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排序方式: 共有892条查询结果,搜索用时 15 毫秒
91.
Jarolim P; Rubin HL; Brabec V; Chrobak L; Zolotarev AS; Alper SL; Brugnara C; Wichterle H; Palek J 《Blood》1995,85(3):634-640
To elucidate the molecular basis of band 3 deficiency in a recently defined subset of patients with autosomal dominant hereditary spherocytosis (HS), we screened band 3 cDNA for single-strand conformation polymorphism (SSCP). In 5 of 17 (29%) unrelated HS subjects with band 3 deficiency, we detected substitutions R760W, R760Q, R808C, and R870W that were all coinherited with the HS phenotype. The involved arginines are highly conserved throughout evolution. To examine whether or not the product of the mutant allele is inserted into the membrane, we studied one HS subject who was doubly heterozygous for the R760Q mutation and the K56E (band 3sMEMPHIS) polymorphism that results in altered electrophoretic mobility of the band 3 Memphis proteolytic fragments. We detected only the band 3MEMPHIS in the erythrocyte membrane indicating that the protein product of the mutant, R760Q, band 3 allele is absent from the red blood cell membrane. These findings suggest that the R760Q substitution, and probably the other arginine subsitutions, produce band 3 deficiency either by precluding incorporation of the mutant protein into the red blood cell membrane or by leading to loss of mutant protein from differentiating erythroid precursors. 相似文献
92.
93.
Activation of human platelets by immune complexes prepared with cationized human IgG 总被引:1,自引:0,他引:1
Schattner M; Lazzari M; Trevani AS; Malchiodi E; Kempfer AC; Isturiz MA; Geffner JR 《Blood》1993,82(10):3045-3051
The present study shows that the ability of soluble immune complexes (IC), prepared with human IgG and rabbit IgG antibodies against human IgG, to trigger platelet activation was markedly higher for IC prepared with cationized human IgG (catIC) compared with those prepared with untreated human IgG (cIC). CatIC induced platelet aggregation and adenosine triphosphate release in washed platelets (WP), gel-filtered platelets (GFP), or platelet-rich plasma (PRP) at physiologic concentrations of platelets (3 x 10(8)/mL) and at low concentrations of catIC (1 to 30 micrograms/mL). On the contrary, under similar experimental conditions, cIC did not induce aggregation in PRP, WP, or GFP. Low aggregation responses were only observed using high concentrations of both WP (9 x 10(8)/mL) and cIC (500 micrograms/mL). Interestingly, catIC were also able to induce platelet activation under nonaggregating conditions, as evidenced by P-selectin expression. Cationized human IgG alone did not induce platelet aggregation in PRP but triggered either WP or GFP aggregation. However, the concentration needed to induce these responses, was about eightfold higher than those required for catIC. The responses induced either by catIC or cationized human IgG were completely inhibited by treatment with heparin, dextran sulphate, EDTA, prostaglandin E1, or IV3, a monoclonal antibody against the receptor II for the Fc portion of IgG (Fc gamma RII). The data presented in this study suggest that IgG charge constitutes a critical property that conditions the ability of IC to trigger platelet activation. 相似文献
94.
Gamma (immune) interferon production by leukocytes from a patient with a TG cell proliferative disease 总被引:7,自引:0,他引:7
We report a patient with a disease characterized by proliferation of T cells with Fc receptors for IgG (TG). However, unlike lymphoid cells from normal individuals or from patients with other lymphoid malignancies, the patient's lymphocytes spontaneously produced gamma interferon (IFN-gamma) in vitro. The peripheral lymphocytes consisted of 95% TG cells, which exhibited the morphological characteristics of T- cell chronic lymphocytic leukemia (CLL) and were normal on cytochemical and chromosome analysis. The majority of TG cells were OKT3+, OKT8+, and OKT4-, 3A1-. These cells failed to express suppressor cell activity and displayed depressed levels of natural killer activity, but mediated antibody-dependent cell-mediated cytotoxicity. The spontaneous production of IFN-gamma by human peripheral lymphoid cells as demonstrated in this study may serve as a probe for studying the relationship between IFN-gamma and the proliferation of human T-cell subsets. 相似文献
95.
