bluuebunny/crossref_metadata_2025 huggingface dataset:
Thrombin-induced increase in surface expression of epitopes on platelet membrane glycoprotein IIb/IIIa complex and GMP-140 is a function of platelet age
Authors: Savage B , Hunter CS , Harker LA , Woods VL Jr , Hanson SR
Published: October 2019

Platelets are heterogeneous in the content of membrane glycoprotein (GP)IIb/IIIa complex. To determine whether this heterogeneity is related to changes associated with platelet aging in the circulation, newly released platelets, obtained during recovery from nonimmune- mediated acute experimental thrombocytopenia in baboons, were studied. Monoclonal antibody (MoAb) binding to epitopes expressed on GPIIb/IIIa complex (LJ-CP8), GMP-140 (S12), and GPIa/IIa (12F1) was measured on control platelets (comprising platelets with a normal age distribution; mean age 60 to 72 hours) and newly formed platelets (mean age 12 hours), both in the resting state and after thrombin stimulation. Whereas LJ-CP8 binding to resting control platelets increased by 34% upon stimulation by gamma-thrombin from 30,885 +/- 1,171 to 41,458 +/- 1,311 molecules/platelet at saturating concentrations of antibody, LJ- CP8 binding to resting young platelets did not increase significantly upon thrombin stimulation (31,878 +/- 3,330 and 33,791 +/- 3,486 molecules/platelet, respectively). Similarly, binding of antibody S12 in response to maximal thrombin stimulation was reduced by 42% from 10,246 +/- 834 molecules/platelet at saturating concentrations of S12 for control platelets to 5,971 +/- 665 molecules/platelet for young platelets (P = .001). S12 binding to unstimulated platelets was less than 10% of the binding observed after thrombin stimulation at all concentrations of S12 for both control and young platelets. However, maximal binding of antibody 12F1 to resting control platelets did not differ significantly from that observed with resting young platelets (2,926 +/- 167 and 2,857 +/- 208 molecules/platelet, respectively), and 12F1 binding was unchanged after thrombin stimulation for both control and young platelets. We conclude that the thrombin-induced increase in the expression of epitopes on platelet membrane GPIIb/IIIa complex and GMP-140 is a function of platelet age.
Elevated serum-soluble interleukin-2 receptor (Tac antigen) levels in chronic myelogenous leukemia patients with blastic crisis
Authors: Motoi T , Uchiyama T , Hori T , Itoh K , Uchino H , Ueda R
Published: October 2019

We examined the expression of cell-surface interleukin-2 (IL-2) receptor (Tac antigen) on peripheral blood leukemic cells and measured soluble IL-2 receptor p55(alpha) chain (sIL-2R) levels in sera from chronic myelogenous leukemia (CML) patients with blastic crisis. Flow cytofluorometric analysis performed by dual immunofluorescence in three cases demonstrated coexpression of Tac antigen with myeloid (CD13, CD14, or CD33) or lymphoid (CD10) antigen on significant proportions of peripheral blood leukemic cells. Radiolabeled IL-2-binding assay demonstrated the specific IL-2 binding sites in three cases examined. The exogenous IL-2, however, failed to induce proliferative response. A myeloid cell line, Yut-K3, established from peripheral blood leukemic cells from a CML patient with blastic crisis, also expressed cell- surface Tac antigen and CD13 concurrently. SIL-2R assay showed that Yut- K3 released a detectable amount of sIL-2R in its culture supernatant. The serum sIL-2R levels were significantly elevated (range: 2,580 to 172,000 U/mL) in 12 CML patients with blastic crisis and were slightly elevated in ten patients in chronic phase (range: 250 to 820 U/mL) and in three in accelerated phase (range: 790 to 1,305 U/mL) compared with those in 24 normal controls (range: 70 to 695 U/mL, P less than .01). These results indicated that the leukemic cells from CML patients with blastic crisis expressed and released IL-2 receptor (Tac antigen). Longitudinal studies performed in three cases of CML with blastic crisis showed that the change of serum sIL-2R level was closely associated with that of the number of peripheral blood leukocytes and blasts, the percentage of blasts and serum LDH levels, also suggesting that the serum sIL-2R level is a useful clinical indicator of the leukemic cell burden in vivo.
Platelet transfusion therapy for alloimmunized patients: selective mismatching for HLA B12, an antigen with variable expression on platelets
Authors: Schiffer CA , O'Connell B , Lee EJ
Published: October 2019

There can be wide variation in the expression of the HLA B12 antigen and its “splits,” B44 and 45, on the platelets and lymphocytes from the same individual. One hundred sixty-two single donor platelet transfusions mismatched only for this antigen group were administered to 54 alloimmunized patients who were refractory to random donor platelets. Satisfactory increments (one-hour post-transfusion corrected- count increment [CCI] greater than 7,500) were seen following 111/162 transfusions (69%). In 31 patients (57%), all transfusions (n = 85) produced CCI greater than 7,500, and 76% of patients received some transfusions that were satisfactory. Of note is that ten patients had excellent increments despite either preformed lymphocytotoxic antibody against the mismatched antigen or positive lymphocytotoxic cross- matches with the donor. In contrast, poor increments were seen in ten recipients under similar circumstances, implying disparities in antigen expression on the platelets and lymphocytes of different donors. There was no obvious pattern of other donor HLA antigens which could be correlated with these differences. The HLA B12 antigen group is relatively common (found in approximately 25% of the population), and these data indicate that selective mismatching for these antigens can be an effective donor-selection strategy to increase the number of donors for alloimmunized recipients.
Isolation in a single step of a highly enriched murine hematopoietic stem cell population with competitive long-term repopulating ability
Authors: Szilvassy SJ , Lansdorp PM , Humphries RK , Eaves AC , Eaves CJ
Published: October 2019

