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1.
J Immunol ; 200(7): 2313-2326, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29440353

RESUMEN

A balance between Th17 cells and regulatory T cells (Tregs) is important for host immunity and immune tolerance. The underlying molecular mechanisms remain poorly understood. Here we have identified Cdc42 as a central regulator of Th17/Treg balance. Deletion of Cdc42 in T cells enhanced Th17 differentiation but diminished induced Treg differentiation and suppressive function. Treg-specific deletion of Cdc42 decreased natural Tregs but increased effector T cells including Th17 cells. Notably, Cdc42-deficient Th17 cells became pathogenic associated with enhanced glycolysis and Cdc42-deficient Tregs became unstable associated with weakened glycolytic signaling. Inhibition of glycolysis in Cdc42-deficient Th17 cells diminished their pathogenicity and restoration of glycolysis in Cdc42-deficient Tregs rescued their instability. Intriguingly, Cdc42 deficiency in T cells led to exacerbated wasting disease in mouse models of colitis and Treg-specific deletion of Cdc42 caused early, fatal lymphoproliferative diseases. In summary, we show that Cdc42 is a bona fide regulator of peripheral tolerance through suppression of Th17 aberrant differentiation/pathogenicity and promotion of Treg differentiation/stability/function involving metabolic signaling and thus Cdc42 pathway might be harnessed in autoimmune disease therapy.


Asunto(s)
Glucólisis/genética , Tolerancia Inmunológica/inmunología , Linfocitos T Reguladores/inmunología , Células Th17/inmunología , Proteína de Unión al GTP cdc42/metabolismo , Animales , Diferenciación Celular/inmunología , Proliferación Celular/genética , Colitis/genética , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Recuento de Linfocitos , Trastornos Linfoproliferativos/genética , Ratones , Ratones Noqueados , Transducción de Señal/genética , Transducción de Señal/inmunología , Proteína de Unión al GTP cdc42/genética
2.
Clin Exp Allergy ; 49(1): 92-107, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30307073

RESUMEN

BACKGROUND: Asthma is an allergic airway inflammation-driven disease that affects more than 300 million people world-wide. Targeted therapies for asthma are largely lacking. Although asthma symptoms can be prevented from worsening, asthma development cannot be prevented. Cdc42 GTPase has been shown to regulate actin cytoskeleton, cell proliferation and survival. OBJECTIVES: To investigate the role and targeting of Cdc42 in Th2 cell differentiation and Th2-mediated allergic airway inflammation. METHODS: Post-thymic Cdc42-deficient mice were generated by crossing Cdc42flox/flox mice with dLckicre transgenic mice in which Cre expression is driven by distal Lck promoter. Effects of post-thymic Cdc42 deletion and pharmacological targeting Cdc42 on Th2 cell differentiation were evaluated in vitro under Th2-polarized culture conditions. Effects of post-thymic Cdc42 deletion and pharmacological targeting Cdc42 on allergic airway inflammation were evaluated in ovalbumin- and/or house dust mite-induced mouse models of asthma. RESULTS: Post-thymic deletion of Cdc42 led to reduced peripheral CD8+ T cells and attenuated Th2 cell differentiation, with no effect on closely related Th1, Th17 and induced regulatory T (iTreg) cells. Post-thymic Cdc42 deficiency ameliorated allergic airway inflammation. The selective inhibition of Th2 cell differentiation by post-thymic deletion of Cdc42 was recapitulated by pharmacological targeting of Cdc42 with CASIN, a Cdc42 activity-specific chemical inhibitor. CASIN also alleviated allergic airway inflammation. CASIN-treated Cdc42-deficient mice showed comparable allergic airway inflammation to vehicle-treated Cdc42-deficient mice, indicative of negligible off-target effect of CASIN. CASIN had no effect on established allergic airway inflammation. CONCLUSION AND CLINICAL RELEVANCE: Cdc42 is required for Th2 cell differentiation and allergic airway inflammation, and rational targeting Cdc42 may serve as a preventive but not therapeutic approach for asthma control.


Asunto(s)
Asma , Diferenciación Celular , Células Th2/inmunología , Proteína de Unión al GTP cdc42 , Animales , Asma/genética , Asma/inmunología , Asma/patología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Eliminación de Gen , Ratones , Ratones Transgénicos , Células Th2/patología , Proteína de Unión al GTP cdc42/genética , Proteína de Unión al GTP cdc42/inmunología
3.
Biochim Biophys Acta Mol Basis Dis ; 1864(3): 934-941, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29305916

