bluuebunny/crossref_metadata_2025_split huggingface dataset:
Binding of fibrin fragments to one-chain and two-chain tissue-type plasminogen activator
Authors: Hasan AA , Chang WS , Budzynski AZ 
Published: October 2019

Abstract
To explore whether fibrin fragments have binding affinity for the tissue-type plasminogen activator (t-PA) molecule, the interactions were studied of (DD)E complex and fragments DD, E1, and E3 with one- chain and two-chain t-PA. For this purpose, a solid-phase binding assay was developed using microtiter plates with nitrocellulose filters. It was found that (DD)E complex and fragments DD and E3 retained the t-PA binding function of the parent fibrin molecule, thus demonstrating that t-PA binds to both the D and E domains of fibrin. Unexpectedly, fragment E1 did not bind t-PA. Fibrin fragments had different binding properties for one-chain and two-chain t-PA. (DD)E complex had the highest and fragment E3 the lowest affinity for one-chain t-PA, both binding curves being consistent with one class of binding sites. However, binding of the fragments with two-chain t-PA was distinguished by more than one class of binding sites, with fragment E3 having the highest affinity for this form of the activator. epsilon-Aminocaproic acid, even at 50 mmol/L concentration, had only minimal effect on binding of (DD)E complex or fragment DD to either one-chain or two- chain t-PA. The potentiating effect of fibrin fragments on plasminogen activation by t-PA was measured by a chromogenic substrate assay. Fragment DD was the most effective stimulator of plasminogen activation by t-PA. In conclusion, (DD)E complex and fragment DD retained most of the regulatory functions of fibrin, which included t-PA binding and t- PA-mediated acceleration of plasminogen activation to plasmin.
Frequent mutations in the p53 gene in human myeloid leukemia cell lines
Authors: Sugimoto K , Toyoshima H , Sakai R , Miyagawa K , Hagiwara K , Ishikawa F , Takaku F , Yazaki Y , Hirai H 
Published: October 2019

Abstract
The p53 gene is currently considered to function as a tumor-suppressor gene in various human malignancies. In hematologic malignancies, alterations in the p53 gene have been shown in some human leukemias and lymphomas. Although mutations in the p53 gene are infrequent in acute myelogenous leukemia (AML) patients, we show in this report that alterations in the p53 gene are frequent in myeloid leukemia cell lines. We studied alterations of the p53 gene in nine human myeloid leukemia cell lines by reverse transcriptase-polymerase chain reaction (RT-PCR), single-strand conformation polymorphism (SSCP) analysis, and direct sequencing. Expression of the p53 gene was not detected at all by RT-PCR in two of the nine cell lines. In these two cell lines, Southern blot analysis showed gross rearrangements and deletions in both of the p53 alleles. Six of the nine cell lines were found to express only mutant p53 mRNA by RT-PCR/SSCP analysis and direct sequencing, and wild-type p53 mRNA was not detected. Two of the mutant p53 mRNAs were shown to be products of abnormal splicing events induced by intronic point mutations. Taken together, eight of nine human myeloid leukemia cell lines expressed no or an undetectable amount of wild-type p53 mRNA. Three of the eight cell lines were growth factor- dependent. Our results suggest that inactivation of the p53 gene may be a common feature in myeloid leukemia cell lines and may play an important role in the establishment of these cell lines.
Expression of lymphoid-associated cell surface antigens by childhood acute myeloid leukemia cells lacks prognostic significance
Authors: Smith FO , Lampkin BC , Versteeg C , Flowers DA , Dinndorf PA , Buckley JD , Woods WG , Hammond GD , Bernstein ID 
Published: October 2019

