RESUMEN
Dendritic cells (DCs) are initiators of innate immunity and acquired immunity as cells linking these two bio-defence systems through the production of cytokines such as interferon-α (IFN-α) and interleukin-12 (IL-12). Nucleic acids such as DNA from damaged cells or pathogens are important activators not only for anti-microbial innate immune responses but also in the pathogenesis of IFN-related autoimmune diseases. Plasmacytoid DCs are regarded as the main effectors for the DNA-mediated innate immunity by possessing DNA-sensing toll-like receptor 9 (TLR9). We here found that double-stranded DNA (dsDNA) complexed with lipotransfectants triggered activation of human monocyte-derived DCs (moDCs), leading to the preferential production of IFN-α but not IL-12. This indicates that myeloid DCs also function as supportive effectors against the invasion of pathogenic microbes through the DNA-mediated activation in innate immunity. The dsDNA with lipotransfectants can be taken up by moDCs without co-localization of endosomal LAMP1 staining, and the dsDNA-mediated IFN-α production was not impaired by chloroquine. These findings indicate that moDC activation by dsDNA does not involve the endosomal TLR pathway. In contrast, single-stranded RNA (ssRNA) stimulated moDCs to secrete IL-12 but not IFN-α. This process was inhibited by chloroquine, suggesting an involvement of the TLR pathway in ssRNA-mediated moDC activation. As might be inferred from our findings, myeloid DCs may function as a traffic control between innate immunity via IFN-α production and acquired immunity via IL-12 production, depending on the type of nucleic acids. Our results provide a new insight into the biological action of myeloid DCs underlying the DNA-mediated activation of protective or pathogenic immunity.
Asunto(s)
ADN/inmunología , Células Dendríticas/inmunología , Interferón-alfa/metabolismo , Interleucina-12/metabolismo , Monocitos/inmunología , ARN/inmunología , Células Dendríticas/citología , Células Dendríticas/metabolismo , Humanos , Inmunidad Innata , Interferón-alfa/inmunología , Interleucina-12/inmunología , Monocitos/citología , Monocitos/metabolismo , Receptor Toll-Like 9/metabolismoRESUMEN
Engagement of the Fas receptor (CD95) initiates multiple signaling pathways that lead to apoptosis, such as the formation of death-inducing signaling complex (DISC), activation of caspase cascades, and the generation of the lipid messenger, ceramide. Sphingomyelin (SM) is a major component of lipid rafts, which are specialized structures that enhance the efficiency of membrane receptor signaling and are a main source of ceramide. However, the functions of SM in Fas-mediated apoptosis have yet to be clearly defined, as the responsible genes have not been identified. After cloning a gene responsible for SM synthesis, SMS1, we established SM synthase-defective WR19L cells transfected with the human Fas gene (WR/Fas-SM(-)), and cells that have been functionally restored by transfection with SMS1 (WR/Fas-SMS1). We show that expression of membrane SM enhances Fas-mediated apoptosis through increasing DISC formation, activation of caspases, efficient translocation of Fas into lipid rafts, and subsequent Fas clustering. Furthermore, WR/Fas-SMS1 cells, but not WR/Fas-SM(-) cells, showed a considerable increase in ceramide generation within lipid rafts upon Fas stimulation. These data suggest that a membrane SM is important for Fas clustering through aggregation of lipid rafts, leading to Fas-mediated apoptosis.
Asunto(s)
Apoptosis/fisiología , Ceramidas/metabolismo , Microdominios de Membrana/metabolismo , Transducción de Señal/fisiología , Esfingomielinas/metabolismo , Receptor fas/metabolismo , Animales , Apoptosis/genética , Caspasas/metabolismo , Línea Celular Tumoral , Eliminación de Gen , Humanos , Ratones , Transporte de Proteínas/genética , Transporte de Proteínas/fisiología , Transducción de Señal/genética , Transfección , Transferasas (Grupos de Otros Fosfatos Sustitutos)/genética , Transferasas (Grupos de Otros Fosfatos Sustitutos)/metabolismo , Receptor fas/genéticaRESUMEN
According to previous reports, the frequency of Epstein-Barr virus (EBV) positivity in diffuse large B-cell lymphoma is higher in East Asia (approximately 9%) than in Western countries. The presence of the EBV genome was examined in diffuse large B-cell lymphoma patients registered with the Osaka Lymphoma Study Group (OLSG) in Osaka, Japan, situated in East Asia. The EBV-positive rate was examined with in situ hybridization (ISH) in 484 immunocompetent diffuse large B-cell lymphoma patients registered with OLSG. The male-to-female ratio was 1.29, with ages ranging from 16 to 95 (median, 68) years. ISH with EBV-encoded small RNAs (EBER) probes revealed positive signals in the nuclei of tumor cells: the frequency of positively stained cells among all tumor cells was almost none in 458 cases, 5-10% in 5, 10-20% in 5, 20-50% in 11, and >50% in 5. When the frequency was >20% or >50%, the EBV-positive rate in the present series (3.3% or 1.0%) was rather similar to that reported in Western cases. Careful evaluation of patient backgrounds, including age distribution, type of lymphomas, exclusion of immunocompromised patients, and establishment of definite criteria for EBV positivity (>20%, >50%, or almost all tumor cells) are essential in comparing geographical differences.
