bluuebunny/crossref_metadata_2025_split huggingface dataset:
Native associations of early hematopoietic stem cells and stromal cells isolated in bone marrow cell aggregates
Authors: Funk PE , Kincade PW , Witte PL 
Published: October 2019

Abstract
In suspensions of murine bone marrow, many stromal cells are tightly entwined with hematopoietic cells. These cellular aggregations appear to exist normally within the marrow. Previous studies showed that lymphocytes and stem cells adhered to stromal cells via vascular cell adhesion molecule 1 (VCAM1). Injection of anti-VCAM1 antibody into mice disrupts the aggregates, showing the importance of VCAM1 in the adhesion between stromal cells and hematopoietic cells in vivo. Early hematopoietic stem cells were shown to be enriched in aggregates by using a limiting-dilution culture assay. Myeloid progenitors responsive to WEHI-3CM in combination with stem cell factor (c-kit ligand) and B220- B-cell progenitors responsive to insulin-like growth factor-1 in combination with interleukin-7 are not enriched. We propose a scheme of stromal cell-hematopoietic cell interactions based on the cell types selectively retained within the aggregates. The existence of these aggregates as native elements of bone marrow organization presents a novel means to study in vivo stem cell-stromal cell interaction.
Differential effects of anti-tumor necrosis factor monoclonal antibodies on systemic inflammatory responses in experimental endotoxemia in chimpanzees
Authors: van der Poll T , Levi M , van Deventer SJ , ten Cate H , Haagmans BL , Biemond BJ , Buller HR , Hack CE , ten Cate JW 
Published: October 2019

Abstract
Tumor necrosis factor (TNF) is considered to be a pivotal mediator of endotoxin-induced lethality. To assess the intermediate role of TNF in specific systemic inflammatory responses known to contribute to tissue injury in endotoxemia, eight healthy adult chimpanzees were intravenously injected with Escherichia coli endotoxin (4 ng/kg). In four of these animals the administration of endotoxin was followed immediately by a bolus intravenous injection of an anti-TNF monoclonal antibody (15 mg/kg). Treatment with anti-TNF completely prevented the endotoxin-induced increase in serum TNF activity, and profoundly reduced the appearance of interleukin-6 and -8 (both P < .05). Neutrophilia and lymphopenia were not affected by anti-TNF, whereas neutrophil degranulation, as measured by the plasma concentrations of elastase-alpha 1-antitrypsin complexes, was only slightly reduced (peak levels after endotoxin alone 31.0 +/- 3.4 ng/mL, versus 25.5 +/- 3.4 ng/mL after endotoxin with anti-TNF; P < .05). Anti-TNF did not influence endotoxin-induced activation of the coagulation system, as reflected by unchanged increases in the plasma concentrations of the prothrombin fragment F1 + 2 and thrombin-antithrombin III complexes. In contrast, anti-TNF strongly attenuated the activation of the fibrinolytic system, ie, peak plasma levels of plasmin-alpha 2- antiplasmin were 33.8 +/- 11.1 nmol/L after endotoxin alone and 17.0 +/- 2.9 nmol/L after endotoxin with anti-TNF (P < .05). These results suggest that TNF is not the common mediator of systemic inflammatory changes in low-grade endotoxemia. Moreover, the finding that in this mild model anti-TNF specifically inhibited fibrinolysis suggests that treatment with anti-TNF potentially may enhance the tendency towards microvascular thrombosis in sepsis.
Autosomal recessive chronic granulomatous disease with absence of the 67-kD cytosolic NADPH oxidase component: identification of mutation and detection of carriers
Authors: de Boer M , Hilarius-Stokman PM , Hossle JP , Verhoeven AJ , Graf N , Kenney RT , Seger R , Roos D 
Published: October 2019