A simple procedure is described for the quantitation and enrichment of murine hematopoietic cells with the capacity for long-term repopulation of lymphoid and myeloid tissues in lethally irradiated mice. To ensure detection of the most primitive marrow cells with this potential, we used a competitive assay in which female recipients were injected with male “test” cells and 1 to 2 x 10(5) “compromised” female marrow cells with normal short-term repopulating ability, but whose long-term repopulating ability had been reduced by serial transplantation. Primitive hematopoietic cells were purified by flow cytometry and sorting based on their forward and orthogonal light-scattering properties, and Thy-1 and H-2K antigen expression. Enrichment profiles for normal marrow, and marrow of mice injected with 5-fluorouracil (5- FU) four days previously, were established for each of these parameters using an in vitro assay for high proliferative potential, pluripotent colony-forming cells. When all four parameters were gated simultaneously, these clonogenic cells were enriched 100-fold. Both day 9 and day 12 CFU-S were copurified; however, the purity (23%) and enrichment (75-fold) of day 12 CFU-S in the sorted population was greater with 5-FU-treated cells. Five hundred of the sorted 5-FU marrow cells consistently repopulated recipient lymphoid and myeloid tissues (greater than 50% male, 1 to 3 months post-transplant) when co-injected with 1 to 2 x 10(5) compromised female marrow cells, and approximately 100 were sufficient to achieve the same result in 50% of recipients under the same conditions. This relatively simple purification and assay strategy should facilitate further analysis of the heterogeneity and regulation of stem cells that maintain hematopoiesis in vivo.
Differences between binding of one-chain and two-chain tissue plasminogen activators to non-cross-linked and cross-linked fibrin clots
Authors: Husain SS , Hasan AA , Budzynski AZ
Published: October 2019

Interaction of tissue plasminogen activator (t-PA) with fibrin plays a key role in regulation of plasminogen activation and clot dissolution. Previous investigations of t-PA-fibrin interaction, using incorporation of t-PA into polymerizing fibrin clots, have suggested that no significant differences exist in the binding of one-chain or two-chain t-PA to non-cross-linked or cross-linked fibrin. In the present study, binding of 125I-labeled and affinity-purified one-chain and two-chain forms of t-PA to preformed non-cross-linked or cross-linked, sonicated suspension of fibrin was investigated. Interaction of one-chain t-PA with cross-linked fibrin involved a single type of binding site with dissociation constant (kd) of 0.58 mumol/L and a stoichiometry (n) of 1.5. Interaction of one-chain t-PA with non-cross-linked fibrin, however, involved two classes of binding sites with dissociation constants of 0.32 and 1.5 mumol/L and corresponding number of binding sites equal to 0.57 and 2.0, respectively. In contrast to the binding of one-chain t-PA to cross-linked fibrin by a limited number of sites, two-chain t-PA appeared to involve a considerably greater number of sites (minimum six) whose dissociation constant was 3.2 mumol/L. Interaction of two-chain t-PA with non-cross-linked fibrin also showed the presence of many binding sites (minimum seven) with approximate dissociation constant of 6.4 mumol/L, as well as a few (n = 0.012) high- affinity sites with a kd of 0.011 mumol/L epsilon-Aminocaproic acid did not completely reverse the binding of either one-chain t-PA or two- chain t-PA to fibrin. The present findings suggest that the fibrin- binding properties of t-PA undergo considerable changes on proteolytic conversion from one-chain to two-chain t-PA, catalyzed under physiologic conditions by plasmin. The cleavage of one-chain t-PA to two-chain t-PA allows to bind to a large number of low-affinity binding sites on fibrin. Cross-linking of fibrin by factor XIIIa results in masking of high-affinity binding sites that are present in non-cross- linked fibrin. We propose that both plasmin and factor XIIIa play an important regulatory role in dissolution of blood clots by modulating t- PA-fibrin interaction.
Dengue virus, a flavivirus, propagates in human bone marrow progenitors and hematopoietic cell lines [see comments]
Authors: Nakao S , Lai CJ , Young NS
Published: October 2019

Dengue and other arbovirus diseases are frequently associated with bone marrow failure. We show that dengue type 4 (DEN4) propagates in colonies derived from immature human bone marrow progenitors. DEN4 was propagated in BFU-E-derived colonies and replication was dependent on erythropoietin. DEN4 was not cytotoxic. In inoculated cultures, diffuse bursts with many clusters contained large amounts of DEN4 RNA. In contrast to dengue infection of macrophages, virus propagation in semisolid culture was sustained and not enhanced by subneutralizing amounts of antibody. DEN4 also was efficiently propagated in human hematopoietic cell lines, especially those with erythroid properties. In K562 cells, DEN4 infection persisted for months; greatly slowed cell growth, again without cytotoxicity; and resulted in cytopathic changes in cell appearance. Flaviviruses can infect human hematopoietic cells and alter their proliferative capacity.
In vivo induction of gamma interferon and tumor necrosis factor by interleukin-2 infusion following intensive chemotherapy or autologous marrow transplantation
Authors: Heslop HE , Gottlieb DJ , Bianchi AC , Meager A , Prentice HG , Mehta AB , Hoffbrand AV , Brenner MK
Published: October 2019

