RESUMEN
Complete remission from recurrent EBV-positive lymphoma is not mandatory before HSCT to achieve long-term cure in a patient suffering from a recently described immunodeficiency affecting the T-cell coactivation molecule 4-1BB.
Asunto(s)
Ligando 4-1BB/deficiencia , Infecciones por Virus de Epstein-Barr/patología , Trasplante de Células Madre Hematopoyéticas , Linfoma de Células B/terapia , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/genética , Niño , Infecciones por Virus de Epstein-Barr/terapia , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Linfoma de Células B/patología , MasculinoRESUMEN
The CD137L-CD137 axis is a potent co-stimulatory immune checkpoint regulator that forms a bidirectional signaling pathway between the CD137 ligand (CD137L) and CD137 receptor to regulate immunological activities. This study investigated the potential involvement of the CD137L-CD137 axis on inflammasome-associated brain injury and neurological deficits in a mouse model of focal ischemic stroke. Cerebral ischemia was induced in male C57BL/6J wild-type (WT), CD137L-deficient (CD137L KO) and CD137-deficient (CD137 KO) mice by middle cerebral artery occlusion (MCAO; 60 min), followed by reperfusion (6 h and 24 h). Brain infarct volume and neurological deficit scores were significantly lower in both CD137L KO and CD137 KO mice compared to WT controls. Moreover, CD137L-deficient brains had significantly lower levels of the pyroptotic protein, NT-Gasdermin D, while CD137-deficient brains had significantly lower levels of the pro-apoptotic proteins, cleaved caspase-3, pyroptotic protein, NT-Gasdermin D, and of the secondary pyroptotic protein NT-Gasdermin E, following ischemic stroke. This protection by CD137L and CD137 deletion was associated with a significant decrease in inflammasome signaling. In conclusion, our data provide evidence for the first time that the CD137L-CD137 axis contributes to brain injury and neurological deficits by activating the inflammasome signaling pathway following ischemic stroke.
Asunto(s)
Ligando 4-1BB/fisiología , Infarto de la Arteria Cerebral Media/metabolismo , Inflamasomas/fisiología , Accidente Cerebrovascular Isquémico/metabolismo , Proteínas del Tejido Nervioso/fisiología , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/fisiología , Ligando 4-1BB/deficiencia , Alarminas/metabolismo , Animales , Apoptosis , Proteínas Reguladoras de la Apoptosis/metabolismo , Daño Encefálico Crónico/etiología , Infarto Cerebral/etiología , Infarto Cerebral/patología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Accidente Cerebrovascular Isquémico/complicaciones , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas de Unión a Fosfato/metabolismo , Receptores de Estrógenos/metabolismo , Daño por Reperfusión/metabolismo , Transducción de Señal/fisiología , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/deficienciaRESUMEN
Anti-tumor immune response and the prognosis of tumor are the results of competition between stimulatory and inhibitory checkpoints. Except for upregulating inhibitory checkpoints, lowering some immune accelerating molecules to convert an immunostimulatory microenvironment into an immunodormant one through "decelerating the accelerator" might be another effective immune escape pattern. 4-1BBL is a classical transmembrane costimulatory molecule involving in antitumor immune responses. In contrast, we demonstrated that 4-1BBL is predominantly localized in the nuclei of cancer cells in colon cancer specimens and is positively correlated with tumor size, lymph node metastasis, and a lower survival ratio. Furthermore, the nuclear localization of 4-1BBL was also ascertained in vitro. 4-1BBL knockout (KO) arrests the proliferation and impaired the migration and invasion ability of colon cancer cells in vitro and retarded tumor growth in vivo. 4-1BBL KO increased the accumulation of Gsk3ß in the nuclei of colon cancer cells and consequently decreased the expression of Wnt pathway target genes and thus alter tumor biological behavior. We hypothesized that unlike membrane-expressed 4-1BBL, which stimulates the 4-1BB signaling of antitumor cytotoxic T cells, the nuclear-localized 4-1BBL could facilitate the malignant behavior of colon cancer cells by circumventing antitumor signaling and driving some key oncotropic signal pathway in the nucleus. Nuclear-localized 4-1BBL might be an indicator of colon cancer malignancy and serve as a promising target of immunotherapy.
