bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical significance of CD34 expression in childhood acute lymphoblastic leukemia
Authors: Pui CH , Hancock ML , Head DR , Rivera GK , Look AT , Sandlund JT , Behm FG 
Published: October 2019

Abstract
The CD34 antigen was detected on > or = 10% of the blast cells in 235 (70%) of 335 cases of newly diagnosed childhood acute lymphoblastic leukemia (ALL) treated in two consecutive chemotherapy trials. By immunophenotype, the distribution of positive cases favored early pre-B ALL (83%; n = 180) followed by pre-B ALL (61%; n = 89) and then T-cell ALL (46%; n = 61) (P < .001). Among the B-lineage cases, CD34 expression was significantly associated with favorable presenting features: age 1 to 10 years, white race, absence of central nervous system (CNS) leukemia, low serum lactate dehydrogenase level, CD10 expression, and leukemic cell hyperdiploidy (> 50 chromosomes or DNA index > or = 1.16). Event-free survival was clearly superior for patients with CD34+ leukemia (P = .01), with an estimated 83% +/- 6% (SE) of the cohort remaining free of adverse events at 5 years post diagnosis, as compared to 63% +/- 10% of the group without this feature. Multivariate analysis showed that the prognostic influence of the antigen was independent of age, leukocyte count, and other well- recognized factors, suggesting that it would add discriminatory power to current systems of risk assignment. Findings in T-cell ALL were the reverse: CD34 expression showed positive correlations with initial CNS leukemia and CD10 negativity but not with any good-risk presenting characteristics. Log-rank analysis indicated no adverse effect on treatment outcome by CD34 antigen expression, although additional patients with need to be studied to obtain a definitive answer. The opposed clinical associations of CD34 expression in B- and T-lineage ALL may reflect fundamental biologic differences between these leukemia species.
Beta 2-integrin and L-selectin are obligatory receptors in neutrophil aggregation [see comments]
Authors: Simon SI , Rochon YP , Lynam EB , Smith CW , Anderson DC , Sklar LA 
Published: October 2019

Abstract
We have recently found that antibodies to L-selectin, the homing receptor on neutrophils, are as effective as those to beta 2-integrin at blocking formyl peptide-stimulated aggregation. Therefore, we investigated the requirements for expression of L-selectin and beta 2- integrin on adjacent cells during aggregation. Fluorescence flow cytometry allowed characterization of aggregates on the basis of size and color, as well as antibody binding to these two adhesive molecules. Formyl peptide-stimulated aggregate formation was measured for individual populations fluorescently labeled red (LDS-751) or green (CD44-FITC), and interpopulation red-green cell conjugates. Blocking either the beta 2-integrin or L-selectin adhesive epitope with monoclonal antibody on individual cell populations resulted in an approximately 50% reduction in two-color aggregation as compared with that in unblocked samples. Shedding the L-selectin on a cell population by preincubation with complexes of lipopolysaccharide and its plasma membrane binding protein also decreased aggregation to a control population by approximately 50%. We examined the aggregation of neutrophils from patients genetically deficient in beta 2-integrin and clinically leukocyte adhesion deficient (LAD). LAD adhesion to normal neutrophils was dependent on the expression of L-selectin on LAD cells and beta 2-integrin on normal cells. Thus, the minimum requirement for adhesion between two mixed populations of neutrophils was that one population expressed the beta 2-integrin and the other expressed the L- selectin adhesive epitope.
Regulation of manganese superoxide dismutase and other antioxidant genes in normal and leukemic hematopoietic cells and their relationship to cytotoxicity by tumor necrosis factor
Authors: Kizaki M , Sakashita A , Karmakar A , Lin CW , Koeffler HP 
Published: October 2019