Asunto(s)
Infecciones por Virus de Epstein-Barr/epidemiología , Herpesvirus Humano 4/aislamiento & purificación , Inmunocompetencia , Linfoma de Células B Grandes Difuso/epidemiología , Linfoma de Células B Grandes Difuso/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Japón/epidemiología , Linfoma de Células B Grandes Difuso/inmunología , Masculino , Persona de Mediana EdadRESUMEN
OECs (outgrowth endothelial cells), also known as late-EPCs (late-endothelial progenitor cells), have a high proliferation potential in addition to in vitro tube formation capability. In ischaemic animal models, injected OECs were integrated into regenerating blood vessels and improved neovascularization. Previous reports have demonstrated the expression of CXCL8 to be up-regulated in ischaemic tissues. It has also been documented that CXCL8 stimulates the angiogenic activity of mature ECs (endothelial cells). Therefore, it has been suggested that CXCL8 plays an important role in neovascularization in ischaemic tissues. However, it is still uncertain whether CXCL8 also stimulates the angiogenic activity of OECs. This study evaluated the effects of CXCL8 on the angiogenic activity of OECs in vitro. OECs were isolated from human UCB (umbilical cord blood)-derived mononuclear cells. Phenotypes of the OECs were assessed by flow cytometry, immunostaining, and real-time RT (reverse transcription)-PCR. The effects of CXCL8 on OECs were investigated by transwell migration assay and capillary tube formation assay on Matrigel. The OEC clones isolated from UCB expressed OEC phenotypes. In addition, CXCL8 receptors (CXCR1 and CXCR2) were expressed on these OEC clones. CXCL8 significantly stimulated the transwell migration and capillary tube formation of OECs. Neutralizing antibody against CXCR2, but not CXCR1, abolished a transwell migration of OECs induced by CXCL8, suggesting the involvement of CXCL8/CXCR2 axis in transwell migration. These results demonstrate that CXCL8 stimulates the angiogenic activity of UCB-derived OECs in vitro.
Asunto(s)
Células Endoteliales/metabolismo , Sangre Fetal/citología , Interleucina-8/farmacología , Neovascularización Fisiológica , Anticuerpos/inmunología , Movimiento Celular , Humanos , Fenotipo , Receptores de Interleucina-8A/metabolismo , Receptores de Interleucina-8B/metabolismoRESUMEN
OBJECTIVE: Statins, which are used as cholesterol-lowering agents, have pleiotropic immunomodulatory properties. Although beneficial effects of statins have been reported in autoimmune diseases, the mechanisms of these immunomodulatory effects are still poorly understood. Type I interferons (IFNs) and plasmacytoid dendritic cells (PDCs) represent key molecular and cellular pathogenic components in autoimmune diseases such as systemic lupus erythematosus (SLE). Therefore, PDCs may be a specific target of statins in therapeutic strategies against SLE. This study was undertaken to investigate the immunomodulatory mechanisms of statins that target the IFN response in PDCs. METHODS: We isolated human blood PDCs by flow cytometry and examined the effects of simvastatin and pitavastatin on PDC activation, IFNalpha production, and intracellular signaling. RESULTS: Statins inhibited IFNalpha production profoundly and tumor necrosis factor alpha production modestly in human PDCs in response to Toll-like receptor ligands. The inhibitory effect on IFNalpha production was reversed by geranylgeranyl pyrophosphate and was mimicked by either geranylgeranyl transferase inhibitor or Rho kinase inhibitor, suggesting that statins exert their inhibitory actions through geranylgeranylated Rho inactivation. Statins inhibited the expression of phosphorylated p38 MAPK and Akt, and the inhibitory effect on the IFN response was through the prevention of nuclear translocation of IFN regulatory factor 7. In addition, statins had an inhibitory effect on both IFNalpha production by PDCs from SLE patients and SLE serum-induced IFNalpha production. CONCLUSION: Our findings suggest a specific role of statins in controlling type I IFN production and a therapeutic potential in IFN-related autoimmune diseases such as SLE.
