUMEN
Multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) are neuroinflammatory conditions where inflammatory CD4+ T cells play a major role. Forkhead box P3 (Foxp3)+ regulatory T (Treg) cells suppress inflammation and an increase in their numbers and activity is beneficial for MS and EAE. However, studies have shown that Treg cells can transdifferentiate to pathogenic Th17 cells under inflammatory conditions. Drugs that stimulate Treg cell induction and their resistance to inflammatory stimuli are necessary to develop effective therapies to treat MS. Here, we show that primaquine (PQ), an anti-malarial drug, suppresses EAE through the stimulation of Foxp3+ Treg cells. PQ-elicited Treg cells are refractory to inflammatory stimuli and suppress EAE. Additionally, PQ-elicited Foxp3+ Treg cells were more efficient in suppressing the proliferation of responder cells compared to PBS-elicited Treg cells. Although PQ does not directly induce Foxp3+ Treg cell differentiation from naïve T cells, it modulated dendritic cells (DCs) to induce Foxp3+ Treg cells in an indoleamine 2,3 dioxygenase (IDO)-dependent manner. Together, our results show that PQ elicits Foxp3+ Treg cells with a superior suppressive activity to reduce EAE. PQ has the potential as a safe and effective treatment for MS and other CNS autoimmune inflammatory diseases.
Asunto(s)
Factores de Transcripción Forkhead/metabolismo , Primaquina/farmacología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Animales , Antimaláricos/farmacología , Autoinmunidad , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental , Activación de Linfocitos/inmunología , Ratones , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/etiología , Esclerosis Múltiple/metabolismo , Esclerosis Múltiple/patología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Células Th17/efectos de los fármacos , Células Th17/inmunología , Células Th17/metabolismoRESUMEN
MS and EAE are T cell-driven autoimmune diseases of the CNS where IL-17-producing Th17 cells promote damage and are pathogenic. Conversely, tolerogenic DCs induce Treg cells and suppress Th17 cells. Chloroquine (CQ) suppresses EAE through the modulation of DCs by unknown mechanisms. Here, we show that STAT 1 is necessary for CQ-induced tolerogenic DCs (tolDCs) to efficiently suppress EAE. We observed that CQ induces phosphorylation of STAT1 in DCs in vivo and in vitro. Genetic blockage of STAT1 abrogated the suppressive activity of CQ-treated DCs. Opposed to its WT counterparts, CQ-treated STAT1-/- BMDCs were unable to suppress Th17 cells and increased EAE severity. Our findings show that STAT1 is a major signaling pathway in CQ-induced tolDCs and may shed light on new therapeutic avenues for the induction of tolDCs in autoimmune diseases such as MS.
Asunto(s)
Cloroquina/metabolismo , Células Dendríticas/inmunología , Encefalomielitis Autoinmune Experimental/inmunología , Esclerosis Múltiple/inmunología , Neutrófilos/inmunología , Factor de Transcripción STAT1/metabolismo , Células Th17/inmunología , Animales , Autoantígenos/inmunología , Células Cultivadas , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Glicoproteína Mielina-Oligodendrócito/inmunología , Fragmentos de Péptidos/inmunología , Factor de Transcripción STAT1/genética , Transducción de SeñalRESUMEN
BACKGROUND: Unrestrained activation of Th1 and Th17 cells is associated with the pathogenesis of multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis (EAE). While inactivation of dynamin-related protein 1 (Drp1), a GTPase that regulates mitochondrial fission, can reduce EAE severity by protecting myelin from demyelination, its effect on immune responses in EAE has not yet been studied. METHODS: We investigated the effect of Mdivi-1, a small molecule inhibitor of Drp1, on EAE. Clinical scores, inflammation, demyelination and Drp1 activation in the central nervous system (CNS), and T cell responses in both CNS and periphery were determined. RESULTS: Mdivi-1 effectively suppressed EAE severity by reducing demyelination and cellular infiltration in the CNS. Mdivi-1 treatment decreased the phosphorylation of Drp1 (ser616) on CD4+ T cells, reduced the numbers of Th1 and Th17 cells, and increased Foxp3+ regulatory T cells in the CNS. Moreover, Mdivi-1 treatment effectively inhibited IFN-γ+, IL-17+, and GM-CSF+ CD4+ T cells, while it induced CD4+ Foxp3+ regulatory T cells in splenocytes by flow cytometry. CONCLUSIONS: Together, our results demonstrate that Mdivi-1 has therapeutic potential in EAE by modulating the balance between Th1/Th17 and regulatory T cells.
