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1.
J Heart Lung Transplant ; 40(11): 1267-1278, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34404570

RESUMEN

Patients with connective tissue disease (CTD) present unique surgical, perioperative, operative, and postoperative challenges related to the often underlying severe pulmonary hypertension and right ventricular dysfunction. The International Society for Heart and Lung Transplantation-supported consensus document on lung transplantation in patients with CTD standardization addresses the surgical challenges and relevant cardiac involvement in the perioperative, operative, and postoperative management in patients with CTD.


Asunto(s)
Enfermedades del Tejido Conjuntivo/cirugía , Manejo de la Enfermedad , Trasplante de Pulmón/normas , Atención Perioperativa/normas , Consenso , Humanos
2.
J Immunol ; 203(8): 2063-2075, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31554693

RESUMEN

CMV remains an important opportunistic pathogen in high-risk lung transplant recipients. We characterized the phenotype and function of CD8+ T cells from acute/primary into chronic CMV infection in 23 (donor+/recipient-; D+R-) lung transplant recipients and found rapid induction of both KLRG1+ and/or CD57+ CMV-specific CD8+ T cells with unexpected coexpression of CD27. These cells demonstrated maturation from an acute effector T cell (TAEFF) to an effector memory T cell (TEM) phenotype with progressive enrichment of KLRG1+CD57+CD27- cells into memory. CMV-specific KLRG1+ TAEFF were capable of in vitro proliferation that diminished upon acquisition of CD57, whereas only KLRG1+ expression correlated with T-bet expression and effector function. In contrast to blood TAEFF, lung mucosal TAEFF demonstrated reduced KLRG1/T-bet expression but similar CD57 levels. Additionally, increased KLRG1+TAEFF were associated with early immune viral control following primary infection. To our knowledge, our findings provide new insights into the roles of KLRG1 and CD57 expression in human T cells, forming the basis for a refined model of CD8+ T cell differentiation during CMV infection.


Asunto(s)
Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/virología , Citomegalovirus/inmunología , Lectinas Tipo C/inmunología , Receptores Inmunológicos/inmunología , Adulto , Antígenos CD57/inmunología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Diferenciación Celular/inmunología , Proliferación Celular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
3.
Am J Respir Crit Care Med ; 199(3): 362-376, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30088779

RESUMEN

RATIONALE: Cytomegalovirus (CMV)-related morbidities remain one of the most common complications after lung transplantation and have been linked to allograft dysfunction, but the factors that predict high risk for CMV complications and effective immunity are incompletely understood. OBJECTIVES: To determine if short telomeres in idiopathic pulmonary fibrosis (IPF) lung transplant recipients (LTRs) predict the risk for CMV-specific T-cell immunity and viral control. METHODS: We studied IPF-LTRs (n = 42) and age-matched non-IPF-LTRs (n = 42) and assessed CMV outcomes. We measured lymphocyte telomere length and DNA sequencing, and assessed CMV-specific T-cell immunity in LTRs at high risk for CMV events, using flow cytometry and fluorescence in situ hybridization. MEASUREMENTS AND MAIN RESULTS: We identified a high prevalence of relapsing CMV viremia in IPF-LTRs compared with non-IPF-LTRs (69% vs. 31%; odds ratio, 4.98; 95% confidence interval, 1.95-12.50; P < 0.001). Within this subset, IPF-LTRs who had short telomeres had the highest risk of CMV complications (P < 0.01) including relapsing-viremia episodes, end-organ disease, and CMV resistance to therapy, as well as shorter time to viremia versus age-matched non-IPF control subjects (P < 0.001). The short telomere defect in IPF-LTRs was associated with significantly impaired CMV-specific proliferative responses, T-cell effector functions, and induction of the major type-1 transcription factor T-bet (T-box 21;TBX21). CONCLUSIONS: Because the short telomere defect has been linked to the pathogenesis of IPF in some cases, our data indicate that impaired CMV immunity may be a systemic manifestation of telomere-mediated disease in these patients. Identifying this high-risk subset of LTRs has implications for risk assessment, management, and potential strategies for averting post-transplant CMV morbidities.


