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1.
Immunity ; 44(2): 246-58, 2016 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-26872695

RESUMEN

Exposure to a plethora of environmental challenges commonly triggers pathological type 2 cell-mediated inflammation. Here we report the pathological role of the Wnt antagonist Dickkopf-1 (Dkk-1) upon allergen challenge or non-healing parasitic infection. The increased circulating amounts of Dkk-1 polarized T cells to T helper 2 (Th2) cells, stimulating a marked simultaneous induction of the transcription factors c-Maf and Gata-3, mediated by the kinases p38 MAPK and SGK-1, resulting in Th2 cell cytokine production. Circulating Dkk-1 was primarily from platelets, and the increase of Dkk-1 resulted in formation of leukocyte-platelet aggregates (LPA) that facilitated leukocyte infiltration to the affected tissue. Functional inhibition of Dkk-1 impaired Th2 cell cytokine production and leukocyte infiltration, protecting mice from house dust mite (HDM)-induced asthma or Leishmania major infection. These results highlight that Dkk-1 from thrombocytes is an important regulator of leukocyte infiltration and polarization of immune responses in pathological type 2 cell-mediated inflammation.


Asunto(s)
Asma/inmunología , Plaquetas/inmunología , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Leishmania major/inmunología , Leishmaniasis Cutánea/inmunología , Células Th2/inmunología , Proteínas Wnt/antagonistas & inhibidores , Animales , Antígenos Dermatofagoides/inmunología , Antígenos de Protozoos/inmunología , Diferenciación Celular , Células Cultivadas , Citocinas/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación de la Expresión Génica , Humanos , Inflamación/inmunología , Péptidos y Proteínas de Señalización Intercelular/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Transgénicos , Modelos Animales , Pyroglyphidae , Transducción de Señal/genética , Serina-Treonina Quinasas TOR/metabolismo
2.
J Immunol ; 201(5): 1359-1372, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30030323

RESUMEN

Follicular helper T (Tfh) cells are necessary for germinal center B cell maturation during primary immune responses; however, the T cells that promote humoral recall responses via memory B cells are less well defined. In this article, we characterize a human tonsillar CD4+ T cell subset with this function. These cells are similar to Tfh cells in terms of expression of the chemokine receptor CXCR5 and the inhibitory receptor PD-1, IL-21 secretion, and expression of the transcription factor BCL6; however, unlike Tfh cells that are located within the B cell follicle and germinal center, they reside at the border of the T cell zone and the B cell follicle in proximity to memory B cells, a position dictated by their unique chemokine receptor expression. They promote memory B cells to produce Abs via CD40L, IL-10, and IL-21. Our results reveal a unique extrafollicular CD4+ T cell subset in human tonsils, which specialize in promoting T cell-dependent humoral recall responses.


Asunto(s)
Formación de Anticuerpos , Linfocitos B/inmunología , Inmunoglobulina G/inmunología , Memoria Inmunológica , Linfocitos T Colaboradores-Inductores/inmunología , Adolescente , Linfocitos B/citología , Niño , Preescolar , Citocinas/inmunología , Femenino , Regulación de la Expresión Génica/inmunología , Humanos , Masculino , Receptor de Muerte Celular Programada 1/inmunología , Proteínas Proto-Oncogénicas c-bcl-6/inmunología , Receptores CXCR5/inmunología , Linfocitos T Colaboradores-Inductores/citología
3.
Ann Rheum Dis ; 76(12): 2061-2064, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28830882

RESUMEN

BACKGROUND: Immune checkpoint inhibitors (ICIs) have significantly improved outcomes for patients with numerous cancers. However, these therapies are associated with immune-related adverse events (irAEs), which are inflammatory side effects potentially affecting any organ. Cases of ICI-induced inflammatory arthritis have also been reported. In general, mild irAEs are treated with corticosteroids, while tumour necrosis factor-α (TNFα) inhibitors are reserved for refractory cases. However, prolonged use of TNFα inhibitor (TNFαi) can induce widespread, significant immunosuppression, which can negatively impact the antitumour efficacy of ICI therapy. Therefore, in clinical scenarios where patients develop severe immunotherapy-induced irAEs, an unmet need exists for alternative therapeutic strategies that are effective and without immune dampening effects. CASE REPORTS: The anti-interleukin (IL)-6 receptor antibody, tocilizumab, is a biological agent Food and Drug Administration approved for the treatment of rheumatoid arthritis and juvenile idiopathic arthritis. Here, we report on three patients who developed severe polyarthritis while receiving ICI therapy and were treated with tocilizumab. All three patients demonstrated significant clinical improvement; one patient maintained a durable antitumour response derived from checkpoint inhibition. CONCLUSIONS: These three cases suggest that anti-IL-6 receptor antibody may be an effective alternative to corticosteroids or TNFαi for the treatment of arthritis irAEs.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Antirreumáticos/administración & dosificación , Artritis/inducido químicamente , Inmunosupresores/efectos adversos , Inmunoterapia/efectos adversos , Anciano , Artritis/inmunología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Puntos de Control del Ciclo Celular/inmunología , Femenino , Humanos , Inmunoterapia/métodos , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
4.
Cancers (Basel) ; 15(15)2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37568819