Asunto(s)
Células Dendríticas/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Interferón Tipo I/metabolismo , Células Cultivadas , Células Dendríticas/inmunología , Humanos , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/enzimología , Lupus Eritematoso Sistémico/inmunologíaRESUMEN
Dendritic cells (DCs) play a crucial role in the immune responses against infections by sensing microbial invasion through toll-like receptors (TLRs). In humans, two distinct DC subsets, CD11c(-) plasmacytoid DCs (PDCs) and CD11c(+) myeloid DCs (MDCs), have been identified and can respond to different TLR ligands, depending on the differential expression of cognate TLRs. In this study, we have examined the effect of TLR-7 ligands on human DC subsets. Both subsets expressed TLR-7 and could respond to TLR-7 ligands, which enhanced the survival of the subsets and upregulated the surface expression of costimulatory molecules such as CD40, CD80, and CD86. However, the cytokine induction pattern was distinct in that PDCs and MDCs produced interferon (IFN)-alpha and interleukin (IL)-12, respectively. In response to TLR-7 ligands, the Th1 cell supporting ability of both DC subsets was enhanced, depending on the cytokines the respective subsets produced. This study demonstrates that TLR-7 exerts its biological effect in a DC subset-specific manner.
Asunto(s)
Células Dendríticas/citología , Células Dendríticas/metabolismo , Proteínas de Drosophila , Interferón-alfa/metabolismo , Interleucina-12/metabolismo , Glicoproteínas de Membrana/agonistas , Glicoproteínas de Membrana/metabolismo , Receptores de Superficie Celular/agonistas , Receptores de Superficie Celular/metabolismo , Animales , Diferenciación Celular , Linaje de la Célula , Supervivencia Celular/efectos de los fármacos , Células Dendríticas/efectos de los fármacos , Humanos , Interferón-alfa/sangre , Interleucina-12/sangre , Ligandos , Glicoproteínas de Membrana/genética , Ratones , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Superficie Celular/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células TH1/citología , Receptor Toll-Like 7 , Receptores Toll-LikeRESUMEN
Although Bacillus Calmette-Guérin (BCG) has historically emerged as a potent adjuvant in cancer immunization through dendritic cell (DC) activation, the efficacy of its antitumor effect has been limited. Therefore, the strategy of adjuvant therapy using BCG needs to be improved by adding enhancers. Here we found that thymic stromal lymphopoietin (TSLP) acts as an enhancer for the BCG-mediated antitumor effect. While BCG-stimulated DCs induced CD8(+) T cell production of IFN-gamma without strong cell expansion, TSLP-stimulated DCs induced robust CD8(+) T cell expansion without high quantities of IFN-gamma production. Notably, DCs stimulated with both BCG and TSLP induced robust expansion of CD8(+) T cells that produced a large amount of IFN-gamma with a potent cytolytic activity related to granzyme B expression. Our data suggest that TSLP is a good adjuvant to enhance the BCG-mediated cytotoxic T cell effect through DC activation, and provide a functional basis for a novel strategy for antitumor immune-based therapy.
Asunto(s)
Adyuvantes Inmunológicos/farmacología , Linfocitos T CD8-positivos/efectos de los fármacos , Citocinas/farmacología , Células Dendríticas/efectos de los fármacos , Mycobacterium bovis/inmunología , Linfocitos T Citotóxicos/efectos de los fármacos , Adyuvantes Inmunológicos/metabolismo , Adulto , Ligando de CD40/farmacología , Linfocitos T CD8-positivos/fisiología , Citocinas/metabolismo , Células Dendríticas/fisiología , Regulación de la Expresión Génica , Humanos , Neutrófilos/inmunología , Receptores de Citocinas/metabolismo , Receptores de Interleucina-7/metabolismo , Linfocitos T Citotóxicos/fisiología , Linfopoyetina del Estroma TímicoRESUMEN
Understanding dendritic cell (DC) subset functions should lead to the development of novel types of vaccine. Here we characterized expression of XC chemokine receptor 1 (XCR1) and its ligand, XCL1. Murine XCR1 was the only chemokine receptor selectively expressed in CD8alpha(+) conventional DCs. XCL1 was constitutively expressed in NK cells, which contribute to serum XCL1 levels. NK and CD8(+) T cells increased XCL1 production upon activation. These expression patterns were conserved in human blood cells, including the BDCA3(+) DC subset. Thus, in human and mice, certain DC subsets should be chemotactic towards NK or activated CD8(+) T cells through XCR1.
