bluuebunny/crossref_metadata_2025_split huggingface dataset:
Complexity within the plasma cell compartment of mice deficient in both E- and P-selectin: implications for plasma cell differentiation
Authors: Underhill Gregory H. , Kolli K. Pallav , Kansas Geoffrey S. 
Published: July 2003

AbstractAntibody-secreting plasma cells represent the critical end-stage effector cells of the humoral immune response. Here, we show that several distinct plasma cell subsets are concurrently present in the lymph nodes, spleen, and bone marrow of mice deficient in both E- and P-selectin. One of these subsets was a B220-negative immunoglobulin g (IgG) plasma cell population expressing low to negative surface levels of syndecan-1. Examination of the chemotactic responsiveness of IgG plasma cell subsets revealed that migration toward stromal cell-derived factor 1/CXC ligand 12 (SDF-1/CXCL12) was primarily limited to the B220-lo subset regardless of tissue source. Although B220-negative plasma cells did not migrate efficiently in response to CXCL12 or to other chemokines for which receptor mRNA was expressed, these cells expressed substantial surface CXC chemokine receptor-4 (CXCR4), and CXCL12 stimulation rapidly induced extracellular signal regulated kinase 1 (ERK1)/ERK2 phosphorylation, demonstrating that CXCR4 retained signaling capacity. Therefore, B220-negative plasma cells exhibit a selective uncoupling of chemokine receptor expression and signaling from migration. Taken together, our findings document the presence of significant heterogeneity within the plasma cell compartment, which suggests a complex step-wise scheme of plasma cell differentiation in which the degree of differentiation and tissue location can influence the chemotactic responsiveness of IgG plasma cells. (Blood. 2003;102:4076-4083)
The kringle stabilizes urokinase binding to the urokinase receptor
Authors: Bdeir Khalil , Kuo Alice , Sachais Bruce S. , Rux Ann H. , Bdeir Yasmina , Mazar Andrew , Higazi Abd Al-Roof , Cines Douglas B. 
Published: July 2003

AbstractThe structural basis of the interaction between single-chain urokinase-type plasminogen activator (scuPA) and its receptor (uPAR) is incompletely defined. Several observations indicated the kringle facilitates the binding of uPA to uPAR. A scuPA variant lacking the kringle (ΔK-scuPA) bound to soluble uPAR (suPAR) with the similar “on-rate” but with a faster “off-rate” than wild-type (WT)-scuPA. Binding of ΔK-scuPA, but not WT-scuPA, to suPAR was comparably inhibited by its growth factor domain (GFD) and amino-terminal fragment (ATF). ATF and WT-scuPA, but not GFD, scuPA lacking the GFD (ΔGFD-scuPA), or ΔK-scuPA reconstituted the isolated domains of uPAR. ATF completely inhibited the enzymatic activity of WT-scuPA-suPAR unlike comparable concentrations of GFD. Variants containing mutations that alter the charge, length, or flexibility of linker sequence (residues 43-49) between the GFD and the kringle displayed a lower affinity for uPAR, were unable to reconstitute uPAR domains, and their binding to uPAR was inhibited by GFD in the same manner as ΔK-scuPA. A scuPA variant in which the charged amino acids in the heparin binding site (HBS) in the kringle domain were mutated to alanines behaved like ΔK-scuPA, indicating that that the structure of the kringle as well as its interaction with the GFD govern receptor binding. These data demonstrate an important role for the kringle in stabilizing the binding of scuPA to uPAR. (Blood. 2003;102:3600-3608)
Flexible migration program regulates γδ T-cell involvement in humoral immunity
Authors: Brandes Marlène , Willimann Katharina , Lang Alois B. , Nam Ki-Hoan , Jin Chenggang , Brenner Michael B. , Morita Craig T. , Moser Bernhard 
Published: July 2003