Abstract
Myeloid cells are a major source of superoxide and other oxygen metabolites. As a protective mechanism, cells express antioxidant enzymes including manganese superoxide dismutase (Mn-SOD), copper-zinc SOD (Cu/Zn-SOD), and glutathione peroxidase (GSX-PX). Even though hematopoietic cells are a major source of oxidants, little is known of their expression of antioxidants. We found that seven myeloid leukemic cell lines blocked at different stages of differentiation constitutively expressed Mn-SOD, Cu/Zn-SOD, and GSX-PX RNAs. Level of Mn-SOD activities paralleled levels of Mn-SOD RNA. Terminal differentiation of native HL-60 cells to either granulocytes or macrophages did not alter levels of Mn-SOD RNA but markedly decreased cell division. Myeloid leukemic lines sensitive to cytotoxic effects of tumor necrosis factor (TNF) as well as normal peripheral blood lymphocytes and monocytes, dramatically increased their levels of Mn- SOD RNA in the presence of TNF. In contrast, Cu/Zn-SOD and GSX-PX RNA levels did not increase in these same cells. TNF-resistant leukemic lines had higher constitutive levels of Mn-SOD RNA and activity; and these levels did not change in the presence of TNF. Antisense but not random oligonucleotides to Mn-SOD markedly increased the sensitivity to the inhibitory effects of TNF for both the native HL-60 (TNF-sensitive) and K562 (TNF-resistant) cell lines. Further studies showed that the antisense oligonucleotides entered the cells and resulted in decreased levels of Mn-SOD RNA. The data suggest that Mn-SOD may provide protection against cytotoxicity of TNF in hematopoietic cells.
CD63 is a component of Weibel-Palade bodies of human endothelial cells
Authors: Vischer UM , Wagner DD 
Published: October 2019

Abstract
Weibel-Palade bodies are secretory granules of vascular endothelial cells specialized in the storage of von Willebrand factor (vWF) and P- selectin, two adhesion proteins that can be rapidly mobilized to the cell surface by exocytosis in response to thrombin or other agonists. In this study, we attempted to identify additional components of Weibel- Palade bodies by raising monoclonal antibodies to these granules, purified by cell fractionation. One antibody, 2C6, was found to be specific for CD63, a membrane glycoprotein previously described in the lysosomes of platelets and other cell types. The immunopurified 2C6 antigen was recognized by an anti-CD63 reference antibody, 2.28, by Western blotting. Also, the biosynthetic profile of the 2C6 antigen in endothelial cells showed a nascent molecular mass and a glycosylation pattern identical to that of CD63. Immunofluorescence staining with 2C6 showed the lysosomes, and also elongated structures identified as Weibel-Palade bodies by their shape, distribution, and positive staining with anti-vWF antibodies, CD63 was also found by Western blotting of subcellular fractions highly enriched in Weibel-Palade bodies. Our results indicate that CD63 colocalizes with vWF and P- selectin in the Weibel-Palade bodies of endothelial cells, and together with these adhesion proteins it could be rapidly expressed on the cell surface in areas of vascular injury and inflammation.
Long-term follow-up of patients with invasive fungal disease who received adjunctive therapy with recombinant human macrophage colony- stimulating factor
Authors: Nemunaitis J , Shannon-Dorcy K , Appelbaum FR , Meyers J , Owens A , Day R , Ando D , O'Neill C , Buckner D , Singer J 
Published: October 2019

Abstract
Mortality of bone marrow transplant (BMT) patients who develop invasive fungal infection is greater than 80%. Long-term follow-up of 46 consecutive BMT patients who received recombinant human macrophage colony-stimulating factor (rhM-CSF) as adjunctive therapy with standard antifungal treatment who were entered into phase I/II trials at The Fred Hutchinson Cancer Research Center is reported. rhM-CSF (100 micrograms/m2 to 2,000 micrograms/m2; Chiron/Cetus Corporation, Emeryville, CA) was administered from day 0 to 28 after determination of progressive fungal disease. Results of long-term follow-up of fungal infection, relapse, and survival were compared with 58 similar historical controls. Multivariable analysis of the patients who received rhM-CSF showed two factors that significantly correlated with poor survival: Karnofsky score < or = 20% and Aspergillus infection. Overall, survival of patients who received rhM-CSF was greater than that of historical patients (27% v 5%) and was entirely because of a 50% survival rate in patients with Candida infection and Karnofsky scores greater than 20%. Prospective, randomized, controlled trials to determine efficiency of rhM-CSF are indicated and should be directed at patients with invasive candidiasis.
Severe chronic autoimmune thrombocytopenic purpura is associated with an expansion of CD56+ CD3- natural killer cells subset [see comments]
Authors: Garcia-Suarez J , Prieto A , Reyes E , Manzano L , Merino JL , Alvarez-Mon M 
Published: October 2019