RESUMEN

Asthma is a chronic airway inflammation in which Th2 and Th17 cells play critical roles in its pathogenesis. We have reported that atypical protein kinase (PKC) λ/ι is a new regulator for Th2 differentiation and function. However, the role of PKCλ/ι for Th17 cells remains elusive. In this study, we explored the effect of PKCλ/ι on Th17 cells in the context of ex vivo cell culture systems and an in vivo murine model of allergic airway inflammation with the use of activated T cell-specific conditional PKCλ/ι-deficient mice. Our findings indicate that PKCλ/ι regulates Th17 cells. The secretion of Th17 effector cytokines, including IL-17, IL-21 and IL-22, were inhibited from PKCλ/ι-deficient T cells under non-skewing or Th17-skewing culture conditions. Moreover, the impaired Th17 differentiation and function by the PKCλ/ι-deficiency was associated with the downregulation of Stat3 and Rorγt, key Th17 transcription factors. We developed a model of Th17 and neutrophil-involved allergic airway inflammation by intratracheal inoculation of house dust mites. PKCλ/ι-deficiency significantly inhibited airway inflammations. The infiltrating cells in the lungs and bronchoalveolar lavage fluids were significantly reduced in conditional PKCλ/ι-deficient mice. Th17 effector cytokines were reduced in the bronchoalveolar lavage fluids and lungs at protein and mRNA levels. Thus, PKCλ/ι emerges as a critical regulator of Th17 differentiation and allergic airway hyperresponsiveness.


Asunto(s)
Diferenciación Celular/genética , Inflamación , Isoenzimas/fisiología , Proteína Quinasa C/fisiología , Pyroglyphidae/inmunología , Hipersensibilidad Respiratoria , Células Th17/fisiología , Animales , Dermatophagoides pteronyssinus/inmunología , Embrión de Mamíferos , Femenino , Inflamación/genética , Inflamación/inmunología , Isoenzimas/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Embarazo , Proteína Quinasa C/genética , Hipersensibilidad Respiratoria/genética , Hipersensibilidad Respiratoria/inmunología
4.
J Allergy Clin Immunol ; 137(1): 231-245.e4, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26100081

RESUMEN

BACKGROUND: Mitochondrial metabolism is known to be important for T-cell activation. However, its involvement in effector T-cell differentiation has just begun to gain attention. Importantly, how metabolic pathways are integrated with T-cell activation and effector cell differentiation and function remains largely unknown. OBJECTIVE: We sought to test our hypothesis that RhoA GTPase orchestrates glycolysis for TH2 cell differentiation and TH2-mediated allergic airway inflammation. METHODS: Conditional RhoA-deficient mice were generated by crossing RhoA(flox/flox) mice with CD2-Cre transgenic mice. Effects of RhoA on TH2 differentiation were evaluated based on in vitro TH2-polarized culture conditions and in vivo in ovalbumin-induced allergic airway inflammation. Cytokine levels were measured by using intracellular staining and ELISA. T-cell metabolism was measured by using the Seahorse XF24 Analyzer and flow cytometry. RESULTS: Disruption of RhoA inhibited T-cell activation and TH2 differentiation in vitro and prevented the development of allergic airway inflammation in vivo, with no effect on TH1 cells. RhoA deficiency in activated T cells led to multiple defects in metabolic pathways, such as glycolysis and oxidative phosphorylation. Importantly, RhoA couples glycolysis to TH2 cell differentiation and allergic airway inflammation through regulating IL-4 receptor mRNA expression and TH2-specific signaling events. Finally, inhibition of Rho-associated protein kinase, an immediate downstream effector of RhoA, blocked TH2 differentiation and allergic airway inflammation. CONCLUSION: RhoA is a key component of the signaling cascades leading to TH2 differentiation and allergic airway inflammation at least in part through control of T-cell metabolism and the Rho-associated protein kinase pathway.


Asunto(s)
Glucólisis , Hipersensibilidad Respiratoria/metabolismo , Células Th2/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Alérgenos/inmunología , Animales , Diferenciación Celular , Inflamación/inmunología , Inflamación/metabolismo , Ratones Noqueados , Ratones Transgénicos , Ovalbúmina/inmunología , Hipersensibilidad Respiratoria/inmunología , Células Th2/citología , Células Th2/inmunología , Proteína de Unión al GTP rhoA/deficiencia , Proteína de Unión al GTP rhoA/genética , Proteína de Unión al GTP rhoA/inmunología
5.
J Immunol ; 193(12): 5973-82, 2014 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25398325