Abstractγδ T cells are inadequately defined both in terms of their migration potential and contribution to antimicrobial immunity. Here, we have examined the migration profile of human blood γδ T cells and related cell lines and correlated these findings with their distribution in secondary lymphoid tissues and their function in B-cell cocultures. We find that resting γδ T cells are characterized by an inflammatory migration program similar to cells of the innate immune system. However, T-cell receptor (TCR) triggering resulted in the rapid but transient induction of a lymph node (LN)-homing program, as evidenced by functional CCR7 expression and concomitant reduction in expression and function of CCR5 and, to a lesser degree, CCR2. Moreover, the LN-homing program was reflected by the presence of γδ T cells in gastrointestinal lymphoid tissues, notably in clusters within germinal centers of B-cell follicles. In line with these findings, VγVδ-TCR triggering resulted in prominent expression of essential B-cell costimulatory molecules, including CD40L, OX40, CD70, and ICOS. Furthermore, γδ T cells were shown to provide potent B-cell help during in vitro antibody production. Collectively, our findings agree with a role for γδ T cells in humoral immunity during the early phase of antimicrobial responses. (Blood. 2003; 102:3693-3701)
Rapid induction of complete donor chimerism by the use of a reduced-intensity conditioning regimen composed of fludarabine and melphalan in allogeneic stem cell transplantation for metastatic solid tumors
Authors: Ueno Naoto T. , Cheng Yee Chung , Rondón Gabriela , Tannir Nizar M. , Gajewski James L. , Couriel Daniel R. , Hosing Chitra , de Lima Marcos J. , Anderlini Paolo , Khouri Issa F. , Booser Daniel J. , Hortobagyi Gabriel N. , Pagliaro Lance C. , Jonasch Eric , Giralt Sergio A. , Champlin Richard E. 
Published: July 2003

AbstractWe evaluated the feasibility and efficacy of a reduced-intensity conditioning (RIC) regimen of fludarabine and melphalan to achieve rapid complete donor chimerism after allogeneic stem cell transplantation (SCT) in patients with metastatic solid tumors. Between January 1999 and January 2003, 8 patients with metastatic breast cancer (BC) and 15 with metastatic renal cell carcinoma (RCC) underwent allogeneic SCT after an RIC regimen of 5 days of fludarabine and 2 days of melphalan. Filgrastim-mobilized stem cells from HLA-identical related or unrelated donors were infused. Prophylaxis for graft-versus-host disease (GVHD) consisted of tacrolimus and methotrexate. All 22 evaluable patients had 100% donor chimerism at day 30 and at all measurement times thereafter. One patient died 19 days after SCT. Nine patients (39%) had grades II to IV acute GVHD and 10 patients (43%) had chronic GVHD. Five patients (22%) died of nonrelapse treatment-related complications. Treatment-related disease response was seen in 10 patients (45%), with 3 complete responses, 2 partial responses, and 5 minor responses. Fludarabine-melphalan is a feasible and effective RIC regimen for allogeneic SCT in metastatic BC and RCC. It induces rapid complete donor chimerism without the need for donor lymphocyte infusion. Tumor regression associated with GVHD is consistent with graft-versus-tumor effect. (Blood. 2003;102:3829-3836)
Recombinant humanized anti-IL-2 receptor antibody (daclizumab) produces responses in patients with moderate aplastic anemia
Authors: Maciejewski Jaroslaw P. , Sloand Elaine M. , Nunez Olga , Boss Carol , Young Neal S. 
Published: July 2003

AbstractIn contrast to severe aplastic anemia (sAA), the appropriate management of patients with moderate pancytopenia is unclear. In this study, we examined the efficacy of a humanized monoclonal antibody recognizing interleukin-2 receptor (daclizumab), which has proven to be a successful immunosuppressive agent in solid organ and bone marrow transplantation. We treated 17 patients with moderate aplastic anemia (mAA) with 1 mg/kg every 2 weeks for 3 months. mAA was defined as depression of 2 of the 3 blood counts: absolute neutrophil count 1200/mm3 or less, platelet count 70 000/mm3 or less, hemoglobin level 8.5 g/dL or lower, and absolute reticulocyte count 60 000/mm3 or less. The primary end point of our protocol was a hematologic response in at least one affected peripheral blood value. Daclizumab had little toxicity. Six of the 16 (38%) evaluable patients responded to treatment. Two patients with previously chronic disease showed complete return of normal counts, which were sustained for more than 2 years following treatment. Four patients had single-lineage responses. Two previously transfusion-dependent patients became transfusion independent; one patient with many neutropenia-related infections had a normal neutrophil count following treatment. Daclizumab appears safe; its efficacy in this pilot protocol suggests that expanded study of this monoclonal antibody in immune-mediated bone marrow failure syndrome is warranted. (Blood. 2003; 102:3584-3586)
Transferrin receptor 1 is differentially required in lymphocyte development
Authors: Ned Renée M. , Swat Wojciech , Andrews Nancy C. 
Published: July 2003