Abstract
Chronic granulomatous disease (CGD) is characterized by the failure of phagocytic leukocytes to kill certain bacteria and fungi. This is caused by deficiencies in one of the components of NADPH oxidase, the enzyme in phagocytic leukocytes that generates superoxide. In a rare, autosomal recessive form of CGD, a 67-kD cytosolic component of NADPH oxidase (p67-phox) is missing. Until now, mutations in the gene coding for this protein have not been identified. We now report on a 10-year- old girl with lymph node and liver abscesses who was recognized as an A67(0) CGD patient by lack of NADPH oxidase activity in her granulocytes, a cytosolic defect in a cell-free oxidase system, and lack of immunoreactive material with an antiserum against the p67-phox protein. mRNA for this protein was present in normal amounts in her monocytes. This p67-phox mRNA was reverse-transcribed, and the coding region was amplified by polymerase chain reaction in six overlapping fragments and was sequenced. The patient appeared to be homozygous for a G-233-->A mutation, resulting in a nonconservative amino acid change (78Gly-->Glu). This mutation was also found in the genomic DNA of this patient but not in that of 38 normal donors. Both parents and a sister proved to be carriers of the disease, as deduced from the mutation in only one allele. The carrier state was also manifested by intermediate superoxide production by their intact granulocytes and in the cell-free system.
Serum erythropoietin and erythropoiesis in high- and low-fetal hemoglobin beta-thalassemia intermedia patients
Authors: Galanello R , Barella S , Turco MP , Giagu N , Cao A , Dore F , Liberato NL , Guarnone R , Barosi G 
Published: October 2019

Abstract
Clinical data suggest that in beta-thalassemia-intermedia patients, higher levels of circulating fetal hemoglobin (HbF) are associated with greater disease severity at comparable degrees of anemia. We assessed the influence of the amount of circulating HbF on serum erythropoietin (s-Epo) levels and on serum transferrin receptor, a measure of erythropoiesis, in 30 beta-thalassemia-intermedia patients. Twenty-four showed more than 40% HbF (21 of whom with beta (0)-thalassemia) and 6 presented lower HbF levels (beta(+)-thalassemia). The two groups of patients did not differ in age (15.3 v 19 years, respectively) or degree of anemia (Hb = 8.8 g/dL in both groups). Log (s-Epo) was correlated inversely with Hb (r = -0.47; P < .01), and directly with HbF (r = .55; P < .001). Multivariate regression analysis showed that Hb and HbF were independently correlated with s-Epo levels. High-HbF patients had greater s-Epo values at the same Hb level than low-HbF patients. Considering that iron-deficiency anemia control patients represented the predicted physiologic response of s-Epo to anemia, the observed/predicted s-Epo ratio in low-HbF thalassemic patients was no different from controls, but was increased in the high-HbF group. High- HbF patients also showed an expansion of erythropoiesis as much as four to nine times the normal value at the same Hb level as low-HbF patients. We conclude that HbF exerts an independent regulatory effect on erythropoietin production and erythropoiesis that is detectable only when HbF levels exceed 40%.
Granulocyte-macrophage colony-stimulating factor augmentation of T-cell receptor-dependent and T-cell receptor-independent thymocyte proliferation
Authors: Stewart-Akers AM , Cairns JS , Tweardy DJ , McCarthy SA 
Published: October 2019

Abstract
The effects of granulocyte-macrophage colony-stimulating factor (GM- CSF) are not confined to cells of the myeloid lineage. GM-CSF has been shown to have effects on mature T cells and both mature and immature T- cell lines. We therefore examined the GM-CSF responsiveness of murine thymocytes to investigate whether GM-CSF also affected normal immature T lymphocytes. The studies presented here indicate that GM-CSF augments accessory cell (AC)-dependent T-cell receptor (TCR)-mediated proliferation of unseparated thymocyte populations. To identify the GM- CSF responsive cell type, thymic AC and T cells were examined for GM- CSF responsiveness. We found that GM-CSF augmentation of TCR-induced thymocyte proliferation appears to be mediated via augmentation of AC function, and not via direct effects on mature single-positive (SP) thymocytes. Enriched double-negative (DN) thymocytes were also tested for GM-CSF responsiveness. GM-CSF induced the proliferation of adult and fetal DN thymocytes in an AC-independent and TCR-independent single- cell assay. Thus, in contrast to the SP thymocytes, a DN thymocyte population was directly responsive to GM-CSF. GM-CSF therefore may play a direct role in the expansion of DN thymocytes and an indirect role in the expansion of SP thymocytes.
Identification of masked polycythemia vera from patients with idiopathic marked thrombocytosis by endogenous erythroid colony assay
Authors: Shih LY , Lee CT 
Published: October 2019