Abstract
The prognostic significance of cell surface antigens associated with lymphoid and myeloid lineage differentiation on the blasts of children with acute myeloid leukemia (AML) was evaluated. Leukemic blasts from 176 patients enrolled on Childrens Cancer Study Group Protocol 213 determined to have AML by standard morphologic and cytochemical criteria were immunophenotyped. Cell surface antigens associated with myeloid differentiation were found on blasts from 88.1% of patients (CD15, 44%; CD33, 65%; CD36, 53%; glycoprotein Ib, 9.3%). However, blasts from 30.7% of patients expressed surface antigens thought to be specific for lymphoid lineage differentiation (CD2, 9.4%; CD5, 2.7%; CD19, 34.5%; CD20, 0.8%). In addition, CD34, a glycoprotein found on immature cells of both myeloid and lymphoid lineages, was expressed on the blast cells of 48.2% of patients. With the exception of the lymphoid lineage nonspecific antigen CD4, no correlation was found between white blood cell count at diagnosis, age, and French-American- British morphology, and the expression of any of the lymphoid- or myeloid-associated cell surface antigens studied. Nor was the expression of these antigens prognostically significant with respect to response to induction therapy, death during induction, survival, event- free survival, or survival/event-free survival following remission induction. Multivariate analysis showed that CD4 expression was not an independent predictor of outcome. Thus, this prospective study suggests that expression of lymphoid-associated cell surface antigens as well as myeloid-associated antigens by childhood AML blasts lacks prognostic significance.
Reconstitution of defective respiratory burst activity with partially purified human neutrophil cytochrome B in two genetic forms of chronic granulomatous disease: possible role of Rap1A
Authors: Quinn MT , Curnutte JT , Parkos CA , Mullen ML , Scott PJ , Erickson RW , Jesaitis AJ 
Published: October 2019

Abstract
Neutrophil plasma membranes from patients with the X-linked and autosomal recessive forms of chronic granulomatous disease (CGD) that lack cytochrome b are incapable of generating superoxide anion (O2-) in vivo and in vitro. The O2- generating activity of these defective membranes was reconstituted with the addition of partially purified human neutrophil cytochrome b in a detergent-based, cell-free activation system. Depending on the detergent system used, 50% to 100% of the activity of control membranes was recovered, and this activity was directly dependent on the cytochrome b concentration. However, when cytochrome b was purified to 99% homogeneity, the reconstitutive capacity of the cytochrome was lost, possibly because of subtle denaturation of the cytochrome or the removal of an additional required cofactor. Examination of the latter possibility with respect to a protein known to coassociate with the cytochrome, ie, Rap1A, indicated that this ras-like protein was present in the partially purified cytochrome preparation used to reconstitute activity in CGD membranes, but was missing in the highly purified preparation. However, the finding that Rap1A was present in normal amounts in the neutrophil membranes from all four major types of CGD (including those missing cytochrome b) suggested that the conditions required of the reconstitution assay did not favor the reassociation of the membrane- derived Rap1A with exogenously added cytochrome b or that another unidentified membrane component was lost during the final purification step. The normal expression of Rap1A in CGD cell membranes also indicates that this protein is not responsible for the absence of O2- production in the X-linked and autosomal recessive cytochrome b- negative forms of CGD. Finally, these results show that the expression of Rap1A in the plasma membrane is not dependent on the coordinate expression of cytochrome b, despite the close association shown for these two proteins in the normal cell membrane.
Is 600 mg/m2 the appropriate dosage of busulfan in children undergoing bone marrow transplantation?
Authors: Vassal G , Deroussent A , Challine D , Hartmann O , Koscielny S , Valteau-Couanet D , Lemerle J , Gouyette A 
Published: October 2019

Abstract
Recent studies have reported that the pharmacokinetics of high-dose busulfan in bone marrow transplantation (BMT) are age-dependent: with the usual dosage of 16 mg/kg over 4 days, systemic exposure is two to four times lower in children than in adults. Data suggested that the dose of busulfan should rather be calculated on the basis of the body surface area (BSA). We measured plasma pharmacokinetics of busulfan in 27 children (mean age, 5.4 years) who were administered a new dosage of 600 mg/m2 over 4 days, ie, 17.8 to 29.2 mg/kg (mean, 24.8 mg/kg), using a gas chromatography-mass spectrometry assay. Our results demonstrate that, with this new dosage, systemic exposure is significantly increased in children compared with that achieved with the usual dosage of 16 mg/kg (6,404 +/- 2,378 v 3,918 +/- 1,170 ng.h/mL; P = .003). Moreover, there is no longer a significant difference in systemic exposure between children treated with this new dosage and adults given a dose of 16 mg/kg of busulfan. However, despite the use of a dosage normalized to the BSA, there is still a wide interindividual variation in systemic exposure, ranging from 3,566 to 13,129 ng.h/mL, which may account for the high incidence of venoocclusive disease (VOD) of the liver that we have already reported. The optimal dosage and schedule of busulfan in children requires a more individual approach that could be based on dose adjustment and plasma level monitoring.
Support of human cord blood progenitor cells on human stromal cell lines transformed by SV40 large T antigen under the influence of an inducible (metallothionein) promoter
Authors: Cicuttini FM , Martin M , Salvaris E , Ashman L , Begley CG , Novotny J , Maher D , Boyd AW 
Published: October 2019