Asunto(s)
Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/inmunología , Fibrosis Pulmonar Idiopática/complicaciones , Trasplante de Pulmón , Telómero/inmunología , Receptores de Trasplantes/estadística & datos numéricos , Adulto , Anciano , Citomegalovirus/inmunología , Femenino , Humanos , Fibrosis Pulmonar Idiopática/inmunología , Inmunidad , Masculino , Persona de Mediana Edad
4.
Transplant Direct ; 4(5): e350, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29796421

RESUMEN

BACKGROUND: Acute cellular rejection (ACR) is a major risk factor for chronic lung allograft dysfunction after lung transplantation. Acute cellular rejection can persist or recur despite augmentation of immunosuppression by conventional methods. There are limited therapeutic options in treating these recurrent and refractory ACRs. We describe our experience with cyclophosphamide therapy for recurrent and refractory ACR in lung transplant recipients. METHODS: Six consecutive patients who were treated with cyclophosphamide for recurrent or refractory ACR were included in the series. The primary outcome measures were improvement in ACR score and forced expiratory volume at 1 second. Secondary outcome measures included adverse drug events including bone marrow suppression, gastrointestinal side effects, and infections. RESULTS: Five of the 6 patients treated demonstrated complete resolution of ACR on follow-up biopsies. Acute cellular rejection score improved after cyclophosphamide treatment (P = 0.03). None of the patients had high grade (≥A3) ACR in the 3 months after cyclophosphamide administration. Cyclophosphamide had no effect on forced expiratory volume at 1 second trend or bronchiolitis obliterans score. All patients tolerated cyclophosphamide with minor gastrointestinal side effects, mild bone marrow suppression, and nonfatal infections that were amenable to treatment. CONCLUSIONS: Cyclophosphamide therapy is an option in treating recurrent and refractory ACR in patients who have failed conventional treatments. Cyclophosphamide is tolerated well without serious adverse drug events (ADE).

5.
J Immunol ; 196(2): 877-90, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26663780

RESUMEN

CMV remains an important opportunistic pathogen in solid organ and hematopoietic cell transplantation, particularly in lung transplant recipients (LTRs). LTRs mismatched for CMV (donor(+)/recipient(-); D(+)R(-)) are at high risk for active CMV infection and increased mortality; however, the immune correlates of viral control remain incompletely understood. We prospectively studied 27 D(+)R(-) LTRs during primary CMV infection to determine whether acute CD4(+) T cell parameters differentiated the capacity for viral control during early chronic infection. Unexpectedly, the T-box transcription factor, T-bet, was expressed at low levels in CD4(+) compared with CD8(+) T cells during acute primary infection. However, the capacity for in vitro CMV phosphoprotein 65-specific proliferation and CD4(+)T-bet(+) induction differentiated LTR controllers from early viremic relapsers, correlating with granzyme B loading and effector multifunction. Furthermore, impaired CMV-specific proliferative responses from relapsers, along with T-bet, and effector function could be significantly rescued, most effectively with phosphoprotein 65 Ag and combined exogenous IL-2 and IL-12. Acute CD4(+) T cell CMV-specific proliferative and effector responses were highly IL-12-dependent in blocking studies. In addition, we generated monocyte-derived dendritic cells using PBMC obtained during primary infection from relapsers and observed impaired monocyte-derived dendritic cell differentiation, a reduced capacity for IL-12 production, but increased IL-10 production compared with controls, suggesting an APC defect during acute CMV viremia. Taken together, these data show an important role for CMV-specific CD4(+) effector responses in differentiating the capacity of high-risk LTRs to establish durable immune control during early chronic infection and provide evidence for IL-12 as a key factor driving these responses.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Infecciones por Citomegalovirus/inmunología , Trasplante de Pulmón/efectos adversos , Activación de Linfocitos/inmunología , Proteínas de Dominio T Box/biosíntesis , Adulto , Proliferación Celular , Células Cultivadas , Citomegalovirus/inmunología , Células Dendríticas/inmunología , Células Dendríticas/virología , Femenino , Citometría de Flujo , Humanos , Interleucina-12 , Masculino , Persona de Mediana Edad , Proteínas de Dominio T Box/inmunología , Adulto Joven
6.
Viral Immunol ; 28(5): 255-64, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26046830