Abstract
We used the methylcellulose-culture technique to determine the utility of the erythroid progenitor growth in vitro from nonadherent T-depleted bone marrow and peripheral blood cells in distinguishing polycythemia vera (PV) from essential thrombocythemia. Thirty patients with PV (group A) and 30 patients who presented with idiopathic marked thrombocytosis with platelet count greater than 1,000 x 10(9)/L and a normal or reduced hemoglobin (Hb) level (group B) were studied at initial presentation. Endogenous (erythropoietin-independent) erythroid colonies (EEC) were found in all patients in group A and 13 in group B. The numbers of EEC were comparable between patients in group A and the 13 patients with EEC in group B, 11 of whom with initial Hb levels ranging between 6.4 g/dL and 12.6 g/dL were found to have PV 2 to 45 months after initial evaluation. The number of EEC did not correlate with the time to the progression of polycythemia, whereas myelosuppression delayed the subsequent development of PV. Of the two patients with EEC in group B who did not develop PV, both received chemotherapy soon after presentation, which might preclude the evidence of polycythemia evolution. None of the other patients in group B who did not form EEC developed PV with a median follow-up of 24 months. This study indicates that the assessment of EEC in bone marrow or blood is helpful in early identification of PV or prediction of polycythemia evolution in patients with marked thrombocytosis in whom polycythemia has been initially masked or anemia is present.
In vivo expression of the B7 costimulatory molecule by subsets of antigen-presenting cells and the malignant cells of Hodgkin's disease
Authors: Munro JM , Freedman AS , Aster JC , Gribben JG , Lee NC , Rhynhart KK , Banchereau J , Nadler LM 
Published: October 2019

Abstract
The B-lymphocyte/accessory-cell activation antigen B7 (BB1) has been shown in vitro to stimulate T-lymphocyte proliferation and cytokine production via CD28 present on the latter cells. In this study, benign lymphoid tissues, lymphomas, and extralymphoid inflammatory sites were examined immunohistochemically using anti-B7 and other relevant monoclonal antibodies. B7 was expressed by benign transformed germinal center B cells, as it was by B cells of follicular lymphomas. B7 was also expressed by a subpopulation (a mean of 31% to 65%) of macrophages and dendritic cells in a variety of lymphoid tissues. It was present in abundance on all macrophages constituting sarcoid granulomas in lymph nodes. In extralymphoid inflammation, 17% to 35% of macrophages expressed B7 only weakly. Cases of Hodgkin's disease showed expression of B7 by the majority of Reed-Sternberg cells or malignant mononuclear variants, a phenomenon that potentially contributes to the lymphocytic accumulation that is a feature of this condition. CD28+ T cells were seen in all areas where T cells were present. B7+ and CD28+ cells colocalized in, for example, lymphoid follicles, lymph node paracortex, sarcoid granulomas, and Hodgkin's disease tissue, indicating a potential for cellular interaction via these molecules at these sites.
A cautionary note regarding hydroxyurea in sickle cell disease
Authors: Vichinsky EP , Lubin BH 
Published: October 2019

Abstract
Hydroxyurea can increase fetal hemoglobin (HbF) and improve the clinical course of sickle cell disease (SCD) patients. However, several issues of hydroxyurea therapy remain unresolved, including differences in patients' drug clearance, predictability of drug response, reversibility of sickle cell disease-related organ damage by hydroxyurea, and the efficacy of elevated HbF. We treated two patients with hydroxyurea for periods of 1 to 4 years, monitoring clinical course and laboratory parameters at regular intervals. The first patient (patient A) had a history of chronic pain and extensive hospitalizations. The second patient (patient B) had a history of stroke and refused to continue with chronic transfusion therapy and chelation. Both patients showed a fivefold to tenfold increase in HbF (5% to 25%, 3% to 31%). However, patient A developed an acute chest syndrome, despite an HbF level of 20%. After red blood cell transfusions for hypoxia, the HbF level decreased to 5%. When hydroxyurea dosage was increased, pancytopenia developed and was not resolved until 2 months after hydroxyurea was discontinued; Patient B developed a cerebral hemorrhage on hydroxyurea; he died shortly thereafter. His HbF level was 21% before death. We noted an increase in HbF and a general improvement in the two patients. However, both experienced major SCD-related complications despite HbF levels over 20%. Our findings also suggest that the progressive vascular changes associated with SCD are unlikely to be dramatically affected by increased HbF levels. Because neither the efficacy nor the toxicity of hydroxyurea have been thoroughly investigated, physicians should be cautious in prescribing hydroxyurea for patients with SCD before completion of the National Clinical Trial.
Stem cell factor and basic fibroblast growth factor are synergistic in augmenting committed myeloid progenitor cell growth
Authors: Gabrilove JL , White K , Rahman Z , Wilson EL 
Published: October 2019

