bluuebunny/crossref_metadata_2025_split huggingface dataset:
Critical Requirement for Graft Passenger Leukocytes in Allograft Tolerance Induced by Donor Blood Transfusion
Authors: Josien Régis , Heslan Michèle , Brouard Sophie , Soulillou Jean-Paul , Cuturi Maria-Cristina 
Published: October 2019

AbstractTolerance to a vascularized allograft can be induced in adult animals by pregraft donor-specific blood transfusion (DST). Mechanisms underlying this effect appear to depend on unresponsiveness of alloreactive T-helper cells. In this study, we examined the roles of DST and cellular components of the allograft that are important in inducing T-cell unresponsiveness in a rat model. DST alone did not tolerize alloreactive recipient T-helper cells, but the combination of DST and heart allograft induced profound inhibition of the antidonor proliferative response in spleen but not in lymph node cells. When heart allografts were depleted of passenger leukocytes by pretreating the donor with cyclophosphamide or by parking the graft for 2 months in a tolerant recipient, tolerance induction in DST-treated recipients was abrogated. Tolerance could then be restored in a majority of DST-treated recipients of passenger leukocytes depleted grafts by injecting them at the time of grafting with donor, but not third-party, dendritic cells. This indicates that graft passenger leukocytes, most likely dendritic cells, are required for DST-induced allograft tolerance.
Blood Cells With Reduced Mitochondrial Membrane Potential and Cytosolic Cytochrome C Can Survive and Maintain Clonogenicity Given Appropriate Signals to Suppress Apoptosis
Authors: Chen Quan , Takeyama Naoshi , Brady Ged , Watson Alastair J.M. , Dive Caroline 
Published: October 2019

AbstractReduction of mitochondrial membrane potential (Ψm) and release of cytochrome c from mitochondria appear to be key events during apoptosis. Apoptosis was induced in IC.DP premast cells by the withdrawal of interleukin-3 (IL-3). Ψm decreased by 12 hours and cytochrome c was detected in the cytosol at 18 hours. Despite these changes in the mitochondria after 18 hours of IL-3 deprivation, clonogenicity was unaffected when IL-3 was replenished at 18 hours. Activation of v-Abl tyrosine kinase (v-Abl TK) in IC.DP cells before IL-3 depletion led to increased levels of Bcl-XL, prevented reduction of Ψm and the release of mitochondrial cytochrome c, and suppressed apoptosis. Activation of v-Abl TK 18 hours after withdrawal of IL-3 when ≤10% of the cells had died restored Ψm in the remaining cells. More than 40% of cells thus rescued by v-Abl TK between 18 and 42 hours could subsequently form colonies in the presence of IL-3. These data suggest that reduction in Ψm precedes loss of mitochondrial cytochrome c in IC.DP cells; that v-Abl TK activation, probably via upregulation of Bcl-XL, prevents loss of Ψm and blocks the release of cytochrome c from mitochondria; and that neither of these mitochondrial events is sufficient for commitment to apoptosis.
Pregnancy-Associated Thrombocytopenia Revisited: Assessment and Follow-Up of 50 Cases
Authors: Ajzenberg Nadine , Dreyfus Marie , Kaplan Cécile , Yvart Jeannine , Weill Bernard , Tchernia Gil 
Published: October 2019