Asunto(s)
Quimiocinas C/biosíntesis , Células Dendríticas/inmunología , Receptores de Quimiocina/biosíntesis , Receptores Acoplados a Proteínas G/biosíntesis , Animales , Antígenos CD8/inmunología , Linfocitos T CD8-positivos/inmunología , Línea Celular , Humanos , Células Asesinas Naturales/inmunología , Ligandos , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BLRESUMEN
Atopic dermatitis is a major allergic disease that develops through dysregulation of Th2-mediated inflammation. Although dendritic cells (DCs) have been thought to play a critical role in the upstream phase of the allergic cascade, conventional drugs such as steroids and chemical mediator antagonists target the effector cells or factors in allergic inflammation. Recently, it has been demonstrated that interaction between thymic stromal lymphopoietin (TSLP) and human DCs plays an essential role in evoking inflammatory Th2 responses in allergy through OX40 ligand expression on DCs. In this study, we provide evidence that R848, an imidazoquinoline compound, which is a TLR ligand and a strong Th1 response-inducing reagent, is a potent adjuvant for the alteration of the Th2-inducing potency of human DCs activated by TSLP (TSLP-DCs). R848 inhibited the inflammatory Th2-inducing capacity of TSLP-DCs and redirected them to possessing an IL-10 and IFN-gamma-producing regulatory Th1-inducing capacity. This functional alteration depended on both repression of OX40 ligand expression and induction of IL-12 production from DCs by the addition of R848. Additionally, R848 had the ability to inhibit the TSLP-mediated expansion and maintenance of the Th2 memory response. These findings suggest that imidazoquinoline may be a useful in the treatment of allergic diseases that are triggered by TSLP.
Asunto(s)
Adyuvantes Inmunológicos/farmacología , Citocinas/inmunología , Células Dendríticas/inmunología , Dermatitis Atópica/tratamiento farmacológico , Imidazoles/farmacología , Células Th2/inmunología , Adyuvantes Inmunológicos/uso terapéutico , Células Cultivadas , Dermatitis Atópica/inmunología , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/inmunología , Humanos , Imidazoles/uso terapéutico , Inflamación/tratamiento farmacológico , Inflamación/inmunología , Interferón gamma/inmunología , Interleucina-10/inmunología , Interleucina-12/inmunología , Ligando OX40/inmunología , Esteroides/uso terapéutico , Linfopoyetina del Estroma TímicoRESUMEN
ABCG2 is a transporter preferentially expressed in a primitive subpopulation of cells and recently reported as a surviving factor for trophoblasts. To date, manner of ABCG2 expression in lymphoid tissues is not known. Immunohistochemically, strong ABCG2 expression was found in a small proportion of plasma cells mainly located in the interfollicular space of lymphoid tissues. The number of ABCG2-high plasma cells increased in interleukin-6- (IL-6) rich lesions, such as Castleman's disease of plasma cell type. Plasma cells are subjected to endoplasmic reticulum (ER) stress when excess proteins are synthesized, and IL-6 stimulates protein synthesis. Therefore, the effect of IL-6 and ER stress on ABCG2 expression in plasma cells was examined. The expression level of ABCG2 increased by treatment with either IL-6 or ER stress inducers, and further increased with both. The promoter analysis revealed that the effect of IL-6 and ER stress inducers was mediated through the site overlapping XBP-1 and HIF-1 binding sequences. Knocked-down of ABCG2 by siRNA or ABCG2 inhibitor reduced plasma cell viability under ER stress. These suggest that ABCG2 is a surviving factor for plasma cells. To our knowledge, this is the first study reporting the effect of ER stress on ABCG2 expression.
Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Retículo Endoplásmico/metabolismo , Interleucina-6/metabolismo , Proteínas de Neoplasias/metabolismo , Células Plasmáticas/metabolismo , Estrés Fisiológico , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/genética , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Línea Celular , Metilación de ADN/efectos de los fármacos , Expresión Génica , Humanos , Inmunohistoquímica , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Linfoma/metabolismo , Proteínas de Neoplasias/genética , Tonsila Palatina/metabolismo , Tonsila Palatina/patología , Regiones Promotoras Genéticas , Tapsigargina/farmacología , Tunicamicina/farmacologíaRESUMEN
Allergic diseases such as atopic dermatitis and asthma develop as a consequence of dysregulated T(h)2 responses. Recently, it has been demonstrated that interaction between dendritic cells (DCs) and thymic stromal lymphopoietin (TSLP), an IL-7-like cytokine, is essential for evoking T(h)2 responses in allergy. In this study, we investigated whether Mycobacterium bovis Bacillus Calmette-Guérin (BCG), a strong T(h)1 response-inducing adjuvant, can alter the function of DCs activated by TSLP (TSLP-DCs). We demonstrated that BCG redirects TSLP-DCs away from inducing inflammatory T(h)2 cells that produce IL-4, IL-5, IL-13 and tumor necrosis factor (TNF)-alpha and toward regulatory T(h)1 cells that produce IFN-gamma and IL-10. We also demonstrated that this functional alteration of TSLP-DCs by BCG depended on both production of IL-12 from DCs and down-regulation of OX40 ligand, a member of the TNF family, on DCs. These findings suggest that BCG might be a useful adjuvant for the treatment of allergic diseases that are triggered by TSLP.
Asunto(s)
Vacuna BCG/inmunología , Citocinas/inmunología , Células Dendríticas/inmunología , Infecciones por Mycobacterium/inmunología , Mycobacterium bovis , Células Th2/inmunología , Vacuna BCG/uso terapéutico , Diferenciación Celular/inmunología , Citocinas/metabolismo , Células Dendríticas/metabolismo , Células Dendríticas/microbiología , Humanos , Hipersensibilidad/inmunología , Hipersensibilidad/terapia , Terapia de Inmunosupresión , Inmunoterapia , Activación de Linfocitos/inmunología , Infecciones por Mycobacterium/prevención & control , Ligando OX40/antagonistas & inhibidores , Células TH1/inmunología , Células TH1/metabolismo , Células TH1/microbiología , Células Th2/metabolismo , Células Th2/microbiología , Linfopoyetina del Estroma TímicoRESUMEN
A 28-year-old man had a 1-year history of hemoptysis. Consequently, he underwent a medical examination. A right pleural effusion, left hydropneumothorax, and multiple pulmonary nodular shadows were found on chest radiography. During a detailed interview, he reported that the hemoptysis began after eating "kejang" (a raw crab preparation) with a friend a year previously. His peripheral blood eosinophil count and serum IgE level were elevated. In addition, ova were detected in the sputum and bilateral pleural effusion. Morphological examination of the ova and immunoserological examination led to the diagnosis of Paragonimus westermani infection. The pleural effusion could be partially drained, and his symptoms and radiographic results showed improvement after treatment with Praziquantel administered at a dose of 75 mg/(kg x day) for 3 days. After one month, he and his friend ate seasoned raw crabs, Paragonimus was diagnosed in his friend. This case suggests that on encountering a paragonimus infection, everyone who ate food prepared in the same kitchen should be contacted because of possible infection with paragonimus.
Asunto(s)
Paragonimiasis/parasitología , Paragonimus westermani/aislamiento & purificación , Derrame Pleural/parasitología , Esputo/parasitología , Adulto , Animales , Culinaria , Humanos , MasculinoRESUMEN
The majority of cases of intravascular lymphomatosis (IVL) is derived from B cells. However, IVL may also arise from T cells, or more rarely NK cells. The clinicopathological findings in six cases of NK-cell IVL (NK-IVL), including one new case, were summarised and compared with B-cell IVL (B-IVL) and T-cell IVL (T-IVL). Earlier onset of disease and female predominance were found in NK-IVL. NK-IVL was typically Epstein-Barr virus (EBV)-positive, whereas EBV was rarely detected in B-IVL. Cutaneous manifestations were common in NK-IVL with constant EBV infection. B-IVL showed a more favourable prognosis than T- or NK-IVL. Irrespective of immunophenotype, however, IVL showed a less favourable prognosis than ordinary lymphomas within the same immunophenotype. In summary, IVL of the B-, T- and NK-cell phenotypes is clinicopathologically distinct and shows similarities to their more common counterparts, i.e. diffuse large B-cell lymphoma, peripheral T-cell lymphoma, unspecified and extranodal NK/T-cell lymphoma, nasal type.