Asunto(s)
Ligando 4-1BB/metabolismo , Movimiento Celular , Núcleo Celular/metabolismo , Neoplasias del Colon/diagnóstico , Neoplasias del Colon/patología , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Ligando 4-1BB/biosíntesis , Ligando 4-1BB/deficiencia , Ligando 4-1BB/genética , Animales , Secuencia de Bases , Línea Celular Tumoral , Núcleo Celular/enzimología , Proliferación Celular , Estudios de Cohortes , Neoplasias del Colon/enzimología , Neoplasias del Colon/metabolismo , Modelos Animales de Enfermedad , Técnicas de Inactivación de Genes , Células HCT116 , Humanos , Ratones , Trasplante de Neoplasias , Pronóstico , Transporte de Proteínas , Análisis de SupervivenciaRESUMEN
The CD137-CD137 ligand (CD137L) costimulatory system is a critical immune checkpoint with pathophysiological implications in autoimmunity. In this study, we investigated the role of CD137L-mediated costimulation on renal, cutaneous and cerebral manifestations in lupus and the underlying immunological mechanism. Lupus-prone C57BL/6lpr-/- (B6.lpr) mice were crossed to C57BL/6.CD137L-/- mice to obtain CD137L-deficient B6.lpr [double knock out (DKO)] mice. We investigated the extent of survival, glomerulonephritis, skin lesions, cerebral demyelination, immune deviation and long-term synaptic plasticity among the two mouse groups. Cytokine levels, frequency of splenic leukocyte subsets and phenotypes were compared between DKO, B6.lpr and B6.WT mice. A 22 month observation of 226 DKO and 137 B6.lpr mice demonstrated significantly more frequent proliferative glomerulonephritis, larger skin lesions and shorter survival in DKO than in B6.lpr mice. Conversely, microglial activation and cerebral demyelination were less pronounced while long-term synaptic plasticity, was superior in DKO mice. Splenic Th17 cells were significantly higher in DKO than in B6.lpr and B6.WT mice while Th1 and Th2 cell frequencies were comparable between DKO and B6.lpr mice. IL-10 and IL-17 expression by T cells was not affected but there were fewer IL-10-producing myeloid (CD11b+) cells, and also lower serum IL-10 levels in DKO than in B6.lpr mice. The absence of CD137L causes an immune deviation toward Th17, fewer IL-10-producing CD11b+ cells and reduced serum IL-10 levels which potentially explain the more severe lupus in DKO mice while leading to reduced microglia activation, lesser cerebral damage and less severe neurological deficits.
Asunto(s)
Ligando 4-1BB/deficiencia , Encéfalo/inmunología , Riñón/inmunología , Nefritis Lúpica/inmunología , Piel/inmunología , Ligando 4-1BB/inmunología , Animales , Encéfalo/patología , Eliminación de Gen , Interleucina-10/genética , Interleucina-10/inmunología , Riñón/patología , Nefritis Lúpica/genética , Nefritis Lúpica/patología , Ratones , Ratones Noqueados , Piel/patología , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/patologíaRESUMEN
4-1BB signals are considered positive regulators of T cell responses against viruses and tumors, but recent studies suggest that they have more complex roles in modulating T cell responses. Although dual roles of 4-1BB signaling in T cell responses have been suggested, the underlying mechanisms are still not fully understood. In this study, we tested whether 4-1BB expression affected T cell responses differently when expressed in myeloid versus lymphoid cells in vivo. By assessing the proliferation of 4-1BB(+/+) and 4-1BB(-/-) T cells in lymphocyte-deficient RAG2(-/-) and RAG2(-/-)4-1BB(-/-) mice, we were able to compare the effects on T cell responses of 4-1BB expression on myeloid versus T cells. Surprisingly, adoptively transferred T cells were more responsive in tumor-bearing RAG2(-/-)4-1BB(-/-) mice than in RAG2(-/-) mice, and this enhanced T cell proliferation was further enhanced if the T cells were 4-1BB deficient. Dendritic cells (DCs) rather than NK or tissue cells were the myeloid lineage cells primarily responsible for the enhanced T cell proliferation. However, individual 4-1BB(-/-) DCs were less effective in T cell priming in vivo than 4-1BB(+/+) DCs; instead, more DCs in the secondary lymphoid organs of RAG2(-/-)4-1BB(-/-) mice appeared to induce the enhanced T cell proliferation by producing and transpresenting more IL-15. Therefore, we conclude that in vivo 4-1BB signaling of myeloid cells negatively regulates peripheral T cell responses by limiting the differentiation of DCs and their accumulation in secondary lymphoid organs.