Interleukin-2 (IL-2) therapy may improve immune reconstitution and reduce the risk of leukemic relapse in the setting of minimal residual disease by augmenting cytotoxic effector mechanisms directed at residual malignant cells. In addition, IL-2 in vitro promotes the release of cytokines including gamma-interferon (gamma-IFN) and tumor necrosis factor (TNF), which also possess antileukemic activity and can enhance granulocyte function. To determine if IL-2 infusion induces release of gamma-IFN and TNF in vivo in sufficient quantity to mediate these effects, we have measured serum levels of these cytokines and secretion by lymphocytes obtained from patients receiving this cytokine in a phase 1 trial. Serum gamma-IFN was undetectable pre-IL-2 and increased to 1.5 to 17 U/mL during IL-2 infusion (P less than .05). Culture of patient lymphocytes for 48 hours produced 1.2 U gamma-IFN/2 x 10(6) cells/mL pre-IL-2 rising to 50 U/2 x 10(6) cells/mL when the lymphocytes were obtained during therapy (P less than .05). Lymphocyte subset analysis showed that both CD3+ and CD16+ cells secreted gamma- IFN in response to IL-2. TNF secretion by lymphocytes also rose during IL-2 infusion from a mean of 5 U/mL to 14.4 U/mL (P less than .01) although no rise was seen in serum levels. The material secreted by IL- 2-stimulated lymphocytes is bioactive as addition of supernatants from lymphocytes obtained during IL-2 therapy to cultures of myeloid blasts significantly inhibited clonogenic growth. IL-2-induced secretion of these cytokines mediated this inhibition as it could be partially blocked by either anti-gamma-IFN or anti-TNF antibodies. Preincubation of granulocytes with the same supernatants produced enhanced oxidative metabolism, measured by chemiluminescence in response to N-formyl- methionyl-leucyl-phenylalanine (FMLP). This effect also could be partially abrogated by anti-gamma-IFN and anti-TNF antibodies. Therefore, secondary cytokine secretion may boost granulocyte function and contribute to the antileukemic effects of IL-2 infusion in patients following bone marrow transplantation or chemotherapy.
Peripheral lymph node helper T-cell recovery after syngeneic bone marrow transplantation in mice prepared with either gamma-irradiation or busulfan
Authors: Samlowski WE , Araneo BA , Butler MO , Fung MC , Johnson HM
Published: October 2019

The optimum marrow ablative regimen for preparing recipients of bone marrow transplantation (BMT) has not been established. gamma- Irradiation, but not busulfan, produces a characteristic microvascular injury pattern which results in depressed capacity of normal lymphocytes to localize into the lymph nodes of syngeneic murine BMT recipients. Since peripheral lymph nodes are important sites for initiation and amplification of immune responses, the preparative regimen might delay recovery of regionally compartmentalized immune functions after BMT. We evaluated the effects of busulfan and gamma- irradiation on the phenotypic and functional reconstitution of helper T- cell function within the peripheral lymph nodes of BMT recipients. Both marrow ablative regimens caused a protracted delay in regeneration of peripheral lymph node CD4+ T cells. Specific helper T-cell functions, such as contact hypersensitivity and alloantigen responses, remained significantly depressed in the lymph nodes of irradiated mice for prolonged periods (up to 60 weeks). These responses recovered more rapidly in busulfan-treated BMT recipients. In contrast, the capacity of peripheral lymph node T cells to provide “help” for antigen-specific immunoglobulin production was only transiently depressed by either preparative regimen. Our experiments confirm the hypothesis that the marrow ablative regimen, particularly gamma-irradiation, may contribute to the period of immunodeficiency which follows BMT. The pattern of immune recovery observed suggests that preparative total body irradiation (TBI) may selectively depress the regional recovery of the TH1 [interleukin-2 (IL-2) and gamma-interferon (gamma-IFN) secreting] lymphocyte subset.
Suppressive effect of Sl/Sld mouse embryo-derived fibroblast cell lines on diffusible factor-dependent proliferation of mast cells
Authors: Onoue H , Ebi Y , Nakayama H , Ru XM , Kitamura Y , Fujita J
Published: October 2019

Two modes of mast cell growth are present, one dependent on diffusible growth factors (interleukins [IL] 3 and 4) and another dependent on contact with fibroblasts. The 3T3 fibroblast cell lines derived from WCB6F1-+/+ mouse embryos supported the proliferation of cultured mast cells (CMC), whereas the 3T3 fibroblast cell lines from WCB6F1-Sl/Sld mouse embryos did not. To investigate the relationship between growth factor-dependent and fibroblast-dependent growths of mast cells, we cocultured CMC and 3T3 fibroblasts in the presence of diffusible growth factors. WCB6F1-+/+ mouse embryo-derived 3T3 cells did not affect the growth factor-dependent proliferation of CMC, but WCB6F1-Sl/Sld mouse embryo-derived 3T3 cells significantly suppressed the proliferation. Close cell-to-cell contact was necessary for the suppression. The NWS1 fibroblast cell line was established from the spleen cells of an adult WBB6F1-+/+ mouse. Although the NWS1 cell line had no supporting effect on the proliferation of CMC in the absence of diffusible growth factors, it did not suppress the proliferation of CMC induced by the growth factors. The present result suggests that a product of mutant Sl genes may be involved in the suppressive activity of WCB6F1-Sl/Sld mouse embryo-derived 3T3 cells.
Bryostatin 1 induces differentiation of B-chronic lymphocytic leukemia cells
Authors: Drexler HG , Gignac SM , Jones RA , Scott CS , Pettit GR , Hoffbrand AV
Published: October 2019

