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71.
We previously found that a Salmonella typhimurium vector engineered to secrete soluble tumor antigen induces CD4(+) T cells resistant to CD4(+)CD25(+) regulatory T cells (Treg) and that glucocorticoid-induced tumor necrosis factor receptor family-related gene (GITR) signal is involved in the development of this resistance. In this study, we address the potential of incorporating GITR ligand (GITRL) as a way to augment the immunogenicity of cancer vaccines. BALB/c mice were immunized by gene gun with plasmids encoding the mutated extracellular signal-regulated kinase 2 (mERK) with or without plasmids encoding mouse GITRL. Coadministration with GITRL during primary and secondary immunization enhanced the induction of mERK-specific CD8(+) T cells. Antibody depletion and minigene analysis suggested that GITRL directly activated CTL epitope-specific CD8(+) T cells independently of CD4(+) T cells. Immunization with plasmids encoding a CTL epitope and GITRL resulted in strong tumor inhibition in a CD8(+) T cell-dependent manner. Furthermore, CTL epitope-specific CD8(+) T cells induced by immunization with plasmids encoding CTL epitope coadministered with GITRL were refractory to suppression by CD4(+)CD25(+) Tregs compared with CD8(+) T cells induced without GITR signaling. We propose that coadministration of GITR signaling agents with tumor antigens constitutes a promising novel strategy for cancer vaccine development.  相似文献   
72.
De novo CD5+ diffuse large B-cell lymphoma (CD5+ DLBCL) is known to have phenotypically and genotypically different characteristics than CD5- DLBCL and mantle cell lymphoma (MCL). To further characterize CD5+ DLBCL, 109 patients with CD5+ DLBCL were reviewed, and the results were compared with those of 384 CD5- DLBCL and 128 cyclin D1+ MCL patients. Patients with CD5+ DLBCL showed a higher age distribution (median, 66 years; P =.0083) and a female predominance (male-female ratio, 49:60, P =.011) compared with those with CD5- DLBCL. CD5+ DLBCL was more closely associated with many aggressive clinical features or parameters than CD5- DLBCL: 69% older than 60 years (P =.039), 34% with performance status greater than 1 (P =.0016), 69% with serum lactate dehydrogenase level higher than normal (P <.0001), 62% with stage III/IV disease at diagnosis (P =.0023), 35% with more than one extranodal site (P =.023), and 40% with B symptoms (P =.0031). The overall International Prognostic Index score was thus significantly higher for the patients with CD5+ DLBCL than for those with CD5- DLBCL (P =.00005). The most frequent site of extranodal involvement was bone marrow (28%), a higher frequency than that for CD5- DLBCL (P <.0001) but lower than that for cyclin D1+ MCL (P =.0015). Histopathologically, CD5+ DLBCL showed centroblastic morphology except for 3 patients with immunoblastic disease, and interfollicular growth pattern (7%) and intravascular or intrasinusoidal infiltration (19%) were observed. Immunophenotypically, CD5+ DLBCL was characterized by a CD5+CD10-CD19+CD20+CD21-CD23- cyclin D1- phenotype and a predominance of surface IgMkappa. Of particular interest is that CD5+ DLBCL was characterized by a survival curve significantly inferior to that for patients with CD5- DLBCL (P =.0026). These findings suggest that CD5+ DLBCL may constitute a unique subgroup of DLBCL.  相似文献   
73.
A rabbit antiserum obtained by immunization with spleen cells of nu/nu mice, known to be deficient in thymus and T cells but not in T cell precursor, possesses two different specificities. In addition to activity against bone marrow-derived lymphocytes (B cells), as revealed by inhibition of antibody forming cells and myeloma cells, the antiserum (Ra-nu/nu) has strong activity against cytotoxic T cells but not against helper T cells. Differences in sensitivity to antiserum treatment between anatomically and functionally distinct B cells point to surface antigenic differences among subclasses of B cells.  相似文献   
74.
