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1.
Am J Transplant ; 12(1): 115-25, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21929643

RESUMEN

In murine models, T-cell costimulation blockade of the CD28:B7 and CD154:CD40 pathways synergistically promotes immune tolerance after transplantation. While CD28 blockade has been successfully translated to the clinic, translation of blockade of the CD154:CD40 pathway has been less successful, in large part due to thromboembolic complications associated with anti-CD154 antibodies. Translation of CD40 blockade has also been slow, in part due to the fact that synergy between CD40 blockade and CD28 blockade had not yet been demonstrated in either primate models or humans. Here we show that a novel, nondepleting CD40 monoclonal antibody, 3A8, can combine with combined CTLA4Ig and sirolimus in a well-established primate bone marrow chimerism-induction model. Prolonged engraftment required the presence of all three agents during maintenance therapy, and resulted in graft acceptance for the duration of immunosuppressive treatment, with rejection resulting upon immunosuppression withdrawal. Flow cytometric analysis revealed that upregulation of CD95 expression on both CD4+ and CD8+ T cells correlated with rejection, suggesting that CD95 may be a robust biomarker of graft loss. These results are the first to demonstrate prolonged chimerism in primates treated with CD28/mTOR blockade and nondepletional CD40 blockade, and support further investigation of combined costimulation blockade targeting the CD28 and CD40 pathways.


Asunto(s)
Antígenos CD40/antagonistas & inhibidores , Quimerismo , Inmunoconjugados/inmunología , Inmunosupresores/farmacología , Modelos Animales , Sirolimus/farmacología , Abatacept , Animales , Anticuerpos Monoclonales/inmunología , Antígenos CD28/inmunología , Antígenos CD40/inmunología , Citometría de Flujo , Trasplante de Células Madre Hematopoyéticas , Macaca mulatta
2.
Am J Transplant ; 12(8): 2079-87, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22845909

RESUMEN

The importance of CD40/CD154 costimulatory pathway blockade in immunosuppression strategies is well-documented. Efforts are currently focused on monoclonal antibodies specific for CD40 because of thromboembolic complications associated with monoclonal antibodies directed towards CD154. Here we present the rational development and characterization of a novel antagonistic monoclonal antibody to CD40. Rhesus macaques were treated with the recombinant anti-CD40 mAb, 2C10, or vehicle before immunization with keyhole limpet hemocyanin (KLH). Treatment with 2C10 successfully inhibited T cell-dependent antibody responses to KLH without significant peripheral B cell depletion. Subsequently, MHC-mismatched macaques underwent intraportal allogeneic islet transplantation and received basiliximab and sirolimus with or without 2C10. Islet graft survival was significantly prolonged in recipients receiving 2C10 (graft survival time 304, 296, 265, 163 days) compared to recipients receiving basiliximab and sirolimus alone (graft survival time 8, 8, 10 days). The survival advantage conferred by treatment with 2C10 provides further evidence for the importance of blockade of the CD40/CD154 pathway in preventing alloimmune responses. 2C10 is a particularly attractive candidate for translation given its favorable clinical profile.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos CD40/inmunología , Supervivencia de Injerto , Trasplante de Islotes Pancreáticos , Animales , Formación de Anticuerpos , Humanos , Macaca mulatta
3.
J Exp Med ; 186(10): 1725-35, 1997 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-9362532