RESUMEN

Cytomegalovirus (CMV) is a significant cause of morbidity and mortality in immunocompromised hosts, many of whom undergo significant periods of lymphopenia. However, the impact of lymphopenia and subsequent immune reconstitution on T cell responses and pulmonary pathology are poorly understood. Using a model of primary murine CMV infection in mice treated with cyclophosphamide (CY), the relationship of CD8+ T cell reconstitution to pneumonitis pathology was studied. Female BALB/c mice were infected with murine CMV (MCMV) with/without CY on day 1 post-infection. Lung pathology and viral specific T cell responses were assessed on days 7-28. T cell lymphocyte subsets, effector responses, and MCMV specificity were assessed at baseline and after in vitro stimulation of cells with immediate-early peptide pp89. CY treatment of MCMV-infected mice resulted in interstitial pneumonitis not seen with MCMV alone. Compared to MCMV alone, on day 14, MCMV/CY mice had greater number of CD8+ T cells, a fourfold increase in absolute number of pp89 tetramer-specific CD8+ cells, and an eightfold increase in MCMV specific T cell effector responses (IFN-γ; p<0.001). This expansion was preceded by transient lymphopenia, increased viral titers, and, most strikingly, a 10-fold increased proliferative capacity in MCMV/CY mice. In the setting of CY-associated lymphopenia, concurrent MCMV infection alters immune reconstitution toward a hyperexpanded MCMV-specific CD8+ effector T cell pool that correlates with significant lung immunopathology.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por Herpesviridae/inmunología , Huésped Inmunocomprometido/inmunología , Linfopenia/inmunología , Muromegalovirus/inmunología , Animales , Ciclofosfamida , Femenino , Infecciones por Herpesviridae/virología , Proteínas Inmediatas-Precoces/inmunología , Interferón gamma/inmunología , Pulmón/inmunología , Pulmón/patología , Recuento de Linfocitos , Linfopenia/virología , Ratones , Ratones Endogámicos BALB C , Neumonía/inmunología , Neumonía/virología , Subgrupos de Linfocitos T/inmunología
7.
J Heart Lung Transplant ; 34(4): 557-62, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25447582

RESUMEN

BACKGROUND: Exhaled nitric oxide (FeNO), a marker of airway inflammation, is often elevated in lung transplant recipients (LTxRs) with acute rejection or infection. Isolated measurements in the setting of bronchiolitis obliterans syndrome have been variable. We sought to assess the utility of serial FeNO in predicting chronic allograft dysfunction or the presence of acute rejection or infection. METHODS: Eighty-six LTxRs underwent 325 serial FeNO measurements at an expiratory flow rate of 50 ml/s. The change in FeNO (ΔFeNO) between two measurements obtained during a stable state (ΔFeNO-SS) was compared with ΔFeNO, where the first measurement was taken during a stable state and the second during an unstable state (defined as a subsequent decline in FEV1 > 10% over 3 months [ΔFeNO-SU]) or an acute complication (acute rejection, lymphocytic bronchiolitis or acute infection [ΔFeNO-SAC]). The median follow-up time after the baseline FeNO was 10 (range 3 to 25) months. RESULTS: ΔFeNO-SS in 117 FeNO pairs was similar to ΔFeNO-SU in 26 pairs (2.1 ± 3 ppb vs 2.3 ± 4 ppb; p = 0.2). ΔFeNO-SAC in 17 pairs was markedly increased (27 ± 20 ppb; p < 0.001 vs ΔFeNO-SS). The area under the receiver-operating characteristic curve for ΔFeNO in detecting an acute complication was 0.93 (p < 0.001). By applying a cut-off of >10 ppb, the sensitivity and specificity was 82% and 100%, respectively, with positive and negative predictive values of 100% and 97.5%. CONCLUSIONS: Changes in FeNO may serve as a useful adjunct in the detection of acute complications after lung transplantation. In this limited analysis, ΔFeNO was not predictive of a subsequent decline in allograft function.


Asunto(s)
Trasplante de Pulmón , Óxido Nítrico/análisis , Complicaciones Posoperatorias/diagnóstico , Enfermedad Aguda , Pruebas Respiratorias/métodos , Espiración , Femenino , Humanos , Masculino , Persona de Mediana Edad
8.
J Heart Lung Transplant ; 33(12): 1288-94, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25443870