Abstract
Stem cell factor (SCF) and basic fibroblast growth factor (bFGF) are hematopoietic cytokines produced by bone marrow stromal cells. It is known that, although SCF and bFGF have limited clonogenic activity on their own, they can augment colony-stimulating factor (CSF)-mediated progenitor cell growth. Because these factors are both sequestered by stromal cells, we examined their interaction on progenitor cell growth in conjunction with granulocyte-macrophage-CSF (GM-CSF). In this study, we show that clonogenic growth derived from low-density bone marrow cells stimulated by GM-CSF is significantly augmented (P < .001) in the presence of maximal (100 ng/mL) concentrations of SCF in combination with 100 ng/mL of bFGF. When CD34+ cells are used, the synergistic effect of bFGF and SCF for GM-CSF-mediated progenitor cell growth is further increased, resulting in as much as a sevenfold increase in detectable colony-forming units granulocyte-macrophage (P < .001). These data suggest that the synergistic activity of bFGF and SCF is mediated directly on hematopoietic precursors. These observations suggest that bFGF and SCF, concentrated locally on stromal cell surfaces, might interact in concert with other hematopoietic cytokines to regulate stem cell proliferation and differentiation in hematopoietic niches in the bone marrow.
Signaling and induction of enhanced cytoadhesiveness via the hematopoietic progenitor cell surface molecule CD34
Authors: Majdic O , Stockl J , Pickl WF , Bohuslav J , Strobl H , Scheinecker C , Stockinger H , Knapp W 
Published: October 2019

Abstract
The transmembrane glycoprotein CD34 shows a highly restricted expression on a crucial subset of hematopoietic cells. We show here that engagement of particular determinants of CD34 can lead to signal transduction and to enhanced adhesiveness of CD34+ hematopoietic cells. Monoclonal antibodies (MoAbs) directed against O-sialoglycoprotease- sensitive epitopes of CD34 (QBEND10, ICH3, BI.3C5, MY10) but not MoAbs against O-sialoglycoprotease-resistant epitopes (9F2, 8G12) induce actin polymerization in KG-1a and KG-1 cells and strongly enhanced cytoadhesiveness. The capacity to induce adhesion requires cellular energy, divalent cations, and intact cytoskeleton but not de novo protein synthesis. The observed cytoadhesion seems at least in part to be caused by a concomitant activation of the beta 2 integrin cytoadhesion pathway. It can be significantly inhibited with lymphocyte function-associated antigen-1 and intercelluar adhesion molecule-1 antibodies. Protein kinase inhibition analyses suggest that the pathways initiated by engagement of the CD34 molecule with certain CD34 MoAbs involves protein tyrosine kinases but that protein kinase C is not critically involved.
Evidence for separate calcium-signaling P2T and P2U purinoceptors in human megakaryocytic Dami cells
Authors: Murgo AJ , Contrera JG , Sistare FD 
Published: October 2019

Abstract
Recently (J Pharmacol Exp Ther 261:580, 1992), we have shown that K562 leukemia cells express a calcium-signaling purinoceptor with characteristics of the P2T receptor subtype for adenosine diphosphate (ADP) previously found only in platelets. Because these results suggested that the P2T receptor may be an early marker for megakaryocytic differentiation, we studied whether this calcium- signaling receptor is also expressed in Dami cells, a human megakaryocytic leukemia cell line. Here we report evidence that Dami cells express a P2T receptor for ADP. The calcium response EC50 values for ADP, 2-methylthioadenosine diphosphate (2-MeS-ADP), and adenosine 5′-O-(2-thiodiphosphate) (ADP beta S) in Dami cells are 0.4 mumol/L, 0.04 mumol/L, and 2 mumol/L, respectively, which approximate the potencies of these agonists in K562 cells and in platelets. The platelet P2T receptor antagonists 2-methylthioadenosine triphosphate (2- MeS-ATP), and 2-chloroadenosine triphosphate (2-Cl-ATP) were surprisingly potent agonists at the P2T receptor in both Dami and K562 cells. Dami cells, unlike K562 cells and platelets, also respond to adenosine triphosphate (ATP) and uridine triphosphate (UTP) with an increase in intracellular calcium. Adenosine monophosphate (AMP) is an effective antagonist of the response to ADP, 2-MeS-ADP, ADP beta S, 2- MeS-ATP, and 2-Cl-ATP, but not to ATP and UTP. The responses to maximal concentrations of UTP in combination with either ADP, 2-MeS-ADP, ADP beta S, or 2-MeS-ATP are additive. In contrast, ADP in combination with either 2-MeS-ADP, ADP beta S, 2-MeS-ATP, or 2-Cl-ATP are not additive. UTP desensitized Dami cells to ATP but not to ADP, 2-MeS-ADP, ADP beta S, or 2-MeS-ATP. Addition of ATP after UTP desensitization antagonized subsequent responsiveness to ADP. The data suggest that the receptor for ADP may be a unique P2T subtype, and the receptor for ATP and UTP is distinct from that of ADP and is most characteristic of the P2U (nucleotide) receptor subtype. Activation of either the P2T or P2U receptor causes a rapid generation of inositol trisphosphate in Dami cells.
Characterization of a monoclonal IgMK (IgMGAS) anti-Gd cold agglutinin (CA). Its coexistence with a monoclonal IgG3K (IgGGAS) without CA activity that might be clonally related to IgMGAS
Authors: De la Fuente MA , Egile C , Pereira A , Juan M , Vivanco F , Roelcke D , Dighiero G , Gallart T 
Published: October 2019