Abstract
We describe the development of a human bone marrow (BM) culture system which allows study of the interaction of stromal cell lines (SCL) and highly purified hematopoietic progenitor cells. Normal BM stromal cells were electroporated with a plasmid containing the simian virus 40 (SV40) large T antigen (SV40 T Ag) under the control of a synthetic metallothionein promoter (MT4); this construct is designated MT4 SV40 T Ag. SCL in which the rate of proliferation could be controlled by altering the zinc (Zn) concentration were characterized, demonstrating that the SCL were heterogeneous with respect to G-CSF and GM-CSF production. Suppression of SCL proliferation on removal of Zn made it possible to use these lines in coculture with purified CD34+ progenitor cells from umbilical cord blood. The ability to control proliferation of SCL has allowed us to maintain the survival and expansion of colony- forming cells in culture for up to 2 months. These lines have enabled us to test for stromal cell characteristics at a clonal level and provided us with a tool to analyze the events leading to lineage commitment and hematopoietic differentiation, as demonstrated by suppression of hematopoiesis by an antibody directed against the c-kit molecule.
Protein C deficiency Hong Kong 1 and 2: hereditary protein C deficiency caused by two mutant alleles, a 5-nucleotide deletion and a missense mutation
Authors: Sugahara Y , Miura O , Yuen P , Aoki N 
Published: October 2019

Abstract
We characterized a mutant protein C gene from an individual with no detectable protein C antigen in blood plasma. Southern blot hybridization analysis with human protein C cDNA demonstrated neither gross deletion nor rearrangement of the gene. Sequencing all the exons and exon-intron boundaries of the gene except the 3′ noncoding region showed two mutant alleles. The one, derived from the mother, represents a deletion of 5 nucleotides (nt) (CCCGC) in the end of exon VI (mutation I), predicted to result in the generation of a new stop codon due to a reading frameshift and the premature termination of translation. The other, derived from the father, represents a point mutation (G to A) in exon IX (mutation II), resulting in an amino acid substitution, Gly-376(GGC) to Asp(GAC), in the catalytic domain of the protein. Allele-specific oligonucleotide probe hybridization confirmed the presence of the two mutations. Mutation I would result in a truncated polypeptide of 169 amino acid residues that lacks the heavy chain. Mutation II gives rise to an alteration of a highly conserved amino acid, Gly-376. These data indicate that this patient is a compound heterozygote of the two mutant alleles, each one inherited from each parent. Transient expression assays using COS-7 cells transfected with mutated protein C expression vectors suggested that each of the two mutations leads to the protein C deficiency by causing an impairment of secretion of the respective mutant proteins.
P-selectin mediates Ca(2+)-dependent adhesion of activated platelets to many different types of leukocytes: detection by flow cytometry
Authors: de Bruijne-Admiraal LG , Modderman PW , Von dem Borne AE , Sonnenberg A 
Published: October 2019

Abstract
Previous studies have shown that thrombin-activated platelets interact through the P-selectin with neutrophils and monocytes. To identify other types of leukocytes capable of such an interaction, eosinophils, basophils, and lymphocytes were isolated from whole blood. Binding of these cells to activated platelets was examined in a double immunofluorescence assay and the results show that activated platelets not only bind to neutrophils and monocytes, but also to eosinophils, basophils, and subpopulations of T lymphocytes. Using monoclonal antibodies (MoAbs) specific for subsets of T cells, we could further demonstrate that the T cells which bind activated platelets are natural killer (NK) cells and an undefined subpopulation of CD4+ and CD8+ cells. All these interactions were dependent on divalent cations and were completely inhibited by an MoAb against P-selectin. Thus, P- selectin mediates the binding of activated platelets to many different types of leukocytes. Studies with leukocytes treated with proteases or neuraminidase have shown that the structures recognized by P-selectin are glycoproteins carrying sialic acid residues. Because the loss of binding of activated platelets to neuraminidase-treated neutrophils was almost complete, but only partial to treated eosinophils, basophils, and monocytes, the latter cell types may have different P-selectin ligands in addition to those present on neutrophils. We found that two previously identified ligands for P-selectin, the oligosaccharides Le(x) and sialyl-Le(x), had little or no inhibitory effect on adhesion of activated platelets to leukocytes and that binding was not inhibited by MoAbs against these oligosaccharides. In addition, there was no correlation between the expression of Le(x) on several cell types and their capacity to bind activated platelets. In contrast, the expression of sialyl-Le(x) on cells was almost perfectly correlated with their ability to bind activated platelets. Thus, while Le(x) cannot be a major ligand for P-selectin, a possible role for sialyl-Le(x) in P- selectin-mediated adhesion processes cannot be dismissed. Finally, activated platelets were found to bind normally to monocytes and neutrophils of patients with paroxysmal nocturnal hemoglobulinuria (PNH) and to neutrophils from which phosphatidyl inositol (PI)-linked proteins had been removed by glycosylphosphatidyl inositol-specific phospholipase C (GPI-PLC) digestion. This suggests that at least part of the P-selectin ligands on these cells are not GPI-anchored.
Presence of cross-reactive antibody between human immunodeficiency virus (HIV) and platelet glycoproteins in HIV-related immune thrombocytopenic purpura
Authors: Bettaieb A , Fromont P , Louache F , Oksenhendler E , Vainchenker W , Duedari N , Bierling P 
Published: October 2019