RESUMEN

BACKGROUND: The development of human leukocyte antigen (HLA) antibody responses has been associated with worse clinical outcomes, such as bronchiolitis obliterans syndrome (BOS) and death, in lung transplant recipients (LTRs). However, the role of donor-specific HLA antibody (DSA) responses as a risk factor for poor outcomes remains controversial. METHODS: We prospectively screened 445 LTRs for DSA at our institution at the time of surveillance bronchoscopies for the first 2 years after transplantation between 2003 and 2008, and evaluated clinical outcomes. For this purpose, we used the combination of panel-reactive antibodies (PRA) by enzyme-linked immunosorbent assay (ELISA) and the Luminex single-antigen bead (SAB) assay (One Lambda, Canoga Park, CA). RESULTS: We detected de novo DSA (dnDSA) in 58 of 445 (13%) LTRs in our cohort. Freedom from BOS was significantly reduced in LTRs with dnDSA versus those without dnDSA (p < 0.001). Using a Cox proportional hazards model, the development of dnDSA was associated with a significantly increased hazard ratio (HR = 6.59 [4.53 to 9.59]; p < 0.001) for BOS and high-grade BOS (Stage ≥ 2) (HR = 5.76 [3.48 to 9.52]; p < 0.001). Freedom from death was significantly reduced in LTRs with dnDSA (p < 0.001), including mortality attributable to BOS (HR = 9.86 [4.91 to 19.78]; p < 0.001). CONCLUSIONS: Taken together, our findings provide evidence that dnDSA is associated with accelerated BOS kinetics and severity, as well as death due to BOS after lung transplantation. In addition, these data support regular monitoring for the development of dnDSA in LTRs and underscore the need for novel strategies to mitigate the increased risk of poor outcomes associated with dnDSA.


Asunto(s)
Anticuerpos Antiidiotipos/metabolismo , Bronquiolitis Obliterante/epidemiología , Bronquiolitis Obliterante/mortalidad , Antígenos HLA/inmunología , Trasplante de Pulmón , Donantes de Tejidos , Adulto , Anciano , Biomarcadores/metabolismo , Bronquiolitis Obliterante/inmunología , Broncoscopía , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Pulmón/inmunología , Pulmón/patología , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia
9.
J Immunol ; 193(11): 5709-5722, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25339676

RESUMEN

CMV remains an important opportunistic pathogen in solid organ transplantation, particularly in lung transplant recipients (LTRs). LTRs mismatched for CMV (donor+/recipient-; D+R-) are at high-risk for active CMV infection and increased mortality, however the immune correlates of viral control remain incompletely understood. We prospectively studied 23 D+R- LTRs during primary CMV infection to determine whether acute CD8(+) T cell parameters differentiated the capacity for viral control in early chronic infection. T-box transcription factors expression patterns of T-bet > Eomesodermin (Eomes) differentiated LTR controllers from viremic relapsers and reciprocally correlated with granzyme B loading, and CMV phosphoprotein 65 (pp65)-specific CD8(+)IFN-γ(+) and CD107a(+) frequencies. LTR relapsers demonstrated reduced CD8(+)Ki67(+) cells ex vivo and substantially impaired CD8(+)pp65-specific in vitro proliferative responses at 6 d, with concomitantly lower pp65-specific CD4(+)IL-2(+) frequencies, as compared with LTR controllers. However, CMV-specific in vitro proliferative responses could be significantly rescued, most effectively with pp65 Ag and exogenous IL-2, resulting in an increased T-bet:Eomes balance, and enhanced effector function. Using class I CMV tetramers, we observed similar frequencies between relapsers and controllers, although reduced T-bet:Eomes balance in tetramer(+) cells from relapsers, along with impaired CD8(+) effector responses to tetramer-peptide restimulation. Taken together, these data show impaired CMV-specific CD8(+) effector responses is not for complete lack of CMV-specific cells but rather underscores the importance of the T-bet:Eomes balance, with CMV-specific proliferation a key factor driving early T-bet expression and effector function in CD8(+) T cells during primary infection and differentiating the capacity of high-risk LTRs to establish immune control during early chronic infection.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Infecciones por Citomegalovirus/inmunología , Citomegalovirus/inmunología , Trasplante de Pulmón , Complicaciones Posoperatorias/inmunología , Proteínas de Dominio T Box/metabolismo , Adulto , Linfocitos T CD4-Positivos/virología , Linfocitos T CD8-positivos/virología , Proliferación Celular , Células Cultivadas , Enfermedad Crónica , Infecciones por Citomegalovirus/prevención & control , Citotoxicidad Inmunológica , Femenino , Humanos , Interferón gamma/metabolismo , Interleucina-2/metabolismo , Masculino , Persona de Mediana Edad , Fosfoproteínas/inmunología , Complicaciones Posoperatorias/prevención & control , Estudios Prospectivos , Recurrencia , Proteínas de Dominio T Box/genética , Proteínas de la Matriz Viral/inmunología , Adulto Joven
10.
Methods Mol Biol ; 1186: 21-47, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25149301