Peripheral blood cells from nine patients with B-chronic lymphocytic leukemia (B-CLL) were treated in vitro with bryostatin 1 (a macrocyclic lactone derived from a marine invertebrate). Like the phorbol ester 12- 0-tetradecanoyl-phorbol 13-acetate (TPA), bryostatin 1 activates protein kinase C (PKC), which plays a central role in the phosphatidylinositol signal transduction pathway. The effects of bryostatin 1 alone and in combination with TPA or with the calcium mobilizing ionophore A23187 were assessed by morphological appearance, cell adherence and aggregation, RNA and DNA synthesis, and immunoglobulin (Ig) production. While eight of nine B-CLL cultures remained proliferatively inert, bryostatin 1 could effectively trigger activation and differentiation of B-CLL cells in all cases as inferred by the induction of morphological changes, RNA synthesis, and monotypic Ig production. Addition of calcium ionophore A23187 to bryostatin 1- exposed cells resulted in significantly increased values for RNA synthesis and Ig production and in the acquisition of plasmacytoid morphology. Bryostatin 1 and the dual signal of bryostatin 1 plus A23187 mimicked the stimulatory action of TPA and the combination of TPA plus A23187, respectively. Overall, bryostatin 1 was less active than equivalent concentrations of TPA. This lesser efficacy may, however, reflect a quantitative rather than qualitative difference. Bryostatin 1 partially antagonized TPA-mediated effects on B-CLL cells suggesting different modes of action by the two activators. These studies indicate that bryostatin 1 has effective differentiation- inducing properties on B-CLL cells that can differentiation-inducing properties on B-CLL cells that can be accentuated by a calcium ionophore.
Detection of minimal residual disease in acute lymphoblastic leukemia by in vitro amplification of rearranged T-cell receptor delta chain sequences
Authors: Hansen-Hagge TE , Yokota S , Bartram CR
Published: October 2019

Human T-cell receptor (TCR) delta-chain diversity mainly originates from high junctional variability, since only a limited number of germline elements is available. This extraordinary diversity at the V.J junction, due to the use of two D delta elements and extensive incorporation of N nucleotides, constitutes a specific clonal marker for cell populations exhibiting rearranged TCR delta genes. To this end we amplified in vitro by polymerase chain reaction (PCR) the TCR delta junctional region of five acute lymphoblastic leukemias (ALL), isolated respective DNA fragments, and used them directly as clonospecific probes. The combination of PCR technology and hybridization to clonospecific probes permitted the detection of leukemia DNA at dilution of 1:100,000 in all five cases. Moreover, we were able to investigate one of the ALL patients 11 months after achieving continuous complete remission. Conventional Southern blot analysis failed to detect rearranged TCR genes at this stage. However, residual leukemic cells could readily be detected by PCR technique. We conclude that the strategy proposed here is a very sensitive tool to detect minimal residual disease in a significant proportion of human lymphoid neoplasias.
Multipotent stem cell involvement in megakaryoblastic leukemia: cytologic and cytogenetic evidence in 15 patients
Authors: Cuneo A , Mecucci C , Kerim S , Vandenberghe E , Dal Cin P , Van Orshoven A , Rodhain J , Bosly A , Michaux JL , Martiat P
Published: October 2019

Cytologic and cytogenetic results obtained from patients fulfilling the FAB criteria for the diagnosis of acute nonlymphocytic leukemia (ANLL) of megakaryocytic lineage (ANLL-M7) are reported. Eleven cases were de novo ANLL-M7, of whom three presented with acute myelofibrosis. Four cases were megakaryoblastic transformations of chronic myelogenous leukemia (two cases), refractory anemia with excess of blasts (one case), and polycythemia vera (one case). Four patients showed a minority of granular blasts, with occasional Auer rods in one. Positive myeloperoxidase and/or sudan black-B stainings and CD13 positivity in these cases were consistent with the presence of a myeloid involvement. Morphologic evidence of associated myelodysplastic features was detected in all evaluable patients with de novo ANLL-M7. These cytologic findings indicate that ANLL-M7 may frequently represent a multilineage proliferation. Cytogenetic studies revealed -7/7q- and +8, alone or in combination with additional aberrations, in three cases each. Rearrangements involving bands 3q21 or 3q26 were seen in two patients and +21, as an additional aberration, in one. Other structural rearrangements all observed in a single patient were inv(16)(p13q22) at megakaryoblastic relapse with bone marrow eosinophilia, t(13;20)(q13 or 14;q11), del(20)(q11), and der(7)t(7;17)(p14;q22). Most breakpoints of these aberrations are located at bands frequently rearranged in malignant myeloid stem cell disorders. A review of 31 cases of the literature showed a frequent occurrence of -7/7q- and -5/5q- in ANLL- M7. Many of the chromosome aberrations so far described in ANLL-M7 appear to be shared by a spectrum of myeloid neoplasias and may be related to mechanisms conferring proliferative advantage to undifferentiated stem cells.
Acceleration of hemoglobin C crystallization by hemoglobin S
Authors: Lin MJ , Nagel RL , Hirsch RE
Published: October 2019