RESUMEN

Thymocyte development is regulated by complex signaling pathways. How these signaling cascades are coordinated remains elusive. RhoA of the Rho family small GTPases plays an important role in actin cytoskeleton organization, cell adhesion, migration, proliferation, and survival. Nonetheless, the physiological function of RhoA in thymocyte development is not clear. By characterizing a conditional gene targeting mouse model bearing T cell deletion of RhoA, we show that RhoA critically regulates thymocyte development by coordinating multiple developmental events. RhoA gene disruption caused a strong developmental block at the pre-TCR checkpoint and during positive selection. Ablation of RhoA led to reduced DNA synthesis in CD4(-)CD8(-), CD4(+)CD8(-), and CD4(-)CD8(+) thymocytes but not in CD4(+)CD8(+) thymocytes. Instead, RhoA-deficient CD4(+)CD8(+) thymocytes showed an impaired mitosis. Furthermore, we found that abrogation of RhoA led to an increased apoptosis in all thymocyte subpopulations. Importantly, we show that the increased apoptosis was resulted from reduced pre-TCR expression and increased production of reactive oxygen species (ROS), which may be because of an enhanced mitochondrial function, as manifested by increased oxidative phosphorylation, glycolysis, mitochondrial membrane potential, and mitochondrial biogenesis in RhoA-deficient thymocytes. Restoration of pre-TCR expression or treatment of RhoA-deficient mice with a ROS scavenger N-acetylcysteine partially restored thymocyte development. These results suggest that RhoA is required for thymocyte development and indicate, to our knowledge, for the first time that fine-tuning of ROS production by RhoA, through a delicate control of metabolic circuit, may contribute to thymopoiesis.


Asunto(s)
Marcación de Gen , Mitocondrias/genética , Mitocondrias/metabolismo , Timocitos/citología , Timocitos/metabolismo , Proteína de Unión al GTP rhoA/genética , Animales , Antígenos de Superficie , Apoptosis/genética , Apoptosis/inmunología , Diferenciación Celular , Linaje de la Célula/genética , Linaje de la Célula/inmunología , Supervivencia Celular/genética , Perfilación de la Expresión Génica , Inmunofenotipificación , Ratones , Ratones Noqueados , Fenotipo , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/metabolismo , Recombinación V(D)J , Proteína de Unión al GTP rhoA/deficiencia
6.
EMBO J ; 29(19): 3421-33, 2010 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-20808283

RESUMEN

Allergic airway inflammation is a disease in which T helper 2 (Th2) cells have a critical function. The molecular mechanisms controlling Th2 differentiation and function are of paramount importance in biology and immunology. Recently, a network of PB1-containing adapters and kinases has been shown to be essential in this process owing to its function in regulating cell polarity and the activation of critical transcription factors. Here, we show in vivo data showing that T-cell-specific NBR1-deficient mice show impaired lung inflammation and have defective Th2 differentiation ex vivo with alterations in T-cell polarity and the selective inhibition of Gata3 and nuclear factor of activated T c1 activation. These results establish NBR1 as a novel PB1 adapter in Th2 differentiation and asthma.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Diferenciación Celular/inmunología , Proteínas/metabolismo , Hipersensibilidad Respiratoria/inmunología , Transducción de Señal/fisiología , Células Th2/inmunología , Proteínas Adaptadoras Transductoras de Señales/inmunología , Compuestos de Alumbre/toxicidad , Animales , Western Blotting , Polaridad Celular/inmunología , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Factor de Transcripción GATA3/antagonistas & inhibidores , Humanos , Inmunoprecipitación , Péptidos y Proteínas de Señalización Intracelular , Células Jurkat , Ratones , Ratones Noqueados , Factores de Transcripción NFATC/metabolismo , Ovalbúmina/toxicidad , Reacción en Cadena de la Polimerasa , Proteínas/genética , Proteínas/inmunología , Hipersensibilidad Respiratoria/inducido químicamente , Hipersensibilidad Respiratoria/genética , Células Th2/fisiología
7.
Haematologica ; 98(9): 1353-8, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23716557

RESUMEN

mTOR integrates signals from nutrients and growth factors to control protein synthesis, cell growth, and survival. Although mTOR has been established as a therapeutic target in hematologic malignancies, its physiological role in regulating hematopoiesis remains unclear. Here we show that conditional gene targeting of mTOR causes bone marrow failure and defects in multi-lineage hematopoiesis including myelopoiesis, erythropoiesis, thrombopoiesis, and lymphopoiesis. mTOR deficiency results in loss of quiescence of hematopoietic stem cells, leading to a transient increase but long-term exhaustion and defective engraftment of hematopoietic stem cells in lethally irradiated recipient mice. Furthermore, ablation of mTOR causes increased apoptosis in lineage-committed blood cells but not hematopoietic stem cells, indicating a differentiation stage-specific function. These results demonstrate that mTOR is essential for hematopoietic stem cell engraftment and multi-lineage hematopoiesis.


Asunto(s)
Marcación de Gen/métodos , Hematopoyesis/fisiología , Trasplante de Células Madre Hematopoyéticas/métodos , Serina-Treonina Quinasas TOR/fisiología , Animales , Supervivencia Celular/fisiología , Células Cultivadas , Ratones , Ratones Noqueados , Ratones SCID
8.
J Immunol ; 186(3): 1512-20, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21209282