RESUMEN

Cytotoxic T lymphocytes (CTLs) are important constituents of the adaptive immune system. Development of CTLs are particularly important for bacterial and viral infections, in addition to tumor surveillance. Measuring T cell immune function is important in evaluating host defense, allergy, autoimmunity, transplant rejection, and tumor immunity. In these recent years it has become possible to measure multiple effector functions in a single cell such as cytokine, transcription factors, and cytolytic function. In addition these parameters can be evaluated in conjunction with cellular proliferation. In this chapter we detail these cellular based assays and the methods used to characterize and quantify both phenotype and function of CTL.


Asunto(s)
Citomegalovirus/inmunología , Citometría de Flujo/métodos , Linfocitos T Citotóxicos/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Inmunidad Adaptativa/inmunología , Apoptosis/inmunología , Línea Celular , Proliferación Celular , Citocinas/inmunología , Citocinas/metabolismo , Células Dendríticas/inmunología , Proteína Ligando Fas/inmunología , Granzimas/biosíntesis , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Memoria Inmunológica/inmunología , Antígeno Ki-67/metabolismo , Antígenos Comunes de Leucocito/biosíntesis , Activación de Linfocitos/inmunología , Proteína 1 de la Membrana Asociada a los Lisosomas/metabolismo , Microesferas , Perforina/biosíntesis , Receptores de Antígenos de Linfocitos T/inmunología , Coloración y Etiquetado , Linfocitos T Citotóxicos/citología , Receptor fas/inmunología
11.
Ann Thorac Surg ; 94(1): 185-92, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22325467

RESUMEN

BACKGROUND: Acute kidney injury requiring renal replacement therapy (RRT) is associated with increased mortality after cardiac surgery. Studies examining the impact of RRT after lung transplantation (LTx) are limited. We evaluated risk factors and outcomes associated with RRT after LTx. METHODS: We retrospectively reviewed all LTx recipients in the United Network for Organ Sharing database. Preoperative renal function was stratified by glomerular filtration rate (GFR) as determined by the Modification of Diet in Renal Disease formula (strata: ≥90, 60 to 90, and <60 mL · min(-1) · 1.73 m(-2)). Primary outcomes were 30-day, 1-year, and 5-year survival and need for post-LTx RRT. Risk adjusted multivariable Cox proportional hazards regression examined mortality. A multivariable logistic regression model evaluated risk factors for RRT. RESULTS: From 2001 to 2011, 12,108 patients underwent LTx. After LTx, 655 patients (5.51%) required RRT. Patients requiring post-LTx RRT had decreased survival at 30 days (96.7% versus 76.0%, p < 0.001), 1 year (85.5% versus 35.8%, p < 0.001), and 5 years (56.4% versus 20.0%, p < 0.001). These differences persisted on multivariable analysis at 30 days (hazard ratio [HR] 7.98 [6.16 to 10.33], p < 0.001), 1 year (HR 7.93 [6.84 to 9.19], p < 0.001), and 5 years (HR 5.39 [4.75 to 6.11], p < 0.001). Preoperative kidney function was an important predictor of post-LTx RRT for a GFR of 60 to 90 (odds ratio 1.42 [1.16 to 1.75], p = 0.001) and a GFR less than 60 (odds ratio 2.68 [2.07 to 3.46], p < 0.001]. High center volume was protective. CONCLUSIONS: In the largest study to evaluate acute kidney injury after LTx, the incidence of RRT is 5.51%. The need for post-LTx RRT dramatically increases both short- and long-term mortality. Several variables, including preoperative renal function, are predictors of post-LTx RRT and could be used to identify transplant candidates at risk for acute kidney injury.