Asunto(s)
Ligando 4-1BB/inmunología , Proliferación Celular , Interleucina-15/inmunología , Activación de Linfocitos/inmunología , Células Mieloides/inmunología , Linfocitos T/inmunología , Ligando 4-1BB/deficiencia , Traslado Adoptivo , Animales , Diferenciación Celular/inmunología , Células Dendríticas/citología , Células Dendríticas/inmunología , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Interleucina-15/biosíntesis , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Although the accumulation of highly-differentiated and granzyme B (GrB)-expressing CD8(+)CD28(-) T cells has been associated with aging, the mechanism for their enrichment and contribution to immune function remains poorly understood. Here we report a novel B-cell subset expressing 4-1BBL, which increases with age in humans, rhesus macaques, and mice, and with immune reconstitution after chemotherapy and autologous progenitor cell transplantation. These cells (termed 4BL cells) induce GrB(+)CD8(+) T cells by presenting endogenous antigens and using the 4-1BBL/4-1BB axis. We found that the 4BL cells increase antitumor responses in old mice, which may explain in part the paradox of retarded tumor growth in the elderly. 4BL cell accumulation and its capacity to evoke the generation of GrB(+)CD8(+) T cells can be eliminated by inducing reconstitution of B cells in old mice, suggesting that the age-associated skewed cellular immune responses are reversible. We propose that 4BL cells and the 4-1BBL signaling pathway are useful targets for improved effectiveness of natural antitumor defenses and therapeutic immune manipulations in the elderly.
Asunto(s)
Ligando 4-1BB/metabolismo , Envejecimiento/inmunología , Subgrupos de Linfocitos B/inmunología , Linfocitos T CD8-positivos/inmunología , Granzimas/metabolismo , Ligando 4-1BB/deficiencia , Ligando 4-1BB/genética , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/metabolismo , Envejecimiento/patología , Animales , Subgrupos de Linfocitos B/citología , Subgrupos de Linfocitos B/metabolismo , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/enzimología , Femenino , Humanos , Inmunidad Celular , Inmunidad Innata , Macaca mulatta , Masculino , Melanoma Experimental/inmunología , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Persona de Mediana Edad , Transducción de Señal , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismoRESUMEN
The role of the CD137-CD137 ligand (CD137L) signaling pathway in T cell co-stimulation has been well established. Dysregulated CD137 or CD137L stimulation can lead to pathological conditions such as inflammatory diseases or cancer. However, the contribution of CD137-CD137L interaction to the control of infectious diseases has not been extensively studied, with the few available reports focusing mainly on viral infections. Here we investigated the role of the CD137-CD137L interactions during Mycobacterium tuberculosis infection. Using CD137L-deficient mice, we found that absence of the CD137L-mediated signaling pathway during M. tuberculosis infection resulted in delayed activation of CD4(+) T cells in the draining lymph nodes. This finding was supported by an in vitro mixed lymphocyte reaction assay that revealed impaired priming of T cells by CD137L-deficient dendritic cells upon mycobacterial infection. In addition, greater numbers of CD4(+) T cells and antigen presenting cells were measured in the lungs of CD137L-deficient mice. Strikingly, the lung cytokine production profile was profoundly altered in M. tuberculosis-infected CD137L-deficient mice with lower levels of TNF-α, IL-12 and IL-6 and elevated concentrations of IL-17 compared to their wild type counterparts. However and surprisingly, these tangible immunological disorders translated only into a mild and transient increase in the bacterial loads and a higher number of granulomatous lesions with impaired architecture in the lungs of the CD137L-deficient infected mice. Together, while our data support the engagement of the CD137L signaling pathway during M. tuberculosis infection, they underscore the functional redundancy and robustness of the host defense arsenal deployed against mycobacterial infection.