Abstract
Recent studies have indicated that autoimmune thrombocytopenic purpura (ATP) patients show immune system alterations that are not restricted to the B-cell compartment, but that also affect T lymphocytes. This report studies the phenotypic characteristics of natural killer (NK) cells in the peripheral blood of ATP patients, as well as their clinical significance in 33 ATP patients with active disease. Ten patients had stable disease (sustained platelet counts > 50,000/microL without the need for treatment), whereas 23 patients had therapy- dependent disease (platelet counts < 50,000/microL). A significant increase in both CD56+ CD3- NK cells and CD56+ CD3+ cytotoxic T lymphocytes was observed in peripheral blood mononuclear cells and in purified CD2+ cells from therapy-dependent ATP patients as compared with ATP patients with stable disease and healthy controls. Moreover, there were more major histocompatibility complex (MHC) class II molecules in the CD56+ CD3- cells from the therapy-dependent patients' peripheral blood preparations than there were in the stable ATP patients' and healthy controls' peripheral blood preparations. This growth in the number of CD56+ CD3- NK cells was statistically higher in patients whose disease was refractory to conventional therapy (corticosteroids and splenectomy). In addition to the CD56+ CD3- NK cells, the percentage of CD3+ T lymphocytes and their proliferative response to phytohemagglutinin (PHA) stimulation were studied in fresh CD2+ preparations from nine patients with stable disease, 22 patients with therapy-dependent disease, and 26 healthy controls. The proliferative response of CD2+ lymphocytes from both groups was similar and significantly defective with respect to that found in healthy controls. In conclusion, clinically severe ATP (therapy-dependent disease) is associated with a significant increase of CD56+ CD3- NK cells, which is particularly marked in patients whose disease is refractory to therapy.
Synthesis of interleukin-5 by activated eosinophils in patients with eosinophilic heart diseases
Authors: Desreumaux P , Janin A , Dubucquoi S , Copin MC , Torpier G , Capron A , Capron M , Prin L 
Published: October 2019

Abstract
Eosinophilic endomyocardial disease represents a major evolutive risk in chronic eosinophilia-associated disorders. Eosinophil granule proteins appear to be involved in cardiac injury, but the mechanisms leading to eosinophil infiltration and degranulation are not clear. Interleukin-5 (IL-5) has been recently shown to be produced by eosinophils and might play a role in both chemoattraction and degranulation of eosinophils. In four cases of eosinophilic diseases with severe cardiac failure, we evaluated the proportion of eosinophil phenotypes and the serum levels of eosinophil cationic protein (ECP) and soluble IL-2 receptor (sIL-2R), markers of disease activity in the hypereosinophilic syndromes. All four patients showed a markedly increased proportion of hypodense eosinophils with elevated serum ECP and sIL-2R levels. In all four patients, extracellular deposition of eosinophil granule proteins and features of eosinophil activation were observed in cardiac tissues. The synthesis of IL-5 by eosinophils was detected in myocardial sections and blood cells by in situ hybridization and by immunostaining with a monoclonal antibody against human IL-5. Sixty percent to 90% of tissue eosinophils expressed IL-5 mRNA and IL-5 protein. These data suggest that IL-5 can be produced by eosinophils at the sites of myocardial tissue damage and might participate in local eosinophil activation.
The cytoplasmic domain of P-selectin is phosphorylated on serine and threonine residues
Authors: Fujimoto T , McEver RP 
Published: October 2019

Abstract
P-selectin is an adhesion receptor for leukocytes that is redistributed from secretory granule membranes to the surfaces of activated platelets and endothelial cells. The cytoplasmic domain of P-selectin contains two serines, two threonines, and one tyrosine that could potentially be phosphorylated. We found that P-selectin was phosphorylated in both platelets and endothelial cells and that phosphorylation rapidly increased after cell activation. Approximately 0.02, 0.05, and 0.08 mol of phosphate/mol of P-selectin were incorporated, respectively, into resting, thrombin-activated, and phorbol ester-activated platelets. Phosphorylation was completely inhibited by the protein kinase C inhibitors, staurosporine, H-7, and chelerythrine, and was enhanced by the phosphatase inhibitors, okadaic acid and calyculin-A. Phosphoamino acid analysis of 32P-labeled P-selectin showed that phosphorylation occurred predominantly on serine with lesser amounts on threonine. When expressed in transfected Chinese hamster ovary cells, P-selectin was also phosphorylated. Mutagenesis studies showed that Ser788 was the principal site of phosphorylation, with minor sites on the other serine and threonine residues of the cytoplasmic domain. Phosphorylation may regulate membrane trafficking or other functions of P-selectin.
Detection of minimal residual disease by immunostaining of bone marrow biopsies after 2-chlorodeoxyadenosine for hairy cell leukemia
Authors: Hakimian D , Tallman MS , Kiley C , Peterson L 
Published: October 2019