RESUMEN

Topical exposure of mice to chemical allergens results in the migration of epidermal Langerhans cells (LCs) from the skin and their accumulation as immunostimulatory dendritic cells (DCs) in draining lymph nodes. Epidermal cell-derived cytokines have been implicated in the maturation and migration of LCs, but the adhesion molecules that regulate LC migration have not been studied. We hypothesized that integrin-mediated interactions with extracellular matrix components of the skin and lymph node may regulate LC/DC migration. We found that alpha 6 integrins and alpha 4 integrins were differentially expressed by epidermal LCs and lymph node DCs. A majority of LCs (70%) expressed the alpha 6 integrin subunit, whereas DCs did not express alpha 6 integrins. In contrast, the alpha 4 integrin subunit was expressed at high levels on DCs but at much lower levels on LCs. The anti-alpha 6 integrin antibody, GoH3, which blocks binding to laminin, completely prevented the spontaneous migration of LCs from skin explants in vitro and the rapid migration of LCs from mouse ear skin induced after intradermal administration of TNF-alpha in vivo. GoH3 also reduced the accumulation of DCs in draining lymph nodes by a maximum of 70% after topical administration of the chemical allergen oxazolone. LCs remaining in the epidermis in the presence of GoH3 adopted a rounded morphology, rather than the interdigitating appearance typical of LCs in naive skin, suggesting that the cells had detached from neighboring keratinocytes and withdrawn cellular processes in preparation for migration, but were unable to leave the epidermis. The anti-alpha 4 integrin antibody PS/2, which blocks binding to fibronectin, had no effect on LC migration from the epidermis either in vitro or in vivo, or on the accumulation of DCs in draining lymph nodes after oxazolone application. RGD-containing peptides were also without effect on LC migration from skin explants. These results identify an important role for alpha 6 integrins in the migration of LC from the epidermis to the draining lymph node by regulating access across the epidermal basement membrane. In contrast, alpha 4 integrins, or other integrin-dependent interactions with fibronectin that are mediated by the RGD recognition sequence, did not influence LC migration from the epidermis. In addition, alpha 4 integrins did not affect the accumulation of LCs as DCs in draining lymph nodes.


Asunto(s)
Antígenos CD/fisiología , Movimiento Celular/inmunología , Epidermis/inmunología , Integrinas/fisiología , Células de Langerhans/inmunología , Animales , Anticuerpos Bloqueadores/administración & dosificación , Anticuerpos Bloqueadores/farmacología , Anticuerpos Monoclonales/farmacología , Antígenos CD/biosíntesis , Antígenos CD/inmunología , Movimiento Celular/efectos de los fármacos , Células Dendríticas/metabolismo , Epidermis/efectos de los fármacos , Inmunoglobulina G/administración & dosificación , Integrina alfa4 , Integrina alfa6 , Integrinas/biosíntesis , Células de Langerhans/efectos de los fármacos , Células de Langerhans/metabolismo , Ratones , Ratones Endogámicos BALB C , Oligopéptidos/farmacología , Técnicas de Cultivo de Órganos , Ratas , Piel
4.
Health Psychol ; 20(1): 20-32, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11199062

RESUMEN

The authors tested effects of a 10-week group cognitive-behavioral stress management intervention among 100 women newly treated for Stage 0-II breast cancer. The intervention reduced prevalence of moderate depression (which remained relatively stable in the control condition) but did not affect other measures of emotional distress. The intervention also increased participants' reports that having breast cancer had made positive contributions to their lives, and it increased generalized optimism. Both remained significantly elevated at a 3-month follow-up of the intervention. Further analysis revealed that the intervention had its greatest impact on these 2 variables among women who were lowest in optimism at baseline. Discussion centers on the importance of examining positive responses to traumatic events--growth, appreciation of life, shift in priorities, and positive affect-as well as negative responses.


Asunto(s)
Terapia Conductista , Neoplasias de la Mama/psicología , Terapia Cognitivo-Conductual , Trastorno Depresivo/prevención & control , Adulto , Anciano , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/terapia , Trastorno Depresivo/epidemiología , Femenino , Humanos , Acontecimientos que Cambian la Vida , Persona de Mediana Edad , Prevalencia , Estrés Psicológico
7.
J Pers Assess ; 74(1): 63-87, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10779933