Asunto(s)
Lesión Renal Aguda/etiología , Trasplante de Pulmón/efectos adversos , Lesión Renal Aguda/mortalidad , Adulto , Anciano , Estudios de Cohortes , Oxigenación por Membrana Extracorpórea , Femenino , Tasa de Filtración Glomerular , Humanos , Modelos Logísticos , Trasplante de Pulmón/mortalidad , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
12.
J Infect Dis ; 204(11): 1663-71, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22021622

RESUMEN

BACKGROUND: Cytomegalovirus (CMV) remains an important pathogen in solid organ transplantation, particularly lung transplantation. Lung transplant recipients (LTRs) mismatched for CMV (donor positive/recipient negative [D(+)R(-)]) are at highest risk for active CMV infection and have increased mortality. However, the correlates of immune control during chronic CMV infection remain incompletely understood. METHODS: We prospectively studied 22 D(+)R(-) LTRs during primary CMV infection and into chronic infection. Immune responses during primary infection were analyzed for association with viral relapse during early chronic infection. RESULTS: Primary CMV infection was characterized by a striking induction of T-box transcription factor (T-bet) in CD8(+) T cells. CMV-specific effector CD8(+) T cells were found to be T-bet(+). After primary infection, 7 LTRs lacked immune control with relapsing viremia during early chronic infection. LTRs with relapsing viremia had poor induction of T-bet and low frequencies of phosphoprotein 65 (pp65)-specific CD8(+) effector T cells during primary infection. However, frequencies of IE1-specific CD8(+) effector T cells during primary infection were not associated with early relapsing viremia. CONCLUSIONS: T-bet plays an important role in coordinating CD8(+) effector responses to CMV during primary infection. Moreover, CD8(+) T-bet induction and pp65-specific CD8(+) effector responses at the time of primary infection are important predictors of immune control of CMV during early chronic infection.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por Citomegalovirus/inmunología , Citomegalovirus/inmunología , Trasplante de Pulmón/inmunología , Fosfoproteínas/inmunología , Proteínas de la Matriz Viral/inmunología , Adulto , Linfocitos T CD8-positivos/metabolismo , Enfermedad Crónica , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Citomegalovirus/transmisión , Infecciones por Citomegalovirus/virología , Femenino , Humanos , Proteínas Inmediatas-Precoces/inmunología , Interferón gamma/sangre , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Curva ROC , Recurrencia , Estadísticas no Paramétricas , Proteínas de Dominio T Box/metabolismo , Viremia/inmunología , Adulto Joven
13.
JAMA ; 304(22): 2521-7, 2010 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-21139113

RESUMEN

Acute respiratory distress syndrome (ARDS) is a common and severe form of acute lung injury, resulting from both direct (eg, pneumonia) and indirect (eg, sepsis) pulmonary insults. It is a common cause of admission to the intensive care unit due to hypoxemic respiratory failure requiring mechanical ventilation, and is associated with significant morbidity and mortality. In some patients, ARDS leads to the development of life-threatening refractory hypoxemia. In these patients, physicians may consider a number of therapies (eg, recruitment maneuvers, prone positioning, inhaled nitric oxide, high-frequency oscillatory ventilation, extracorporeal membrane oxygenation) to alleviate hypoxemia in patients unable to maintain reasonable oxygenation while being supported with conventional mechanical ventilation. Although these strategies have demonstrated improved oxygenation with their use, their impact on patient-important outcomes (eg, mortality) remains unproven. However, in the minority of patients with ARDS and refractory hypoxemia, institution of these therapies may be considered on a case-by-case basis. Future studies are needed to elucidate the efficacy of these therapies on outcomes in patients with severe ARDS and refractory hypoxemia.


Asunto(s)
Hipoxia/etiología , Hipoxia/terapia , Respiración Artificial/métodos , Síndrome de Dificultad Respiratoria/complicaciones , Lesión Pulmonar Aguda/complicaciones , Lesión Pulmonar Aguda/cirugía , Adulto , Oxigenación por Membrana Extracorpórea , Humanos , Trasplante de Pulmón , Masculino , Óxido Nítrico/administración & dosificación , Posición Prona
14.
J Clin Invest ; 119(10): 2898-913, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19770521