Abstract
2-Chlorodeoxyadenosine (2-CdA) yields high complete remission (CR) rates in patients with hairy cell leukemia (HCL). In an effort to detect minimal residual disease, we studied two B-lineage antibodies, L26 and MB2, and a T-lineage antibody, UCHL-1, in fixed marrow core biopsies from 34 patients with HCL before and after 2-CdA. Before therapy, hairy cells exhibited intense cytoplasmic membrane reactivity with L26 and strong intracytoplasmic reactivity with MB2. UCHL-1 did not react with hairy cells. Thirty-one patients were assessable 3 months after therapy. Five of 24 (21%) patients in CR by routine evaluation had residual HCL detected by immunostaining. Four of these 5 patients have been reevaluated at 1 year. One patient relapsed by routine evaluation, 2 remained positive by immunostaining alone, and 1 patient became negative by immunostaining. A total of 19 patients have been evaluated at 1 year. Only 1 additional patient has become positive by immunostaining alone. Immunostaining using the B-lineage antibodies highlighted the presence of hairy cells with preservation of morphology. This assisted in quantifying the extent of disease, particularly when hairy cells were interstitial and blended with surrounding hematopoietic tissue, when hairy cells were present in hypocellular marrows, when hairy cells were spindle-shaped, and when marrows were markedly fibrotic. Because immunostaining can be easily performed on routinely processed marrows, it is an attractive method to detect minimal residual disease. Our data suggest that some patients in apparent CR after 2-CdA may have minimal residual disease. Patients will need to be observed prospectively to determine if residual disease will be predictive of relapse.
Competitive polymerase chain reaction to estimate the number of BCR-ABL transcripts in chronic myeloid leukemia patients after bone marrow transplantation
Authors: Cross NC , Feng L , Chase A , Bungey J , Hughes TP , Goldman JM 
Published: October 2019

Abstract
We have developed a competitive polymerase chain reaction (PCR) titration assay that estimates the number of BCR-ABL transcripts in chronic myeloid leukemia patients to monitor minimal residual disease after bone marrow transplantation (BMT). The assay gave reproducible results and allowed differences in BCR-ABL message levels of half an order of magnitude to be distinguished. Of 91 patients studied by nonquantitative PCR, 28 who had a positive PCR result on at least one occasion posttransplant were analyzed by competitive PCR. Seventeen patients had no evidence in their marrow of cytogenetic relapse during the period of observation; BCR-ABL transcript numbers in these cases ranged from approximately 10 to 800/micrograms RNA. Ten of the 11 patients who relapsed cytogenetically were studied when Philadelphia- positive metaphases were first detected in their marrow; transcript numbers ranged from 1,600 to 7 x 10(5)/micrograms RNA. Patients in hematologic relapse had between 9 x 10(4) and 10(6) BCR-ABL transcripts/micrograms RNA. Patients who progressed from cytogenetic remission to cytogenetic relapse and then to hematologic relapse had increasing numbers of BCR-ABL transcripts in their blood. Three patients had clear evidence of rising numbers of BCR-ABL transcripts before routine detection of cytogenetic relapse. Conversely patients without cytogenetic relapse generally had low or falling numbers of transcripts. We conclude that serial monitoring of residual disease post-BMT by estimating the number of BCR-ABL transcripts provides more information than conventional cytogenetics or nonquantitative PCR and may identify patients in need of therapeutic intervention before the onset of overt relapse.
Anticoagulant protein C pathway defective in majority of thrombophilic patients [see comments]
Authors: Griffin JH , Evatt B , Wideman C , Fernandez JA 
Published: October 2019

Abstract
A defect involving poor anticoagulant response to activated protein C (APC), an anticoagulant serine protease known to inactivate factors Va and VIIIa in plasma, was recently reported and the existence of a novel APC cofactor was suggested. To define the frequency of this defect among 25 venous thrombophilic patients with no identifiable laboratory test abnormality and among 22 patients previously identified with heterozygous protein C or protein S deficiency, the APC-induced prolongation of the activated partial thromboplastin time assay for these patients was compared with results for 35 normal subjects. The results show that this new defect in anticoagulant response to APC is surprisingly present in 52% to 64% of the 25 patients, ie, in the majority of previously undiagnosed thrombophilia cases, but is not present in 20 of 22 heterozygous protein C or protein S deficient patients, suggesting that the new factor is a risk factor independent of protein C or protein S deficiency. The results demonstrate that abnormalities in the anticoagulant protein C pathway are present in the majority of thrombophilic patients.
Human fibrinogen polymorphic site analysis by restriction endonuclease digestion and allele-specific polymerase chain reaction amplification: identification of polymorphisms at positions A alpha 312 and B beta 448
Authors: Baumann RE , Henschen AH 
Published: October 2019