RESUMEN

Research on stress and its influence on health and well-being has flourished for several decades, examining as predictors such psychosocial variables as personality and coping. This work now often targets multiethnic samples. Because many potential participants lack facility in English, a need exists for translations of measures into other languages. We translated 6 instruments into Spanish and studied their characteristics. Of these, 3 were measures of personality qualities: the Life Orientation Test--Revised (Scheier, Carver, & Bridges, 1994), the Behavioral Inhibition/Behavioral Activation Scales (Carver & White, 1994), and the Measure of Body Apperception (Carver et al., 1998). The others were the Brief COPE (Carver, 1997), the Center for Epidemiological Studies--Depression Scale (Radloff, 1977), and an abbreviated version of the Profile of Mood States (McNair, Lorr, & Droppelman, 1971). Correlations between English and Spanish versions in bilingual samples were all above. 72, except for the COPE's Behavioral Disengagement scale. Alpha reliabilities of the Spanish versions were comparable to those of the English versions. Correlations among measures in a sample of cancer patients were similar across languages.


Asunto(s)
Afecto , Hispánicos o Latinos/psicología , Neoplasias/psicología , Inventario de Personalidad/normas , Personalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Comparación Transcultural , Femenino , Humanos , Masculino , Persona de Mediana Edad , Multilingüismo , Neoplasias/etnología , Escalas de Valoración Psiquiátrica/normas , Psicometría , Traducciones , Estados Unidos , Población Blanca/psicología
8.
Int Immunol ; 12(3): 241-51, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10700459

RESUMEN

Several cell adhesion molecules that mediate the binding of lymphocytes to high endothelial venules (HEV) from flowing blood have been identified but the regulation of lymphocyte migration across the HEV wall into the lymph node (LN) is far from understood. In this study we have used an in vitro model of lymphocyte migration across HEV, and analysed the roles of two integrins in the binding and transendothelial migration of T lymphocytes and T lymphoblasts. The adhesion of T lymphocytes to high endothelial cells (HEC) cultured from rat LN HEV differed from that of T lymphoblasts since the percentage of T lymphoblasts that adhered and transmigrated was higher and was not increased by IFN-gamma pretreatment of HEC. Antibodies to alpha(4) integrins, VCAM-1 or LFA-1 maximally inhibited T lymphocyte adhesion by 40-50%, whereas antibodies to ICAM-1 were less effective (<20% inhibition). The effects of alpha(4) integrin and LFA-1 antibodies were additive, giving >90% inhibition. T lymphocytes which adhered in the presence of LFA-1 antibody showed reduced levels of transmigration and, in the presence of alpha(4) integrin antibody, slightly increased transmigration. Antibodies to alpha(4) integrins, VCAM-1, LFA-1 or ICAM-1 had little effect on T lymphoblast adhesion (maxima of 10-30% inhibition) and T lymphoblasts transmigrated normally in the presence of either alpha(4) integrin or LFA-1 antibodies. However, the effects of alpha(4) integrin and LFA-1 antibodies on T lymphoblast adhesion were synergistic, giving >90% inhibition of adhesion. These results suggest that the majority of T lymphoblasts use either alpha(4) integrins or LFA-1 to bind and transmigrate HEV, and the roles of these integrins on activated T cells are overlapping and redundant. In contrast, either integrin supports half-maximal binding of unactivated T lymphocytes to the surface of HEV and LFA-1 makes a larger contribution than alpha(4) integrins to transendothelial migration.


Asunto(s)
Antígenos CD/fisiología , Endotelio Vascular/citología , Molécula 1 de Adhesión Intercelular/fisiología , Antígeno-1 Asociado a Función de Linfocito/fisiología , Linfocitos T/citología , Molécula 1 de Adhesión Celular Vascular/fisiología , Animales , Anticuerpos Monoclonales/farmacología , Antígenos CD/inmunología , Adhesión Celular/efectos de los fármacos , Células Cultivadas , Endotelio Vascular/metabolismo , Humanos , Integrina alfa4 , Molécula 1 de Adhesión Intercelular/inmunología , Ganglios Linfáticos/citología , Antígeno-1 Asociado a Función de Linfocito/inmunología , Ratas , Ratas Endogámicas , Proteínas Recombinantes de Fusión/metabolismo , Organismos Libres de Patógenos Específicos , Linfocitos T/metabolismo , Molécula 1 de Adhesión Celular Vascular/genética , Molécula 1 de Adhesión Celular Vascular/inmunología , Vénulas
9.
Psychosom Med ; 60(2): 168-74, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9560865

