bluuebunny/crossref_metadata_2025_split huggingface dataset:
MHC-Matched Stem Cell Transplantation in Rhesus Macaques Using a Costimulation Blockade-Based Immunomodulation Platform.
Authors: Kean Leslie S. , Hamby Kelly , Deane Taylor , Pearson Thomas C. , Larsen Christian P. 
Published: October 2019

Abstract
A strategy for producing high-level hematopoietic chimerism after non-myeloablative conditioning has been established in the rhesus macaque. This strategy relies on hematopoietic stem cell transplantation after induction with a non-myeloablative dose of busulfan and blockade of the IL2-receptor in the setting of mTOR inhibition with sirolimus and combined CD28/CD154 costimulation blockade. Hematopoietic stem cells derived from bone marrow and leukopheresis products both were found to be successful in inducing high-level chimerism. When transplants were performed between animals that were totally unmatched at the MHC, mean peripheral blood peak donor chimerism was 81% with a median chimerism duration of 145 days. Additional immune modulation strategies, such as pre-transplant CD8 depletion, donor-specific transfusion, recipient thymectomy or peritransplant deoxyspergualin treatment did not improve the level or durability of chimerism in the setting of these MHC-unmatched transplants. Recipient immunologic assessment suggested that chimerism occurred amidst donor-specific down-regulation of alloreactive T cells, and the reappearance of vigorous T-mediated alloreactivity accompanied rejection of the transplants. Furthermore, viral reactivation constituted a significant transplant-related toxicity and may have negatively impacted the ability to achieve indefinite survival of transplanted stem cells. In order to address the dual complications of lack of indefinite chimerism and viral reactivation, we sought to increase the level of MHC matching between donor and recipient transplant pairs. This necessitated a large-scale analysis of an NIH-sponsored rhesus macaque colony in order to determine the familial relationships and MHC-disparity between potential transplant pairs. We have analyzed over 500 animals from this colony, which has resulted in the first primate transplant series between donors and recipients with known degrees of MHC disparity. Our results suggest that viral reactivation is vastly improved when transplant occurs with even one shared MHC haplotype, but that the current immunomodulation strategy is insufficient to achieve immune tolerance in these haplo-identical transplants. However, we have observed long-term mixed chimerism in fully MHC matched transplant pairs that is stable even years after withdrawl of costimulation blockade-based immunomodulation. These results suggest that costimulation blockade may be an important addition to current immunomodulation strategies for producing stable engraftment after nonmyeloablative pre-transplant preparation, with potential application to non-malignant hematologic diseases and genetic disorders.
Correlation of Peripheral Blood Involvement Measured by Four-Color Flow Cytometry and the Achievement of Molecular Response in Mantle Cell Lymphoma Treated within the Prospectively Randomized Intergroup Trials of the European MCL Network
Authors: Pott Christiane , Boettcher Sebastian , Gesk Stefan , Siebert Reiner , Klapper Wolfram , Hoster Eva , Ritgen Matthias , Unterhalt Michael , Rottenkolber Marietta , Hiddemann Wolfgang , Kneba Michael , Dreyling Martin 
Published: October 2019