Abstract
Thrombocytopenia detected during pregnancy addresses the issue of its mechanism and of the possible occurrence of neonatal thrombocytopenia. To further investigate these issues, 50 women referred to us because of thrombocytopenia detected during pregnancy (platelet count, &lt;150 × 109/L), were extensively studied, as well as their offspring. Among these thrombocytopenic women, we used the threshold of 70 × 109/L to differentiate between mild and severe thrombocytopenia. Whatever the severity of thrombocytopenia, we found biological features of an autoimmune disorder in 48% of the women, and chronic thrombocytopenia in 55%. A familial thrombocytopenia was evidenced in 1 case. These 50 women gave birth to 63 neonates, among whom 24 were thrombocytopenic, either at birth or during the first week of life. Neonatal thrombocytopenia could only be predicted in multiparous women, on the basis of previous neonatal thrombocytopenia in older siblings, and/or when maternal platelet life span study, performed before pregnancy, had evidenced an autoimmune thrombocytopenia (AITP)-like profile. These results suggest that, in case of pregnancy-associated thrombocytopenia, familial and immunological studies, combined with postdelivery iterative platelet counts, should be performed to properly characterize the thrombocytopenia. Moreover, the platelet count of the neonate should be carefully assessed at birth and during the following days, a platelet life span study should be performed after delivery in the mother, because these two parameters are likely to bring valuable information regarding the forthcoming pregnancies and the risk of neonatal thrombocytopenia.
Structurally Specific Heparan Sulfates Support Primitive Human Hematopoiesis by Formation of a Multimolecular Stem Cell Niche
Authors: Gupta Pankaj , Oegema Theodore R. , Brazil Joseph J. , Dudek Arkadiusz Z. , Slungaard Arne , Verfaillie Catherine M. 
Published: October 2019

AbstractStem cell localization, conservation, and differentiation is believed to occur in niches in the marrow stromal microenvironment. Our recent observation that long-term in vitro human hematopoiesis requires a stromal heparan sulfate proteoglycan (HSPG) led us to hypothesize that such HSPG may orchestrate the formation of the stem cell niche. We compared the structure and function of HS from M2-10B4, a hematopoiesis-supportive cell line, with HS from a nonsupportive cell line, FHS-173-We. Long-term culture-initiating cell (LTC-IC) maintenance was enhanced by PG from supportive cells but not by PG from nonsupportive cells (P &lt; .005). The supportive HS were significantly larger and more highly sulfated than the nonsupportive HS. Specifically, supportive HS contained higher 6-O-sulfation on the glucosamine residues. In agreement with these observations, purified 6-O-sulfated heparin and highly 6-O-sulfated bovine kidney HS similarly maintained LTC-IC. In contrast, completely desulfated heparin, N-sulfated heparin, and unmodified heparin did not support LTC-IC maintenance. Moreover, the supportive HS promoted LTC-IC maintenance but not differentiation of CD34+/HLA-DR−cells into colony-forming cells (CFCs) and mature blood cells. The supportive HS but not the nonsupportive HS bound both cytokines and matrix components critical for hematopoiesis, including interleukin-3 (IL-3), macrophage inflammatory protein-1 (MIP-1), and thrombospondin (TSP). Significantly more CD34+ cells adhered directly to immobilized O-sulfated heparin than to N-sulfated or desulfated heparin. Thus, hematopoiesis-supportive stromal HSPG possessing large, highly 6-O-sulfated HS mediate the juxtaposition of hematopoietic progenitors with stromal cells, specific growth-promoting (IL-3) and growth-inhibitory (MIP-1 and platelet factor 4 [PF4]) cytokines, and extracellular matrix (ECM) proteins such as TSP. We conclude that the structural specificity of stromal HSPG that determines the selective colocalization of cytokines and ECM components leads to the formation of discrete niches, thereby orchestrating the controlled growth and differentiation of stem cells. These findings may have important implications for ex vivo expansion of and gene transfer into primitive hematopoietic progenitors.
Transgenic Mice for MTCP1 Develop T-Cell Prolymphocytic Leukemia
Authors: Gritti Catherine , Dastot Hélène , Soulier Jean , Janin Anne , Daniel Marie-Thérèse , Madani Ali , Grimber Gisèle , Briand Pascale , Sigaux François , Stern Marc-Henri 
Published: October 2019