AbstractTransferrin receptor (TfR) facilitates cellular iron uptake by mediating endocytosis of its ligand, iron-loaded transferrin. Although TfR is widely believed to be important for iron acquisition by all mammalian cells, direct experimental evidence is lacking. We have previously shown that mouse embryos homozygous for a disrupted transferrin receptor allele (TfR-/-) die of anemia before embryonic day 12.5, although most other embryonic tissues appear to be developing normally. Here, we have investigated the importance of TfR postnatally, by using TfR-/- embryonic stem cells to produce chimeric animals. We find that TfR-/- embryonic stem cells give rise to most tissues and organs, but do not contribute to hematopoietic tissues on a wild-type C57BL/6J background, indicating that both adult erythropoiesis and lymphopoiesis require TfR. On an immunodeficient RAG2-/- background, TfR-/- B-cell development proceeds at least to the IgM+ stage, although significantly fewer IgM+ cells are present in peripheral lymphoid organs. Conversely, T cells lacking TfR are arrested very early in their development, at the CD4-8-3- stage. These results indicate that TfR is necessary for the normal maturation of thymocytes, but that B-cell development is less severely affected by the absence of TfR. (Blood. 2003;102:3711-3718)
Immunosuppressive effect of mesenchymal stem cells favors tumor growth in allogeneic animals
Authors: Djouad Farida , Plence Pascale , Bony Claire , Tropel Philippe , Apparailly Florence , Sany Jacques , Noël Danièle , Jorgensen Christian 
Published: July 2003

AbstractMesenchymal stem cells (MSCs) are largely studied for their potential clinical use. Recently, they have gained further interest after demonstration of an immunosuppressive role. In this study, we investigated whether in vivo injection of MSCs could display side effects related to systemic immunosuppression favoring tumor growth. We first showed in vitro that the murine C3H10T1/2 (C3) MSC line and primary MSCs exhibit immunosuppressive properties in mixed lymphocyte reaction. We demonstrated that this effect is mediated by soluble factors, secreted only on “activation” of MSCs in the presence of splenocytes. Moreover, the immunosuppression is mediated by CD8+ regulatory cells responsible for the inhibition of allogeneic lymphocyte proliferation. We then demonstrated that the C3 MSCs expressing the human bone morphogenetic protein 2 (hBMP-2) differentiation factor were not rejected when implanted in various allogeneic immunocompetent mice and were still able to differentiate into bone. Importantly, using a murine melanoma tumor model, we showed that the subcutaneous injection of B16 melanoma cells led to tumor growth in allogeneic recipients only when MSCs were coinjected. Although the potential side effects of immunosuppression induced by MSCs have to be considered in further clinical studies, the usefulness of MSCs for various therapeutic applications still remains of great interest. (Blood. 2003;102:3837-3844)
Coinheritance of Factor V (FV) Leiden enhances thrombin formation and is associated with a mild bleeding phenotype in patients homozygous for the FVII 9726+5G&gt;A (FVII Lazio) mutation
Authors: Castoldi Elisabetta , Govers-Riemslag José W. P. , Pinotti Mirko , Bindini Debora , Tans Guido , Berrettini Mauro , Mazzucconi Maria Gabriella , Bernardi Francesco , Rosing Jan 
Published: July 2003

AbstractWe investigated the role of thrombophilic mutations as possible modifiers of the clinical phenotype in severe factor VII (FVII) deficiency. Among 7 patients homozygous for a cross-reacting material-negative (CRM-) FVII defect (9726+5G&gt;A, FVII Lazio), the only asymptomatic individual carried FV Leiden. Differential modulation of FVII levels by intragenic polymorphisms was excluded by a FVII to factor X (FX) gene haplotype analysis. The coagulation efficiency in the FV Leiden carrier and a noncarrier was evaluated by measuring FXa, FVa, and thrombin generation after extrinsic activation of plasma in the absence and presence of activated protein C (APC). In both patients coagulation factor activation was much slower and resulted in significantly lower amounts of FXa and thrombin than in a normal control. However, more FXa and thrombin were formed in the plasma of the patient carrying FV Leiden than in the noncarrier, especially in the presence of APC. These results were confirmed in FV-FVII doubly deficient plasma reconstituted with purified normal FV or FV Leiden. The difference in thrombin generation between plasmas reconstituted with normal FV or FV Leiden gradually decreased at increasing FVII concentration. We conclude that coinheritance of FV Leiden increases thrombin formation and can improve the clinical phenotype in patients with severe FVII deficiency. (Blood. 2003;102:4014-4020)
A rare complex DNA rearrangement in the murine Steel gene results in exon duplication and a lethal phenotype
Authors: Chandra Saurabh , Kapur Reuben , Chuzhanova Nadia , Summey Victoria , Prentice David , Barker Jane , Cooper David N. , Williams David A. 
Published: July 2003