Asunto(s)
Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/patología , Quinazolinonas/farmacología , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Animales , Inhibidores Enzimáticos/farmacología , Femenino , Activación de Linfocitos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Dinámicas Mitocondriales/efectos de los fármacos , Proteínas de Unión al ARN/antagonistas & inhibidores , Linfocitos T Colaboradores-Inductores/inmunologíaRESUMEN
Neuromyelitis optica spectrum disorder is primarily an anti-aquaporin 4 autoantibody-mediated, central nervous system-restricted channelopathy. Patients frequently develop central nervous system-restricted lesions even though autoantigen aquaporin 4 in neuromyelitis optica spectrum disorder is broadly distributed in the central nervous system and peripheral organs. The cause of such tissue-specific immune response remains largely unknown. We confirmed here that CD59, an inhibitory regulator of the complement membrane attack complex, is expressed and co-localized with aquaporin 4 in peripheral organs but is only minimally expressed in astrocytes in the central nervous system. In addition, we further found that CD59 overexpression in mouse brains decreased demyelination, blocked the loss of astrocytes and aquaporin 4, and inhibited membrane attack complex formation and infiltration of inflammatory cells. Inactivation of CD59 in mouse peripheral aquaporin 4-expressing cells and tissues led to complement-dependent cytotoxicity. In accordance with the mouse data, human samples presented higher expression of CD59 in many aquaporin 4-expressing peripheral tissues but not in astrocytes. Silencing or blocking CD59 in aquaporin 4-expressing human tracheal epithelial and skeletal muscle cells induced membrane attack complex formation and cytotoxicity, which suggests a protective role of CD59 in anti-aquaporin 4 antibodies-mediated complement toxicity. Our findings suggest that low CD59 expression in astrocytes may contribute to central nervous system-restricted lesions in neuromyelitis optica spectrum disorder. Restoring CD59 expression in astrocytes may serve as a novel therapeutic target of neuromyelitis optica spectrum disorder.
Asunto(s)
Astrocitos/inmunología , Antígenos CD59/metabolismo , Animales , Acuaporina 4/inmunología , Acuaporina 4/metabolismo , Autoanticuerpos , Autoinmunidad/inmunología , Autoinmunidad/fisiología , Antígenos CD59/genética , Activación de Complemento , Complejo de Ataque a Membrana del Sistema Complemento , Proteínas del Sistema Complemento/inmunología , Femenino , Humanos , Inmunidad Humoral/inmunología , Inmunoglobulina G/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Neuromielitis Óptica/inmunología , Neuromielitis Óptica/metabolismoRESUMEN
BACKGROUND: Paracoccidioidomycosis, a chronic granulomatous fungal disease caused by Paracoccidioides brasiliensis yeast cells affects mainly rural workers, albeit recently cases in immunosuppressed individuals has been reported. Protective immune response against P. brasiliensis is dependent on the activity of helper T cells especially IFN-γ-producing Th1 cells. It has been proposed that Paracoccidioides brasiliensis is able to modulate the immune response towards a permissive state and that the thymus plays a major role in it. METHODS: In this paper, we show that acute infection of BALB/c mice with P. brasiliensis virulent isolate (Pb18) might cause alterations in the thymic environment as well as the prohibitive TCR-expressing T cells in the spleens. RESULTS: After seven days of infection, we found yeast cells on the thymic stroma, the thymic epithelial cells (TEC) were altered regarding their spatial-orientation and inflammatory mediators gene expression was increased. Likewise, thymocytes (differentiating T cells) presented higher migratory ability in ex vivo experiments. Notwithstanding, P. brasiliensis-infected mice showed an increased frequency of prohibitive TCR-expressing T cells in the spleens, suggesting that the selection processes that occur in the thymus may be compromised during the acute infection. CONCLUSION: In this paper, for the first time, we show that acute infection with Paracoccidioides brasiliensis yeast cells promotes thymic alterations leading to a defective repertoire of peripheral T cells. The data presented here may represent new mechanisms by which P. brasiliensis subverts the immune response towards the chronic infection observed in humans.