Abstract
T-cell prolymphocytic leukemia (T-PLL) is a rare form of mature T-cell leukemia associated with chromosomal rearrangements implicatingMTCP1 or TCL1 genes. These genes encode two homologous proteins, p13MTCP1 and p14TCL1, which share no similarity with other known protein. To determine the oncogenic role of MTCP1, mice transgenic for MTCP1under the control of CD2 regulatory regions (CD2-p13 mice) were generated. No abnormality was detected during the first year after birth. A late effect of the transgene was searched for in a cohort of 48 CD2-p13 mice aged 15 to 20 months, issued from 3 independent founders. Lymphoid hemopathies, occurring in the three transgenic lines, were characterized by lymphoid cells with an irregular nucleus, a unique and prominent nucleolus, condensed chromatin, a basophilic cytoplasm devoid of granules, and an immunophenotype of mature T cells. The molecular characterization of Tcrb rearrangements demonstrated the monoclonal origin of these populations. Histopathological analysis of the cohort demonstrated early splenic and hepatic infiltrations, whereas lymphocytosis and medullar infiltrations were found infrequently. The engraftment of these proliferations in H2-matched animals demonstrated their malignant nature. Cumulative incidence of the disease at 20 months was 100%, 50%, and 21% in F3, F4, and F7 lines, respectively, and null in the control group. The level of expression of the transgene, as estimated by Western blotting in the transgenic lines correlated with the tumoral incidence, with the highest expression of p13MTCP1 being found in F3 mice. CD2-p13 transgenic mice developed an hemopathy similar to human T-PLL. These data demonstrate that p13MTCP1 is an oncoprotein and that CD2-p13 transgenic mice represent the first animal model for mature T-PLL.
Role of GATA-1 in Proliferation and Differentiation of Definitive Erythroid and Megakaryocytic Cells In Vivo
Authors: Takahashi Satoru , Komeno Takuya , Suwabe Naruyoshi , Yoh Keigyo , Nakajima Osamu , Nishimura Sigeko , Kuroha Takashi , Nagasawa Toshiro , Yamamoto Masayuki 
Published: October 2019

AbstractTo elucidate the contributions of GATA-1 to definitive hematopoiesis in vivo, we have examined adult mice that were rendered genetically defective in GATA-1 synthesis (Takahashi et al, J Biol Chem272:12611, 1997). Because the GATA-1 gene is located on the X chromosome, which is randomly inactivated in every cell, heterozygous females can bear either an active wild-type or mutant (referred to asGATA-1.05) GATA-1 allele, consequently leading to variable anemic severity. These heterozygous mutant mice usually developed normally, but they began to die after 5 months. These affected animals displayed marked splenomegaly, anemia, and thrombocytopenia. Proerythroblasts and megakaryocytes massively accumulated in the spleens of the heterozygotes, and we showed that the neomycin resistance gene (which is the positive selection marker in ES cells) was expressed profusely in the abnormally abundant cells generated in the GATA-1.05 mutant females. We also observed hematopoiesis outside of the bone marrow in the affected mutant mice. These data suggest that a small number of GATA-1.05 mutant hematopoietic progenitor cells begin to proliferate vigorously during early adulthood, but because the cells are unable to terminally differentiate, this leads to progenitor proliferation in the spleen and consequently death. Thus, GATA-1 plays important in vivo roles for directing definitive hematopoietic progenitors to differentiate along both the erythroid and megakaryocytic pathways. The GATA-1 heterozygous mutant mouse shows a phenotype that is analogous to human myelodysplastic syndrome and thus may serve as a useful model for this disorder.
A Novel Asn344 Deletion in the Core Domain of Coagulation Factor XIII A Subunit: Its Effects on Protein Structure and Function
Authors: Kangsadalampai Sasichai , Chelvanayagam Gareth , Baker Rohan T. , Yenchitsomanus Pa-thai , Pung-amritt Parichat , Mahasandana Chularatana , Board Philip G. 
Published: October 2019

