RESUMEN
CD4+ CD25high FOXP3+ regulatory T cells (Tregs) are involved in graft-specific tolerance after solid organ transplantation. However, adoptive transfer of polyspecific Tregs alone is insufficient to prevent graft rejection even in rodent models, indicating that graft-specific Tregs are required. We developed a highly specific chimeric antigen receptor that recognizes the HLA molecule A*02 (referred to as A2-CAR). Transduction into natural regulatory T cells (nTregs) changes the specificity of the nTregs without alteration of their regulatory phenotype and epigenetic stability. Activation of nTregs via the A2-CAR induced proliferation and enhanced the suppressor function of modified nTregs. Compared with nTregs, A2-CAR Tregs exhibited superior control of strong allospecific immune responses in vitro and in humanized mouse models. A2-CAR Tregs completely prevented rejection of allogeneic target cells and tissues in immune reconstituted humanized mice in the absence of any immunosuppression. Therefore, these modified cells have great potential for incorporation into clinical trials of Treg-supported weaning after allogeneic transplantation.
Asunto(s)
Rechazo de Injerto/prevención & control , Antígeno HLA-A2/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Interleucina-2/inmunología , Linfocitos T Reguladores/inmunología , Aloinjertos , Animales , Rechazo de Injerto/inmunología , Supervivencia de Injerto/inmunología , Humanos , Ratones , Ratones Endogámicos NOD , Tolerancia al Trasplante/inmunologíaRESUMEN
The recognition and neutralization of tumour cells is one of the big challenges in immunity. The immune system has to recognize syngeneic tumour cells and has to be primed and respond in an adequate manner. Priming of a leukaemia-specific immune response is a crucial step in tumour immunology that can mislead to tumour tolerance either by T cell ignorance, deletion or Treg induction. To resemble the situation of acute lymphoblastic leukaemia (ALL) in patients, we used the murine BALB/c model with syngeneic BM185 tumour cells. We established a tumour cell line that expresses the neo-antigen ovalbumin (BM185-OVA/GFP) to allow the application of T cell receptor transgenic, antigen-specific CD4(+) T cells. Here, we demonstrate that effective anti-ALL immunity can be established by in vivo priming of CD4(+) T cells that is sufficient to differentiate into effector cells. Yet they failed to control tumour alone, but initiated a Th1 response. An efficient tumour clearance was dependent on both antigen-specific CD4(+) T cells and CD8(+) effector T cells from the endogenous repertoire. The tolerogeneic milieu was characterized by increased Tregs numbers and elevated IL-10 level. Tregs hamper effective antitumour immune response, but their depletion did not result in reduced tumour growth. In contrast, neutralization of IL-10 improved median mouse survival. Future therapies should focus on establishing a strong CD4+ T cells response, either by adjuvant or by adoptive transfer.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/trasplante , Inmunoterapia Adoptiva/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Animales , Células de la Médula Ósea/inmunología , Linfocitos T CD4-Positivos/metabolismo , Línea Celular Tumoral , Células Cultivadas , Células Dendríticas/inmunología , Femenino , Citometría de Flujo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/inmunología , Interferón gamma/sangre , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-10/sangre , Interleucina-10/inmunología , Interleucina-10/metabolismo , Interleucina-12/sangre , Interleucina-12/inmunología , Interleucina-12/metabolismo , Interleucina-2/sangre , Interleucina-2/inmunología , Interleucina-2/metabolismo , Estimación de Kaplan-Meier , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones SCID , Ovalbúmina/genética , Ovalbúmina/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Factores de TiempoRESUMEN
CD4(+)CD25highFOXP3(+) regulatory T cells (Tregs) can control allospecific immune responses in vitro and in titrated lymphopenic transplantation models. However, under non-lymphopenic conditions, as seen in patients with autoimmune diseases or after organ transplantation, polyspecific Tregs so far have been largely ineffective to control immune responses in animal models. Yet currently polyspecific CD4(+)CD25high Tregs are being tested in clinical trials. Donor materials are usually limited for the generation of donor-specific Tregs. Herein we have developed a method to produce large quantities of activated donor B cells by stimulation of donor peripheral blood mononuclear cells with 3T3 fibroblasts expressing CD40L. These activated donor B cells are potent stimulators of CD4(+)CD25high Tregs, which were expanded efficiently to inhibit an allo-MLR in donor-specific fashion. They were far more potent in inhibiting alloimmune responses in humanized mice compared with the polyspecific CD4(+)CD25high Tregs. Generation of donor-specific Tregs could be performed under good manufacturing practice conditions. Donor-reactive Tregs may be a valuable tool to control immune responses after transplantation a setting in which polyspecific Tregs have failed to date.
