bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polymorphic glycoprotein-1 on mouse platelets: possible role of Pgp-1 and LFA-1 in antibody-dependent platelet cytotoxicity involving complement
Authors: McCaffery PJ , Tan AS , Berridge MV 
Published: October 2019

Abstract
The presence of the Pgp-1 glycoprotein on mouse platelets is demonstrated by antibody-binding techniques, by immunoprecipitation, and by transblotting using the monoclonal antibody (MoAb) C71/26 against Pgp-1. C71/26 immunoprecipitates as a broad band of mol wt 87,000 to 100,000 as determined by radioiodination of the platelet cell surface and by the 3H-sodium borohydride labeling technique. Immunoblotting showed Pgp-1 expression on platelets to be quantitatively similar to its presence on macrophages and resolved platelet Pgp-1 into two bands of mol wt 87,000 and 97,000 whereas Pgp-1 on parasite-elicited peritoneal macrophages showed 82,000 and 87,000 mol wt species. Platelets and monocyte/macrophage cells from either peripheral blood or from the peritoneal cavity showed homogeneous binding of Pgp-1 antibody to greater than 97% of cells by flow cytometry. In contrast, lymphocytes from peripheral blood or from the spleen showed a heterogeneous binding pattern with 20% to 30% of cells being negative, and the majority weakly positive. In functional studies, MoAbs against CR1 and CR3 substantially inhibited platelet immune adherence, whereas C71/26 showed only marginal inhibitor. In contrast, C71/26 and other MoAbs against Pgp-1 inhibited platelet- dependent cytotoxicity of antibody-coated sheep erythrocytes in the presence of C5-deficient mouse plasma whereas M1/70 against CR3 showed no effect. In this assay, MoAbs against the alpha- and beta-subunits of leukocyte functional molecule LFA-1 also inhibited platelet cytotoxicity. These results show that the platelet cell surface moieties Pgp-1 and LFA-1 are involved in or closely associated with antibody-dependent cellular cytotoxicity by platelets.
Flow cytometric analysis of human bone marrow: I. Normal erythroid development
Authors: Loken MR , Shah VO , Dattilio KL , Civin CI 
Published: October 2019

Abstract
Flow cytometry was used to identify maturational differences of erythroid lineage cells in normal human bone marrow by combining physical characteristics, the expression of multiple cell surface antigens, and nucleic acid content. Normal low-density bone marrow cells could be divided into four populations, based on forward and right-angle light scattering. Erythroid cells, at different maturational stages, were found in three of these four marrow subpopulations. The sequentially correlated expression of three cell surface markers--HLe-1, transferrin receptor, and glycophorin--allowed us to study erythroid maturation from the colony forming cell to the mature erythrocyte. HLe-1 was expressed on the earliest identifiable erythroid cells and was progressively lost as the cells matured. Transferrin receptor began to be expressed at the BFU-E stage and disappeared at the late reticulocyte stage. Transferrin receptor expression preceded glycophorin expression, the latter beginning on morphologically recognizable erythroid precursors just after the CFU-E stage. In contrast to both HLe-1 and transferrin receptor, which were progressively lost during the maturational process, once glycophorin had been maximally expressed on the cell surface, it remained at constant quantities to the mature erythrocyte stage. Although developing nucleated erythroid cells at approximately the normoblast stage had light-scattering properties similar to those of lymphoid cells, these two cell types could be resolved by cell surface antigen expression. Normoblasts were glycophorin positive and HLe negative, whereas lymphoid cells expressed HLe and either Leu 4, Leu 11, or Leu 12. Decreases in cellular nucleic acid content, corresponding first to the extrusion of the nucleus and second to the loss of reticulum, characterized the later stages of erythroid development. These characteristics and instrumentation can be used to purify erythroid cells at various developmental stages.
Amantadine potentiates T lymphocyte killing by an anti-pan-T cell (CD5) ricin A-chain immunotoxin
Authors: Siena S , Villa S , Bregni M , Bonnadonna G , Gianni AM 
Published: October 2019

