bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proteomic Analysis of Chronic Malignant B-Cell Derived Microparticles Reveals CD148 as a Potential Antigenic Marker for Mantle Cell Lymphoma Diagnosis.
Authors: Miguet Laurent , Fornecker Luc-Matthieu , Felden Claire , Gervais Carine , Herbrecht Raoul , Sanglier Sarah , van Dorsselaer Alain , Mauvieux Laurent 
Published: April 2020

Abstract
The diagnosis of mature B-cell neoplasms remains difficult in a number of cases, especially leukemic phases of non Hodgkin lymphomas, for which discriminating criteria or marker are often lacking. In order to identify new surface markers, we developed an original proteomic approach based on mass spectrometry analysis of plasma membrane microparticles derived from chronic B-cell lymphoproliferations: chronic lymphocytic leukemia/ small cell lymphoma (CLL/SLL) and mantle cell lymphoma (MCL). The approach consisted of protein extraction from plasma membrane microparticles (MPs), generated following actinomycin D stimulation and recovered using differential centrifugation. The complex protein mixture was further separated using 1D-gel electrophoresis separation and gel bands were systematically cutted at 2 mm intervals, trypsin digested and the resulting peptide mixtures was subsequently analysed by tandem mass spectrometry prior to protein identification. The lists of the proteins obtained for each pathology were then examined with respect to the membrane localization of the proteins in order to fulfill biological requirements needed for its further clinical use. Comparison of the lists of the proteins obtained for each pathology identified CD148, a membrane receptor with phosphatase activity, as a candidate for a discriminating marker detected in MCL but not in CLL in this approach. Flow cytometry studies, performed on 55 patients and 10 controls, showed that an anti-CD148 antibody stained significantly higher MCL (n=22) than CLL/SLL (n=33) circulating cells (p&lt;0.0001). Even if the reason of such a regulated expression of CD148 remains unknown, our results indicate that a medium or high CD148 expression level may exclude the diagnosis of CLL/SLL and high CD148 expression levels may be strongly in favor of MCL diagnosis.
Figure Figure
B-Cell Receptor Profiling Suggests a Limited Number of Antigens Involved in the Pathogenesis of Chronic Lymphocytic Leukemia.
Authors: Binder Mascha , Müller Fabian , Frick Mareike , Wehr Claudia , Pantic Milena , Pfeifer Dietmar , Pasqualini Renata , Arap Wadih , Veelken Hendrik , Mertelsmann Roland H. , Trepel Martin 
Published: April 2020

Abstract
B-cell receptors (BCR) on chronic lymphocytic leukemia (CLL) cells have stereotyped hypervariable regions, categorizing approximately 20% of all patients into one of almost 50 BCR subsets with nearly identical receptors. This suggests common antigen recognition in some CLL patients. We explored the binding pattern of recombinant CLL BCRs Fab fragments by selecting epitope mimicking peptides from phage display libraries. We performed selections with multiple libraries using different peptide lengths and constraints. Selection was successful on seven of nine Fab fragments with at least one library. The selected peptides specifically bound the Fab fragment they were selected on as well as the native BCR expressed on parental CLL cells. Subsequently, we validated in one example that the selected peptide truly mimics an epitope recognized by CLL BCRs. As CLL BCRs have long been suspected of interacting with a set of different antigens, we screened a random panel of CLL cases for binding six representatives of the selected epitope mimics described above. Surprisingly, all CLL samples recognized one or several of the epitope mimics. The majority of CLL samples could be assigned to one of 14 categories with specific epitope binding patterns. These categories were not predictable from the amino acid sequence of the complementarity-determining region 3 although samples expressing homologous BCRs preferentially clustered in the same category. In addition, we showed that this ligand-binding categorization is not only functionally but also clinically relevant. Patients belonging to the largest binding category had a poorer prognosis with a shorter time to first treatment than control patients. Our data suggest that CLL BCRs have a surprisingly confined structural diversity and that, if antigenic drive exists in CLL pathogenesis, the number of potential antigens may be much smaller than previously anticipated. Moreover, the peptides identified in this study may have potential as a targeting moiety for CLL-directed drug therapy.
Outcomes of Allogeneic Stem Cell Transplant in Patients with Myeloid Leukemias Over 65 Years of Age. Rationale for Aggressive Therapy with Curative Intent.
Authors: Giralt Sergio , Saliba Rima M , Rondon Gabriela , de Padua Silva Leandro , Alousi Amin M. , Popat Uday , De Lima Marco , Andersson Borje , Kebriae Partow , Anderlini Paolo , Hosing Chitra , Jones Roy , Shpall Elizabeth J. , Champlin Richard E. , Khouri Issa F. 
Published: April 2020