Asunto(s)
Ligando 4-1BB/inmunología , Mycobacterium tuberculosis/inmunología , Transducción de Señal/inmunología , Tuberculosis/inmunología , Ligando 4-1BB/deficiencia , Ligando 4-1BB/genética , Animales , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/microbiología , Citocinas/inmunología , Citocinas/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Células Dendríticas/microbiología , Femenino , Citometría de Flujo , Interacciones Huésped-Patógeno/inmunología , Inmunohistoquímica , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/microbiología , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/microbiología , Activación de Linfocitos/inmunología , Prueba de Cultivo Mixto de Linfocitos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mycobacterium tuberculosis/fisiología , Transducción de Señal/genética , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Subgrupos de Linfocitos T/microbiología , Factores de Tiempo , Tuberculosis/genética , Tuberculosis/microbiología , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/inmunología , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismoRESUMEN
CD137 is a costimulatory molecule expressed on activated T cells. Its ligand, CD137L, is expressed on the surface of hematopoietic progenitor cells, and upon binding to CD137 induces reverse signaling into hematopoietic progenitor cells promoting their activation, proliferation and myeloid differentiation. Since aging is associated with an increasing number of myeloid cells we investigated the role of CD137 and CD137L on myelopoiesis during aging. Comparing 3 and 12 months old WT, CD137/ and CD137L/ mice we found significantly more granulocytes and monocytes in the bone marrow of older WT mice, while this agedependent increase was absent in CD137/ and CD137L/ mice. Instead, the bone marrow of 12 months old CD137/ and CD137L/ mice was characterized by an accumulation of hematopoietic progenitor cells, suggesting that the differentiation of hematopoietic progenitor cells became arrested in the absence of CD137L signaling. CD137L signaling is initiated by activated CD137expressing, CD4+ T cells. These data identify a novel molecular mechanisms underlying immune aging by demonstrating that CD137expressing CD4+ T cells in the bone marrow engage CD137L on hematopoietic progenitor cells, and that this CD137L signaling biases hematopoiesis towards myelopoiesis during aging.
Asunto(s)
Ligando 4-1BB/metabolismo , Envejecimiento/inmunología , Envejecimiento/patología , Ligando 4-1BB/deficiencia , Ligando 4-1BB/genética , Animales , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/inmunología , Diferenciación Celular/inmunología , Hematopoyesis/inmunología , Hematopoyesis/fisiología , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/inmunología , Ratones , Ratones Noqueados , Mielopoyesis/inmunología , Mielopoyesis/fisiología , Transducción de Señal/inmunología , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/deficiencia , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/genética , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismoRESUMEN
Immune complexes combining IL-2 with particular anti-IL-2 antibodies can be used to selectively expand regulatory T cells or memory T cells. Combining IL-2 with anti-IL-2 (Clone S4B6) greatly enhances the biological potency of IL-2 in vivo leading to selective expansion of CD8 memory T cells and NK cells compared with regulatory T cells. Here we show that in vivo administration of IL-2/anti-IL-2 mAb (IL-2/mAb) complexes induces 4-1BB expression on both adoptively transferred antigen-specific memory CD8 T cells as well as on endogenous memory phenotype cells. Remarkably, the accumulation of adoptively transferred memory CD8 T cells following in vivo IL-2/mAb-complex treatment was found to be dependent in part on the presence of 4-1BBL in the host. These effects were independent of IL-2-induced cell division, suggesting that 4-1BBL-induced survival signals contribute to IL-2/mAb-complex-induced T-cell accumulation in vivo.
Asunto(s)
Ligando 4-1BB/inmunología , Anticuerpos Monoclonales/farmacología , Linfocitos T CD8-positivos/efectos de los fármacos , Interleucina-2/farmacología , Ligando 4-1BB/deficiencia , Ligando 4-1BB/genética , Traslado Adoptivo , Animales , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Supervivencia Celular/inmunología , Citometría de Flujo , Memoria Inmunológica/inmunología , Interleucina-2/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/inmunología , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismoRESUMEN
Renal ischemia-reperfusion injury (IRI) after kidney transplantation is a major cause of delayed graft function. Even though IRI is recognized as a highly coordinated and specific process, the pathways and mechanisms through which the innate response is activated are poorly understood. In this study, we used a mouse model of acute kidney IRI to examine whether the interactions of costimulatory receptor CD137 and its ligand (CD137L) are involved in the early phase of acute kidney inflammation caused by IRI. We report here that the specific expressions of CD137 on natural killer cells and of CD137L on tubular epithelial cells (TECs) are required for acute kidney IRI. Reverse signaling through CD137L in TECs results in their production of the chemokine (C-X-C motif) receptor 2 ligands CXCL1 and CXCL2 and the subsequent induction of neutrophil recruitment, resulting in a cascade of proinflammatory events during kidney IRI. Our findings identify an innate pathogenic pathway for renal IRI involving the natural killer cell-TEC-neutrophil axis, whereby CD137-CD137L interactions provide the causal contribution of epithelial cell dysregulation to renal IRI. The CD137L reverse signaling pathway in epithelial cells therefore may represent a good target for blocking the initial stage of inflammatory diseases, including renal IRI.