In adoptive T-cell transfer as an intervention for malignant diseases, retroviral transfer of T-cell receptor (TCR) genes derived from CD8(+) cytotoxic T-lymphocyte (CTL) clones provides an opportunity to generate a large number of T cells with the same antigen specificity. We cloned the TCR-alphabeta genes from a human leukocyte antigen (HLA)-A(*)2402-restricted CTL clone specific for MAGE-A4(143-151). The TCR-alphabeta genes were transduced to 99.2% of non-TCR expressing SupT1, a human T-cell line, and to 12.7-32.6% of polyclonally activated CD8(+) T cells by retroviral transduction. As expected, TCR-alphabeta gene-modified CD8(+) T cells showed cytotoxic activity and interferon-gamma production in response to peptide-loaded T2-A(*)2402 and tumor cell lines expressing both MAGE-A4 and HLA-A(*)2402. A total of 24 clones were established from TCR-alphabeta gene-transduced peripheral blood mononuclear cells and all clones were functional on a transduced TCR-dependent manner. Four clones were kept in culture over 6 months for analyses in detail. The transduced TCR-alphabeta genes were stably maintained phenotypically, functionally and genetically. Our results indicate that TCR-transduced alphabeta T cells by retroviral transduction represent an efficient and promising strategy for adoptive T-cell transfer for long term.  相似文献   
75.
Short-term culture of peripheral blood mononuclear cells (PBMC) derived from patients with human T cell lymphotropic virus type I-associated myelopathy (HAM)/tropical spastic paraparesis resulted in dominance by DR+ activated CD8+ T cells. Variations in the T cell receptor (TCR) V alpha and V beta chains in these cells were analyzed, and in all 10 patients examined, 2-3 V gene families were dominant in both TCR V alpha and V beta. In five patients we examined, cultured lymphocytes contained cytotoxic lymphocytes for p40tax (patients HAM2, 3, 7, and 8) or env protein (patient HAM4) of human T lymphotropic virus type I. In patients HAM2 and HAM8, cultured lymphocytes contained a large proportion of V beta 8+ CD8+ and/or V beta 12+ CD8+ cells. The sequence of V beta 8+ and V beta 12+ cDNA revealed that they were oligoclonal with identical or similar sequences in each patient. Elimination experiments with monoclonal antibodies for TCR V beta 8 and V beta 12 showed that they were CD8+ cytotoxic T lymphocytes (CTL) for p40tax. In addition, flow cytometry and sequencing analysis of uncultured PBMC revealed that in HAM2, V beta 8+ CTL and their precursors account for 7% and V beta 12+ CTL and their precursors account for 18% of total CD8+ cells. This indicates the presence of two markedly expanded clones in vivo. No common dominant TCR V alpha or V beta were observed among 10 HAM patients analyzed.  相似文献   
76.
We describe a 55-year-old Japanese woman with therapy-related myelodysplastic syndrome (t-MDS) with 2 independent clones, t(1;2)(p36;p21) and t(11;12)(pl5;ql3). She was diagnosed with acute myeloid leukemia (AML) with cytological features of the bone marrow and peripheral blood. Cytogenetic evaluation revealed a 46,XX karyotype. She received chemotherapy and achieved complete remission (CR). Despite maintenance chemotherapy, she suffered a relapse. Chromosomal analysis showed t(1;2)(p36;p21) in 2 of 20 metaphases. At second CR, this clone transiently disappeared. Nine months later, t(1;2) (p36;p21) was detected again in 3 of 20 metaphases while the patient remained in CR. Six months later, bone marrow examination disclosed trilineage dysplasia without an excess of blasts, suggesting MDS. t(1;2)(p36;p21) was observed in 16 of 20 metaphases. The clinical course and serial cytogenetic findings were diagnostic of t-MDS. The duration of t-MDS was 6 years. During this period, persistent t(1;2)(p36;p21) and transient t(11;12)(p15;q13) were found. When t-MDS evolved toAML, cytogenetic evaluation revealed 46,XX,t(1;2)(p36;p21),del(7)(q22),add(19)(p13).  相似文献   
77.