RESUMEN

Autoantibody production is a hallmark of autoimmune diseases, such as lupus and rheumatoid arthritis. Accumulating evidence suggests a role of invariant NKT (iNKT) cells in their pathogenesis. Mechanisms underlying the role of iNKT cells in these diseases, however, remain unclear. In this study, we show that iNKT cells suppress IgG anti-DNA Ab and rheumatoid factor production and reduce IL-10-secreting B cells in a contact-dependent manner, but increase total IgG production and enhance activation markers on B cells via soluble factors. In vivo reconstitution with iNKT cells also reduces autoantibody production in iNKT-deficient mice and in SCID mice implanted with B cells. Using an anti-DNA transgenic model, we found that autoreactive B cells spontaneously produce IL-10 and are activated in vivo. In the presence of activated iNKT cells, these autoreactive B cells are selectively reduced, whereas nonautoreactive B cells are markedly activated. Because iNKTs recognize CD1d, we reasoned that CD1d might play a role in the differential regulation of autoreactive versus nonautoreactive B cells by iNKT cells. Indeed, autoreactive B cells express more CD1d than nonautoreactive B cells, and CD1d deficiency in lupus mice exacerbates autoantibody production and enhances Ab response to a self-peptide but not to a foreign peptide. Importantly, iNKT cells fail to inhibit autoantibody production by CD1d-deficient B cells. Thus, iNKT cells inhibit autoreactive B cells in a contact- and CD1d-dependent manner but activate nonautoreactive B cells via cytokines. Such ability of iNKTs to suppress autoantibody production, without causing global suppression of B cells, has important implications for the development of iNKT-based therapy for autoimmune diseases.


Asunto(s)
Antígenos CD1d/fisiología , Autoanticuerpos/metabolismo , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Adhesión Celular/inmunología , Células T Asesinas Naturales/inmunología , Animales , Antígenos CD1d/genética , Antígenos CD1d/metabolismo , Autoanticuerpos/biosíntesis , Adhesión Celular/genética , Galactosilceramidas/farmacología , Inmunoglobulina G/metabolismo , Inmunosupresores/farmacología , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Depleción Linfocítica , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NZB , Ratones Noqueados , Ratones SCID , Ratones Transgénicos , Células T Asesinas Naturales/metabolismo
9.
Cell Rep ; 42(4): 112364, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-37043352

RESUMEN

The clinical response to immune checkpoint blockade (ICB) correlates with tumor-infiltrating cytolytic T lymphocytes (CTLs) prior to treatment. However, many of these inflamed tumors resist ICB through unknown mechanisms. We show that tumors with transcription elongation deficiencies (TEdef+), which we previously reported as being resistant to ICB in mouse models and the clinic, have high baseline CTLs. We show that high baseline CTLs in TEdef+ tumors result from aberrant activation of the nucleic acid sensing-TBK1-CCL5/CXCL9 signaling cascade, which results in an immunosuppressive microenvironment with elevated regulatory T cells and exhausted CTLs. ICB therapy of TEdef+ tumors fail to increase CTL infiltration and suppress tumor growth in both experimental and clinical settings, suggesting that TEdef+, along with surrogate markers of tumor immunogenicity such as tumor mutational burden and CTLs, should be considered in the decision process for patient immunotherapy indication.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico , Neoplasias , Animales , Ratones , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Neoplasias/patología , Inmunoterapia/métodos , Transducción de Señal , Inflamación/tratamiento farmacológico , Microambiente Tumoral
10.
J Clin Immunol ; 32(1): 106-13, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22002593

RESUMEN

CD1d presents glycolipid antigens such as α-galactosylceramide (αGalCer) to invariant natural killer T cells (iNKT). We have reported that activated iNKTs inhibit IL-10-producing autoreactive B cells, while promoting or leaving intact the normal B cell responses, making iNKT modulation an attractive therapeutic modality. Here, we report that a brief treatment of young lupus-prone (NZB/NZW)F1 (BWF1) mice with two injections of αGalCer conferred a long-term protection against lupus. Long-term repeated administrations of αGalCer, however, afforded no clinical benefit. These disparate clinical effects correlated with iNKT responsiveness. While a brief treatment with αGalCer enhanced iNKT responses upon in vitro recall, the long-term αGalCer treatment resulted in reduced iNKT responses in BWF1 mice. The improvement in disease with αGalCer treatment was associated with the reduced IL-10 production. Furthermore, iNKTs directly inhibited IL-10-secreting cells in vivo in reconstituted SCID mice and inhibited IL-10-secreting B cells in vitro in co-cultures. Thus, a brief treatment with a CD1d-binding glycolipid enhances iNKT responses, reduces IL-10 production, and delays the onset of lupus, whereas long-term repeated treatments induce marked iNKT hyporesponsiveness and do not affect disease outcome in BWF1 mice. Identifying glycolipid regimens that can modulate iNKT responsiveness will have important implications for developing iNKT-based therapies for autoimmune diseases.