Asunto(s)
Ligando 4-1BB/inmunología , Células Epiteliales/inmunología , Inflamación/patología , Túbulos Renales/inmunología , Túbulos Renales/patología , Células Asesinas Naturales/inmunología , Transducción de Señal/inmunología , Ligando 4-1BB/deficiencia , Traslado Adoptivo , Animales , Quimiocina CXCL1/biosíntesis , Quimiocina CXCL2/biosíntesis , Quimiotaxis , Células Epiteliales/trasplante , Inflamación/complicaciones , Inflamación/inmunología , Células Asesinas Naturales/trasplante , Ratones , Ratones Endogámicos C57BL , Neutrófilos/citología , Receptores Fc/inmunología , Daño por Reperfusión/complicaciones , Daño por Reperfusión/inmunología , Daño por Reperfusión/patologíaRESUMEN
Vaccines represent an attractive treatment modality for the management of cancer primarily because of their specificity and generation of immunologic memory important for controlling recurrences. However, the efficacy of therapeutic vaccines may require formulations that not only generate effective immune responses but also overcome immune evasion mechanisms employed by progressing tumor. Costimulatory molecules play critical roles in modulating innate, adaptive, and regulatory immunity and have potential to serve as effective immunomodulatory components of therapeutic vaccines. In this study, we tested the function of a novel soluble form of 4-1BB ligand (4-1BBL) costimulatory molecule in modulating innate, adaptive, and regulatory immunity and assessed its therapeutic efficacy in the HPV-16 E7-expressing TC-1 cervical cancer and survivin-expressing 3LL lung carcinoma mouse models. Vaccination with 4-1BBL activated dendritic cells and enhanced antigen uptake, generated CD8(+) T-cell effector/memory responses, and endowed T effector cells refractory to suppression by CD4(+)CD25(+)FoxP3(+) T regulatory cells. Immunization with 4-1BBL in combination with an E7 peptide or survivin protein resulted in eradication of TC-1 and 3LL tumors, respectively. 4-1BBL was more effective than TLR agonists LPS, MPL, and CpG and an agonistic 4-1BB antibody as a component of E7 peptide-based therapeutic vaccine for the generation of immune responses and eradication of TC-1 established tumors in the absence of detectable toxicity. Therapeutic efficacy was associated with reversal of tumor-mediated nonresponsiveness/anergy as well as establishment of long-term CD8(+) T-cell memory. Potent pleiotropic immunomodulatory activities combined with lack of toxicity highlight the potential of 4-1BBL molecule as an effective component of therapeutic cancer vaccines.
Asunto(s)
Ligando 4-1BB/uso terapéutico , Linfocitos T CD8-positivos/inmunología , Vacunas contra el Cáncer/inmunología , Células Dendríticas/inmunología , Ligando 4-1BB/deficiencia , Ligando 4-1BB/genética , Animales , Femenino , Humanos , Memoria Inmunológica/efectos de los fármacos , Proteínas Inhibidoras de la Apoptosis , Neoplasias Pulmonares/inmunología , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/inmunología , Activación de Linfocitos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Asociadas a Microtúbulos/uso terapéutico , Proteínas Represoras , Survivin , Neoplasias del Cuello Uterino/inmunologíaRESUMEN
A critical issue during severe respiratory infection is whether it is the virus or the host response that does the most damage. In this study, we show that endogenous 4-1BBL plays a critical role in protecting mice from severe effects of influenza disease. During mild respiratory influenza infection in which virus is rapidly cleared, the inducible costimulatory receptor 4-1BB is only transiently induced on lung T cells and 4-1BB ligand (4-1BBL) is completely dispensable for the initial CD8 T cell response and mouse survival. In contrast, during more severe respiratory influenza infection with prolonged viral load, 4-1BB expression on lung CD8 T cells is sustained, and 4-1BBL-deficient mice show decreased CD8 T cell accumulation in the lungs, decreased viral clearance, impaired lung function, and increased mortality. Transfer of an optimal number of naive Ag-specific T cells before infection protects wild-type but not 4-1BBL-deficient mice from an otherwise lethal dose of influenza virus. Transfer of T cells lacking the proapoptotic molecule Bim extends the lifespan of 4-1BBL-deficient mice by one to three days, suggesting that at least part of the role of 4-1BB/4-1BBL is to prolong effector cell survival long enough to clear virus. Intranasal delivery of 4-1BBL by recombinant adenovirus marginally improves survival of 4-1BBL-deficient mice at low dose, but exacerbates disease at high dose. These findings suggest a rationale for the evolutionary accumulation of inducible costimulatory molecules, thereby allowing the immune system to sustain the expression of molecules such as 4-1BB to a level commensurate with severity of infection.