Abstract
The studies described in this report demonstrate that 1-adamantanamine hydrochloride (amantadine) is a potent enhancer of the cytotoxic activity of the anti-pan-T lymphocyte (CD5) T101 monoclonal antibody conjugated to purified ricin A-chain (T101-immunotoxin; T101-IT). We also demonstrate that T101-IT in the presence of amantadine does not induce immunotoxin-mediated cytotoxicity in nontarget cells such as human marrow hematopoietic progenitor cells. These results provide further knowledge for the improvement of ex vivo purification of human bone marrow from normal or leukemic T cells prior to allogeneic or autologous stem cell transplantation, respectively. Furthermore, since amantadine has long been employed safely in human therapy, its use in conjunction with immunotoxins might be exploited in vivo.
Possible absence of common polymorphisms in coagulation factor IX gene in Japanese subjects
Authors: Kojima T , Tanimoto M , Kamiya T , Obata Y , Takahashi T , Ohno R , Kurachi K , Saito H 
Published: October 2019

Abstract
Four distinct intragenic polymorphisms in the coagulation factor IX gene which have been reported to be important for family diagnosis of Caucasian hemophilia B were studied in 51 normal Japanese subjects (21 males and 30 females). High-molecular-weight DNA prepared from peripheral blood lymphocytes were digested with endonuclease, Ddel, Mspl, Taql or Xmnl, and were studied by Southern blot analysis with factor IX complementary DNA as a probe. None of the minor fragments produced by these enzymes was found in the normal Japanese DNA samples tested, although the probe detects minor allelic forms in control Caucasian DNA samples. Our data suggest that the frequent polymorphic sites found in Caucasians are possibly absent in the Japanese population.
New abnormalities in the morphology, cell surface receptors, and electrolyte metabolism of In(Lu) erythrocytes
Authors: Udden MM , Umeda M , Hirano Y , Marcus DM 
Published: October 2019

Abstract
The In(Lu) phenotype is inherited as an autosomal dominant trait and is characterized by suppression of the Lutheran, P1, i, and Aua erythrocyte blood group antigens. We have developed a monoclonal antibody (L21) that strongly agglutinates all erythrocytes except In(Lu), and we have identified eight In(Lu) individuals among 42,000 blood donors tested. Studies of two families confirmed the dominant mode of inheritance and revealed several new features of this phenotype. The erythrocytes of all five affected individuals from the two families exhibited diminished hemagglutination by the lectin concanavalin A, although they reacted normally with several other lectins. The erythrocytes of two affected individuals in one family exhibited marked acanthocytosis. The erythrocytes of the proposita of the other family exhibited a mild degree of poikilocytosis, but the cells of the other two affected individuals in this family had normal morphology. The osmotic fragility of fresh In(Lu) erythrocytes was normal, but after incubation for 24 hours at 37 degrees C in plasma the In(Lu) cells exhibited a marked increase in resistance to osmotic lysis. During the incubation period the erythrocytes lost K+ and their total cation content was diminished. These data indicate that in addition to the suppression of blood group antigens noted previously, the In(Lu) phenotype includes a variety of morphological abnormalities and a defect in electrolyte metabolism. The use of L21 and similar monoclonal antibodies provides a more sensitive means of detecting In(Lu) erythrocytes than typing with human anti-Lub antisera.
Evidence favoring lineage fidelity in acute nonlymphocytic leukemia: absence of immunoglobulin gene rearrangements in FAB types M4 and M5
Authors: Ackland SP , Westbrook CA , Diaz MO , Le Beau MM , Rowley JD 
Published: October 2019

Abstract
The concept of lineage fidelity in acute leukemia has recently been challenged by the finding of rearrangements of the immunoglobulin heavy chain genes in a leukemic cell line and in a small number of sporadic cases of acute nonlymphocytic leukemia with a monocytic phenotype. We therefore screened leukemic blood or bone marrow samples of 33 adult patients with acute nonlymphocytic leukemia of FAB types M4 (23 patients) and M5 (10 patients); 28 were obtained at diagnosis and 5 at relapse. All cases were well characterized pathologically and histochemically. Cytogenetic analysis performed in each case demonstrated karyotypes that were representative of those generally seen in these types of leukemia, with a clonal abnormality present in all except 9 of 32 patients who were successfully studied. DNA prepared from each sample was digested with the restriction enzyme BamH1 and analyzed by Southern blot hybridization to probes for the JH region of the immunoglobulin heavy chain. All 33 cases had DNA retained in the germline configuration with no evidence of rearrangement. This finding supports the concept of lineage fidelity, and suggests that true interlineage infidelity, myeloid to lymphoid, is a rare occurrence in adult acute nonlymphocytic leukemia.
Successful graft-versus-host disease prevention without graft failure in 32 HLA-identical allogeneic bone marrow transplantations with marrow depleted of T cells by monoclonal antibodies and complement
Authors: Herve P , Cahn JY , Flesch M , Plouvier E , Racadot E , Noir A , Couteret Y , Goldstein G , Bernard A , Lenys R 
Published: October 2019