Asunto(s)
Paracoccidioides/fisiología , Paracoccidioidomicosis/inmunología , Receptores de Antígenos de Linfocitos T/genética , Timo/microbiología , Animales , Humanos , Activación de Linfocitos , Linfocitos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Paracoccidioidomicosis/genética , Paracoccidioidomicosis/microbiología , Receptores de Antígenos de Linfocitos T/inmunología , Bazo/inmunología , Células TH1/inmunología , Timo/inmunologíaRESUMEN
Paracoccidioidomycosis is a systemic infection prevalent in Latin American countries. Disease develops after inhalation of Paracoccidioides brasiliensis conidia followed by an improper immune activation by the host leucocytes. Dendritic cells (DCs) are antigen-presenting cells with the unique ability to direct the adaptive immune response by the time of activation of naive T cells. This study was conducted to test whether extracts of P. brasiliensis would induce maturation of DCs. We found that DCs treated with extracts acquired an inflammatory phenotype and upon adoptive transfer conferred protection to infection. Interestingly, interleukin-10 production by CD8(+) T cells was ablated following DC transfer. Further analyses showed that lymphocytes from infected mice were high producers of interleukin-10, with CD8(+) T cells being the main source. Blockage of cross-presentation to CD8(+) T cells by modulated DCs abolished the protective effect of adoptive transfer. Collectively, our data show that adoptive transfer of P. brasiliensis-modulated DCs is an interesting approach for the control of infection in paracoccidioidomycosis.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Células Dendríticas/inmunología , Interleucina-10/biosíntesis , Paracoccidioides/inmunología , Paracoccidioidomicosis/inmunología , Paracoccidioidomicosis/prevención & control , Traslado Adoptivo , Animales , Antígenos Fúngicos/farmacología , Diferenciación Celular/inmunología , Reactividad Cruzada , Citocinas/biosíntesis , Células Dendríticas/citología , Células Dendríticas/microbiología , Femenino , Vacunas Fúngicas/inmunología , Vacunas Fúngicas/farmacología , Mediadores de Inflamación/metabolismo , Interleucina-10/antagonistas & inhibidores , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones NoqueadosRESUMEN
Dendritic cells (DCs) are professional antigen-presenting cells specifically targeted during Plasmodium infection. Upon infection, DCs show impaired antigen presentation and T-cell activation abilities. In this study, we aimed to evaluate whether cellular extracts obtained from Plasmodium berghei-infected erythrocytes (PbX) modulate DCs phenotypically and functionally and the potential therapeutic usage of PbX-modulated DCs in the control of experimental autoimmune encephalomyelitis (EAE, the mouse model for human multiple sclerosis). We found that PbX-treated DCs have impaired maturation and stimulated the generation of regulatory T cells when cultured with naive T lymphocytes in vitro. When adoptively transferred to C57BL/6 mice the EAE severity was reduced. Disease amelioration correlated with a diminished infiltration of cytokine-producing T cells in the central nervous system as well as the suppression of encephalitogenic T cells. Our study shows that extracts obtained from P. berghei-infected erythrocytes modulate DCs towards an immunosuppressive phenotype. In addition, the adoptive transfer of PbX-modulated DCs was able to ameliorate EAE development through the suppression of specific cellular immune responses towards neuro-antigens. To our knowledge, this is the first study to present evidence that DCs treated with P. berghei extracts are able to control autoimmune neuroinflammation.
Asunto(s)
Traslado Adoptivo , Células Dendríticas/trasplante , Terapia de Inmunosupresión/métodos , Neuritis Autoinmune Experimental/prevención & control , Plasmodium berghei/inmunología , Linfocitos T Reguladores/inmunología , Animales , Células Cultivadas , Técnicas de Cocultivo , Citocinas/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Células Dendríticas/parasitología , Femenino , Inmunidad Celular , Ratones , Ratones Endogámicos C57BL , Neuritis Autoinmune Experimental/inmunología , Neuritis Autoinmune Experimental/metabolismo , Neuritis Autoinmune Experimental/parasitología , Fenotipo , Linfocitos T Reguladores/metabolismo , Linfocitos T Reguladores/parasitología , Factores de TiempoRESUMEN
Chloroquine (CQ), an antimalarial drug, has been shown to modulate the immune system and reduce the severity of experimental autoimmune encephalomyelitis (EAE). The mechanisms of disease suppression are dependent on regulatory T cell induction, although Tregs-independent mechanisms exist. We aimed to evaluate whether CQ is capable to modulate bone marrow-derived dendritic cells (DCs) both phenotypically and functionally as well as whether transfer of CQ-modulated DCs reduces EAE course. Our results show that CQ-treated DCs presented altered ultrastructure morphology and lower expression of molecules involved in antigen presentation. Consequently, T cell proliferation was diminished in coculture experiments. When transferred into EAE mice, DC-CQ was able to reduce the clinical manifestation of the disease through the modulation of the immune response against neuroantigens. The data presented herein indicate that chloroquine-mediated modulation of the immune system is achieved by a direct effect on DCs and that DC-CQ adoptive transfer may be a promising approach for avoiding drug toxicity.