Asunto(s)
Galactosilceramidas/uso terapéutico , Nefritis Lúpica/prevención & control , Células T Asesinas Naturales/inmunología , Animales , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Galactosilceramidas/administración & dosificación , Interleucina-10/biosíntesis , Ligandos , Nefritis Lúpica/tratamiento farmacológico , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NZB , Ratones Noqueados , Ratones SCID , Proteinuria/metabolismo
11.
Proc Natl Acad Sci U S A ; 106(4): 1099-104, 2009 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-19144923

RESUMEN

The differentiation of T cells along different lineages is central to the control of immunity. Here we have used a conditional gene knockout system to delete PKC lambda/iota selectively in activated T cells. With this system we have demonstrated that PKC lambda/iota is necessary for T-helper cell (Th2) cytokine production and optimal T-cell proliferation and allergic airway inflammation in vivo. Our data demonstrate that the activation of the transcription factors nuclear factor of activated T cells and NF-kappaB is impaired in PKC lambda/iota-deficient activated T cells. In addition, we present genetic knockout evidence in ex vivo experiments with primary T cells that PKC lambda/iota is critical for the control of cell polarity during T-cell activation. Therefore PKC lambda/iota emerges as a critical regulator of Th 2 activation.


Asunto(s)
Hipersensibilidad/enzimología , Hipersensibilidad/inmunología , Inflamación/enzimología , Isoenzimas/deficiencia , Proteína Quinasa C/deficiencia , Sistema Respiratorio/patología , Células Th2/enzimología , Células Th2/inmunología , Animales , Diferenciación Celular , Polaridad Celular , Proliferación Celular , Citocinas/metabolismo , Inmunoglobulina E/sangre , Inflamación/inmunología , Isoenzimas/metabolismo , Activación de Linfocitos , Ratones , Ratones Noqueados , Ovalbúmina , Proteína Quinasa C/metabolismo , Sistema Respiratorio/enzimología , Sistema Respiratorio/inmunología , Células Th2/citología , Células Th2/metabolismo , Factores de Transcripción/metabolismo , Regulación hacia Arriba
12.
J Immunother Cancer ; 10(11)2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36427906

RESUMEN

BACKGROUND: Cancer immunotherapy has taken center stage in cancer treatment. However, the current immunotherapies only benefit a small proportion of patients with cancer, necessitating better understanding of the mechanisms of tumor immune evasion and improved cancer immunotherapy strategies. Regulatory T (Treg) cells play an important role in maintaining immune tolerance through inhibiting effector T-cell function. In the tumor microenvironment, Treg cells are used by tumor cells to counteract effector T cell-mediated tumor suppression. Targeting Treg cells may thus unleash the antitumor activity of effector T cells. While systemic depletion of Treg cells can cause excessive effector T-cell responses and subsequent autoimmune diseases, controlled targeting of Treg cells may benefit patients with cancer. METHODS: Treg cells from Treg cell-specific heterozygous Cdc42 knockout mice, C57BL/6 mice treated with a Cdc42 inhibitor CASIN, and control mice were examined for their homeostasis and stability by flow cytometry. The autoimmune responses in Treg cell-specific heterozygous Cdc42 knockout mice, CASIN-treated C57BL/6 mice, and control mice were assessed by H&E staining and ELISA. Antitumor T-cell immunity in Treg cell-specific heterozygous Cdc42 knockout mice, CASIN-treated C57BL/6 mice, humanized NSGS mice, and control mice was assessed by challenging the mice with MC38 mouse colon cancer cells, KPC mouse pancreatic cancer cells, or HCT116 human colon cancer cells. RESULTS: Treg cell-specific heterozygous deletion or pharmacological targeting of Cdc42 with CASIN does not affect Treg cell numbers but induces Treg cell instability, leading to antitumor T-cell immunity without detectable autoimmune reactions. Cdc42 targeting causes an additive effect on immune checkpoint inhibitor anti-programmed cell death protein-1 antibody-induced T-cell response against mouse and human tumors. Mechanistically, Cdc42 targeting induces Treg cell instability and unleashes antitumor T-cell immunity through carbonic anhydrase I-mediated pH changes. CONCLUSIONS: Rational targeting of Cdc42 in Treg cells holds therapeutic promises in cancer immunotherapy.


Asunto(s)
Neoplasias del Colon , Linfocitos T Reguladores , Humanos , Ratones , Animales , Ratones Endogámicos C57BL , Inmunoterapia , Ratones Noqueados , Microambiente Tumoral
13.
Front Immunol ; 12: 726393, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34721389