Asunto(s)
Células Asesinas Naturales/patología , Linfoma no Hodgkin/patología , Neoplasias Vasculares/patología , Adulto , Anciano , Antineoplásicos/uso terapéutico , Femenino , Humanos , Linfoma de Células B , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/virología , Linfoma de Células T , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Neoplasias Vasculares/tratamiento farmacológico , Neoplasias Vasculares/virologíaRESUMEN
A recent report revealed that a large population of Hodgkin's lymphoma-infiltrating lymphocytes (HLILs) consisted of regulatory T cells. In this study, we cocultured CD4+ naive T cells with KM-H2, which was established as a Hodgkin's Reed-Sternberg cell line, to clarify their ability to induce CD25+ Forkhead box P3+ (Foxp3+) T cells. The characteristic analyses of T cells cocultured with KM-H2 revealed the presence of CD4+CD25+ T cells. They expressed CTLA-4, glucocorticoid-induced TNFR family-related gene, and Foxp3 and could produce large amounts of IL-10. Conversely, KM-H2 also generated CD4+ CTLs, which expressed Granzyme B and T cell intracellular antigen-1 in addition to Foxp3+ T cells. They exhibit a strong cytotoxic effect against the parental KM-H2. In conclusion, KM-H2 promotes a bidirectional differentiation of CD4+ naive T cells toward Foxp3+ T cells and CD4+ CTLs. In addition to KM-H2, several cell lines that exhibit the APC function were able to generate Foxp3+ T cells and CD4+ CTLs. Conversely, the APC nonfunctioning cell lines examined did not induce both types of cells. Our findings suggest that the APC function of tumor cells is essential for the differentiation of CD4+ naive T cells into CD25+Foxp3+ T cells and CD4+ CTLs and at least partly explains the predominance of CD25+Foxp3+ T cells in HLILs and their contribution to a better prognosis. Therefore, in APC-functioning tumors, including classical Hodgkin lymphomas, which generate Foxp3+ T cells and CD4+ CTLs, these T cell repertories play a beneficial role synergistically in disease stability.
Asunto(s)
Linfocitos T CD4-Positivos/citología , Diferenciación Celular/fisiología , Factores de Transcripción Forkhead/metabolismo , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Células de Reed-Sternberg/fisiología , Linfocitos T Citotóxicos/citología , Linfocitos T CD4-Positivos/metabolismo , Proliferación Celular , Células Cultivadas , Regulación de la Expresión Génica , Humanos , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Linfocitos T Citotóxicos/metabolismo , Transducción GenéticaRESUMEN
We measured and compared the levels of microparticles, chemokines, cell adhesion molecules and platelet activation markers with a view to developing a better understanding of their potential contributions to the pathophysiology of progressive systemic sclerosis (PSS, scleroderma). The concentrations of all the factors in PSS patients were significantly higher than those in normal subjects. PSS patients were divided to two groups by whether they have interstitial pneumonia (IP) or not. There were no differences in the levels of soluble(s) VCAM-1, sICAM-1, sE-selectin and IL-8 between the two groups. However, there were significant between-group differences in the levels of sP-selectin, sCD40L, ENA-78, RANTES (regulated on activation normally T-cell expressed and secreted), platelet-derived microparticles (PDMPs), monocyte-derived microparticle (MDMPs) and KL-6. The level of tissue factor expression on monocytes by A23187 stimulation in PSS patients was found to be similar to that in healthy controls. Although PDMP did not induce the expression of tissue factor on monocytic cell line (THP-1) directly, the recombinant sCD40 ligand-induced expression of tissue factor on THP-1 and generation of MDMP from this cell line were enhanced by the addition of PDMPs. Our findings suggested that elevated levels of PDMPs and MDMPs may be interpreted as a sign of vascular complications in PSS patients, particularly those complicated with IP, offering a new treatment strategy in these patients.