Asunto(s)
Traslado Adoptivo , Presentación de Antígeno/efectos de los fármacos , Antirreumáticos/farmacología , Cloroquina/farmacología , Células Dendríticas , Encefalomielitis Autoinmune Experimental/terapia , Animales , Proliferación Celular/efectos de los fármacos , Células Dendríticas/inmunología , Células Dendríticas/trasplante , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/patología , Femenino , Ratones , Linfocitos T/inmunología , Linfocitos T/patologíaRESUMEN
Dietary proteins play an important role in the regulation of systemic immune response, in a phenomenon known as oral tolerance (OT). To evaluate the effects of OT on a murine model of type II collagen (CII) plus ovalbumin (OVA)-induced arthritis (CIA), mice were fed with OVA either before or after CIA induction. OT significantly reduced the paw edema and synovial inflammation, as well as serum levels of anti-CII, the ex vivo proliferation and inflammatory cytokine production by spleen cells from CIA mice. The frequencies of Foxp3(+) and IL-10(+) cells were higher, whereas IFNγ(+) cells and IL-17(+) cells were lower, among gated CD4(+) spleen T cells from tolerized CIA mice than in those from non-tolerized CIA mice. Adoptive transfer of tolerogenic dendritic cells (DCs) before CIA induction mimics the effects observed in the OT. We demonstrate here that bystander suppression induced by OT can modify the course of CIA and tolerogenic DCs play a role this phenomenon.
Asunto(s)
Artritis Experimental/terapia , Proteínas en la Dieta/uso terapéutico , Tolerancia Inmunológica , Ovalbúmina/uso terapéutico , Traslado Adoptivo , Animales , Artritis Experimental/inmunología , Artritis Experimental/patología , Artritis Experimental/prevención & control , Efecto Espectador , Técnicas de Cocultivo , Colágeno Tipo II/inmunología , Colágeno Tipo II/toxicidad , Citocinas/biosíntesis , Células Dendríticas/inmunología , Células Dendríticas/trasplante , Proteínas en la Dieta/inmunología , Edema/etiología , Factores de Transcripción Forkhead/análisis , Inmunización , Interferón gamma , Interleucina-10 , Interleucina-17 , Isoanticuerpos/sangre , Isoanticuerpos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ovalbúmina/administración & dosificación , Ovalbúmina/inmunología , Ovalbúmina/toxicidad , Organismos Libres de Patógenos Específicos , Bazo/inmunología , Bazo/patologíaRESUMEN
Astrocytes are highly heterogeneous in their phenotype and function, which contributes to CNS disease, repair, and aging; however, the molecular mechanism of their functional states remains largely unknown. Here, we show that activation of sirtuin 1 (SIRT1), a protein deacetylase, played an important role in the detrimental actions of reactive astrocytes, whereas its inactivation conferred these cells with antiinflammatory functions that inhibited the production of proinflammatory mediators by myeloid cells and microglia and promoted the differentiation of oligodendrocyte progenitor cells. Mice with astrocyte-specific Sirt1 knockout (Sirt1-/-) had suppressed progression of experimental autoimmune encephalomyelitis (EAE), an animal model of CNS inflammatory demyelinating disease. Ongoing EAE was also suppressed when Sirt1 expression in astrocytes was diminished by a CRISPR/Cas vector, resulting in reduced demyelination, decreased numbers of T cells, and an increased rate of IL-10-producing macrophages and microglia in the CNS, whereas the peripheral immune response remained unaffected. Mechanistically, Sirt1-/- astrocytes expressed a range of nuclear factor erythroid-derived 2-like 2 (Nfe2l2) target genes, and Nfe2l2 deficiency shifted the beneficial action of Sirt1-/- astrocytes to a detrimental one. These findings identify an approach for switching the functional state of reactive astrocytes that will facilitate the development of astrocyte-targeting therapies for inflammatory neurodegenerative diseases such as multiple sclerosis.