Abstract
Two prospectively randomized intergroup trials of the European MCL Network investigating the impact of different combined immuno-chemotherapy protocols for patients with stage II–IV mantle cell lymphoma (MCL) >< 65 yrs followed by autologous stem cell transplantation (PBSCT) for patients <65 yrs and a rituximab or interferone maintenance treatment for patients >65 yrs are currently performed.
Patients and methods: 180 German patients with diagnostic peripheral blood (PB) involvement detectable by consensus IGH PCR were analysed for t(11;14) translocation by FISH and 4-colour Flow Cytometry (FC) at diagnosis as well as molecular response (MR) by quantitative IGH-RQ-PCR after induction. The results were compared to clinical parameters at diagnosis and PFS.
Results: Patients had a median age of 61 years, an elevated LDH in 37%, B-symptoms in 41% and extranodal involvement in 37%. According to the MIPI risk factor score 26% had an adverse, 34% an intermediate and 40% a good prognosis. PB involvement by MCL was demonstrated in 67% (74/111) by t(11;14) FISH and in 97% (152/156) by FC. Detection of MCL cells by FC in PB did not correlate with clinical parameters as stage, LDH, extranodal involvement or bone marrow infiltration. However, median % of MCL cells measured by FC differed significantly with clinical stage (p<0.0001), LDH (p=0.0096) bone marrow infiltration (<0.0001) and MIPI prognostic index (0.0002). MR after induction treatment was achieved in 60% (60/100) of patients and correlated with BM infiltration at diagnosis (p=0.0117). There was a trend for improved PFS in patients achieving MR (PFS 90% vs. 75% at 15 months after induction) however, the observation time is still too short for definitive evaluation.
Conclusion: FC is highly sensitive for detection of PB involvement in MCL and improves staging accuracy. Achievement of MR might be an early indicator for treatment outcome after immuno-chemotherapy in MCL with the potential of defining prognostic subgroups.
Low Dose Rituximab in Adult Patients with Idiopathic Thrombocytopenic Purpura.
Authors: Zaja Francesco , Battista Marta L. , Pirrota Maria T. , Palmieri Salvatore , Montagna Michela , Vianelli Nicola , Cavallin Margherita , Bocchia Monica , Defina Marzia , Ippoliti Micaela , Ferrara Felicetto , Patriarca Francesca , Avanzini Maria A. , Regazzi Mario , Isola Miriam , Soldano Franca , Baccarani Michele , Fanin Renato 
Published: October 2019

Abstract
Rituximab 375 mg/sqm weekly for 4 weeks has significant activity in patients with idiopathic thrombocytopenic purpura (ITP). In this setting, different biological and clinical evidence suggests the possible use of lower doses of Rituximab. Twenty-eight adult patients, median age 43 years (range 16–71 years), with previously treated, active and symptomatic ITP were treated prospectively with Rituximab at the fixed dose of 100 mg iv weekly for 4 weeks. Exclusion criteria were positive HIV, HBsAg and pregnancy test, any B-cell lymphoprolipherative disease or other malignancies. Response assessment was evaluated considering the rate of overall and complete responses (OR = platelet count ≥ 50 x 109/L; CR= platelet count ≥ 100 x 109/L and discontinuation of steroid therapy, if present), the time to response (TTR; time necessary to reach a platelet count ≥ 50 x 109/L), the time to complete response (TCR; time necessary to reach a platelet count ≥ 100 x 109/L) and the duration of response. B-cell count and pharmacokinetics (PK) were monitored and related with clinical outcome. Stepwise logistic regression was used to assess whether response was associated with age, gender, diagnosis-Rituximab interval and basal CD20+ve lymphocytes. Results were considered statistical significant when P ≤ 0.05. All patients completed the therapeutic program receiving the four infusions of Rituximab as scheduled, none experiencing short term toxicity. All patients achieved B-cell depletion. OR and CR were achieved in 21/28 (75%) and 12/28 (43%) patients, respectively. CR rate was associated with younger age (OR=0.92 CI95%[0.85;0.99]). The median TTR and TCR were 31 and 44 days, significantly longer then those observed with standard dose in patients with similar characteristics (Haematologica2003;88:538). After a median follow-up of 11 months (range 3–18), 7/21 (33%) patients relapsed, and 3 needed further treatments. PK data showed a concentration time-course profile of Rituximab that was super-imposable, once corrected for the difference in the dose, to that observed previously in patients treated with standard dose, diseases with a median value of 4.1 micrograms/milliliter (range 0–11.9), 12 weeks after the start of treatment. In patients with ITP, low dose Rituximab led to short and mid-term response rates similar to standard dose but with slower timing of response.
A Comparative Proteomic Analysis of Platelets from Healthy Human Patients and Chronic ITP Patients Receiving AMG 531, a Thrombopoiesis-Stimulating Protein.
Authors: Sloan John M. , Coburn John P. , Bertino Amy M. , Wood Valerie , Kuter David J. 
Published: October 2019