RESUMEN

Patients with pre-existing autoimmune disorders and cancer considering immune checkpoint inhibitors (ICIs) need to receive balanced information about the benefits and risk of developing immune-related adverse events (irAEs) and flare-ups of their autoimmune disease. To assess the learning needs of patients with cancer and pre-existing autoimmune disease regarding ICI treatment, we interviewed 29 patients with autoimmune disease and cancer from a comprehensive cancer center, of whom 20 had received ICI and 9 were candidates to receive ICI at a US Cancer Center. In-depth semi-structured interviews were conducted from August 2021 and January 2022. Interviewee's opinions and preferences about content and information delivery methods were collected. We recorded and transcribed interviews and analyzed them using thematic analysis. Half of the participants were female, and their median (SD) age was 62.9 (±10.9) years. The identified health information needs included the following: (1) information on irAEs and autoimmune disease flare-ups; (2) benefits of ICI; (3) ICI mechanism in the context of autoimmune disease; (4) management of flare-ups; (5) reasons for stopping or modifying cancer or autoimmune disease treatment; (6) likelihood of autoimmune disease progression or organ damage; and (7) lifestyle changes that could help avoid irAEs. Patients who had received ICI and those who had not yet received treatment reported similar needs, although patients who had received ICI had more questions about cancer treatment modifications. Patients also expressed the need to better understand when to contact their provider and how to share information with multiple providers. Most patients wanted to receive information in visual formats for review at home and at their own pace. Patients expressed interest in having educational tools to facilitate shared decision-making with their physicians, and they identified several areas of health information concerning therapy with ICI. They also highlighted the importance of communication among their various providers.

5.
Clin Lung Cancer ; 20(3): e299-e308, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30824332

RESUMEN

BACKGROUND: Lung cancer is one of the most lethal malignancies, with a 5-year survival rate < 20% in patients with stage IV lung cancer. Impaired host immunity is associated with lung cancer pathogenesis, and interferon gamma (IFN-γ) plays an important role in antitumor immune surveillance. We evaluated the clinical significance of ex vivo production of IFN-γ in patients with lung adenocarcinoma. PATIENTS AND METHODS: We reviewed the medical records of 109 treatment-naive patients with lung adenocarcinoma who had undergone IFN-γ releasing assay. Differences in the IFN-γ level in nil and mitogen tubes were defined as ex vivo IFN-γ production. Correlation analysis was performed to evaluate the correlation between ex vivo IFN-γ production, cancer staging, and Eastern Cooperative Oncology Group performance status. The optimal cutoff values of low and high ex vivo IFN-γ production were estimated using receiver operator characteristic curve analysis. Cox proportional hazard analyses were used to evaluate the prognostic factors of 1-year overall patient survival. RESULTS: Ex vivo IFN-γ production correlated with N stage, M stage, cancer staging, and Eastern Cooperative Oncology Group performance status. Low ex vivo IFN-γ production (ex vivo IFN-γ production ≤ 7.79 IU/mL) was independently associated with 1-year overall survival (odds ratio = 3.289; 95% confidence interval, 1.573-6.872; P = .002). Additionally, low ex vivo IFN-γ production was an independent predictor of 1-year overall survival in patients with stage IV cancer (odds ratio = 3.156; 95% confidence interval, 1.473-6.760; P = .003). CONCLUSION: Ex vivo IFN-γ production before treatment might be a useful biomarker for predicting prognosis in patients with lung adenocarcinoma.


Asunto(s)
Adenocarcinoma del Pulmón/diagnóstico , Interferón gamma/metabolismo , Células Asesinas Naturales/inmunología , Neoplasias Pulmonares/diagnóstico , Linfocitos T/inmunología , Adenocarcinoma del Pulmón/inmunología , Adenocarcinoma del Pulmón/mortalidad , Anciano , Biomarcadores , Células Cultivadas , Femenino , Humanos , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Análisis de Supervivencia
6.
Opt Express ; 16(25): 21053-8, 2008 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-19065245

RESUMEN

Novel triangular ring resonators combining extremely small multimode-interference (MMI) coupler, low loss total internal reflection (TIR) mirrors, and semiconductor optical amplifiers are reported for the first time. The MMI length of 90 microm is among the shortest reported. The incidence angle of the TIR mirror inside the resonator is 22 degrees. A free-spectral range of approximately 2 nm is observed near 1550 nm along with an on-off ratio of 17 dB. The triangular resonators with a sharp angle are very attractive components due to their promise of compact size and high levels of integration. Therefore, large numbers of resonators can be integrated on a chip to increase functionality in future optical wavelength division multiplexing system.