Asunto(s)
Astrocitos , Encefalomielitis Autoinmune Experimental , Sirtuina 1 , Animales , Ratones , Astrocitos/enzimología , Astrocitos/patología , Autoinmunidad , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/patología , Ratones Endogámicos C57BL , Fenotipo , Sirtuina 1/genética , Sirtuina 1/metabolismo , Ratones NoqueadosRESUMEN
BACKGROUND: Multiple sclerosis (MS) is a disease of the central nervous system where an autoimmune response leads to chronic inflammation. It represents the second leading cause of non-traumatic disability in the world, affecting mainly young adults and with high female to male incidence. At present, the causative agent in MS is unknown, preventing the development of prophylaxis policies and the understanding of how the human system copes with this complex inflammation. Tetracyclines (Tet) have attracted great attention due to their anti-inflammatory effects. Minocycline and doxycycline represent the second-generation Tet that have been largely used to treat acne and to suppress inflammation. In addition, they are safer and cheaper than other drugs currently used to treat MS. AIM: This study aims to review recent data involving the Tet minocycline and doxycycline and their therapeutic potential in MS. RELEVANCE FOR PATIENTS: Many of the drugs used to treat MS have severe side effects and are costly. Tet, on the other hand, are a safe and inexpensive class of drugs that can modulate the immune response in MS patients.
RESUMEN
Peptides are molecules that have emerged as crucial candidates for the development of anticancer drugs. Spider venoms are a rich source of peptides (venom peptides - VPs) with biological effects. VPs have been tested as adjuvants in the activation of cells of the immune system with the aim of improving immunotherapies for the treatment of neoplasms. In the present study, the effects of SNX-482, a peptide from the African tarantula Hysterocrates gigas, on macrophages were described. The results showed that the peptide activated M0-macrophages, increasing costimulatory molecules (CD40, CD68, CD80, CD83, CD86) involved in antigen presentation, and also augmenting the checkpoint molecules PD-L1, CTLA-4 and FAS-L; these effects were not concentration-dependent. SNX-482 also increased the release of IL-23 and upregulated the expression of ccr4, ifn-g, gzmb and pdcd1, genes important for the anticancer response. The pretreatment of macrophages with the peptide did not interfere in the modulation of T cells, and macrophages previously polarized to M1 and M2 profile did not respond to SNX-482. These findings represent the expansion of knowledge about the use of VPs in drug discovery, pointing to a potential new candidate for anticancer immunotherapy. Considering that most immunotherapies target the adaptive system, the modulation of macrophages (an innate immune cell) by SNX-482 is especially relevant.
Asunto(s)
Adyuvantes Inmunológicos/farmacología , Activación de Macrófagos/efectos de los fármacos , Venenos de Araña/química , Arañas/química , Animales , Antígenos CD/inmunología , Línea Celular Tumoral , Polaridad Celular , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Expresión Génica , Activación de Macrófagos/inmunología , Ratones , Neoplasias/genética , Neoplasias/inmunología , Venenos de Araña/farmacologíaRESUMEN
Immunomodulation has been considered an important approach in the treatment of malignant tumours. However, the modulation of innate immune cells remains an underexplored tool. Studies from our group demonstrated that the Phoneutria nigriventer spider venom (PnV) administration increased the infiltration of macrophage in glioblastoma, in addition to decreasing the tumour size in a preclinical model. The hypothesis that PnV would be modulating the innate immune system led us to the main objective of the present study: to elucidate the effects of PnV and its purified fractions on cultured macrophages. Results showed that PnV and the three fractions activated macrophages differentiated from bone marrow precursors. Further purification generated 23 subfractions named low weight (LW-1 to LW-12) and high weight (HW-1 to HW-11). LW-9 presented the best immunomodulatory effect. Treated cells were more phagocytic, migrated more, showed an activated morphological profile and induced an increased cytotoxic effect of macrophages on tumour cells. However, while M1-controls (LPS) increased IL-10, TNF-alpha and IL-6 release, PnV, fractions and subfractions did not alter any cytokine, with the exception of LW-9 that stimulated IL-10 production. These findings suggest that molecules present in LW-9 have the potential to be used as immunoadjuvants in the treatment of cancer.