Abstract
AMG 531 is a novel thrombopoiesis-stimulating “peptibody” consisting of an Fc carrier domain linked to 4 identical peptides that bind to and activate Mpl, the human thrombopoietin receptor. It has proven efficacy in raising platelet counts of patients with chronic ITP, and is being evaluated in chemotherapy-induced thrombocytopenia and myelodysplastic syndrome. While platelets from healthy subjects receiving AMG 531 reportedly behave normally in platelet aggregation studies, the effects of this medication on protein expression profiles are not known. The platelets from 12 healthy patients without known platelet defects and 9 chronic ITP patients receiving AMG 531 were isolated and their proteins extracted. Proteins with isoelectric points between pH 3 and 7 were separated by two-dimensional gel electrophoresis and stained with Sypro protein detection reagent. These gels were scanned and compared using Progenesis SameSpots software. In this pH range, there were approximately 5000 unique spots detected, representing individual proteins, isoforms of proteins or cleavage products. On multivariate analysis, approximately 11% of these proteins were expressed at levels significantly different between healthy patients without a known platelet disorder and chronic ITP patients receiving AMG 531. Principal component analysis substantiates these differences and a protein dendrogram has been created. The most significant protein expression differences are identified by tandem mass spectrometry. It is not known if these differences in protein expression represent younger platelets, stimulation of protein synthesis by AMG 531, or altered platelet protein expression as a reflection of the ITP. There is no known clinical correlate of these protein changes.
Reversible Bony Changes after Treatment with Bevacizumab in a Child with Cutaneovisceral Angiomatosis with Thrombocytopenia Syndrome: A Case Report and Review of the Literature.
Authors: Smith Angela R. , Jane Hennessy , Margaret Heisel Kurth , Stephen Nelson C. 
Published: October 2019

Abstract
Cutaneovisceral Angiomatosis with Thrombocytopenia (CAT) syndrome is a rare vascular disorder involving the skin and gastrointestinal tract. Clinical features of CAT syndrome include multiple, discrete skin lesions, gastrointestinal bleeding and thrombocytopenia. CAT syndrome is typically treated with angiogenesis inhibitors like corticosteroids and vincristine. Bevacizumab is a relatively new antiangiogenic agent that is FDA approved as a first-line agent for metastatic carcinoma of the colon or rectum in combination with a 5-FU based regimen. Bevacizumab is a humanized monoclonal antibody that binds all five isoforms of human vascular endothelial growth factor (VEGF) and prevents its interaction with the VEGF receptor. There is currently very little clinical pediatric experience with antiangiogenic agents.
Case: Though subtly symptomatic from birth, our patient was diagnosed with CAT syndrome at four months of age after an episode of grossly bloody stools. After failed therapy with corticosteroids and vincristine, the patient was given bevacizumab 10mg/kg/dose every two weeks for four doses with excellent clinical response. After her fourth dose, a chest radiograph revealed incidental, asymptomatic metaphyseal lesions of the humeri. A complete bone survey revealed similar lesions in the metaphyses of nearly all of her long bones. (Figure 1) Given preclinical data suggesting these lesions could result from the use of VEGF inhibitors, bevacizumab was discontinued. All metaphyseal lesions subsequently resolved. (Figure 2) To our knowledge, this is the first report of bony toxicity in a human receiving bevacizumab. A thorough literature review on VEGF inhibitors revealed no reported cases of metaphyseal lesions or stunted growth in humans receiving VEGF inhibitors. Animal studies, however, suggest this may be possible. Growth plates consist of avascular cartilage that is eventually replaced by bone. This process requires invasion of the cartilage with metaphyseal blood vessels and has been shown to be directed by a VEGF gradient (Nature Medicine1999; 5(6): 623–628). Preclinical studies performed using VEGF inhibitors in monkeys demonstrated reversible physeal dysplasia of the distal femur in the monkeys with open growth plates (Toxicol Pathol, 1999; 27(1): 78–86). We hypothesize that use of the VEGF inhibitor, bevacizumab, in a small child with active epiphyseal growth plates caused the radiographic lesions we observed. It appears that this side effect is reversible, at least after short-term use. We propose that close monitoring for bony toxicity is required for all children receiving bevacizumab and that this drug should be used only with caution in children with active bone growth.
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Constitutively Activated STAT3 Promotes Cell Proliferation and Survival in the Activated B Cell Subtype of Diffuse Large B Cell Lymphomas.
Authors: Ye Bihui Hilda , Ding Beibei Belinda , Yu Jian Jessica , Yu Raymond Y.-L. , Mendez Lourdes M. , Shaknovich Rita , Zhang Yonghui , Cattoretti Giorgio 
Published: October 2019