Abstract
We previously reported the presence in platelet eluates of autoantibodies directed against epitopes of the platelet glycoprotein (GP)IIb/IIIa complex in acquired immunodeficiency syndrome (AIDS)-free human immunodeficiency virus (HIV)-infected patients with immunologic thrombocytopenic purpura (ITP). We investigated whether HIV antibodies recognized platelet membrane antigens to determine whether the virus might be directly or indirectly responsible for the thrombocytopenia in this context. Direct eluates of platelets from 25 patients with HIV- related ITP contained IgG reacting with HIV-GP160/120 and also, in 45% of patients, detectable antiplatelet antibodies, immunochemically characterized as anti-GPIIb and/or anti-GPIIIa in 5 patients. Furthermore, serum HIV-GP160/120 antibodies could be absorbed on and eluted from platelets from normal non-HIV-infected healthy blood donors (indirect eluates). In contrast, GP160/120 antibodies present in the serum of nonthrombocytopenic HIV-infected patients were not absorbable on normal platelets in most patients, suggesting a pathogenic role in HIV-related ITP. We performed detailed studies of a patient with the highest titer of both HIV-GP160/120 and GPIIb/IIIa antibodies in direct and indirect platelet eluates. No antibody binding to GPIIb/IIIa- deficient Glanzmann thrombasthenic platelets was detected. Furthermore, binding/elution experiments conducted with insoluble recombinant GP160 (expressed in baculovirus) and purified platelet GPIIb/IIIa demonstrated that the patient's IgG bound specifically, through the F(ab')2 portion, to a common epitope of HIV-GP160/120 and platelet GPIIb/IIIa. This common epitope was present on a recombinant GP160 expressed in baculovirus but absent from another recombinant GP160 expressed in vaccinia virus, suggesting that the cross-reactivity is dependent on the glycosylation or conformational structure of the GP. We conclude that molecular mimicry between HIV-GP160/120 and platelet GPIIb/IIIa may explain at least some cases of ITP in AIDS-free HIV- infected patients.
Expression of selected human HOX-2 genes in B/T acute lymphoid leukemia and interleukin-2/interleukin-1 beta-stimulated natural killer lymphocytes
Authors: Petrini M , Quaranta MT , Testa U , Samoggia P , Tritarelli E , Care A , Cianetti L , Valtieri M , Barletta C , Peschle C 
Published: October 2019

Abstract
Although the key role of human homeobox (HOX) genes in development is well established, their function in adult cells is still under scrutiny. We have analyzed, in normal adult blood cell subpopulations, acute lymphoid leukemia (ALL) cells lines, and primary blasts, the RNA expression of all HOX-2 cluster genes (5′-2.5, 2.4, 2.3, 2.2, 2.1, 2.6, 2.7, 2.8, 2.9, 3′) and nine genes in the HOX-1, -3, and -4 cluster by Northern blotting, RNAse protection, and/or reverse transcriptase polymerase chain reaction (RT-PCR). The analyzed HOX-1, -3, and -4 genes were never expressed in all tested cell populations. Natural killer (NK) cells activated in interleukin-2 (IL-2)/IL-1 beta-treated cultures exhibit a gradually increasing, abundant expression of three HOX-2 genes (2.2, 2.6, 2.8), while three other genes (2.3, 2.1, 2.7) are expressed at a lower level at late culture times. However, no HOX-2 gene is expressed in quiescent lymphocytes (NK, B and T [T-cell receptor (TCR) alpha/beta, gamma/delta lymphocytes, thymocytes] cells), granulocytes, and monocytes. In B- and T-ALL cell lines, HOX-2 genes are expressed according to different patterns: (1) widespread transcription (seven of nine genes, including 2.3 and 2.6) in the Peer line bearing the TCR gamma/delta; (2) expression of 2.5, 2.2, and 2.6 in the SEZ 627 line, which derives from an HTLV-1+ T-helper leukemia; (3) transcription of 2.3 and 2.6 in both the T-ALL CEM line and four B- ALL lines (interestingly, CALLA- B-ALL lines are constantly 2.3/2.6 RNA+); (4) no HOX-2 gene expression was detected in one T- and two B- ALL lines. Primary blasts from five T- and five pre-B-ALL showed selective expression of one or more HOX-2 genes, namely 2.5, 2.2, 2.6, and 2.7. Our data are compatible with the hypothesis that selected HOX- 2 genes play a role in the IL-2/IL-1 beta-induced activation and/or proliferation of normal NK lymphocytes and possibly in the oncogenetic process of some T- and B-ALL.
Formation of a hyperdiploid karyotype in childhood acute lymphoblastic leukemia [see comments]
Authors: Onodera N , McCabe NR , Rubin CM 
Published: October 2019