Asunto(s)
Adyuvantes Inmunológicos/farmacología , Glioblastoma/terapia , Inmunoterapia , Macrófagos/efectos de los fármacos , Venenos de Araña/farmacología , Animales , Células Cultivadas , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , RatonesRESUMEN
IFN-ß has been the treatment for multiple sclerosis (MS) for almost three decades, but understanding the mechanisms underlying its beneficial effects remains incomplete. We have shown that MS patients have increased numbers of GM-CSF+ Th cells in circulation, and that IFN-ß therapy reduces their numbers. GM-CSF expression by myelin-specific Th cells is essential for the development of experimental autoimmune encephalomyelitis (EAE), an animal model of MS. These findings suggested that IFN-ß therapy may function via suppression of GM-CSF production by Th cells. In the current study, we elucidated a feedback loop between monocytes and Th cells that amplifies autoimmune neuroinflammation, and found that IFN-ß therapy ameliorates central nervous system (CNS) autoimmunity by inhibiting this proinflammatory loop. IFN-ß suppressed GM-CSF production in Th cells indirectly by acting on monocytes, and IFN-ß signaling in monocytes was required for EAE suppression. IFN-ß increased IL-10 expression by monocytes, and IL-10 was required for the suppressive effects of IFN-ß. IFN-ß treatment suppressed IL-1ß expression by monocytes in the CNS of mice with EAE. GM-CSF from Th cells induced IL-1ß production by monocytes, and, in a positive feedback loop, IL-1ß augmented GM-CSF production by Th cells. In addition to GM-CSF, TNF and FASL expression by Th cells was also necessary for IL-1ß production by monocyte. IFN-ß inhibited GM-CSF, TNF, and FASL expression by Th cells to suppress IL-1ß secretion by monocytes. Overall, our study describes a positive feedback loop involving several Th cell- and monocyte-derived molecules, and IFN-ß actions on monocytes disrupting this proinflammatory loop.
Asunto(s)
Autoinmunidad , Comunicación Celular , Interferón beta/metabolismo , Monocitos/inmunología , Monocitos/metabolismo , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , Animales , Células Presentadoras de Antígenos/inmunología , Células Presentadoras de Antígenos/metabolismo , Autoinmunidad/efectos de los fármacos , Comunicación Celular/genética , Comunicación Celular/inmunología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades/inmunología , Encefalomielitis Autoinmune Experimental/etiología , Encefalomielitis Autoinmune Experimental/metabolismo , Encefalomielitis Autoinmune Experimental/patología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/biosíntesis , Interferón beta/farmacología , Ratones , Ratones Noqueados , Monocitos/efectos de los fármacos , Linfocitos T Colaboradores-Inductores/efectos de los fármacosRESUMEN
OBJECTIVE: To study the immunomodulatory effect of dimethyl fumarate (DF) on granulocyte macrophage colony-stimulating factor (GM-CSF) production in CD4+ T cells in experimental autoimmune encephalomyelitis (EAE) and human peripheral blood mononuclear cells (PBMCs). METHODS: We collected splenocytes and CD4+ T cells from C57BL/6 wild-type and interferon (IFN)-γ-deficient mice. For human PBMCs, venous blood was collected from healthy donors, and PBMCs were collected using the Percoll gradient method. Cells were cultured with anti-CD3/28 in the presence/absence of DF for 3 to 5 days. Cells were stained and analyzed by flow cytometry. Cytokines were measured by ELISA in cell supernatants. For in vivo experiments, EAE was induced by myelin oligodendrocyte glycoprotein35-55 and mice were treated with oral DF or vehicle daily. RESULTS: DF acts directly on CD4+ T cells and suppresses GM-CSF-producing Th1 not Th17 or single GM-CSF+ T cells in EAE. In addition, GM-CSF suppression depends on the IFN-γ pathway. We also show that DF specifically suppresses Th1 and GM-CSF-producing Th1 cells in PBMCs from healthy donors. CONCLUSIONS: We suggest that DF exclusively suppresses GM-CSF-producing Th1 cells in both animal and human CD4+ T cells through an IFN-γ-dependent pathway. These findings indicate that DF has a better therapeutic effect on patients with Th1-dominant immunophenotype. However, future longitudinal study to validate this finding in MS is needed.