AbstractIn this study a previously undescribed 3 bp deletion, AAT1030-1032, in the factor XIII A subunit gene, has been detected in a Thai patient. The inframe deletion results in the translation of a factor XIII A subunit that lacks Asn344. This is the first inframe deletion to be identified in the factor XIII A subunit gene because six previously reported deletions have all caused frameshifts. The deletion has been introduced into a factor XIII A subunit cDNA and the deleted polypeptide expressed in yeast. The mRNA encoding the mutant enzyme appears to have normal stability but the translated protein is subject to premature degradation. In addition, the mutated enzyme exhibited very little transglutaminase activity compared with the wild-type enzyme. Structural modeling of the deleted enzyme suggests that the absence of Asn344 would have a potent impact on the catalytic activity by reorienting the residues associated with the catalytic center. Thus, the Asn344 deletion strongly confirms the significance of the residues surrounding the catalytic center of the factor XIII A subunit.
In Vivo Expression of Murine Platelet Glycoprotein Ibα
Authors: Fujita Hiroyuki , Hashimoto Yoshimi , Russell Susan , Zieger Barbara , Ware Jerry 
Published: October 2019

AbstractWe have performed a systematic in vivo evaluation of gene expression for the glycoprotein (GP) Ibα subunit of the murine platelet adhesion receptor, GP Ib-IX-V. This study is warranted by in vitro observations of human GP Ibα expression in cells of nonhematopoietic lineage and reports of regulation of the GP Ibα gene by cytokines. However, an in vivo role for a GP Ib-IX-V receptor has not been established beyond that described for normal megakaryocyte/platelet physiology and hemostasis. Our Northern analysis of mouse organs showed high levels of GP Ibα mRNA in bone marrow with a similar expression pattern recapitulated in mice containing a luciferase transgene under the control of the murine GP Ibα promoter. Consistently high levels of luciferase activity were observed in the two hematopoietic organs of mice, bone marrow (1,400 relative light units/μg of protein [RLUs]) and spleen (500 RLUs). Reproducible, but low-levels of luciferase activity were observed in heart, aorta, and lung (30 to 60 RLUs). Among circulating blood cells, the luciferase activity was exclusively localized in platelets. No increase in GP Ibα mRNA or luciferase activity was observed after treatment of mice with lipopolysaccharides (LPS) or tumor necrosis factor-α (TNF-α). We conclude the murine GP Ibα promoter supports a high level of gene expression in megakaryocytes and can express heterologous proteins allowing an in vivo manipulation of platelet-specific proteins in the unique environment of a blood platelet.
Lack of Clinically Significant Contact System Activation During Platelet Concentrate Filtration by Leukocyte Removal Filters
Authors: Scott Cheryl F. , Brandwein Harvey , Whitbread John , Colman Robert W. 
Published: October 2019

AbstractWhen blood (plasma) contacts certain foreign surfaces, factor XII can activate and trigger a series of reactions leading to cleavage of kininogens with subsequent release of bradykinin. In this study, we investigated two different widely used leukocyte removal filters, Pall PXL8K (A) and Asahi PLS-5A (B), to test whether clinically significant contact activation occurred during leukodepletion of platelet-rich plasma (PRP). Kininogens were measured by particle concentration fluorescence immunoassay (PCFIA), which can detect cleavage of high and low molecular weight kininogens (HK and LK), the parent molecules of bradykinin, to determine if contact activation had occurred. A slight, nonsignificant decrease in HK and LK was observed with filter A after the first 5 mL was filtered that returned to prefiltration levels by the end of the filtration. Specific TotK (the combined measurement of HK and LK heavy chains divided by plasma protein concentration) showed a small, significant decrease with filter A after the first 5 mL of platelet concentrates was filtered that returned to prefiltration levels by the end of the filtration. There were no significant increases or decreases in the cleaved kininogen index (CKI), an index of HK proteolytic activation or HK and LK destruction (with release of bradykinin). These data suggest that small amounts of both HK and LK initially adsorb to filter A and then desorb, primarily intact. These data also indicate that no significant contact activation, as measured by PCFIA, occurs during leukodepletion of platelet concentrates with either filter A or B.
Six Previously Undescribed Pyruvate Kinase Mutations Causing Enzyme Deficiency
Authors: Demina Anna , Varughese Kottayil I. , Barbot José , Forman Linda , Beutler Ernest 
Published: October 2019