We previously reported that circulating hemoglobin (Hb) CC erythrocytes contain oxygenated HbC crystals with little or no HbF and that HbF inhibits in vitro crystallization of HbC. We now report that HbS accelerates in vitro crystallization of HbC. Crystals were formed in 1.8 mol/L potassium phosphate buffer, pH 7.4, at 30 degrees C and were counted in several time intervals with a hematocytometer. The hemoglobin composition of Millipore-isolated crystals and supernatant were also analyzed. Under the conditions selected, 100% HbS formed needle-shaped crystals only after two hours. Pure HbC does not form crystals within 15 minutes, whereas a ratio of 10% HbS:90% HbC forms 1,100 crystals/mm3, 20% HbS:80% HbC forms 370 crystals/mm3, and 30% HbS:70% HbC forms 5 crystals/mm3. Crystals formed in the presence of HbS are tetragonal, as are pure HbC crystals. As compared with 100% HbC, HbA or albumin mixed with HbC showed a decreased number of crystals as a result of dilution. Analysis of the Hb content of isolated crystals by citrate agar gel electrophoresis showed that HbS was rapidly incorporated into the crystal in the same ratio over time. These results demonstrate that HbS accelerates crystallization of HbC with respect to the rates of crystallization of any of these two Hbs separately, through a mechanism that involves cocrystallization. These results may be significant in understanding SC disease.
Inhibition of malarial parasite invasion by monoclonal antibodies against glycophorin A correlates with reduction in red cell membrane deformability
Authors: Pasvol G , Chasis JA , Mohandas N , Anstee DJ , Tanner MJ , Merry AH
Published: October 2019

The effect of well-characterized monoclonal antibodies to red cell surface molecules on the invasion of human red cells by the malarial parasites Plasmodium falciparum and Plasmodium knowlesi was examined. Antibodies to glycophorin A (GP alpha) inhibit invasion for both parasite species, and this is highly correlated with the degree to which they decrease red cell membrane deformability as measured by ektacytometry. This effect on rigidity and invasion was also seen with monovalent Fab fragments. The closer the antibody binding site was to the membrane bilayer, the greater was its effect on inducing membrane rigidity and decreasing parasite invasion. Antibodies to the Wright determinant in particular were the most inhibitory. This differential effect of the various antibodies was not correlated with their binding affinities or the number of sites bound per cell. Antibodies to surface molecules other than GP alpha were without effect. A novel mechanism is described whereby monoclonal antibodies and their Fab fragments directed at determinants on the external surface of red cells might act to inhibit invasion by malarial parasites by altering membrane material properties.
Effector function for RAS oncogene in interleukin-3-dependent myeloid cells involves diminished efficacy of prostaglandin E1-mediated inhibition of proliferation
Authors: Derigs HG , Klingberg D , Tricot GJ , Boswell HS
Published: October 2019

Leukemic cell growth in the marrow microenvironment may be modulated by stromal cell products, including stimulatory growth factors and the inhibitory regulator prostaglandin E. The production of both of these stromal cell products induced by cytokine mediators appears to be closely linked. Cyclic AMP (cAMP) is an intracellular second messenger that inhibits myeloid cell proliferation and is produced in myeloid leukemia cells on stimulation of adenylate cyclase enzyme by prostaglandin E1 (PGE1). Cells expressing the product of an RAS oncogene have been observed to display diminished hormone-stimulated adenylate cyclase of membranes. If this observation were applicable to myeloid cells, a potentially important mode for leukemia cells expressing p21 RAS to escape inhibitory regulation within the hematopoietic microenvironment would be identified. We studied an interleukin-3 (IL-3)-dependent myeloid cell line, NFS/N1.H7, and a derivative line transfected with H-RAS codon 12 (T24) oncogene, H7 Neo Ras.F3, for inhibition of proliferation by PGE1, 1 microM, alone or in combination with pertussis toxin, which inactivates Gi, an inhibitory regulatory guanosine triphosphate (GTP)-binding protein of adenylate cyclase. NFS/N1.H7 cells were inhibited in interleukin-3-dependent proliferation (dose range, IL-3 10 to 100 U/mL) by PGE1 79 +/- 11%, by pertussis toxin 51 +/- 9%, and by the combination 92 +/- 2%, whereas H7 Neo RAS.F3 was inhibited 51 +/- 7%, 6 +/- 2%, or 58 +/- 9% by PGE1, pertussis toxin, and the combination, respectively. These differences in capacity for inhibition by adenylate cyclase agonists between RAS- transfectant cells (lower inhibition) versus parent cells (greater inhibition) were all highly significant (P less than .0005). Intracellular cAMP formed on PGE1 stimulation of pertussis-intoxicated cells was 150% lower in RAS-transfectant cells than in parent cells. The adenylate cyclase activity of membranes from pertussis-intoxicated RAS-transfected cells was 1.5 to two times lower than that of pertussis- intoxicated parent-cell membranes on Mg2+-dependent activation by hormone and/or guanine nucleotide. However, very similar adenylate cyclase activity was observed in oncogenic p21 RAS-containing membranes compared with parental membranes under conditions of direct activation by 4 mM Mn2+ and forskolin, where inhibitory or stimulatory G-protein influences are minimal. These studies showed diminished adenylate cyclase activity in mutant RAS-bearing myeloid-cell membranes compared with parent-cell membranes independent of the pertussis toxin-sensitive G protein, Gi.(ABSTRACT TRUNCATED AT 400 WORDS).
Comparison of anti-Tac and anti-transferrin receptor-conjugated liposomes for specific drug delivery to adult T-cell leukemia
Authors: Hege KM , Daleke DL , Waldmann TA , Matthay KK
Published: October 2019