Asunto(s)
Plaquetas/metabolismo , Enfermedades Pulmonares Intersticiales/complicaciones , Enfermedades Pulmonares Intersticiales/fisiopatología , Monocitos/metabolismo , Esclerodermia Difusa/complicaciones , Esclerodermia Difusa/fisiopatología , Adulto , Anciano , Biomarcadores/metabolismo , Plaquetas/química , Moléculas de Adhesión Celular/metabolismo , Línea Celular , Citocinas/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monocitos/química , Activación Plaquetaria/fisiología , Tromboplastina/metabolismoRESUMEN
Pneumomediastinum is a rare complication of dermatomyositis (DM) and Polymiositis (PM). We report here three cases of PM/DM who developed pneumomediastinum. First case was 61 years old woman with amyopathic dermatomyositis (aDM). Her aDM was complicated with skin ulceration due to vasculopathy, but complicated interstitial pneumonia was not severe. She developed subcutaneous emphysema and pneumomediastinum. Second case was 57 years old woman with DM, who had intractable skin phenomena and mild interstitial pneumonia. The patient became subcutaneous emphysema and pneumomediastinum following severe vasculopathy of skin. The last case was 63 years old man with PM. His PM was complicated with interstitial pneumonia. He had intractable respiratory symptom. Ten years later, he became subcutaneous emphysema and pneumomediastinum following pneumothorax. First and second cases suggest that their pneumomediastinum were due to vasculopathy. On the other hand, pneumomediastinum of the last patient seemed to be associated with interstitial pneumonia and steroid.
Asunto(s)
Dermatomiositis/complicaciones , Enfisema Mediastínico/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Proteinase-activated receptors (PARs; PAR1-4) that can be activated by serine proteinases such as thrombin and neutrophil catepsin G are known to contribute to the pathogenesis of various pulmonary diseases including fibrosis. Among these PARs, especially PAR4, a newly identified subtype, is highly expressed in the lung. Here, we examined whether PAR4 stimulation plays a role in the formation of fibrotic response in the lung, through alveolar epithelial-mesenchymal transition (EMT) which contributes to the increase in myofibroblast population. METHODS: EMT was assessed by measuring the changes in each specific cell markers, E-cadherin for epithelial cell, alpha-smooth muscle actin (alpha-SMA) for myofibroblast, using primary cultured mouse alveolar epithelial cells and human lung carcinoma-derived alveolar epithelial cell line (A549 cells). RESULTS: Stimulation of PAR with thrombin (1 U/ml) or a synthetic PAR4 agonist peptide (AYPGKF-NH2, 100 muM) for 72 h induced morphological changes from cobblestone-like structure to elongated shape in primary cultured alveolar epithelial cells and A549 cells. In immunocytochemical analyses of these cells, such PAR4 stimulation decreased E-cadherin-like immunoreactivity and increased alpha-SMA-like immunoreactivity, as observed with a typical EMT-inducer, tumor growth factor-beta (TGF-beta). Western blot analyses of PAR4-stimulated A549 cells also showed similar changes in expression of these EMT-related marker proteins. Such PAR4-mediated changes were attenuated by inhibitors of epidermal growth factor receptor (EGFR) kinase and Src. PAR4-mediated morphological changes in primary cultured alveolar epithelial cells were reduced in the presence of these inhibitors. PAR4 stimulation increased tyrosine phosphorylated EGFR or tyrosine phosphorylated Src level in A549 cells, and the former response being inhibited by Src inhibitor. CONCLUSION: PAR4 stimulation of alveolar epithelial cells induced epithelial-mesenchymal transition (EMT) as monitored by cell shapes, and epithelial or myofibroblast marker at least partly through EGFR transactivation via receptor-linked Src activation.