RESUMEN

OBJECTIVE: Several authors have suggested that patients adjust more poorly to breast cancer if they are heavily invested in body image as a source of their sense of self-worth. This prospective study examined this possibility, looking at two aspects of concern about body image as predictors of several indices of adjustment over the first postoperative year. METHODS: At diagnosis (and again a year later) 66 women with early stage breast cancer reported how much they valued a) a sense of body integrity (or intactness) and b) a good physical appearance. The day before surgery, a week afterward, and at 3-month, 6-month, and 12-month follow ups, they reported on their mood. At presurgery and at follow ups they also rated their attractiveness and sexual desirability and reported on frequency of sexual interaction. At follow-ups they also indicated how much their illness and treatment were interfering with social and recreational activities. RESULTS: Initial investment in appearance was related to distress across the postsurgical year. In contrast, investment in appearance made women more resilient against deterioration in their perceptions of attractiveness. Concern about body integrity did not strongly predict emotional distress, but it related to adverse impact on social and recreational activities in the follow-up period, to deterioration in feelings of sexual desirability, and to feelings of alienation from the self (feeling "not like yourself anymore"). CONCLUSIONS: Body image is often thought of in terms of physical appearance, but there is also a body image pertaining to integrity, wholeness, and normal functioning. People who are greatly concerned about either aspect of their body image are vulnerable to poorer psychosocial adjustment when confronting treatment for breast cancer. The poorer adjustment takes a different form, however, depending on the nature of the patient's body-image concern.


Asunto(s)
Adaptación Psicológica , Imagen Corporal , Neoplasias de la Mama/psicología , Ajuste Social , Adulto , Anciano , Actitud Frente a la Salud , Neoplasias de la Mama/terapia , Costo de Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Prospectivos , Análisis de Regresión , Autoimagen
10.
Nature ; 378(6554): 298-302, 1995 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-7477352

RESUMEN

The tyrosine kinase Syk (relative molecular mass 72,000), which is widely expressed in haematopoietic cells, becomes associated with and activated by engagement of the B-cell antigen receptor. Furthermore, it has been implicated in signalling through the receptors for interleukin-2 (IL-2), granulocyte colony-stimulating factor (G-CSF) and Fc, the T cell receptor, as well as through receptors for several platelet agonists. A homologous kinase, ZAP-70, is crucial in signalling through the T-cell receptor and in T-cell development. Using homologous recombination in embryonic stem cells, we created mice null for the syk gene which showed petechiae in utero and died shortly after birth. Irradiated mice reconstituted with Syk-deficient fetal liver showed a block in B-cell development at the pro-B to pre-B cell transition, consistent with a key role for Syk in pre-B-cell receptor signalling. Despite the production of small numbers of immature B cells, Syk-deficient radiation chimaeras failed to accumulate mature B cells, indicating a possible role for this protein in the production or maintenance of mature B cells. In addition, whereas the development of alpha beta T cells proceeded normally, Syk-deficient mice showed impaired development of thymocytes using the V gamma 3 variable region gene (V gamma 3+ thymocytes). Finally, we show that Syk is not required for signalling through the IL-2 and G-CSF receptors.


Asunto(s)
Linfocitos B/citología , Precursores Enzimáticos/fisiología , Proteínas Tirosina Quinasas/fisiología , Secuencia de Aminoácidos , Animales , Animales Recién Nacidos , Linfocitos B/patología , Linfocitos B/efectos de la radiación , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Línea Celular , Células Cultivadas , Quimera , Cruzamientos Genéticos , Precursores Enzimáticos/deficiencia , Precursores Enzimáticos/genética , Femenino , Péptidos y Proteínas de Señalización Intracelular , Hígado/citología , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Mutagénesis , Proteínas Tirosina Quinasas/deficiencia , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Púrpura/embriología , Quinasa Syk , Linfocitos T/citología , Proteína Tirosina Quinasa ZAP-70
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