RESUMEN

Acute lung injury (ALI) is characterized by rapid alveolar injury, inflammation, cytokine induction, and neutrophil accumulation. Although early events in the pathogenesis of ALI have been defined, the mechanisms underlying resolution are unknown. As a model of ALI, we administered intratracheal (i.t.) LPS to mice and observed peak lung injury 4 days after the challenge, with resolution by day 10. Numbers of alveolar lymphocytes increased as injury resolved. To examine the role of lymphocytes in this response, lymphocyte-deficient Rag-1-/- and C57BL/6 WT mice were exposed to i.t. LPS. The extent of injury was similar between the groups of mice through day 4, but recovery was markedly impaired in the Rag-1-/- mice. Adoptive transfer studies revealed that infusion of CD4+CD25+Foxp3+ Tregs as late as 24 hours after i.t. LPS normalized resolution in Rag-1-/- mice. Similarly, Treg depletion in WT mice delayed recovery. Treg transfer into i.t. LPS-exposed Rag-1-/- mice also corrected the elevated levels of alveolar proinflammatory cytokines and increased the diminished levels of alveolar TGF-beta and neutrophil apoptosis. Mechanistically, Treg-mediated resolution of lung injury was abrogated by TGF-beta inhibition. Moreover, BAL of patients with ALI revealed dynamic changes in CD3+CD4+CD25hiCD127loFoxp3+ cells. These results indicate that Tregs modify innate immune responses during resolution of lung injury and suggest potential targets for treating ALI, for which there are no specific therapies currently available.


Asunto(s)
Lesión Pulmonar Aguda , Linfocitos T CD4-Positivos/inmunología , Factores de Transcripción Forkhead/inmunología , Subunidad alfa del Receptor de Interleucina-2/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T Reguladores/inmunología , Lesión Pulmonar Aguda/inmunología , Lesión Pulmonar Aguda/patología , Animales , Líquido del Lavado Bronquioalveolar/citología , Células Cultivadas , Factores de Transcripción Forkhead/genética , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Interleucina-10/inmunología , Lipopolisacáridos/inmunología , Pulmón/inmunología , Pulmón/patología , Macrófagos Peritoneales/citología , Macrófagos Peritoneales/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neutrófilos/citología , Neutrófilos/inmunología , Tasa de Supervivencia , Subgrupos de Linfocitos T/citología , Linfocitos T Reguladores/citología
15.
J Virol ; 83(6): 2728-42, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19129459

RESUMEN

To better understand the components of an effective immune response to human immunodeficiency virus (HIV), the CD8(+) T-cell responses to HIV, hepatitis C virus (HCV), and cytomegalovirus (CMV) were compared with regard to frequency, immunodominance, phenotype, and interleukin-2 (IL-2) responsiveness. Responses were examined in rare patients exhibiting durable immune-mediated control over HIV, termed long-term nonprogressors (LTNP) or elite controllers, and patients with progressive HIV infection (progressors). The magnitude of the virus-specific CD8(+) T-cell response targeting HIV, CMV, and HCV was not significantly different between LTNP and progressors, even though their capacity to proliferate to HIV antigens was preserved only in LTNP. In contrast to HIV-specific CD8(+) T-cell responses of LTNP, HLA B5701-restricted responses within CMV pp65 were rare and did not dominate the total CMV-specific response. Virus-specific CD8(+) T cells were predominantly CD27(+)45RO(+) for HIV and CD27(-)45RA(+) for CMV; however, these phenotypes were highly variable and heavily influenced by the degree of viremia. Although IL-2 induced significant expansions of CMV-specific CD8(+) T cells in LTNP and progressors by increasing both the numbers of cells entering the proliferating pool and the number of divisions, the proliferative capacity of a significant proportion of HIV-specific CD8(+) T cells was not restored with exogenous IL-2. These results suggest that immunodominance by HLA B5701-restricted cells is specific to HIV infection in LTNP and is not a feature of responses to other chronic viral infections. They also suggest that poor responsiveness to IL-2 is a property of HIV-specific CD8(+) T cells of progressors that is not shared with responses to other viruses over which immunologic control is maintained.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por Citomegalovirus/inmunología , Infecciones por VIH/inmunología , Hepatitis C/inmunología , Interleucina-2/inmunología , Linfocitos T CD8-positivos/química , Proliferación Celular , Citomegalovirus/inmunología , VIH/inmunología , Sobrevivientes de VIH a Largo Plazo , Antígenos HLA-B/inmunología , Hepacivirus/inmunología , Humanos , Antígenos Comunes de Leucocito/análisis , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/análisis
16.
J Immunol ; 181(1): 546-56, 2008 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-18566421