RESUMEN

RhoA of the Rho GTPase family is prenylated at its C-terminus. Prenylation of RhoA has been shown to control T helper 17 (Th17) cell-mediated colitis. By characterizing T cell-specific RhoA conditional knockout mice, we have recently shown that RhoA is required for Th2 and Th17 cell differentiation and Th2/Th17 cell-mediated allergic airway inflammation. It remains unclear whether RhoA plays a cell-intrinsic role in regulatory T (Treg) cells that suppress effector T cells such as Th2/Th17 cells to maintain immune tolerance and to promote tumor immune evasion. Here we have generated Treg cell-specific RhoA-deficient mice. We found that homozygous RhoA deletion in Treg cells led to early, fatal systemic inflammatory disorders. The autoimmune responses came from an increase in activated CD4+ and CD8+ T cells and in effector T cells including Th17, Th1 and Th2 cells. The immune activation was due to impaired Treg cell homeostasis and increased Treg cell plasticity. Interestingly, heterozygous RhoA deletion in Treg cells did not affect Treg cell homeostasis nor cause systemic autoimmunity but induced Treg cell plasticity and an increase in effector T cells. Importantly, heterozygous RhoA deletion significantly inhibited tumor growth, which was associated with tumor-infiltrating Treg cell plasticity and increased tumor-infiltrating effector T cells. Collectively, our findings suggest that graded RhoA expression in Treg cells distinguishes tumor immunity from autoimmunity and that rational targeting of RhoA in Treg cells may trigger anti-tumor T cell immunity without causing autoimmune responses.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Neoplasias/inmunología , Linfocitos T Reguladores/inmunología , Proteína de Unión al GTP rhoA/deficiencia , Animales , Autoinmunidad , Línea Celular Tumoral , Femenino , Tolerancia Inmunológica/inmunología , Ratones , Linfocitos T Reguladores/patología , Células Th17/inmunología , Células Th17/patología , Células Th2/inmunología , Células Th2/patología , Escape del Tumor , Proteína de Unión al GTP rhoA/inmunología
14.
J Leukoc Biol ; 106(5): 1139-1151, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31260596

RESUMEN

Asthma is a heterogeneous chronic airway inflammation in which Th2 and Th17 cells are key players in its pathogenesis. We have reported that RhoA of Rho GTPases orchestrated glycolysis for Th2 cell differentiation and allergic airway inflammation by the use of a conditional RhoA-deficient mouse line. However, the role of RhoA in Th17 cells remains to be elucidated. In this study, we investigated the effects of RhoA deficiency on Th17 cells in the context of ex vivo cell culture systems and an in vivo house dust mites (HDM)-induced allergic airway inflammation. We found that RhoA deficiency inhibited Th17 differentiation and effector cytokine secretion, which was associated with the downregulations of Stat3 and Rorγt, key Th17 transcription factors. Furthermore, loss of RhoA markedly suppressed Th17 and neutrophil-involved airway inflammation induced by HDM in mice. The infiltrating inflammatory cells in the lungs and bronchoalveolar lavage (BAL) fluids were dramatically reduced in conditional RhoA-deficient mice. Th17 as well as Th2 effector cytokines were suppressed in the airways at both protein and mRNA levels. Interestingly, Y16, a specific RhoA inhibitor, was able to recapitulate the most phenotypes of RhoA genetic deletion in Th17 differentiation and allergic airway inflammation. Our data demonstrate that RhoA is a key regulator of Th17 cell differentiation and function. RhoA might serve as a potential novel therapeutic target for asthma and other inflammatory disorders.


Asunto(s)
Asma/inmunología , Diferenciación Celular/inmunología , Pyroglyphidae/inmunología , Células Th17/inmunología , Proteína de Unión al GTP rhoA/deficiencia , Animales , Asma/inducido químicamente , Asma/genética , Asma/patología , Diferenciación Celular/genética , Ratones , Ratones Noqueados , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/inmunología , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/inmunología , Células Th17/patología , Células Th2/inmunología , Células Th2/patología , Proteína de Unión al GTP rhoA/inmunología
15.
Exp Ther Med ; 17(5): 3859-3866, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30988771

RESUMEN

Ginsenoside Rb1 (GRb1) is a major ingredient of ginseng, a traditional medicine that has been used for thousands of years. Previous studies have reported that GRb1 had anti-inflammatory, antioxidant and neuroprotective effects. The current study aimed to evaluate the antinociceptive effects of GRb1 in a rat model of cancer-induced bone pain (CIBP) established by intratibial injection of Walker 256 cells. Intraperitoneal injection (i.p.) of GRb1 (5 and 10 mg/kg, but not 1 mg/kg) partially and transiently reversed the mechanical allodynia and thermal hyperalgesia in CIBP rats at 14 days following surgery when the pain behavior is established. Furthermore, repeated administration of GRb1 demonstrated persistent analgesic effect. Additionally, the protein expression and immunoreactivity of iba1, which is the maker of microglia, was significantly suppressed in CIBP rats treated with GRb1 (i.p., 10 mg/kg) from day 12 for three consecutive days compared with CIBP rats treated with a vehicle. Furthermore, upregulation of spinal interleukin (IL)-1ß, IL-6 and tumor necrosis factor-α were also significantly inhibited by the treatment of GRb1 (i.p., 10 mg/kg) from day 12 for three consecutive days. Together, these results indicated that GRb1 may attenuate CIBP via inhibiting the activation of microglia and glial-derived proinflammatory cytokines.