Abstract
Thirty-two patients with acute leukemia, chronic granulocytic leukemia, or multiple myeloma received a T lymphocyte-depleted HLA-identical marrow. After being treated with pan-T monoclonal antibodies (MoAbs) and one round of baby rabbit complement, the mean percentage of T cell depletion was 94% +/- 4%. The number of residual viable T cell infused to the patient was 0.99 +/- 0.65 X 10(6) per kg body weight. The patients were conditioned with fractionated total body irradiation (TBI) (12 Gy) preceding high doses of cyclophosphamide (120 mg/kg). Methotrexate was used as an additional immunosuppressant in the first ten patients. For the following 22 patients no posttransplant immunoprophylaxis was administered. Eight patients died within three months due to complications related to transplantation. Engraftment was achieved in all evaluable patients, and no patient has a late graft failure. The proof of total chimerism was established in 24 patients. Twenty-four of 27 evaluable patients (88%) did not have an acute graft- v-host disease (GVHD) greater than grade 0 to 1. Two patients had a grade 2 (skin only), and one patient had a grade 4 acute GVHD (the latter had only 80% of T cell depletion). A medullary relapse occurred in 11 patients (nine of them had previously been defined as “high risk leukemia”). Our data suggest that it may not be necessary to deplete nearly all T cells to prevent acute GVHD in recipients of HLA-identical marrow.
Fibrinolysis in pregnancy: a study of plasminogen activator inhibitors
Authors: Kruithof EK , Tran-Thang C , Gudinchet A , Hauert J , Nicoloso G , Genton C , Welti H , Bachmann F 
Published: October 2019

Abstract
During pregnancy the plasma concentration of two different inhibitors of plasminogen activators (PAIs) increases. The only one found in the plasma of nonpregnant women (PAI1) is immunologically related to a PAI of endothelial cells; its plasma activity, as deduced from the inhibition of single-chain tissue-type plasminogen activator (t-PA), increased from 3.4 +/- 2.3 U/mL (mean +/- 95% confidence limits) in the plasma of nonpregnant women to 29 +/- 7 U/mL at term, and its antigen level, measured by a radioimmunoassay, increased from 54 +/- 17 ng/mL to 144 +/- 25 ng/mL. In pregnancy plasma a second PAI (PAI 2) related to a PAI found in placenta extracts was observed. Its level, quantified with a radioimmunoassay, increased from below the detection limit (approximately 10 ng/mL) in normal plasma to 260 ng/mL at term. One hour after delivery, PAI 1 activities and antigen decreased sharply, but the PAI 2 antigen levels remained constant. Three days later, the PAI 1 antigen levels had fallen to normal levels, but the PAI 2 antigen levels were still at least eightfold above the nonpregnant values. During pregnancy, the t-PA and prourokinase (u-PA) antigen concentrations increased 50% and 200%, respectively, whereas the plasminogen and alpha 2-antiplasmin levels remained constant. Despite the large variations in the levels of PAs and PAIs, the overall fibrinolytic activity as measured in diluted plasma by a radioiodinated fibrin plate assay did not change significantly. Just after delivery, a great increase in the t-PA antigen levels was observed. Three to five days after delivery most parameters of the fibrinolytic system were normal again. Our results demonstrate that during pregnancy and in the puerperium profound alterations of the fibrinolytic system occur that are characterized by increases in PAs and their inhibitors, but these alterations do not affect the overall fibrinolytic activity.
A new variant of the alpha subunit of spectrin in hereditary elliptocytosis
Authors: Lambert S , Zail S 
Published: October 2019