Abstract
During B cell development, cell proliferation and survival are regulated by stage-specific transcription factors. Accordingly, distinct oncogenic pathways are employed by B cell lymphomas representing different stages of B cell development. Diffuse large B cell lymphoma (DLBCL) contains at least two main phenotypic subtypes, i.e. the germinal center B cell-like (GCB-DLBCL) and the activated B cell-like (ABC-DLBCL) groups. It has been shown that GCB-DLBCL responds favorably to chemotherapy and expresses high levels of BCL6, a transcription repressor known to play a causative role in lymphomagenesis. In comparison, ABC-DLBCL has lower levels of BCL6, constitutively activated NF-kappaB and tends to be refractory to chemotherapy. In this study, we investigated the relationship between BCL6 and STAT3 expression/activation in DLBCL and normal GC B cells. Our results demonstrate that BCL6 directly inhibits transcription of the STAT3 gene by binding to two BCL6 sites in its 5′ regulatory region. As a result, high level STAT3 expression and activation are preferentially detected in ABC-DLBCL and BCL6-negative normal germinal center B cells. Specifically, in tonsillar GCs, STAT3 expression and activation is restricted to a previously uncharacterized subset of BCL6−Blimp-1− B cells in the apical light zone. The location and phenotype of these cells suggest that they are in the process of exiting the BCL6-directed GC program and transitioning to a plasma cell differentiation process governed by Blimp-1. The reciprocal relationship between BCL6 and STAT3 is also conserved in DLBCL such that STAT3 expression and activation is preferentially associated with the BCL6-low, ABC subtype. Most importantly, inactivating STAT3 by either AG490 or small interference RNA in ABC-DLBCL cells inhibits cell proliferation and triggers apoptosis. These phenotypes are accompanied by decreased expression of several known STAT3 target genes, including c-Myc, JunB and Mcl-1, and increased expression of the cell cycle inhibitor p27. In addition to identifying STAT3 as a novel BCL6 target gene, our results define STAT3 activation as a second oncogenic pathway operating in ABC-DLBCL and suggest that blocking STAT3 may be potentially therapeutic in treatment of these aggressive lymphomas.
Human Gamma Globin Gene Regulation in Knock-In Mouse Models of Anemia.
Authors: McConnell Sean C. , Huo Yongliang , Liu Shan-Run , Zhang Ting-Ting , Ulrey Clayton L. , Ryan Thomas M. 
Published: October 2019

Abstract
The generation of transgenic and gene targeted mouse models of human hemoglobinopathies provides valuable opportunities to test mechanisms of human globin gene regulation and experimental therapies. Yet mice do not naturally have a fetal hemoglobin, challenging our ability to adequately model the developmental onset of disease. Transgenic model systems that contain the entire human β-globin locus present obstacles to the study of human globin gene switching, including a fetal to adult globin gene switch that occurs too early in development. The generation of genetically engineered mice with a delayed human γ to β hemoglobin switch has been a major topic of interest for our laboratory. Delayed γ globin gene expression improves the clinical progression in patients as well as animal models with hemoglobinopathies. However, molecular mechanisms involved in globin gene switching are not well understood. In this study the transcriptional and epigenetic regulation of human γ to β hemoglobin switching are analyzed in novel human knock-in (KI) mouse models that complete the switch from fetal to adult hemoglobin after birth. These KI mice were generated by replacement of the adult mouse β-globin genes by homologous recombination in embryonic stem cells with a delayed switching human γ to β globin gene construct. Quantitative real-time PCR and HPLC were used to measure mouse and human embryonic, fetal, and adult globin genes through development and show that we have given the mouse a true fetal hemoglobin. Heterozygous mice express human β-like globin genes at a high level comparable to the adult mouse β globin genes. Mutations responsible for hereditary persistence of fetal hemoglobin (HPFH) in the γ globin promoter recapitulate the human phenotype in KI mice, with over 50 fold γ globin gene upregulation in adults. These HPFH KI mice also display higher γ globin levels at birth and markedly delayed γ globin gene downregulation in the weeks following birth. These studies in KI mice demonstrate that human β-like globin genes interacting with the mouse LCR are regulated in a manner similar to what is seen in humans and may be used to study the mechanisms of globin gene switching. Greater understanding of γ-globin gene regulation will be required for achieving the therapeutic goal of reactivating silenced γ-globin genes to ameliorate severe human hemoglobinopathies.
A Humanized Cooley’s Anemia Mouse Model.
Authors: Huo Yongliang , McConnell Sean C. , Ulrey Clayton L. , Zhang Ting-Ting , Yang Rui , Liu Shan-Run , Ryan Thomas M. 
Published: October 2019