RESUMEN

Acquisition of T cell responses during primary CMV infection in lung transplant recipients (LTRs) appear critical for host defense and allograft durability, with increased mortality in donor+/recipient- (D+R-) individuals. In 15 D+R- LTRs studied, acute primary CMV infection was characterized by viremia in the presence or absence of pneumonitis, with viral loads higher in the lung airways/allograft compared with the blood. A striking influx of CD8+ T cells into the lung airways/allograft was observed, with inversion of the CD4+:CD8+ T cell ratio. De novo CMV-specific CD8+ effector frequencies in response to pooled peptides of pp65 were strikingly higher in lung mononuclear cells compared with the PBMC and predominated over IE1-specific responses and CD4+ effector responses in both compartments. The frequencies of pp65-specific cytokine responses were significantly higher in lung mononuclear cells compared with PBMC and demonstrated marked contraction with long-term persistence of effector memory CD8+ T cells in the lung airways following primary infection. CMV-tetramer+CD8+ T cells from PBMC were CD45RA- during viremia and transitioned to CD45RA+ following resolution. In contrast, CMV-specific CD8+ effectors in the lung airways/allograft maintained a CD45RA- phenotype during transition from acute into chronic infection. Together, these data reveal differential CMV-specific CD8+ effector frequencies, immunodominance, and polyfunctional cytokine responses predominating in the lung airways/allograft compared with the blood during acute primary infection. Moreover, we show intercompartmental phenotypic differences in CMV-specific memory responses during the transition to chronic infection.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por Citomegalovirus/sangre , Infecciones por Citomegalovirus/inmunología , Citomegalovirus/inmunología , Trasplante de Pulmón/inmunología , Enfermedad Aguda , Adulto , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/citología , Enfermedad Crónica , Citocinas/biosíntesis , Citocinas/inmunología , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Citomegalovirus/virología , Femenino , Humanos , Memoria Inmunológica/inmunología , Antígenos Comunes de Leucocito/inmunología , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Fosfoproteínas/inmunología , Neumonía/inmunología , Trasplante Homólogo/inmunología , Proteínas de la Matriz Viral/inmunología , Viremia/inmunología
18.
J Immunol ; 180(1): 188-97, 2008 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18097019

RESUMEN

Evaluation of T cell responses to tumor- and pathogen-derived peptides in preclinical models is necessary to define the characteristics of efficacious peptide vaccines. We show in this study that vaccination with insect cells infected with baculoviruses expressing MHC class I linked to tumor peptide mimotopes results in expansion of functional peptide-specific CD8+ T cells that protect mice from tumor challenge. Specific peptide mimotopes selected from peptide-MHC libraries encoded by baculoviruses can be tested using this vaccine approach. Unlike other vaccine strategies, this vaccine has the following advantages: peptides that are difficult to solublize can be easily characterized, bona fide peptides without synthesis artifacts are presented, and additional adjuvants are not required to generate peptide-specific responses. Priming of antitumor responses occurs within 3 days of vaccination and is optimal 1 wk after a second injection. After vaccination, the Ag-specific T cell response is similar in animals primed with either soluble or membrane-bound Ag, and CD11c+ dendritic cells increase expression of maturation markers and stimulate proliferation of specific T cells ex vivo. Thus, the mechanism of Ag presentation induced by this vaccine is consistent with cross-priming by dendritic cells. This straightforward approach will facilitate future analyses of T cells elicited by peptide mimotopes.


Asunto(s)
Baculoviridae , Vacunas contra el Cáncer/inmunología , Antígenos H-2/inmunología , Insectos/inmunología , Neoplasias/inmunología , Neoplasias/prevención & control , Animales , Baculoviridae/genética , Antígeno CD11c/análisis , Linfocitos T CD8-positivos/inmunología , Vacunas contra el Cáncer/genética , Reactividad Cruzada , Células Dendríticas/inmunología , Antígenos H-2/genética , Antígeno de Histocompatibilidad H-2D , Insectos/citología , Insectos/virología , Complejo Mayor de Histocompatibilidad/inmunología , Ratones , Ratones Transgénicos , Péptidos/genética , Péptidos/inmunología , Vacunación
19.
Clin Infect Dis ; 36(4): E63-6, 2003 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-12567323

RESUMEN

Trichosporon species are an emerging cause of infection, particularly among transplant recipients. We report what we believe to be the first case of successful management of disseminated Trichosporon mucoides infection with orally administered fluconazole in a heart and kidney transplant recipient.


Asunto(s)
Antifúngicos/uso terapéutico , Fluconazol/uso terapéutico , Trasplante de Corazón , Trasplante de Riñón , Micosis/tratamiento farmacológico , Trichosporon/aislamiento & purificación , Administración Oral , Anciano , Humanos , Masculino , Micosis/microbiología , Resultado del Tratamiento
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