Autologous and allogeneic bone marrow transplantation for poor prognosis patients with B-cell chronic lymphocytic leukemia 总被引:2,自引:4,他引:2
Rabinowe SN; Soiffer RJ; Gribben JG; Daley H; Freedman AS; Daley J; Pesek K; Neuberg D; Pinkus G; Leavitt PR 《Blood》1993,82(4):1366-1376
Twenty patients with poor prognosis B-cell chronic lymphocytic leukemia (B-CLL) underwent uniform high-dose chemoradiotherapy followed by rescue with multiple monoclonal antibody-purged autologous bone marrow (BM) (12 patients) or T-cell-depleted allogeneic BM from HLA-identical siblings (8 patients) in a pilot study to assess the feasibility of BM transplantation (BMT) in this disease. All had poor prognosis disease by either staging, BM pattern, tumor doubling time criteria, or cytogenetics. All patients achieved remission criteria (defined as < or = 2 adenopathy, absence of splenomegaly, < or = 20% of the intertrabecular space involved on BM biopsy) before BMT. Despite the use of fludarabine, a median of three treatment regimens were required to achieve BMT eligibility. After BMT, all patients achieved complete hematologic engraftment. Toxicities were not significantly different between autologous versus allogeneic BMT. Two toxic deaths were observed. Of 19 evaluable patients, 17 clinical complete clinical remissions (89%) were observed, with 2 patients (1 allogeneic and 1 autologous) exhibiting persistent BM disease. Complete clinical remissions were documented at the phenotypic and molecular level for the majority of patients in whom dual fluorescence for CD5 and CD20 (15 of 15; 100%) and Ig gene rearrangements (11 of 14; 79%) were performed. Although long-term follow-up is needed to assess any potential impact on the disease-free and overall survival of these patients, this study shows the feasibility of using high-dose chemoradiotherapy and BMT in patients with poor prognosis B-CLL. 相似文献
96.
Stimulation of tyrosine phosphorylation after ligation of beta7 and beta1 integrins on human B cells 总被引:2,自引:0,他引:2
Manie SN; Astier A; Wang D; Phifer JS; Chen J; Lazarovits AI; Morimoto C; Freedman AS 《Blood》1996,87(5):1855-1861
B lymphocytes express several members of the integrin family of adhesion molecules that mediate cell-cell and cell-extracellular matrix interactions. In addition to beta1 integrins, predominantly alpha4 beta1, mature B cells also express alpha4 beta7, which is a receptor for vascular cell adhesion molecule-1 and fibronectin, and is also involved in the homing of B cells to mucosal sites through binding to a third ligand, mucosal address in cell adhesion molecule-1. Here we describe that crosslinking of alpha4 beta7 integrins on B cell lines and normal tonsillar B cells, induces tyrosine phosphorylation of multiple substrates of 105-130 kD, indicating that beta7 integrin plays a role as signaling molecule in B cells. This pattern of phosphorylated proteins was very similar to that induced following ligation of alpha4 beta1. Interestingly, ligation of alpha5 beta1 or alpha6 beta1 also stimulated the 105-125 kD group of phosphorylated proteins, whereas ligation of beta2 integrins did not. The focal adhesion tyrosine kinase p125FAK was identified as one of these substrates. Beta1 or beta7 mediated tyrosine phosphorylations were markedly decreased when the microfilament assembly was inhibited by cytochalasin B. These results suggest that intracellular signals initiated by different integrins in B cells may converge, to similar cytoskeleton-dependent tyrosine phosphorylated proteins. 相似文献
97.
Freedman AS; Boyd AW; Bieber FR; Daley J; Rosen K; Horowitz JC; Levy DN; Nadler LM 《Blood》1987,70(2):418-427
In an attempt to compare B cell chronic lymphocytic leukemia (B-CLL) with its normal cellular counterpart, the cell surface phenotype of 100 cases of B-CLL was determined by using a panel of monoclonal antibodies (MoAbs) directed against B cell-restricted and -associated antigens. The majority of B-CLL cells expressed Ia, B4 (CD19), B1 (CD20), B2 (CD21), surface immunoglobulin (sIg), and T1 (CD5) but lacked C3b (CD35) receptors. In contrast, the overwhelming majority of small unstimulated B cells expressed Ia, B4, B1, B2, sIg, and C3b receptors but lacked detectable T1. Small numbers of weakly sIg+ cells could be identified in peripheral blood and tonsil that coexpressed the B1 and T1 antigens. Approximately 16% of fetal splenocytes coexpressed B1, T1, weak sIg, B2, and Ia but lacked C3b receptors and therefore closely resembled most B-CLL cells. With the phenotypic differences between the majority of small unstimulated B cells and B-CLL cells, we examined normal in vitro activated B cells and B-CLL cells for the expression of B cell-restricted and -associated activation antigens. Of 20 cases examined, virtually all expressed B5, and approximately 50% of the cases expressed interleukin-2 receptors (IL-2R) and Blast-1. Normal B cells were activated with either anti-Ig or 12-0-tetradecanoylphorbol- beta-acetate (TPA) and then were examined for coexpression of B1, T1, and the B cell activation antigens B5 and IL-2R. Only cells activated with TPA coexpressed B1 and T1 as well as B5 and IL-2R. B cells activated with either anti-Ig or TPA proliferated in the presence of IL- 2, whereas B-CLL cells did not, although they all expressed the identical 60-kilodalton proteins by immunoprecipitation. These studies are consistent with the notion that B-CLL resembles several minor subpopulations of normal B cells including a population of B cells that are activated in vitro directly through the protein kinase C pathway. 相似文献
98.