AbstractKit ligand (Kitl), encoded by the Steel (Sl) locus, plays an essential role in hematopoiesis, gametogenesis, and melanogenesis during both embryonic and adult life. We have characterized a new spontaneous mutant of the Sl locus in mice designated KitlSl-20J that arose in the breeding colony at Jackson Laboratories. Heterozygous KitlSl-20J mice display a white belly spot and intercrossing results in an embryonic lethal phenotype in the homozygous state. Analysis of homozygous embryos demonstrated a significant reduction in fetal liver cellularity, colony forming unit-erythroid (CFU-E) progenitors, and a total absence of germ cells. Although expressed in vivo, recombinant mutant protein demonstrated loss of bioactivity that was correlated with lack of receptor binding. Analysis of the Sl gene transcripts in heterozygous KitlSl-20J mice revealed an in-frame tandem duplication of exon 3. A long-range polymerase chain reaction (PCR) strategy using overlapping primers in exon 3 amplified an approximately 7-kilobase (kb) product from DNA isolated from heterozygous KitlSl-20J mice but not from wild-type DNA that contained sequences from both introns 2 and 3 and an inverted intron 2 sequence, suggesting a complex rearrangement as the mechanism of the mutation. “Complexity analysis” of the sequence of the amplified product strongly suggests that local DNA motifs may have contributed to the generation of this spontaneous KitlSl-20J allele, likely mediated by a 2-step process. The KitlSl-20J mutation is a unique KitlSl allele and represents an unusual mechanism of mutation. (Blood. 2003;102:3548-3555)
Factor VIII ectopically expressed in platelets: efficacy in hemophilia A treatment
Authors: Yarovoi Helen V. , Kufrin Dubravka , Eslin Don E. , Thornton Michael A. , Haberichter Sandra L. , Shi Qizhen , Zhu Hua , Camire Rodney , Fakharzadeh Steve S. , Kowalska M. Anna , Wilcox David A. , Sachais Bruce S. , Montgomery Robert R. , Poncz Mortimer 
Published: July 2003

Abstract
Activated platelets release their granule content in a concentrated fashion at sites of injury. We examined whether ectopically expressed factor VIII in developing megakaryocytes would be stored in α-granules and whether its release from circulating platelets would effectively ameliorate bleeding in a factor VIIInull mice model. Using the proximal glycoprotein 1bα promoter to drive expression of a human factor VIII cDNA construct, transgenic lines were established. One line had detectable human factor VIII that colocalizes with von Willebrand factor in platelets. These animals had platelet factor VIII levels equivalent to 3% to 9% plasma levels, although there was no concurrent plasma human factor VIII detectable. When crossed onto a factor VIIInull background, whole blood clotting time was partially corrected, equivalent to a 3% correction level. In a cuticular bleeding time study, these animals also had only a partial correction, but in an FeCl3 carotid artery, thrombosis assay correction was equivalent to a 50% to 100% level. These studies show that factor VIII can be expressed and stored in platelet α-granules. Our studies also suggest that platelet-released factor VIII is at least as potent as an equivalent plasma level and perhaps even more potent in an arterial thrombosis model. (Blood. 2003;102:4006-4013)
Calcium-and integrin-binding protein regulates focal adhesion kinase activity during platelet spreading on immobilized fibrinogen
Authors: Naik Meghna U. , Naik Ulhas P. 
Published: July 2003

AbstractPlatelet spreading on the subendothelium in response to vascular injury is fundamental to the regulation of physiologic hemostasis. Previously, we have shown that, when bound to glycoprotein IIb (GPIIb), calcium- and integrin-binding protein (CIB) regulates platelet spreading on immobilized fibrinogen (Fg). In this study, we investigated the signaling events that occur downstream of CIB in the absence of signaling that occurs as a result of granular secretion. Using Chinese hamster ovary (CHO) cells as a model, we demonstrate that CIB induces cell migration. Immunofluorescence analysis of CIB localization indicates that endogenous CIB accumulates in areas of focal adhesions, and its overexpression up-regulates the formation of focal adhesion complexes compared with control cells. Immunoprecipitation analysis indicates that CIB associates with focal adhesion kinase (FAK), a key regulator in focal complex formation, and up-regulates its activity. Overexpression of dominant-negative FAK, FRNK, along with CIB in CHO cells completely inhibits CIB-induced cell migration. Further, confirmation of these data in the platelet system indicates that CIB and FAK associate throughout all stages of platelet spreading but only on Fg binding to GPIIb/IIIa. Taken together, our results suggest that CIB regulates platelet spreading through the regulation of FAK activation. (Blood. 2003;102: 3629-3636)
Little evidence of donor-derived epithelial cells in early digestive acute graft-versus-host disease
Authors: Meignin Véronique , Soulier Jean , Brau Frédéric , Lemann Marc , Gluckman Eliane , Janin Anne , Socié Gérard 
Published: July 2003