Asunto(s)
Linfocitos B/inmunología , Antígenos CD4/inmunología , Subunidad alfa del Receptor de Interleucina-2/inmunología , Linfocitos T Reguladores/inmunología , Células 3T3 , Animales , Proliferación Celular , Células Cultivadas , Metilación de ADN , RatonesRESUMEN
Acute cellular rejection (ACR) occurs frequently after liver transplantation and can usually be controlled. Triggering of allospecific immune responses and lack of immunoregulation are currently suggested as a cause of ACR, but there are no investigations of intrahepatic immune responses during ACR. Therefore we prospectively analyzed the intrahepatic T cell infiltration pattern in correlation to the severity of ACR in a cohort of patients with graft hepatitis (n = 151). While CD4(+) cells dominated the portal infiltrates in mild-moderate ACR, CD8(+) cells prevailed in severe ACR. Furthermore portal CD8(+) and not CD4(+) infiltration correlated with serum transaminases and with the likelihood of subsequent ACRs. Surprisingly, the rise of portal effector T cells density during ACR was surpassed by the increase in portal infiltration of regulatory T cells by a factor of two. Thus ACRs rather showed an increase and not a lack of regulation, as was suggested by analysis of peripheral blood mononuclear cells. Despite the pattern of enhanced immunoregulation, patients with severe ACR had a higher risk for subsequent rejections and showed a trend to a reduced survival. Thus, patients with severe rejections might need a modification of their immunosuppression to improve prognosis.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Rechazo de Injerto/inmunología , Leucocitos Mononucleares/inmunología , Trasplante de Hígado/inmunología , Linfocitos T Reguladores/inmunología , Enfermedad Aguda , Adulto , Anciano , Femenino , Humanos , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Trasplante HomólogoRESUMEN
CD83 is a marker molecule for mature dendritic cells (DCs) but is also substantially expressed on activated T cells in humans and mice. Its function is unknown, but CD83 knockout mice show an impaired thymic maturation of CD4-positive cells and soluble CD83 inhibits partially antigen-specific responses in vitro pointing to a role of CD83 in the immune system. Here we show that CD83-positive T cells produce strongly increased amounts of interferon-gamma and interleukin-2. In contrast, constitutive expression of CD83 on DCs alters neither the activation of DCs following addition of lipopolysaccharide nor the ability to present antigenic peptides. Thus, the expression of CD83 on T cells has direct functional consequences for tuning the activation threshold.
Asunto(s)
Inmunoglobulinas/inmunología , Activación de Linfocitos/inmunología , Glicoproteínas de Membrana/inmunología , Linfocitos T/inmunología , Animales , Antígenos CD , Diferenciación Celular/inmunología , Células Dendríticas/inmunología , Proteínas del Huevo/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Inmunoglobulinas/biosíntesis , Interferón gamma/biosíntesis , Interferón gamma/inmunología , Interleucina-2/biosíntesis , Interleucina-2/inmunología , Masculino , Glicoproteínas de Membrana/biosíntesis , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Transgénicos , Ovalbúmina/inmunología , Fragmentos de Péptidos , Linfocitos T/metabolismo , Antígeno CD83RESUMEN
1. The advantages of laparoscopic appendectomy over the traditional "open" method include decreased chance of wound infection, early ambulation and resumption of normal daily activities, decreased postoperative pain, improved diagnostic accuracy, better visualization of intra-abdominal anatomy, improved cosmetic results, and avoidance of "open" appendectomy if pathology is found during routine gynecologic laparoscopic surgery. 2. Single-puncture laparoscopy has several advantages over the multiple-puncture approach, including simplicity, expediency, lower cost, avoidance of potential complications associated with multiple punctures, improved cosmetic results, and flexibility to be converted into multiple-puncture laparoscopy or laparotomy when indicated. 3. Laparoscopy is expected to eventually replace laparotomy as the primary approach for most cases of diseases of the appendix. It is not suitable in cases of dense adhesions with distorted anatomy, malignancy, or severe pelvic peritonitis.
Asunto(s)
Apendicectomía/métodos , Laparoscopía/métodos , Apendicectomía/enfermería , Educación Continua en Enfermería , Humanos , Laparoscopía/enfermería , Enfermería de Quirófano/métodosRESUMEN
1. Laparoscopic hysterectomy obviates the need to create a traditional large abdominal incision. Through the laparoscope, surgical steps similar to those of a traditional abdominal hysterectomy are done prior to removal of the uterus via the vagina. 2. The dramatic improvement in postoperative recuperation in laparoscopic hysterectomy is the result of several factors: avoidance of laparotomy incision; minimal degree of traumatized and devitalized tissue as finer instrumentation is used; minimal use of suture material, reducing the chance of tissue reaction; and avoidance of postoperative bowel function compromise. 3. In the long run, laparoscopic hysterectomy will not replace all traditional abdominal and vaginal hysterectomies. Not all hysterectomies are candidates for laparoscopic surgery, such as patients with large pelvic masses or marked distortion of the anatomy due to various disease processes (ie, cancer).
Asunto(s)
Histerectomía/métodos , Laparoscopía/métodos , Femenino , Humanos , Histerectomía/enfermería , Laparoscopía/enfermería , Enfermería de Quirófano/métodosRESUMEN
1. The single puncture laparoscopy technique uses the umbilicus as the sole puncture site for the performance of surgical procedures. 2. The single puncture technique is simple, reduces complications, allows for faster recuperation and decreased operating time, is more cost-effective, and offers improved cosmetic results. 3. Each member of the surgical team must have all of the knowledge and skill related to each respective role. Major complications can only be avoided by being especially attentive to detail.