Asunto(s)
Diseño Asistido por Computadora , Lentes , Modelos Teóricos , Refractometría/instrumentación , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Miniaturización , Dispersión de Radiación , Semiconductores , Integración de Sistemas , Vibración
7.
Arthritis Rheumatol ; 67(4): 988-99, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25581113

RESUMEN

OBJECTIVE: To assess circulating follicular helper T (Tfh)-like CD4+ T cells in patients with systemic lupus erythematosus (SLE) and determine their relationship to disease activity. METHODS: Blood samples from patients with SLE, as well as blood samples from patients with Behçet's disease (BD) and healthy individuals as controls, were analyzed. In all samples, circulating Tfh-like cells were enumerated by flow cytometry, using, as markers, expression of CXCR5, inducible T cell costimulator (ICOS), and programmed death 1 (PD-1) protein, as well as secretion of interleukin-21 (IL-21). The frequency of circulating Tfh-like cells was compared to that of circulating plasmablasts (CD19+IgD-CD38+). In addition, the possible association of circulating Tfh-like cells with the SLE Disease Activity Index (SLEDAI) was evaluated. RESULTS: The subset of circulating Tfh-like T cells, identified as CXCR5(high) ICOS(high) PD-1(high) , was expanded in the blood of SLE patients compared to controls. Circulating Tfh-like cells were found to produce IL-21 and had lower expression of CCR7 as compared to that in circulating CXCR5(high) central memory T cells, thereby enabling their distinction. Expression of PD-1, but not ICOS or CXCR5, was significantly elevated in circulating Tfh-like cells from SLE patients compared to controls. PD-1 expression among CXCR5(high) circulating Tfh-like cells correlated with the SLEDAI, frequency of circulating plasmablasts, and anti-double-stranded DNA antibody positivity, but not with disease duration or past organ injury; rather, this cell profile appeared to be a reflection of current active disease. CONCLUSION: Circulating Tfh-like cells are associated with disease activity in SLE, suggesting that their presence indicates abnormal homeostasis of T cell-B cell collaboration, with a causal relationship that is central to disease pathogenesis. These findings also suggest that circulating Tfh-like cells provide a surrogate for aberrant germinal center activity in SLE, and that their PD-1 expression offers a tool for measuring disease activity and monitoring the response to therapies.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Lupus Eritematoso Sistémico/sangre , Linfocitos T Colaboradores-Inductores/inmunología , Adulto , Autoanticuerpos/sangre , Síndrome de Behçet/sangre , Síndrome de Behçet/inmunología , Linfocitos T CD4-Positivos/metabolismo , ADN/inmunología , Femenino , Humanos , Interleucinas/metabolismo , Lupus Eritematoso Sistémico/inmunología , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Linfocitos T Colaboradores-Inductores/metabolismo
8.
Curr Opin Immunol ; 24(6): 651-7, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23131610

RESUMEN

Systemic lupus erythematosus (SLE, lupus) is characterized by a global loss of self-tolerance with activation of autoreactive T and B cells leading to production of pathogenic autoantibodies and tissue injury. Innate immune mechanisms are necessary for the aberrant adaptive immune responses in SLE. Recent advances in basic and clinical biology have shed new light on disease mechanisms in lupus, with this review discussing the recent studies that offer valuable insights into disease-specific therapeutic targets.


Asunto(s)
Lupus Eritematoso Sistémico/etiología , Autoanticuerpos/inmunología , Autoinmunidad/fisiología , Linfocitos B/inmunología , Humanos , Inmunidad Innata , Linfocitos T/inmunología
9.
Opt Lett ; 29(19): 2243-5, 2004 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-15524368

RESUMEN

Multisection semiconductor lasers for optical microwave generation have been fabricated that consist of a loss-coupled distributed feedback (LC-DFB), a phase control, and an amplifier section. High-frequency self-pulsations are generated according to the concept of a single-mode laser with short optical feedback. The effect of the optical feedback via the phase control and the amplifier section on the self-pulsation is apparently shown as a result of the superior single-mode characteristic of the LC-DFB section. Continuous frequency tuning is achieved in the range of 17-35 GHz.

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