Bone marrow transplantation for patients with Philadelphia chromosome- positive acute lymphoblastic leukemia 总被引:1,自引:2,他引:1
Forman SJ; O'Donnell MR; Nademanee AP; Snyder DS; Bierman PJ; Schmidt GM; Fahey JL; Stein AS; Parker PM; Blume KG 《Blood》1987,70(2):587-588
We report the treatment outcome of allogeneic bone marrow transplantation in ten patients with Philadelphia chromosome-positive acute lymphoblastic leukemia. Six patients are alive and well for 6 to 30 months (median 19 months) after transplantation. Four patients died with transplant related complications. In view of the poor prognosis associated with this disease, marrow ablation followed by allogeneic or syngeneic marrow grafting may be the preferred treatment modality if a suitable marrow donor is available. 相似文献
99.
Immunologic heterogeneity of diffuse large cell lymphoma 总被引:2,自引:0,他引:2
Freedman AS; Boyd AW; Anderson KC; Fisher DC; Pinkus GS; Schlossman SF; Nadler LM 《Blood》1985,65(3):630-637
The cellular lineage of 57 diffuse large-cell lymphomas (DLCLs) was determined using a panel of monoclonal antibodies directed against lineage-restricted and -associated T, B, and monocyte antigens. The majority (82%) were of B cell lineage as determined by the expression of sig and/or B1, with the remaining 16% being of T cell lineage and 2%, of monocyte-myeloid lineage. By the expression of other B cell- restricted and -associated antigens, two major and two minor subgroups could be identified. These subgroups expressed the following phenotypes: (1) B1+B4+sIG+B2- (51%); (2) B1+B4+sIg+B2+ (29%); (3) B1+B4+sIg-B2+ (10%); and (4) B1+B4-sIg+B2- (10)%. The morphology of transformed lymphocytes, the weak to absent expression of the early B cell antigens B2 and sIgD, and the absence of the late B cell differentiation antigens PCA-1 and PC-1 suggested that these tumors were the neoplastic counterparts of normal B cells at the mid-stages of differentiation. Further support for the notion that B-DLCLs correspond to transformed B lymphocytes was concluded from the observation that B cells could be identified in normal spleen that expressed the cell surface phenotype and morphological appearance of the majority of B- DLCLs. 相似文献
100.
Snyder DS; Negrin RS; O'Donnell MR; Chao NJ; Amylon MD; Long GD; Nademanee AP; Stein AS; Parker PM; Smith EP 《Blood》1994,84(5):1672-1679
Ninety-four consecutive patients with chronic myelogenous leukemia in first clinical chronic phase, median age of 34.0 years (range, 6.8 to 52.4 years), with a histocompatible sibling donor, were treated with fractionated total body irradiation (1,320 cGy) and high-dose etoposide (60 mg/kg) followed by allogeneic bone marrow transplantation (BMT). The median time from diagnosis to BMT was 7.0 months (range, 2.3 to 72.0 months). Sixty patients were treated before BMT with hydroxyurea alone, four patients with busulfan alone, one patient with interferon alone, and the other 29 patients were treated with various combinations of these drugs. Cumulative probabilities of overall survival, event- free survival, and relapse at 5 years were 73%, 64%, and 14%, respectively. The median follow-up time for surviving patients was 38 months, ranging from 12 to 88 months. By stepwise Cox regression analysis, significant prognostic variables were age at transplant, acute graft-versus-host disease > or = grade II, cytomegalovirus- associated interstitial pneumonitis, and years from diagnosis to BMT. 相似文献