Abstract
A monoclonal IgMK (IgMGAS) cold agglutinin (CA) of the infrequent anti- Gd specificity, found in a patient with Waldenstrom macroglobulinemia, has been characterized. IgMGAS uses a VH gene homologous (93.7%) to the reported VH251 germ-line, one of the two functional genes of the VH5 family, with differences in both framework regions and complementary determining regions (CDR). The VL gene is homologous to the reported 15AVK1 germ-line gene, recently described in an anti-i CA, with differences mostly clustered in CDR. In the patient's serum, IgMGAS coexisted with a monoclonal IgG3K (IgGGAS) that lacked CA activity but expressed the private idiotopes found on IgMGAS. Both Ig lacked reactivity with antibodies detecting VH1 or VHIII or VKIII subgroup regions or the VH4–21 gene product that is expressed by anti-I/i CAs. The K chains from both Igs showed the same isoelectrical mobility. Moreover, the k chains from both serum Igs showed the same N-terminal amino acid sequence. This sequence was identical to that predicted by the nucleotide sequence of VK1GAS gene segment, including one discrepancy at position 15 (Ile for Val) with respect to the consensus VK1 subgroup regions. Although these data do not exclude a possible independent clonal origin, they are consistent with the notion that IgGGAS might be clonally related to IgMGAS.
The function of c-fms in hairy-cell leukemia: macrophage colony- stimulating factor stimulates hairy-cell movement
Authors: Burthem J , Baker PK , Hunt JA , Cawley JC 
Published: October 2019

Abstract
Hairy cells (HCs) and some activated B cells express high levels of macrophage colony-stimulating factor (M-CSF) (CSF-1) receptor, but the functional effects of the cytokine on B cells have not been previously identified. Using video microscopy, image analysis, and migration assays, M-CSF was shown to induce chemokinetic and chemotactic movement of HCs. This movement response involved transition to a highly mobile, rounded cell form and was accompanied by distinctive changes in F-actin polymerization and distribution. Furthermore, the M-CSF-induced motility was substantially modified by the adhesive protein used as a substratum and involved qualitative changes in the function of the alpha v beta 3 integrin of HCs. It is suggested that the findings are relevant to the pathophysiology of hairy-cell leukemia (HCL) in particular, and to the biology of B-cell migration in general.
Isolation and characterization of gelatinase granules from human neutrophils
Authors: Kjeldsen L , Sengelov H , Lollike K , Nielsen MH , Borregaard N 
Published: October 2019

Abstract
We recently confirmed the existence of gelatinase granules as a subpopulation of peroxidase-negative granules by double-labeling immunogold electron microscopy on intact cells and by subcellular fractionation. Further characterization of gelatinase granules has been hampered by poor separation of specific and gelatinase granules on both two-layer Percoll gradients and sucrose gradients. We have developed a three-layer Percoll density gradient that allows separation of the different granules and vesicles from human neutrophils; in particular, it allows separation of specific and gelatinase granules. This allows us to characterize these two granule populations with regard to their content of membrane proteins, which become incorporated into the plasma membrane during exocytosis. We found that gelatinase granules, defined as peroxidase-negative granules containing gelatinase but lacking lactoferrin, contain 50% of total cell gelatinase, with the remaining residing in specific granules. Furthermore, we found that 20% to 25% of both the adhesion protein Mac-1 and the NADPH-oxidase component cytochrome b558 is localized in gelatinase granules. Although no qualitative difference was observed between specific granules and gelatinase granules with respect to cytochrome b558 and Mac-1, stimulation of the neutrophil with FMLP resulted in a selective mobilization of the least dense peroxidase-negative granules, ie, gelatinase granules, which, in concert with secretory vesicles, furnish the plasma membrane with Mac-1 and cytochrome b558. This shows that gelatinase granules are functionally important relative to specific granules in mediating early inflammatory responses.