16.
Cells ; 8(10)2019 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-31623153

RESUMEN

BACKGROUND: Schistosomiasis is an immunopathogenic disease in which Th17 cells play vital roles. Hepatic granuloma formation and subsequent fibrosis are its main pathologic manifestations and the leading causes of hepatic cirrhosis, and effective therapeutic interventions are lacking. In this study, we explored the effects of fasudil, a selective RhoA-Rho-associated kinase (ROCK) inhibitor, on Th17 cells and the pathogenesis of schistosomiasis. METHODS: Mice were infected with Schistosoma japonicum and treated with fasudil. The worm burden, hepatic granuloma formation, and fibrosis were evaluated. The roles of fasudil on Th17, Treg, and hepatic stellate cells were analyzed. RESULTS: Fasudil therapy markedly reduced the granuloma size and collagen deposit in livers from mice infected with S. japonicum. However, fasudil therapy did not affect the worm burden in infected mice. The underlying cellular and molecular mechanisms were investigated. Fasudil suppressed the activation and induced the apoptosis of CD4+ T cells. Fasudil inhibited the differentiation and effector cytokine secretion of Th17 cells, whereas it upregulated Treg cells in vitro. It also restrained the in vivo interleukin (IL)-4 and IL-17 levels in infected mice. Fasudil directly induced the apoptosis of hepatic stellate cells and downregulated the expressions of hepatic fibrogenic genes, such as collagen type I (Col-I), Col-III, and transforming growth factor-1 (TGF-ß1). These effects may contribute to its anti-pathogenic roles in schistosomiasis. CONCLUSIONS: Fasudil inhibits hepatic granuloma formation and fibrosis with downregulation of Th17 cells. Fasudil might serve as a novel therapeutic agent for hepatic fibrosis due to schistosome infections and perhaps other disorders.


Asunto(s)
1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/metabolismo , Inhibidores de Proteínas Quinasas/uso terapéutico , Schistosoma japonicum/patogenicidad , Células Th17/efectos de los fármacos , Células Th17/metabolismo , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/uso terapéutico , Animales , Diferenciación Celular/efectos de los fármacos , Colágeno Tipo I/metabolismo , Femenino , Citometría de Flujo , Granuloma/tratamiento farmacológico , Granuloma/metabolismo , Interferón gamma/metabolismo , Interleucina-17/metabolismo , Interleucina-4/metabolismo , Ratones , Ratones Endogámicos C57BL , Reacción en Cadena en Tiempo Real de la Polimerasa , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Proteína de Unión al GTP rhoA/antagonistas & inhibidores , Proteína de Unión al GTP rhoA/metabolismo
17.
PLoS One ; 13(1): e0190996, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29304132

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0179565.].

18.
PLoS One ; 12(8): e0183266, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28813526

RESUMEN

The mammalian target of rapamycin (mTOR), present in mTOR complex 1 (mTORC1) and mTORC2, is a serine/threonine kinase that integrates nutrients, growth factors, and cellular energy status to control protein synthesis, cell growth, survival and metabolism. However, it remains elusive whether mTOR plays a developmental stage-specific role in tissue development and whether mTOR can function independent of its complexes and kinase activity. In this study, by inducible genetic manipulation approach, we investigated the role of mTOR and its dependence on mTOR complexes and kinase activity in mitochondrial fitness of early, progenitor stage (lineage-negative; Lin-) versus later, lineage-committed stage (lineage-positive; Lin+) of hematopoietic cells. We found that oxidative phosphorylation (OXPHOS), ATP production and mitochondrial DNA synthesis were decreased in mTOR-/- Lin- cells but increased in mTOR-/- Lin+ cells, suggesting that mTOR plays a developmental stage-specific role in OXPHOS, ATP production and mitochondrial DNA synthesis. In contrast to mTOR deletion, simultaneous deletion of Raptor, a key component of mTORC1, and Rictor, a key component of mTORC2, led to increased mitochondrial DNA in Lin- cells and decreased mitochondrial DNA and ATP production in Lin+ cells, suggesting that mTOR regulates mitochondrial DNA synthesis in Lin- and Lin+ cells and ATP production in Lin+ cells independent of mTORC1 and mTORC2. Similar to mTOR deletion, deletion of Raptor alone attenuated glycolysis and increased mitochondrial mass and mitochondrial membrane potential in Lin- cells and increased mitochondrial mass and OXPHOS in Lin+ cells, whereas deletion of Rictor alone had no effect on these mitochondrial parameters in Lin- and Lin+ cells, suggesting that mTOR regulates glycolysis and mitochondrial membrane potential in Lin- cells, OXPHOS in Lin+ cells, and mitochondrial mass in both Lin- and Lin+ cells dependent on mTORC1, but not mTORC2. Either Raptor deficiency or Rictor deficiency recapitulated mTOR deletion in decreasing OXPHOS in Lin- cells and glycolysis in Lin+ cells, suggesting that mTOR regulates OXPHOS in Lin- cells and glycolysis in Lin+ cells dependent on both mTORC1 and mTORC2. Finally, mice harboring a mTOR kinase dead D2338A knock-in mutant showed decreased glycolysis in Lin+ cells, as seen in mTOR-/- Lin+ cells, but no change in glycolysis in Lin- cells, in contrast to the decreased glycolysis in mTOR-/- Lin- cells, suggesting that mTOR regulates glycolysis in Lin+ cells dependent on its kinase activity, whereas mTOR regulates glycolysis in Lin- cells independent of its kinase activity.