Abstract
Hyperdiploidy with greater than or equal to 50 chromosomes is a frequent and distinct karyotypic pattern in the malignant cells of children with acute lymphoblastic leukemia. To understand better the mechanism of formation of the hyperdiploid karyotype, we studied 15 patients using 20 DNA probes that detect restriction fragment length polymorphisms. We first examined disomic chromosomes for loss of heterozygosity. Two patients had widespread loss of heterozygosity on all informative disomic chromosomes, and represent cases of near- haploid leukemia in which the chromosomes doubled. One other patient had loss of heterozygosity limited to chromosome 3; in this patient all of seven other informative disomic chromosomes retained heterozygosity. Loss of heterozygosity was not detected in the remaining 12 patients on a total of 87 informative disomic chromosomes. We then examined tetrasomic chromosomes for parental dosage. Of the 13 patients in whom widespread loss of heterozygosity was not present, 11 patients had tetrasomy 21; 10 of 11 (91%) had an equal dose of maternal and paternal alleles on chromosome 21 and only 1 of 11 (9%) had an unequal dose of parental alleles in a 3:1 ratio. These results suggest that the hyperdiploid karyotype usually arises by simultaneous gain of chromosomes from a diploid karyotype during a single abnormal cell division, and occasionally by doubling of chromosomes from a near- haploid karyotype. The hyperdiploidy in cases without widespread loss of heterozygosity is not caused by stepwise or sequential gains from a diploid karyotype or by losses from a tetraploid karyotype; the former should result in a 3:1 parental dosage for 67% of tetrasomic chromosomes (9% observed) and the latter should result in loss of heterozygosity for 33% of disomic chromosomes (1% observed). Additional studies of the molecular basis for this leukemia subtype are warranted.
A novel human lymphoma cell line (Deglis) with dual B/T phenotype and gene rearrangements and containing Epstein-Barr virus genomes
Authors: al Saati T , Delecluze HJ , Chittal S , Brousset P , Magaud JP , Dastugue N , Cohen- Knafo E , Laurent G , Rubin B , Delsol G 
Published: October 2019

Abstract
We report a new and apparently unique human lymphoma cell line termed Deglis. The line was established from a polymorphic centroblastic lymphoma. The cell line and its source carry a dual B-cell and T-cell phenotype and Epstein-Barr virus (EBV) genomes. Simultaneous expression of B-cell (CD19+, CD20+, CD23+, CD37+) and T-cell (CD2+, CD3+/-, CD7+, CD43+) antigens, activation antigens (CD30+, CDw70+) as well as CD68+, a macrophage-associated antigen, was observed on the cell line and its source. Genotypic studies of the cell line showed dual gene rearrangements. JH (on both primary tumor and the cell line) and C kappa were rearranged without expression of cytoplasmic or surface immunoglobulins. T-cell receptor-alpha (TCR-alpha) and TCR-beta genes were rearranged, but TCR-delta and TCR-gamma genes were in germline configuration. Apparently, functional transcripts of TCR-alpha and truncated transcripts for TCR-beta and TCR-delta were observed. EBV- encoded proteins (LMP and EBNA2) were expressed by the parent tumor and the cell line. Southern blot analysis showed the same clonal EBV genomes in the primary tumor and the cell line. Karyotypic analysis of the cell line showed several chromosomal abnormalities but normal chromosomal number. The characteristics of this cell line suggest that neoplastic transformation has occurred in a precursor cell broadly committed to lymphoid lineage. Further studies on this cell line may help resolve some issues in the physiopathology of lymphoid tumors.