Abstract
A kindred is described in which two brothers with a poikilocytic variant of hereditary elliptocytosis (HE) were found to have a defect of spectrin dimer association and a decreased spectrin-band 3 ratio. Two-dimensional gel electrophoresis of limited tryptic digests of their spectrin revealed decreased amounts of the alpha I domain when compared with control digests and the appearance of two major peptides with mol wts of 43,000 and 42,000 and isoelectric points (5.75 to 5.85) more basic than the alpha I domain. Tryptic digests of spectrin from the asymptomatic mother of the two brothers were normal. Immunoblots of the two-dimensional gels using an antiserum to the alpha I domain revealed that the 43,000- and 42,000-dalton peptides were derived from the alpha I domain, along with a series of lower mol wt peptides, some of which were below the detection limits of Coomassie blue-stained gels. Limit chymotryptic maps of 125I-labeled tryptic peptides confirmed that the 43,000- and 42,000-dalton peptides were derived from the alpha I domain. This kindred represents a new structural variant of spectrin in HE in that the major abnormal tryptic peptides derived from the alpha I domain have lower mol wts and more basic isoelectric points than hitherto described.
Relationship of the hematopoietic cycle to the combined activities of a stimulator and a short-lived inhibitor
Authors: Burke PJ , Karp JE 
Published: October 2019

Abstract
Substances that circulate in the blood following drug-induced bone marrow aplasia produce a biphasic curve of DNA synthesis in cells in liquid and semisolid cultures which reflect relative concentrations of these growth regulators of hematopoiesis. This net effect magnified by induced marrow failure in human, rat, and mouse is a sinusoidal curve that is the reciprocal of the WBC. Generated in the bone marrow, humoral stimulating activity (HSA) produces peak growth of colonies in agar (CFU-GM) during the proliferative phase of bone marrow recovery, whereas humoral inhibitory activity (HIA), present at the time of marrow maturation, suppresses colony growth. Split femurs from rats given cyclophosphamide (CY) and killed at regular intervals condition media that affect DNA synthesis in a fashion similar to that of HSA-HIA in the rats' sera. In Dexter cultures, HSA is derived from the adherent rather than the hematopoietic cell, whereas HIA is produced by that nonadherent cell. Animals treated with a lethal dose of busulfan (BU) produce large amounts of HSA in vivo until death. Those transplanted with adherent bone marrow cells depleted of hematopoietic cells on day 1 after BU also die, whereas those given nonadherent marrow cells survive and generate HIA at the time of bone marrow recovery. HSA and media conditioned by bone marrow stromal cells causes an increase in spleen colonies (CFU-S), as does HIA. These studies support the contention that the net effect of putative regulators of hematopoiesis, measured in the drug-perturbed state, consist of a constantly present stimulator emanating from bone marrow stroma, and a variable inhibitor produced by maturing hematopoietic bone marrow cells.
Spectrin is associated with membrane-bound actin filaments in platelets and is hydrolyzed by the Ca2+-dependent protease during platelet activation
Authors: Fox JE , Reynolds CC , Morrow JS , Phillips DR 
Published: October 2019

Abstract
We recently showed that platelets contain submembranous actin filaments that are linked to glycoprotein (GP) Ib on the plasma membrane. In the present study, experiments were performed to determine whether spectrin was associated with these filaments. The membrane-bound filaments were isolated from Triton X-100 (Sigma, St Louis) lysates of unstimulated platelets by differential centrifugation. Platelet spectrin was detected immunologically by using antibodies against human brain and RBC spectrin. Immunoblots showed that platelet spectrin consisted of two polypeptides (mol wt 240,000 and 235,000) that were similar in apparent mol wt to those of the alpha and beta chains of brain spectrin but differed slightly from those of RBC spectrin (mol wt 240,000 and 220,000). Immunoprecipitation experiments identified platelet spectrin as two minor polypeptides migrating on sodium dodecyl sulfate (SDS)- polyacrylamide gels between actin-binding protein (mol wt 250,000) and the platelet polypeptide P235 (mol wt 235,000). Immunoblots of fractions isolated from Triton X-100-lysed platelets revealed that the alpha and beta chains of platelet spectrin were associated almost entirely with the actin filaments that were linked to the plasma membrane. Little spectrin was recovered in the Triton X-100-soluble fraction or with the actin filaments that were not membrane bound. During activation of platelets with thrombin or ionophore A23187, the alpha and beta chains of spectrin were hydrolyzed, generating a major degradation product of mol wt 160,000 and a minor one of mol wt 170,000. These two hydrolytic products were also generated in Triton X- 100 lysates incubated in the presence of Ca2+ but were not produced when lysates were treated with leupeptin, ethylene glycol bis(beta- aminoethyl ether)-N,N,N′,N′-tetraacetic acid (EGTA), or N- ethylmaleimide, known inhibitors of the Ca2+-dependent protease. These experiments show that spectrin is a previously unidentified component of the membrane-bound actin filament network and that hydrolysis of spectrin by the Ca2+-dependent protease may regulate the interactions of the filaments during platelet activation.
Purification and partial amino acid sequence of human platelet membrane glycoproteins IIb and IIIa
Authors: Hiraiwa A , Matsukage A , Shiku H , Takahashi T , Naito K , Yamada K 
Published: October 2019