Adult T-cell leukemia (ATL) is a rapidly progressive and usually fatal malignancy of mature T cells characterized by the expression of large numbers of interleukin-2 (IL-2) receptors on the cell surface. Anti- Tac, a monoclonal antibody directed against the IL-2 receptor, was conjugated to liposomes and compared with anti-transferrin receptor (anti-TFR) conjugates for specific binding, internalization, and intracellular drug delivery to ATL cells. Two independent assays were used: a fluorimetric assay with liposome encapsulated 1-hydroxypyrene- 3,6,8-trisulfonic acid, a pH-sensitive fluorescent dye, and a growth inhibition assay using methotrexate-gamma-aspartate, a liposome- dependent cytotoxic drug. MT-1 and HUT-102 cell lines derived from patients with ATL were compared with Molt-4, a leukemia cell line that does not express IL-2 receptors in an uninduced state. Fluorimetric studies showed specific binding and internalization of anti-Tac- conjugated liposomes by HUT-102 and MT-1 but not by the Tac-negative cell line Molt-4, demonstrating the lack of nonspecific or Fc receptor- mediated uptake. Anti-TFR-conjugated liposomes were effectively bound and internalized by all three cell lines and consistently showed the highest degree of cellular liposome uptake. Drug-containing liposomes conjugated to anti-Tac were more than tenfold more effective in causing growth inhibition of ATL cells than the nonspecific control conjugates. Anti-Tac conjugates caused minimal growth inhibition of Molt-4 cells over the concentration range effective against the ATL cells. Anti-TFR- coupled liposomes gave better growth inhibition of HUT-102 and MT-1 cells (40- to 60-fold) than anti-Tac conjugates. Both anti-Tac-directed and anti-TFR-directed liposomes are effective for intracellular drug delivery to ATL cells and may represent a useful method of treatment in this disease.
Cellular and membrane properties of alpha and beta thalassemic erythrocytes are different: implication for differences in clinical manifestations
Authors: Schrier SL , Rachmilewitz E , Mohandas N
Published: October 2019

To define how excess unpaired alpha- and beta-globin chains in severe beta-thalassemia and severe alpha-thalassemia interacting with the membrane might alter cellular and membrane properties, we performed a series of biophysical and biochemical analyses on erythrocytes obtained from affected patients. Detailed analysis of cellular and membrane deformability characteristics showed that both forms of thalassemic erythrocytes have excess surface area in relation to cell volume and increased membrane dynamic rigidity. The deformability characteristics of thalassemic erythrocytes in hypertonic media differed significantly from that of normal erythrocytes of identical cell density. These findings suggest that dynamic rigidity of thalassemic erythrocytes is influenced not only by cytoplasmic viscosity determined by cell hemoglobin concentration but also by the extent and type of globin interacting with the membrane. In contrast to the above-noted similarities, major differences were noted in the mechanical stability of the alpha- and beta-thalassemic membranes and in their state of cell hydration. While the mechanical stability of alpha-thalassemic membranes was normal or marginally elevated, the stability of beta- thalassemic membranes was markedly decreased to half the normal value. Cell-density analysis showed that the alpha-thalassemic erythrocytes were uniformly less dense than normal, while beta-thalassemic erythrocytes had a broad-density distribution, with all populations having both lower and higher than normal density values, implying cellular dehydration in beta-thalassemia and not in alpha-thalassemia. Membrane-protein analysis revealed that excess globin chains were bound to the membrane skeletons of both alpha- and beta-thalassemic erythrocytes, with the highest amounts being found in membrane skeletons derived from erythrocytes of splenectomized individuals with beta-thalassemia intermedia. These data demonstrate that interaction of excess alpha- and beta-globin chains with membranes produces different cellular changes and suggest that the observed differences in the pathophysiology of alpha- and beta-thalassemias may be related to different cellular effects induced by the excess in beta- and alpha- globin chains.
Delayed activation of quiescent donor hematopoietic stem cells in the host marrow cavity by anti-host monoclonal antibody
Authors: Sadelain MW , Wegmann TG
Published: October 2019

To understand the mechanisms controlling hematopoietic engraftment in untreated, normal recipients, we investigated the fate of parental, donor hematopoietic stem cells after apparent graft failures in unconditioned F1 hybrid recipient mice. By administering an anti-host H- 2K monoclonal antibody, which targets host cells but spares the donor, we found that chimerism could be induced by delayed conditioning in animals with apparent graft failure. Engraftment kinetics in the host were followed by typing individual colony forming unit-- granulocyte/macrophage (CFU-GM) colonies for their origin and showed that parental cells, which were otherwise virtually absent, become promptly detectable within the marrow cavity after antibody administration. Marrow transfers to secondary hosts suggested that parental stem cells were present in the marrow of the untreated recipients. These findings establish that the elimination of all parental cells cannot account for the absence of peripheral blood chimerism in the unconditioned F1 hybrid recipient. Thus, viable and functional donor stem cells, which remain quiescent in the host marrow, can be activated by a selective conditioning regimen and can rescue an apparent graft failure. The selective activation in vivo of marked stem cells in an unirradiated microenvironment may be a useful system to study the regulation of cellular proliferation within the marrow cavity.
Granulocyte-macrophage colony-stimulating factor is an endogenous regulator of cell proliferation in juvenile chronic myelogenous leukemia
Authors: Gualtieri RJ , Emanuel PD , Zuckerman KS , Martin G , Clark SC , Shadduck RK , Dracker RA , Akabutu J , Nitschke R , Hetherington ML
Published: October 2019