Abstract
In the fibrinogen molecule, a total of seven sites have been tentatively identified as polymorphic; however, disagreements about these sites have been observed among the various protein and DNA sequence data published. To allow examination of the potential polymorphic sites at the DNA level, human genomic DNA samples were prepared from 110 unrelated, healthy individuals. Either allele- specific polymerase chain reaction (ASPCR) amplification or PCR amplification followed by restriction endonuclease digestion was used to detect the presence of possible polymorphisms. Two polymorphic sites were confirmed, one at A alpha 312 (Thr/Ala) by RsaI restriction analysis, and a second at B beta 448 (Arg/Lys) by MnlI restriction analysis. Mendelian inheritance of both polymorphisms was demonstrated and allele frequencies were estimated as 0.76/0.24 and 0.85/0.15 for the A alpha 312 and B beta 448 sites, respectively. The sites at A alpha 47, A alpha 296, B beta 162, B beta 296, and gamma 88 showed no evidence of variation in any of our samples. The amino acid polymorphisms at A alpha 312 and B beta 448 reflect conservative residue changes with unknown effects on fibrinogen structure or function. An additional, previously unrecognized DNA sequence variant was detected in a single individual in the second intron of the A alpha chain using HinfI restriction analysis.
Immunologic analysis of the cloned platelet thrombin receptor activation mechanism: evidence supporting receptor cleavage, release of the N-terminal peptide, and insertion of the tethered ligand into a protected environment
Authors: Norton KJ , Scarborough RM , Kutok JL , Escobedo MA , Nannizzi L , Coller BS 
Published: October 2019

Abstract
The recently cloned functional thrombin receptor is thought to be activated by thrombin cleavage of the bond between R41 and S42, followed by the insertion of the new N-terminal region (“tethered ligand”) into an unknown site in the receptor. Antibodies to peptides at or near the cleavage site have been reported to inhibit thrombin- induced platelet activation to varying extents, but the precise mechanism(s) of their inhibition is unknown. We have produced: (1) a polyclonal antibody in rabbits to a peptide containing amino acids 34 to 52 (anti-TR34–52); enzyme-linked immunosorbent assays (ELISA) indicate that anti-TR34–52 contains antibodies to regions on both sides of the thrombin cleavage site; (2) two murine monoclonal antibodies (MoAbs) to a peptide containing amino acids 29 to 68; one antibody reacts primarily with residues N-terminal to the thrombin cleavage site, and the other reacts primarily with residues C-terminal to the cleavage site; and (3) a polyclonal rabbit antibody to a peptide containing amino acids 83 to 94 (anti-TR83–94). Anti-TR34–52 binds to platelets as judged by flow cytometry, and pretreating platelets with a thrombin receptor peptide ligand does not lead to loss of antibody reactivity, suggesting that platelet activation does not initiate redistribution or internalization of surface thrombin receptors. In contrast, pretreating platelets with thrombin leads to complete loss of anti-TR34–52 binding. Similarly, the binding of both MoAbs to platelets is dramatically reduced by pretreatment with thrombin. However, the binding of anti-TR83–94 is not decreased by thrombin activation, confirming that the receptor is not internalized. Anti-TR34–52 profoundly inhibits low dose thrombin-induced platelet shape change and aggregation, but the inhibition can be overcome with higher thrombin doses. However, anti-TR34–52 does not inhibit platelet aggregation induced by tethered ligand peptides. The TR34–52 peptide is a thrombin substrate, with cleavage occurring at the R41-S42 bond as judged by high performance liquid chromatography (HPLC) and platelet aggregation analysis. Anti-TR34–52 prevented cleavage of the TR34–52 peptide, suggesting that the antibody prevents platelet activation, at least in part, by preventing cleavage of the thrombin receptor. These data, although indirect, provide additional support for a thrombin activation mechanism involving thrombin cleavage of the receptor; in addition, they provide new evidence indicating that receptor cleavage is followed by loss of the N-terminal peptide, and insertion of the tethered ligand into a protected domain.