Abstract
The glycoprotein (GP) IIb-IIIa complex was isolated from human platelet membranes by immunoaffinity chromatography using a monoclonal antibody specific for GP IIb-IIIa. GP IIb and IIIa were further separated in the presence of sodium dodecyl sulfate (SDS) by gel filtration high- performance liquid chromatography (HPLC). Two cycles of this procedure yielded almost complete separation of homogeneous preparations of GP IIb and IIIa. Each protein was then digested with lysyl endopeptidase (Achromobacter protease I), which cleaves at the carboxyl side of lysine residues, and the resulting oligopeptides from GP IIb and IIIa were fractionated with HPLC using a C18 reverse-phase column. Comparison of the elution profiles showed no obvious homology between the two proteins. Amino acid sequences of selected oligopeptides from each glycoprotein were determined using a gas-phase protein sequencer. Sixty amino acid residues (26 residues for IIb and 34 residues for IIIa) were identified.
Prothrombin Tokushima: characterization of dysfunctional thrombin derived from a variant of human prothrombin
Authors: Inomoto T , Shirakami A , Kawauchi S , Shigekiyo T , Saito S , Miyoshi K , Morita T , Iwanaga S 
Published: October 2019

Abstract
A mutant prothrombin, designated prothrombin Tokushima, was purified from plasma of a proband with 12% of normal plasma clotting activity and 42% of normal prothrombin antigen. The purified preparation gave a single band with the same mobility as that of “prothrombin” by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The factor Xa-catalyzed proteolysis of prothrombin Tokushima examined by SDS-PAGE was found to be identical to that of “prothrombin.” Subsequently thrombin Tokushima was prepared by CM-Sepharose CL-6B column chromatography after prothrombin activation by factor Xa. The molecular weight of thrombin Tokushima estimated by SDS-PAGE was identical to that of “thrombin.” Thrombin Tokushima exhibited less than 22% of normal clotting activity, and the value of kcat/Km (mumol/L-1 second-1) was less than one tenth of that of “thrombin” when Boc-Val- Pro-Arg-4-methylcoumaryl-7-amide was used as a substrate. However, active site titration using p-nitrophenyl-p′-guanidinobenzoate failed to detect any difference between the two. Thrombin Tokushima was 2.5% as effective as “thrombin” in inducing platelet aggregation. Interaction of thrombin Tokushima with antithrombin III was much slower than “thrombin” when followed by SDS-PAGE. Based on the residual thrombin activity, it was 33% as effective as “thrombin” in forming a complex with antithrombin III. These results indicate that the molecular defect resides in the thrombin portion of prothrombin Tokushima and that the binding sites for various substrates appear to be greatly impaired.
Human erythroleukemia cells adhere to fibronectin: evidence for a Mr 190,000-receptor protein
Authors: Virtanen I , Ylanne J , Vartio T 
Published: October 2019

Abstract
Human erythroleukemia cells (K562) adhered rapidly on fibronectin (Fn)- coated growth substratum under serum-free conditions. The adhesion could be quantitatively inhibited by the synthetic peptide Arg-Gly-Asp- Ser (RGDS) and upon hemin-induced differentiation or trypsinization of the cells. Many of the cells also displayed rapid spreading that led to a redistribution of F-actin into spreading edges and in many cells also to a formation of typical actin fibers attaching to the ventral aspect of the cells. The spreading of the cells was inhibited by cytochalasin B but not by microtubule-disrupting drugs, suggesting an active role for the microfilament system in the spreading process. Direct overlay assay of electrophoretically separated polypeptides with 125I-Fn showed that in K562 cells there is a major Mr 190,000 Fn-binding protein that is lost upon differentiation. A similar overlay assay with purified plasma and cellular Fns followed by immunostaining with anti-Fn antibodies revealed a reaction with a similar polypeptide. The binding of Fns on the nitrocellulose sheets could be inhibited and the bound Fn eluted by using the RGDS peptide. From octylglucoside extracts of radioactively surface-labeled cells, distinct Mr 190,000/185,000 membrane glycoproteins bound to Fn-heptapeptide-Sepharose, further suggesting that the Mr 190,000 polypeptide would be the Fn-receptor of the K562 cells.