AbstractErythrocyte pyruvate kinase deficiency is the most common cause of hereditary nonspherocytic hemolytic anemia. We present 6 previously undescribed mutations of the PKLR gene associated with enzyme deficiency located at cDNA nt 476 G→T (159Gly→Val), 884 C→T (295Ala→Val), 943 G→A (315Glu→Lys), 1022 G→A (341Gly→Asp), 1511 G→T (504Arg→Leu), and 1528 C→T (510Arg→Ter). Two of these mutations are near the substrate binding site: the 315Glu→Lys (943A) mutation may be involved in Mg2+ binding and159Gly→Val (476T) mutation has a possible effect on ADP binding. Four of six mutations produce deduced changes in the shape of the molecule. Two of these mutations,504Arg→Leu (1511T) and510Arg→Ter (1528T), are located at the interface of domains A and C. One of them (510Arg→Ter) is a deletion of the C-terminal residues affecting the integrity of the protein. The 504Arg→Leu mutation eliminates a stabilizing interaction between domains A and C. Changes in amino acid 341(nt 1022) from Gly to Asp cause local perturbations. The mutation295Ala→Val (884T) might affect the way pyruvate kinase interacts with other molecules. We review previously described mutations and conclude that there is not yet sufficient data to allow us to draw conclusions regarding genotype/phenotype relationship.
Full Activity From Human β-Globin Locus Control Region Transgenes Requires 5′HS1, Distal β-Globin Promoter, and 3′ β-Globin Sequences
Authors: Pasceri Peter , Pannell Dylan , Wu Xiumei , Ellis James 
Published: October 2019

Abstract
The locus control region (LCR) activates high-level human β-globin transgene expression. LCR cassettes composed of 5′HS2-4 linked to the 815 bp β-globin proximal promoter do not express fully. Here, we show that LCR (5′HS2-4) β-globin transgenes that also contain either 5′HS1 or the distal promoter fail to express fully in single- and low-copy transgenic mice. In contrast, full expression is obtained in the presence of both 5′HS1 and the distal promoter. Nine factor binding sites were identified in 5′HS1, using in vitro DNaseI footprint and gel retardation assays, and these include a strong Sp1/Sp3 site, four GATA-1 sites, and two sites that encompass an ACTAAC motif. LCR (5′HS1-4) β-globin transgene constructs with the distal promoter deleted or replaced by spacer DNA show that specific distal promoter sequences are required for full expression. An LCR (5′HS1-4) transgene construct with truncated downstream β-globin gene sequences indicates that 3′ sequences also play an important role. These results show that full expression of the β-globin gene directed by the LCR requires 5′HS1, the distal β-globin promoter, and 3′ sequences, and has implications for gene therapy construct design and models of LCR activation.
CD164, a Novel Sialomucin on CD34+ and Erythroid Subsets, Is Located on Human Chromosome 6q21
Authors: Watt Suzanne M. , Bühring Hans-Jörg , Rappold Irene , Chan James Yi-Hsin , Lee-Prudhoe Jane , Jones Tania , Zannettino Andrew C.W. , Simmons Paul J. , Doyonnas Regis , Sheer Denise , Butler Lisa H. 
Published: October 2019