Asunto(s)
Complejos Multiproteicos/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Adenosina Trifosfato/metabolismo , Animales , ADN Mitocondrial/genética , Glucólisis/genética , Glucólisis/fisiología , Immunoblotting , Diana Mecanicista del Complejo 1 de la Rapamicina , Diana Mecanicista del Complejo 2 de la Rapamicina , Potencial de la Membrana Mitocondrial/fisiología , Ratones , Ratones Mutantes , Complejos Multiproteicos/genética , Fosforilación Oxidativa , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/genética , Transducción de Señal/fisiología , Serina-Treonina Quinasas TOR/genética
19.
PLoS One ; 12(6): e0179565, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28614408

RESUMEN

The "hygiene hypothesis" is a theory try to explain the dramatic increases in the prevalence of autoimmune and allergic diseases over the past two to three decades in developed countries. According to this theory, reduced exposure to parasites and microorganisms in childhood is the main cause for the increased incidences of both T helper 1 (Th1)-mediated autoimmunity and Th2-mediated allergy. In this study, we investigated the impact of Schistosoma japonicum infection on the allergic airway inflammation induced by repeated intracheal inoculations of house dust mites (HDM), which is a Th17 and neutrophils dominant murine asthma model, mimicking severe asthma. We found that S. japonicum infection downregulated airway hyperresponsiveness. The infiltrating cells, Th17 and Th2 effector cytokines in the bronchoalveolar lavage (BAL) fluids and lungs were significantly reduced in the infected mice. Our findings indicated that S. japonicum infection was able to effectively inhibit host's allergic airway inflammation, which may be related to the upregulated Treg cells upon infection. To our knowledge, it is the first study to reveal the impact of S. japonicum infection on house dust mite induced severe asthma. More in depth investigation is need to elucidate the underlying mechanisms.


Asunto(s)
Inflamación/inmunología , Pyroglyphidae/inmunología , Hipersensibilidad Respiratoria/inmunología , Schistosoma japonicum/inmunología , Esquistosomiasis Japónica/inmunología , Animales , Asma/sangre , Asma/inmunología , Asma/parasitología , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/inmunología , Citocinas/genética , Citocinas/inmunología , Citocinas/metabolismo , Regulación hacia Abajo/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Interacciones Huésped-Parásitos/inmunología , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Inflamación/sangre , Inflamación/parasitología , Ratones Endogámicos C57BL , Neutrófilos/inmunología , Neutrófilos/metabolismo , Pyroglyphidae/fisiología , Hipersensibilidad Respiratoria/sangre , Hipersensibilidad Respiratoria/parasitología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Schistosoma japonicum/fisiología , Esquistosomiasis Japónica/parasitología , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Células Th17/inmunología , Células Th17/metabolismo , Células Th2/inmunología , Células Th2/metabolismo
20.
J Immunol Res ; 2016: 2395645, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27563682

RESUMEN

Invariant natural killer T (iNKT) cells are unique subset of innate-like T cells recognizing glycolipids. iNKT cells can rapidly produce copious amounts of cytokines upon antigen stimulation and exert potent immunomodulatory activities for a wide variety of immune responses and diseases. We have revealed the regulatory effect of iNKT cells on autoimmunity with a serial of publications. On the other hand, the role of iNKT cells in parasitic infections, especially in recently attractive topic "hygiene hypothesis," has not been clearly defined yet. Bacterial and parasitic cell wall is a cellular structure highly enriched in a variety of glycolipids and lipoproteins, some of which may serve as natural ligands of iNKT cells. In this review, we mainly summarized the recent findings on the roles and underlying mechanisms of iNKT cells in parasite infections and their cross-talk with Th1, Th2, Th17, Treg, and innate lymphoid cells. In most cases, iNKT cells exert regulatory or direct cytotoxic roles to protect hosts against parasite infections. We put particular emphasis as well on the identification of the natural ligands from parasites and the involvement of iNKT cells in the hygiene hypothesis.


Asunto(s)
Interacciones Huésped-Parásitos/inmunología , Hipótesis de la Higiene , Células T Asesinas Naturales/inmunología , Enfermedades Parasitarias/inmunología , Enfermedades Parasitarias/parasitología , Subgrupos de Linfocitos T/inmunología , Animales , Citocinas/metabolismo , Humanos , Activación de Linfocitos/inmunología , Células T Asesinas Naturales/metabolismo , Subgrupos de Linfocitos T/metabolismo
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