Asunto(s)
Linfocitos T CD4-Positivos/efectos de los fármacos , Dimetilfumarato/farmacología , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Granulocitos/efectos de los fármacos , Factores Inmunológicos/farmacología , Interferón gamma/metabolismo , Factor Estimulante de Colonias de Macrófagos/efectos de los fármacos , Células TH1/efectos de los fármacos , Adulto , Animales , Dimetilfumarato/administración & dosificación , Femenino , Humanos , Factores Inmunológicos/administración & dosificación , Interferón gamma/deficiencia , Ratones , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacosRESUMEN
Studies that show an overview of the peripheral immune response in a model of Paracoccidioides brasiliensis (Pb) infection in females are scarce in the literature. We sought to characterize the innate and adaptive immune responses in female C57BL/6 mice infected with Pb through two distinct routes of administration, intranasal and intravenous. In addition to the lung, P. brasiliensis yeast cells were observed in liver and brain tissues of females infected intravenously. To our knowledge, our study is the first to prove the presence of this pathogenic fungus in the cerebral cortex of female mice. During the initial stages of infection, augmented expression of both MHCII and CD86 was observed on the surface of CD11c+ pulmonary antigen-presenting cells (APCs) in intranasally and intravenously infected females. However, CD40 expression was downregulated in these cells. Concomitantly with increasing serum IL-10 levels, we noted that splenic dendritic cells (DCs) from both intravenously- and intranasally-infected female mice had acquired an immature phenotype. Further, increased T regulatory cell counts were observed in female mice infected via both routes, along with an increase in the infiltration of IL-10-producing CD8+ T cells into the lungs. Moreover, we noted that P. brasiliensis infection resulted in enhanced IL-10 production - by CD11c+ APCs in the lung tissue - and induction of Th17 polarization. Taken together, our results suggest that P. brasiliensis could modulates the immune response in female mice by influencing the balance between regulatory T cells (Tregs) and Th17 polarization.
Asunto(s)
Interacciones Huésped-Patógeno , Recuento de Linfocitos , Paracoccidioides/inmunología , Paracoccidioidomicosis/inmunología , Paracoccidioidomicosis/microbiología , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Animales , Citocinas/metabolismo , Femenino , Interacciones Huésped-Patógeno/inmunología , Mediadores de Inflamación/metabolismo , Ratones , Paracoccidioidomicosis/transmisión , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismoRESUMEN
Multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) are neuroinflammatory diseases of the central nervous system (CNS), where leukocytes and CNS resident cells play important roles in disease development and pathogenesis. The antimalarial drug chloroquine (CQ) has been shown to suppress EAE by modulating dendritic cells (DCs) and Th17 cells. However, the mechanism of action by which CQ modulates EAE is far from being elucidated. Here, we comprehensively analyzed the CNS of CQ and PBS-treated EAE mice to identify and characterize the cells that are affected by CQ. Our results show that leukocytes are largely modulated by CQ and have a reduction in the expression of inflammatory markers. Intriguingly, CQ vastly modulated the CNS resident cells astrocytes, oligodendrocytes (OLs) and microglia (MG), with the latter producing IL-10 and IL-12p70. Overall, our results show a panoramic view of the cellular components that are affect by CQ and provide further evidence that drug repurposing of CQ will be beneficial to MS patients.