Juvenile chronic myelogenous leukemia (JCML) is a rare myeloproliferative disorder of early childhood that is clinically and cytogenically distinct from the well-recognized adult type of chronic myeloid leukemia. Unlike the adult disease, growth of hematopoietic progenitors from peripheral blood (PB) occurs in the absence of exogenous stimulus even at low cell densities. This so-called “spontaneous”growth can be abrogated by adherent cell depletion and appears to depend on production of endogenous growth factors. We studied seven children with JCML to determine the nature of endogenous stimulators. With isolated PB mononuclear cells (PBMNCs) and a 3H- thymidine (3H-TdR) incorporation assay, JCML cells were shown to incorporate high levels of 3H-TdR when cultured in the absence of stimulus even at low cell densities. When neutralizing antisera prepared against each of the four known colony-stimulating factors (CSFs), GM-CSF, G-CSF, M-CSF, and interleukin-3 (IL-3), as well as antisera against interleukin-1 (alpha and beta) and tumor necrosis factor (TNF) were added to these cultures, only the antisera against recombinant human GM-CSF (rhGM-CSF) consistently resulted in significant inhibition of cell proliferation, achieving up to 72% inhibition of 3H-TdR incorporation in one case. Monoclonal antibodies (MoAbs) against rhGM-CSF resulted in a similar and highly significant degree of inhibition. A marked inhibitory effect of rhGM-CSF antiserum on “spontaneous” growth of PB CFU-GM derived colonies in semisolid medium was also demonstrated in four of five patients studied (87% to 90% inhibition). Production of growth factors by highly enriched JCML monocytes was variable. When initially studied in five of the seven patients, the monocytes from three of the patients revealed increased release of IL-1-like activities; two patients had levels similar to those of controls. One patient with normal levels when initially studied was later shown to have markedly increased amounts of IL-1-like activities in a second preparation of monocyte-conditioned medium (MCM). High levels of GM-CSF were detected in the initial MCM from one patient, but this may have indirectly reflected elevated IL-1-like activities present in the MCM. IL-3 and M-CSF levels were either low or undetectable in the patients studied as compared with MCM prepared with normal adult monocytes. These results clearly implicate GM-CSF as the primary endogenous regulator of JCML cell proliferation in culture and suggest that this malignant myeloproliferative disease may in part result from paracrine stimulation of marrow progenitor cells by growth factors/cytokines secreted by the malignant monocytes.
Hematopoiesis in vitro coexists with natural killer lymphocytes
Authors: Niemeyer CM , Sieff CA , Smith BR , Ault KA , Nathan DG
Published: October 2019

The role of natural killer (NK) lymphocytes in the regulation of human hematopoiesis is controversial. NK-mediated inhibition of colony formation of hematopoietic progenitor cells has been irregularly reported for various cell lineages. In an effort to clarify such disparate findings, we studied the interaction of clearly defined NK and partially purified progenitor cell populations. Cell sorter purified CD16 positive blood NK cells and enriched autologous marrow progenitors were co-incubated at various lymphocyte to marrow cell ratios and then cultured in methylcellulose. There was no inhibition of myeloid, erythroid, or mixed colony formation. Similarly, activation of CD16 positive lymphocytes by interleukin-2 (IL-2) before co-incubation and co-culture did not result in inhibition of colony formation. Furthermore, in a newly designed assay system, we demonstrated that NK cells, which did not modulate colony-formation, remained capable of recognizing and killing rare K562 target cells seeded within the marrow cell population. Our results indicate that unstimulated and IL-2 activated isolated blood NK cells coexist with functioning autologous marrow progenitors in vitro.
Fibrinogen Kyoto III: a congenital dysfibrinogen with a gamma aspartic acid-330 to tyrosine substitution manifesting impaired fibrin monomer polymerization
Authors: Terukina S , Yamazumi K , Okamoto K , Yamashita H , Ito Y , Matsuda M
Published: October 2019

A congenital dysfibrinogen characterized by impaired fibrin monomer polymerization was found in an asymptomatic 50-year-old woman and her two sons. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) run according to the method of Laemmli, we noticed two gamma chain species in fibrinogen and its plasmic fragments D1 and D2, consisting of a normal species and an apparently lower molecular weight (mol wt) variant in respective fractions. However, in fragment D3 only a single gamma chain remnant was observed. By chromatofocusing of the plasmic-CaCl2 digests of the abnormal fibrinogen, we separately isolated the normal and abnormal D1 species, the latter having been eluted in a slightly higher pH range. As expected, the abnormal D1 species failed to interfere with thrombin clotting of normal fibrinogen and normal fibrin monomer polymerization, whereas the normal D1 species inhibited them markedly. By analyzing the lysyl endopeptidase digests of the isolated gamma chain, we identified a replacement of aspartic acid by tyrosine at position 330 of the mutant gamma chain. The point mutation from an aspartic acid (pK for the beta-carboxyl = 3.86) to a tyrosine (pK for the aromatic hydroxyl = 10.07) may have perturbed the folding gamma chain structure in the D domain of fibrinogen specifically required for polymerization.
Identification of vitronectin as a major plasma protein adsorbed on polymer surfaces of different copolymer composition
Authors: Bale MD , Wohlfahrt LA , Mosher DF , Tomasini B , Sutton RC
Published: October 2019

The arrays of proteins adsorbed from plasma onto a series of polystyrene copolymeric latexes were analyzed by enzyme-linked immunosorbent assay (ELISA) of washed beads and immunoblotting of proteins desorbed from the beads and separated by polyacrylamide gel electrophoresis (PAGE). Beads were prepared by continuous emulsion polymerization in the absence of surfactant. Coomassie brilliant blue staining of gel electropherograms of desorbed proteins indicated that the presence of small amounts of comonomers (1 to 10 mole %) significantly influenced the composition of the adsorbed protein layer. Immunoblotting revealed that fibrinogen, fibronectin, and vitronectin were adsorbed by all surfaces investigated. C3 and Clq adsorption varied significantly with copolymer composition. The ELISAs revealed that although the concentrations of vitronectin and fibronectin in plasma are similar, the extent of vitronectin adsorption from 70% to 85% plasma was greater by two orders of magnitude than fibronectin adsorption. Vitronectin adsorbed on carboxylic acid-containing copolymers reacted more strongly with a conformationally sensitive antivitronectin monoclonal antibody (MoAb) than vitronectin adsorbed to polystyrene and was more susceptible to cleavage by plasma proteases(s). The results show that vitronectin is a major protein adsorbed from concentrated plasma and that small changes in the chemical composition of a copolymer profoundly affects the extent and nature of protein adsorption from complex mixtures such as plasma.
Rearrangement and expression of p53 in the chronic phase and blast crisis of chronic myelogenous leukemia
Authors: Mashal R , Shtalrid M , Talpaz M , Kantarjian H , Smith L , Beran M , Cork A , Trujillo J , Gutterman J , Deisseroth A
Published: October 2019