AbstractCD164 is a novel 80- to 90-kD mucin-like molecule expressed by human CD34+ hematopoietic progenitor cells. Our previous results suggest that this receptor may play a key role in hematopoiesis by facilitating the adhesion of CD34+ cells to bone marrow stroma and by negatively regulating CD34+hematopoietic progenitor cell growth. These functional effects are mediated by at least two spatially distinct epitopes, defined by the monoclonal antibodies (MoAbs), 103B2/9E10 and 105A5. In this report, we show that these MoAbs, together with two other CD164 MoAbs, N6B6 and 67D2, show distinct patterns of reactivity when analyzed on hematopoietic cells from normal human bone marrow, umbilical cord blood, and peripheral blood. Flow cytometric analyses revealed that, on average, 63% to 82% of human bone marrow and 55% to 93% of cord blood CD34+ cells are CD164+, with expression of the 105A5 epitope being more variable than that of the other identified epitopes. Extensive multiparameter flow cytometric analyses were performed on cells expressing the 103B2/9E10 functional epitope. These analyses showed that the majority (&gt;90%) of CD34+ human bone marrow and cord blood cells that were CD38lo/− or that coexpressed AC133, CD90(Thy-1), CD117(c-kit), or CD135(FLT-3) were CD164(103B2/9E10)+. This CD164 epitope was generally detected on a significant proportion of CD34+CD71lo/− or CD34+CD33lo/− cells. In accord with our previous in vitro progenitor assay data, these phenotypes suggest that the CD164(103B2/9E10) epitope is expressed by a very primitive hematopoietic progenitor cell subset. It is of particular interest to note that the CD34+CD164(103B2/9E10)lo/−cells in bone marrow are mainly CD19+ B-cell precursors, with the CD164(103B2/9E10) epitope subsequently appearing on CD34lo/−CD19+ and CD34lo/−CD20+ B cells in bone marrow, but being virtually absent from B cells in the peripheral blood. Further analyses of the CD34lo/−CD164(103B2/9E10)+ subsets indicated that one of the most prominent populations consists of maturing erythroid cells. The expression of the CD164(103B2/9E10) epitope precedes the appearance of the glycophorin C, glycophorin A, and band III erythroid lineage markers but is lost on terminal differentiation of the erythroid cells. Expression of this CD164(103B2/9E10) epitope is also found on developing myelomonocytic cells in bone marrow, being downregulated on mature neutrophils but maintained on monocytes in the peripheral blood. We have extended these studies further by identifying Pl artificial chromosome (PAC) clones containing the CD164 gene and have used these to localize the CD164 gene specifically to human chromosome 6q21.© 1998 by The American Society of Hematology.
Characterization of the Role of the Human Granulocyte-Macrophage Colony-Stimulating Factor Receptor α Subunit in the Activation of JAK2 and STAT5
Authors: Doyle Sean E. , Gasson Judith C. 
Published: October 2019

AbstractThe high-affinity human granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor (GMR) consists of an alpha (GMRα) and a common beta (βc) subunit. The intracellular domain of βc has been extensively characterized and has been shown to be critical for the activation of both the JAK/STAT and MAP kinase pathways. The function of the intracellular domain of GMRα, however, is not as well characterized. To determine the role of this domain in GMR signaling, an extensive structure-function analysis was performed. Truncation mutants α362, α371, and α375 were generated, as well as the site-directed mutants αVQVQ and αVVVV. Although α375β, αVQNQβ, and αVVVVβ stimulated proliferation in response to human GM-CSF, the truncation mutants α362β and α371β were incapable of transducing a proliferative signal. In addition, both α371 and αVVVV were expressed at markedly reduced levels, indicating the importance of residues 372 to 374 for proper protein expression. More importantly, we show that GMRα plays a direct role in the activation of the JAK/STAT pathway, and electrophoretic mobility shift assays (EMSA) indicate that both GMRα and βc play a role in determining the STAT5 DNA binding complex activated by the GMR. Thus, the intracellular domain of the human GMRα is important for activation of the JAK/STAT pathway and protein stabilization.© 1998 by The American Society of Hematology.