RESUMEN
Molecules from animal venoms are promising candidates for the development of new drugs. Previous in vitro studies have shown that the venom of the spider Phoneutria nigriventer (PnV) is a potential source of antineoplastic components with activity in glioblastoma (GB) cell lines. In the present work, the effects of PnV on tumor development were established in vivo using a xenogeneic model. Human GB (NG97, the most responsive line in the previous study) cells were inoculated (s.c.) on the back of RAG-/- mice. PnV (100 µg/Kg) was administrated every 48 h (i.p.) for 14 days and several endpoints were evaluated: tumor growth and metabolism (by microPET/CT, using 18F-FDG), tumor weight and volume, histopathology, blood analysis, percentage and profile of macrophages, neutrophils and NK cells isolated from the spleen (by flow cytometry) and the presence of macrophages (Iba-1 positive) within/surrounding the tumor. The effect of venom was also evaluated on macrophages in vitro. Tumors from PnV-treated animals were smaller and did not uptake detectable amounts of 18F-FDG, compared to control (untreated). PnV-tumor was necrotic, lacking the histopathological characteristics typical of GB. Since in classic chemotherapies it is observed a decrease in immune response, methotrexate (MTX) was used only to compare the PnV effects on innate immune cells with a highly immunosuppressive antineoplastic drug. The venom increased monocytes, neutrophils and NK cells, and this effect was the opposite of that observed in the animals treated with MTX. PnV increased the number of macrophages in the tumor, while did not increase in the spleen, suggesting that PnV-activated macrophages were led preferentially to the tumor. Macrophages were activated in vitro by the venom, becoming more phagocytic; these results confirm that this cell is a target of PnV components. Spleen and in vitro PnV-activated macrophages were different of M1, since they did not produce pro- and anti-inflammatory cytokines. Studies in progress are selecting the venom molecules with antitumor and immunomodulatory effects and trying to better understand their mechanisms. The identification, optimization and synthesis of antineoplastic drugs from PnV molecules may lead to a new multitarget chemotherapy. Glioblastoma is associated with high morbidity and mortality; therefore, research to develop new treatments has great social relevance. Natural products and their derivatives represent over one-third of all new molecular entities approved by FDA. However, arthropod venoms are underexploited, although they are a rich source of new molecules. A recent in vitro screening of the Phoneutria nigriventer spider venom (PnV) antitumor effects by our group has shown that the venom significantly affected glioblastoma cell lines. Therefore, it would be relevant to establish the effects of PnV on tumor development in vivo, considering the complex neoplastic microenvironment. The venom was effective at impairing tumor development in murine xenogeneic model, activating the innate immune response and increasing tumor infiltrating macrophages. In addition, PnV activated macrophages in vitro for a different profile of M1. These activated PnV-macrophages have potential to fight the tumor without promoting tumorigenesis. Studies in progress are selecting the venom molecules with antitumor and immunomodulatory effects and trying to better understand their mechanisms. We aim to synthesize and carry out a formulation with these antineoplastic molecules for clinical trials. Spider venom biomolecules induced smaller and necrotic xenogeneic GB; spider venom activated the innate immune system; venom increased blood monocytes and the migration of macrophages to the tumor; activated PnV-macrophages have a profile different of M1 and have a potential to fight the tumor without promote tumorigenesis.
Asunto(s)
Antineoplásicos/uso terapéutico , Glioblastoma/tratamiento farmacológico , Venenos de Araña/uso terapéutico , Animales , Línea Celular Tumoral , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Glioblastoma/inmunología , Humanos , Inmunidad/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Trasplante de Neoplasias , Arañas , Microtomografía por Rayos XRESUMEN
Matrine (MAT), a quinolizidine alkaloid component derived from the root of Sophora flavescens, suppresses experimental autoimmune encephalomyelitis (EAE), the animal model of multiple sclerosis (MS), by inducing the production of immunomodulatory molecules, e.g., IL-10. In an effort to find the upstream pathway(s) of the mechanism underlying these effects, we have tested certain upregulated immunomodulatory molecules. Among them, we found increased levels of IL-27 and IFN-ß, one of the first-line MS therapies. Indeed, while low levels of IFN-ß production in sera and type I interferon receptor (IFNAR1) expression in spinal cord of saline-treated control EAE mice were detected, they were significantly increased after MAT treatment. Increased numbers of CD11b+IFN-ß+ microglia/infiltrating macrophages were observed in the CNS of MAT-treated mice. The key role of IFN-ß induction in the suppressive effect of MAT on EAE was further verified by administration of anti-IFN-ß neutralizing antibody, which largely reversed the therapeutic effect of MAT. Further, we found that, while MAT treatment induced production of IL-27 and IL-10 by CNS microglia/macrophages, this effect was significantly reduced by IFN-ß neutralizing antibody. Finally, the role of IFN-ß in MAT-induced IL-27 and IL-10 production was further confirmed in human monocytes in vitro. Together, our study demonstrates that MAT exerts its therapeutic effect in EAE through an IFN-ß/IL-27/IL-10 pathway, and is likely a novel, safe, low-cost, and effective therapy as an alternative to exogenous IFN-ß for MS.