Abstract
Donor origin of epithelial intestinal cells has been studied in animals and humans after transplantation and has been used as evidence of hematopoietic stem cell (HSC) plasticity. However, in the human gastrointestinal tract, no study used X- or Y-chromosome detection by fluorescence in situ hybridization (FISH) coupled with immunologic stainings to characterize cell types on the same tissue section. Here, we combined these techniques on the same section of duodenal epithelium in 6 patients with acute graft-versus-host disease. Donor-derived lymphoid cells were detected in the epithelium and the lamina propria, as expected. However, using our stringent criteria, no donor-derived cells could be proven to be epithelial.
Imbalanced secretion of IL‐1β and IL‐1RA inChlamydia pneumoniae-infected mononuclear cells from COPD patients
Authors: Rupp J. , Kothe H. , Mueller A. , Maass M. , Dalhoff K. 
Published: July 2003

Balanced secretion of pro- and anti-inflammatory cytokines is essential in limiting pulmonary inflammation in respiratory infections. It was hypothesised that, in acute infection withChlamydia pneumoniae, mononuclear cells from chronic obstructive pulmonary disease (COPD) patients lack the opportunity to compensate for the inflammatory immune response by secreting adequate amounts of anti-inflammatory cytokines.Alveolar macrophages (AMs) and peripheral blood mononuclear cells (PBMCs) from eight COPD patients and eight healthy controls were infected withC. pneumoniaein order to determine interleukin (IL)‐1β, IL‐1 receptor antagonist (IL‐1RA) and IL‐8 expression and messenger ribonucleic acid levels.Secretion of IL‐1β was significantly enhanced in AMs (six-fold) and PBMCs (four-fold) from COPD patients after infection withC. pneumoniae. Compared to the control group, release of its anti-inflammatory counterpart IL‐1RA was diminished inCOPD patients, resulting in a significantly higher IL‐1β/IL‐1RA ratio inC.pneumoniae-infected AMs and PBMCs from COPD patients.Mononuclear cells from chronic obstructive pulmonary disease patients have less capacity for balancing the pro-inflammatory immune response caused byChlamydia pneumoniaeinfection than those from healthy controls. These findings suggest that, during acute exacerbation with intracellular pathogens, chronic obstructive pulmonary disease patients are predisposed to inflammatory changes in the lungs.
Bosentan treatment in patients with primary pulmonary hypertension receiving nonparenteral prostanoids
Authors: Hoeper M.M. , Taha N. , Bekjarova A. , Gatzke R. , Spiekerkoetter E. 
Published: July 2003

Primary pulmonary hypertension (PPH) is a life-threatening disease. Nonparenteral prostanoids,i.e.aerosolised iloprost or oral beraprost sodium show beneficial therapeutic effects but are not sufficiently active in all patients with this devastating disease. The purpose of the present study was to determine whether the endothelin-receptor antagonist bosentan is safe and effective in patients with PPH already receiving nonparenteral prostanoids.The effect of bosentan as add-on medication was studied in 20 patients with PPH, who received either inhaled iloprost (n=9) or oral beraprost (n=11) for a median period of 16±13 months, by means of the 6‐min walk test and cardiopulmonary exercise testing.After 3 months of administration of bosentan in addition to prostanoids, the walking distance in the 6‐min walk test increased by 58±43 m. Cardiopulmonary exercise testing revealed an increase in maximal oxygen consumption from 11.0±2.3 to 13.8±3.6 mL·kg−1·min−1accompanied by significant improvements in anaerobic threshold, oxygen pulse and minute ventilation/carbon dioxide production slope. Peak systolic blood pressure increased from 120±17 to 139±21 mmHg. Combination treatment was well tolerated by all patients.It is concluded that the addition of the endothelin-receptor antagonist bosentan to inhaled iloprost or oral beraprost therapy appears to be safe for patients with primary pulmonary hypertension, resulting in a marked increase in exercise capacity. Therefore, rigorous studies should address whether combination treatment is more effective than either therapeutic intervention alone.