Reticulated platelets (RP) and large platelets (LP) were measured by an automated hematology analyzer (modified R-2000) in 287 healthy volunteers and 131 patients with thrombocytopenia or thrombocytosis. RP was significantly higher in patients with idiopathic thrombocytopenic purpura (ITP), especially in active phase, while RP was markedly lower in patients with essential thrombocytosis (ET) or chronic myelocytic leukemia (CML). LP was significantly higher in patients with ITP, especially in active phase, while LP was markedly lower in patients with aplastic anemia (AA), ET, or CML. In ITP, RP and LP were significantly higher in patients positive for anti-glycoprotein (Gp) IIb/IIIa antibody. RP and LP were poorly correlated with platelet-associated IgG (PAIgG). RP and LP were poorly correlated with plasma thrombopoietin levels, and negatively correlated with platelet count. These results show that RP reflects the pathology of thrombocytopenic disorders, and that measurement of RP is useful for the differential diagnosis and analysis of platelet kinetics.  相似文献   
78.
Thrombomodulin (TM) has been under development as a medicine for disseminated intravascular coagulation (DIC), and is expected to exhibit strong anticoagulant activity by inhibiting thrombin generation via the acceleration of protein C activation. In the present study, we examined the pharmacological action of TM in plasma obtained from DIC patients. TM was found to inhibit thrombin generation and accelerate activated protein C (APC) production at 0.3-30 TM units/ml in plasma obtained from DIC patients irrespective of their underlying disorders. In addition, there was a positive correlation between the inhibition of thrombin generation and the amount of APC produced. Thrombin generation was inhibited by over 50% when the plasma level of APC was increased by more than 0.2 microg/ml. These results indicate that TM inhibits thrombin generation in plasma obtained from DIC patients by accelerating APC production. Moreover, the results imply that the thrombin generation test may be a good method to speculate the efficacy of TM on every patient before the administration of TM.  相似文献   
79.
We examined the actions of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) on human monocytes, using a serum-free culture system. GM-CSF and IL-3 did not promote the differentiation of monocytes into macrophages but rather into cells with a phenotype compatible with that of immature dendritic cells (DCs). The addition of fetal bovine serum to serum-free cultures with GM-CSF or IL-3 restored the differentiation of monocytes into macrophages. Cells generated with GM-CSF or IL-3 elicited phagocytic activity. Cells generated in the presence of GM-CSF or IL-3, followed by the addition of tumor necrosis factor-alpha, displayed a phenotype of mature DCs, and primed and stimulated immunogenic peptide-specific T lymphocytes. Surprisingly, GM-CSF and IL-3 inhibited macrophage colony-stimulating factor (M-CSF)-dependent differentiation of monocytes into macrophages and induced differentiation into immature DCs. We asked if the inhibition of M-CSF-dependent differentiation into macrophages by GM-CSF or IL-3 was associated with the expression of M-CSF receptors (M-CSFR). GM-CSF or IL-3 down-regulated the expression of M-CSFR. These data demonstrate that GM-CSF and IL-3 primarily support the differentiation of monocytes into DCs and inhibit M-CSF-dependent differentiation into macrophages by suppressing the expression of M-CSFR, thereby promoting differentiation into DCs.  相似文献   
80.
We report a 31-year-old female with t(8;21)(q22;q22) acute myeloid leukemia (AML), M2 in the FAB classification. Complete remission was achieved with daunorubicin and cytarabine induction therapy followed by three courses of high-dose cytarabine consolidation. Only 3 months later, the patient relapsed with granulocytic sarcomas (GSs) in her rhinopharynx, external acoustic meatus, and bone marrow. She received focal radiation for the GSs and successfully underwent reinduction chemotherapy. Subsequently, she received a matched related donor peripheral blood stem cell transplantation followed by high-dose chemotherapy and is now in a second remission. We summarized 79 reported cases of t(8;21) AML with GS and reviewed the literature to identify differences in the characteristics of t(8;21) AML with GS between adults and children. To our knowledge, this is the first report of pharyngeal GS in t(8;21) AML, and focal irradiation plus more intensive postinduction therapy during first remission, such as allogeneic-SCT, may be effective in adult t(8;21) AML patients with GS.  相似文献   
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