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Alveolos Pulmonares/metabolismo , Alveolos Pulmonares/patología , Receptores de Trombina/metabolismo , Actinas/metabolismo , Animales , Western Blotting , Cadherinas/metabolismo , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Células Epiteliales/patología , Receptores ErbB/metabolismo , Fibroblastos/patología , Fibrosis , Humanos , Inmunohistoquímica , Mesodermo/patología , Ratones , Ratones Endogámicos C57BL , Músculo Liso/metabolismo , Músculo Liso/patología , Oligopéptidos/farmacología , Fenotipo , Fosforilación , Receptores de Trombina/agonistas , Trombina/farmacología , Factores de Tiempo , Tirosina/metabolismo , Familia-src Quinasas/metabolismoRESUMEN
Protease-activated receptor (PAR)-4 is a recently identified low-affinity thrombin receptor that plays a pathophysiological role in many types of tissues including the lung. Here, we showed for the first time that PAR4 mRNA and protein are expressed on primary cultured mouse lung alveolar epithelial cells by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunocytochemical analyses. In a fura 2-AM-loaded single epithelial cell, stimulation with thrombin (1 U/ml) and a PAR4 agonist peptide (AYPGKF-NH(2), 1-100 microM) increased intracellular Ca(2+) concentration ([Ca(2+)](i)), which consisted of an initial peak phase followed by a slowly decaying delayed phase, while a PAR1 agonist peptide, TFLLR-NH(2) (1-100 microM), induced a transient increase in [Ca(2+)](i). AYPGKF-NH(2) (10 microM)-induced [Ca(2+)](i) response was attenuated by a PAR4 antagonist peptide (tcY-NH(2)), a phospholipase C inhibitor, U-73122 (1-10 microM) or a Ca(2+)-ATPase inhibitor, thapsigargin (1 microM). Removal of extracellular Ca(2+) or an inhibitor of store-operated Ca(2+) entry, trans-resveratrol (1 microM) shortened the time to shut off the Ca(2+) response without any significant effects on the magnitude of the peak [Ca(2+)](i). Thus, stimulation of PAR4 appeared to mobilize Ca(2+) from intracellular stores in the initial peak response and to enhance Ca(2+) entry through the store depletion-operated pathway in the delayed phase. The latter mechanism probably contributed to the longer responsiveness of PAR4 stimulation.
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Señalización del Calcio/fisiología , Células Epiteliales/metabolismo , Alveolos Pulmonares/metabolismo , Receptores de Trombina/metabolismo , Animales , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Estrenos/farmacología , Expresión Génica/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Oligopéptidos/farmacología , Alveolos Pulmonares/efectos de los fármacos , Alveolos Pulmonares/patología , Pirrolidinonas/farmacología , ARN Mensajero/metabolismo , Receptor PAR-1/agonistas , Receptor PAR-1/genética , Receptor PAR-1/metabolismo , Receptores de Trombina/agonistas , Receptores de Trombina/genética , Resveratrol , Estilbenos/farmacología , Tapsigargina/farmacología , Trombina/farmacologíaRESUMEN
This study used a small-sized collagen bead column system to investigate platelet functions under high shear stress in 28 patients with effort angina and 15 healthy controls. Soluble P-selectin and soluble L-selectin were also evaluated. Patients underwent stent insertion, followed by treatment with aspirin (100 mg/day) and ticlopidine (200 mg/day). High-shear-dependent platelet function was measured using small-sized collagen beads. The retention rate of platelets from patients with angina was higher than that in healthy controls (10.9% +/- 3.9% versus 5.6% +/- 1.7%, P < .01). Soluble P-selectin and soluble L-selectin levels of patients with angina significantly increased after passage through the columns. Levels of soluble P-selectin and L-selectin in healthy controls did not exhibit significant changes with passage through the columns. These results suggested that high shear stress caused abnormal activation of leukocytes or adhesive proteins in patients with effort angina, and ticlopidine failed to suppress hyperaggregability of platelets in these patients.
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Angina de Pecho/sangre , Plaquetas/fisiología , Leucocitos/fisiología , Pruebas de Función Plaquetaria/métodos , Anciano , Angina de Pecho/tratamiento farmacológico , Angina de Pecho/terapia , Aspirina/uso terapéutico , Plaquetas/efectos de los fármacos , Estudios de Casos y Controles , Colágeno , Femenino , Hemorreología , Humanos , Técnicas In Vitro , Selectina L/sangre , Leucocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Selectina-P/sangre , Tamaño de la Partícula , Inhibidores de Agregación Plaquetaria/uso terapéutico , Solubilidad , Stents , Ticlopidina/uso terapéuticoRESUMEN
A 69-year-old man was admitted to our hospital with fever and right neck lymphadenopathy. A neck lymph node biopsy was performed. In the specimens, immunoblasts were present with an admixture of small T lymphocytes and macrophagocytes. Immunohistochemcal staining of immunoblasts was positive for CD20, CD30 and EBER. Epstein-Barr virus (EBV) serology showed elevated IgG antibody to VCA, and EBV DNA was detected in the peripheral blood. Since he showed latency II without immunodeficiency disease, we diagnosed age-related EBV-associated B-cell lymphoproliferative disorder (EBV-LPD) as a result of aging and EBV infection. He was treated with 6 courses of the CHOP regimen plus rituximab, and achieved complete remission. EBV-DNA became undetectable at remission. In age-related EBV-LPD, there is some possibility that EBV-DNA in the peripheral blood is valuable as a tumor biomarker.