Abstract
Cooley’s Anemia (CA) is a heterogeneous group of inherited disorders all marked by the complete absence of adult β-globin chains in red blood cells (RBCs). Newborns with CA are healthy because of the high level of fetal hemoglobin (HbF) present at birth. As HbF levels decline during the first year of life, the absence of functional adult β-globin genes results in a severe anemia that necessitates the initiation of regular blood transfusions for the remainder of life. CA has been difficult to study in murine models due to the lack of a human fetal hemoglobin equivalent in the mouse. This study reports a novel preclinical animal model of CA that survives solely on human fetal hemoglobin at birth and is blood transfusion dependent for life upon completion of the hemoglobin switch after birth. These humanized CA mice were generated by targeted gene replacement in embryonic stem cells of the adult mouse α-globin genes with human α-globin and the adult mouse β-globin genes with a delayed switching γδβ0-globin gene cassette. The nonfunctional human β0-globin knock-in allele contains a single G to A nucleotide mutation in the first base of intervening sequence 1. Both wild-type and hereditary persistence of fetal hemoglobin (HPFH) promoter mutations were tested in the human γ-globin knock-in allele. Heterozygous knock-in mice exhibit β thalassemia intermedia. Newborn homozygous knock-in mice express 100% human hemoglobin in their RBCs, suffer from ineffective erythropoiesis, survive from one to ten days after birth, and are blood transfusion dependent for adult life. This is the first CA mouse model that recapitulates the temporal onset of the disease in human patients. This CA disease model is useful for the study of the regulation of globin gene expression, synthesis, and switching; development of transfusion and iron chelation therapies; induction of fetal hemoglobin synthesis; and the testing of novel genetic and cell-based therapies for the correction of thalassemia.
Increased Prothrombotic State in Patients with Advancing HIV Disease.
Authors: Lijfering Willem M. , Sprenger Herman G. , Georg Rita R. , van der Meulen Piet A. , van der Meer Jan 
Published: October 2019

Abstract
HIV-infected patients are at high risk for venous and arterial thrombosis. We hypothesized that advancing stages of HIV are associated with thrombophilic abnormalities that could predispose to thrombosis. A total of 109 consecutive HIV infected patients were included in the study and twice screened for currently known thrombophilic defects with a time interval of at least 3 months. Ten percent of HIV infected patients had confirmed decreased protein C levels (< 65 IU/dL), 41% had confirmed elevated factor VIII levels (> 150 IU/dL), 22% had confirmed high fibrinogen levels (> 3.5 g/L) and 60% had a confirmed free protein S deficiency (< 65 IU/dL). Median factor VIII levels were higher in patients with AIDS defining illness compared to non AIDS defining illness (226 IU/dL versus 149 IU/dL; P< 0.001), while median free protein S levels were lower in these subgroups (45 IU/dL, versus 58 IU/dL; P< 0.001). Advancing HIV, stratified by CD4 levels of > 500 cells/μL, 200–500 cells/μL or < 500 cells/μL, respectively, was associated with increasing factor VIII levels, fibrinogen levels and decreasing free protein S levels (Figure 1). When factor VIII levels were < 100 IU/dL, median fibrinogen levels were 2.4 g/L, which was 0.3 g/L lower than when factor VIII levels were 100–150 IU/dL (P=0.033) and 0.9 g/L lower than when factor VIII levels were > 150 IU/dL (P< 0.001). Free protein S levels were 70 IU/dL when factor VIII levels were < 100 IU/dL, which decreased to 60 IU/dL when factor VIII levels were 100–150 IU/dL (P=0.010) and to 52 IU/dL when factor VIII levels were > 150 IU/dL (P< 0.001). We conclude that HIV infected patients have multiple prolonged thrombophilic abnormalities compared to the normal population, which increase with advancing HIV disease, thus providing a biologic mechanism for the increased prevalence of venous and arterial thrombosis in HIV.
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