Asunto(s)
Ligando 4-1BB/fisiología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Subtipo H3N2 del Virus de la Influenza A/inmunología , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/prevención & control , Ligando 4-1BB/biosíntesis , Ligando 4-1BB/deficiencia , Ligando 4-1BB/genética , Administración Intranasal , Animales , Epítopos de Linfocito T/análisis , Epítopos de Linfocito T/inmunología , Regulación de la Expresión Génica/inmunología , Epítopos Inmunodominantes/análisis , Epítopos Inmunodominantes/inmunología , Subtipo H1N1 del Virus de la Influenza A/patogenicidad , Subtipo H3N2 del Virus de la Influenza A/patogenicidad , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Infecciones por Orthomyxoviridae/mortalidad , Infecciones por Orthomyxoviridae/fisiopatología , Neumonía Viral/inmunología , Neumonía Viral/prevención & control , Neumonía Viral/virología , Pruebas de Función Respiratoria , Índice de Severidad de la Enfermedad , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/biosíntesis , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/genética , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/fisiología , VirulenciaRESUMEN
The stimulation of Toll-like receptors (TLRs) on macrophages triggers production of the cytokine tumor necrosis factor (TNF). TNF production occurs within 1 h of TLR stimulation and is sustained for 1 d. Here we document a function for the TNF family member 4-1BB ligand (4-1BBL) in sustaining TLR-induced TNF production. TLR signaling induced 4-1BBL, and 4-1BBL interacted with TLRs on the macrophage surface. The influence of 4-1BBL on TNF production was independent of its receptor (4-1BB) and did not require the adaptors MyD88 or TRIF. It did not influence TLR4-induced activation of transcription factor NF-kappaB (an early response) but was required for TLR4-induced activation of transcription factors CREB and C/EBP (a late event). Transient TLR4-MyD88 complexes appeared during the first hour after lipopolysaccharide stimulation, and TLR4-4-1BBL interactions were detected between 2 h and 8 h after lipopolysaccharide stimulation. Our results indicate that two different TLR4 complexes sequentially form and selectively control early and late TNF production.
Asunto(s)
Ligando 4-1BB/metabolismo , Macrófagos/metabolismo , Transducción de Señal , Receptores Toll-Like/metabolismo , Factores de Necrosis Tumoral/biosíntesis , Ligando 4-1BB/deficiencia , Ligando 4-1BB/genética , Animales , Línea Celular , Humanos , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 88 de Diferenciación Mieloide/metabolismo , Unión Proteica , Tasa de Supervivencia , Factores de TiempoRESUMEN
Our previous study has demonstrated that there is a significant delay of Balb/c cardiac allograft rejection in the C57BL/6 4-1BB-deficient knockout recipient. In this study, we examined the effect of combined blockade of the 4-1BB and CD28 costimulatory pathways on cardiac allograft rejection in the C57BL/6-->Balb/c model. A long-term cardiac allograft survival was induced in CD28/4-1BB- deficient mice (>100 days survival in 3 of 4 mice), which was comparable with CD28-deficient mice (>100 days survival in 2 of 5 mice; P<0.2026). There was no long-term cardiac allograft survival in either wild-type (WT) or 4-1BB-deficient mice, even though 4-1BB-deficient recipients showed a significant delay of cardiac allograft rejection than WT mice. An in vitro mixed leukocyte reaction (MLR) assay showed that 4-1BB-deficient and WT mouse T cells had a similar responsiveness to allostimulation, whereas CD28- and CD28/4-1BB-deficient mouse T cells had a defective responsiveness to allostimulation. Furthermore, 4-1BB-deficient mice showed a similar CTL but an elevated Ab response against alloantigens as compared to WT mice, and the alloimmune responses of 4-1BB-deficient mice were abrogated in the CD28-deficient background. Overall, these results indicate that the CD28 costimulatory pathway plays a major role in the alloimmune response and that 4-1BB signals are dependent upon CD28 signals.