We tested a population of over 60 patients with chronic myelogenous leukemia (CML) for changes in the structure and expression of the p53 gene, which is located on chromosome 17. Six of 27 (22%) blast crisis samples and 3 of 5 (60%) accelerated phase samples had rearrangements of chromosome 17, whereas only 3 of 42 (7%) chronic phase patients had cytogenetic changes in chromosome 17. There was no loss of heterozygosity during the transition to blastic crisis among seven individuals who were informative for polymorphic probes for regions in or around the p53 gene on 17p. One patient in the chronic phase and one patient in the blastic phase of the 61 CML patients studied exhibited rearrangements of the p53 gene that were detectable by Southern analysis. One p53 allele was rearranged in the chronic phase patient and both p53 alleles were rearranged in the blastic phase patient. The p53 messenger RNA (mRNA) was of normal size (2.8 kb) in chronic phase and blast crisis, and the expression of the p53 gene was at least as high or higher in blast crisis as in the chronic phase of CML. The high incidence of abnormalities of chromosome 17 in blast-crisis CML found in our studies and the discovery of rearrangements of the p53 gene in two CML patients studied suggest that further study with probes for the p53 gene and anonymous polymorphic sites in chromosome 17 should be conducted in CML.
Enzymatic evidence for differences in the placement of Rh antigens within the red cell membrane
Authors: Suyama K , Goldstein J
Published: October 2019

Intact erythrocytes of different Rh genotypes were subjected to various enzyme treatments, the effects of which were monitored by separating the membrane proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and performing Western blotting using an antibody preparation that recognizes only Rh-related polypeptides. We found that treatment of intact cells with either phospholipase A2 or proteases such as papain did not alter the size of Rh antigen-containing polypeptides. In contrast, phospholipase A2 treatment followed by papain digestion cleaved a fraction of these polypeptides. This cleavage appears, from such digestions of Rh(D) positive and negative cells of different genotypes, to occur solely at the extracellular domain of Rh(D) polypeptide, while the extracellular domains of other Rh antigen-containing polypeptides are unaffected. Digestion of red blood cell ghosts and inside-out vesicles with trypsin showed that Rh(D), (C/c), and (E/e) antigen-containing polypeptides span the lipid bilayer having cytoplasmic domains susceptible to the action of proteases. The size of the cleavage products at the cytoplasmic domain of -D-/-D- cells was found to differ from that of other Rh(D) positive genotypes, due possibly to a difference in folding of Rh(D) polypeptide at its cytoplasmic domain and within the cellular membrane of these cells.
Modulation of spontaneous outgrowth of Epstein-Barr virus immortalized B-cell clones by granulocyte-macrophage colony-stimulating factor and interleukin-3
Authors: Paul CC , Baumann MA
Published: October 2019

Spontaneous outgrowth of immortalized Epstein-Barr virus (EBV) infected B-cell clones will occur from cultures of peripheral blood mononuclear cells (PBMNCs) of some persons with a history of EBV infection. We determined that outgrowth of such clones may be reproducibly modulated by supplementation of cultures with the hematopoietic growth factors GM- CSF and interleukin-3 (IL-3). Continuous supplementation of cultures with GM-CSF facilitates emergence of immortalized B-cell clones, whereas supplementation with IL-3 completely prevents their emergence. The effect of GM-CSF may be direct, at least in part, as the proliferation of pure clones of EBV-transformed B lymphocytes was augmented in response to GM-CSF. An indirect mechanism appears to be responsible for the inhibition of transformed B-cell outgrowth in response to IL-3, as IL-3 had no inhibitory effect on proliferation of pure transformed B-cell clones and IL-3-mediated inhibition could be eliminated by antibody neutralization of gamma-interferon (gamma-IFN) or tumor necrosis factor-alpha (TNF-alpha) early in culture. The mechanisms of these effects deserve further study and may have clinical relevance to use of hematopoietic growth factors for support of bone marrow (BM) function in immunocompromised patients.
Human B cells express two types of interleukin-1 receptors
Authors: Benjamin D , Dower SK
Published: October 2019

Several reports demonstrate that interleukin-1 alpha (IL-1 alpha) and interleukin-1 beta (IL-1 beta), although distantly related at the primary sequence level, bind to the same receptor. This raises the question of what separation, if any, there might be between their biologic activities. Receptor binding assays and cross-competition studies in three Epstein Barr virus (EBV) positive cell lines showed that a subset of IL-1 receptors may bind IL-1 alpha preferentially and that a separate subset may bind IL-1 beta preferentially. Crosslinking studies with 125I-IL-1 alpha or 125I-IL-1 beta demonstrated the expression of both relative molecular mass (Mr) 80,500 IL-1 receptor, known to be T cell-specific, and Mr 69,500 IL-1 receptor, recently detected on B-cell lineage only. Whether the high affinity binding sites correspond to Mr 80,500 and the low affinity binding sites to Mr 69,500 remains to be elucidated.