Abstract
Background: Improvements in supportive care and the use of reduced intensity conditioning regimens (RIC) have expanded the use of allogeneic stem cell transplantation (SCT) to older patients with myeloid leukemia (AML, MDS, CML or other myeloproliferative disorders). No large single or multi-institutional study looking at outcomes of patients over the age of 65 has been performed, and the results of allografting in septuagenarians (&gt;70 years of age) have not been reported.
Rationale: To explore the long-term outcomes of allogeneic transplant in patients with hematologic malignancies over the age of 65 and determine the impact of age and other prognostic factors in this subset of patients.
Patients and Methods: From 1/96 to 12/07 a total of 96 patients over the age of 65 underwent an allogeneic SCT for a myeloid leukemia. Patient, treatment characteristics and outcomes are summarized in the accompanying table.
Outcomes: For AML/MDS patients in remission between 65 and 70 years of age the OS at 2 years is 54% (95%CI:27–75) and 21% (95%CI:1–59) for patients 70 years or older (p=0.3); for AML/MDS patients not in remission OS @ 2 years was 21% (95%CI:9–36) for patients between 65 and 70 years of age and 0% for patients 70 yrs or older (p=0.06).
Conclusion: Allogeneic SCT can result in long term disease control in selected patients over the age of 65. Disease status at the time of transplant remains the most important prognostic factor for outcomes in this patient population. Patients over the age of 70 with AML/MDS in remission or with MPD can undergo allografting safely and achieve long term benefits, patients over 70 with refractory disease should be treated primarily on clinical trials aimed at improving outcomes in this patient population.
Less than 70 years of age 70 years of age or greater N 71 25 Median Age (range) 66 (65–69) 71 (70–76) AML/MDS 61 22 CML/MPD 10 3 Disease Stage @ SCT CR1/CR2/CP1 11/5/1 2/4/0 Other 54 19 Regimen Type Ablative 10 1 RIC 48 14 Non Ablative 13 10 % Matched Sibling Donor 60 60 % ATG in Conditioning 39 40 %OS @ 2 yrs (95%CI) 35 (24–46) 13 (3–30) p=0.08 %PFS @ 2 yrs (95%CI) 30 (19–42) 13 (3–30) %NRM @ 1 yr (95%CI) 24 (16–37) 44 (28–72) p=0.05 %aGVHD 2 or greater 28 (20–41) 35 (20–61) %cGVHD @ 2 yrs 35 (25–50) 26 (12–56) Figure Figure
Prognostic Significance of SALL4 Expression Levels in Paediatric Acute Myeloid Leukaemia (AML).
Authors: Ballerini Paola , Boelle Pierre-Yves , Deswarte Caroline , Auvrignon Anne , Couchy Gabrielle , Parker Judith Landman- , Robert Alain , Nelken Brigitte , Adam Mircea , Lapillonne Helene , Delabesse Eric , Perot Christine , Lai Jean Luc , Dastugue Nicole , Preudhomme Claude , Zucman-Rossi Jessica , Leverger Guy 
Published: April 2020

Abstract
Pediatric AML still represent an unfavourable disease resulting from the heterogeneous clonal expansion of malignant transformed haematopoietic stem or progenitor cell. The leukemia cell population is continuously replenish by rare, functionally distinct “leukaemia stem cells” (LSC) endowed with the capacity to self renew as well with the ability to generate clonogenic leukemic progenitors The AML-LSCs have been well documented and seem to behave like quiescent or slowly dividing hematopoietic stem cells. Therefore, LSC are considered less sensitive to treatments, which rather target actively dividing cells, and responsible for relapse. Recently, Y. Ma et al. suggested a major role of SALL4 gene both in stemness activity and leukemia transformation of normal hematopoietic stem cells. We sought to evaluate the expression of SALL4 gene in a panel of 88 pediatric AML, 60 Acute Lymphoblastic Leukemia (T and B ALL) and a few hematopoietic normal tissues. SALL4 expression was determined by quantitative RT-PCR in pre-treatment bone marrow samples (BM) (median blasts: 80%) and in normal tissues. SALL4 expression was much higher in AML compared to ALL (p&lt;0.0001) and normal tissue (p &lt; 0.0001). Values varied greatly among AML samples (range: 0 to 144; median 0.3). AML samples were dichotomized at SALL4’s median expression into“low” (n=44) or “high“(n=44) expressers. High expression was correlated to cytogenetic risk, as defined by MRC classes (p= 0.0008) but not to FAB categories, WBC, MLL rearrangements or FLT3, N RAS and NPM1 genotypes. Low expression was significant associated to t(8;21) translocation (P=0.02). SALL expression progressively increased from MRC1 class (low risk) to MRC3 (high risk) (p=0.002). High SALL4 patients had a shorter OS (OS: 46.8%±8% vs 74%±7%, p= 0.035) and a shorter EFS (EFS: 40% ± 8% vs 58% ±8%; P= 0.2) compared to low SALL4 expressers, although the latter association was less strong. As the highest values of SALL4 correlated with intermediate (MRC2) and high (MRC3) cytogenetic risk, we looked at fitting a model based upon the 4 quartiles of SALL4 expression. The upper quartile (values &gt; 16, n= 12) had the worst outcome compared to the three others. Once stratified on MRC groups, MRC2 patients in the upper SALL4 quartile had 3.2 times more risk of relapse (HR= 3.2, CI95%: 1.3–7.8, P=0.02) and 5.4 more risk to die (HR=5.4, CI95%: 1.8–7.6; P= 0.0005) than MRC2 patients in the three others quartiles. In conclusion, SALL4 expression level may define an important risk factor in AML, particularly among patients with cytogenetic intermediate risk.
Study of the Mechanisms by Which Angptl5 and IGFBP2 Support Ex Vivo Expansion of Human Cord Blood Hematopoietic Stem Cells.
Authors: Zheng Junke , Zhang Chengcheng 
Published: April 2020

Abstract
We previously showed that angiopoietin-like protein 5 (Angptl5) and IGF Binding Protein 2 (IGFBP2) support dramatic ex vivo expansion of human hematopoietic stem cells (HSCs). To understand the mechanisms of their action, here we studied the effects of Angptl5 and IGFBP2 on the surface phenotype, signaling activation, self-renewal, apoptosis, differentiation, and homing of human cord blood CD34+ cells. Using immunofluorescence staining, we showed that Angptl5 and IGFBP2 activate certain signaling pathways such as MAPK and Stat5 in human cord blood CD34+ cells. IGFBP2 and Angptl5 increased the expression of transcription factors HoxB4, Bmi-1, EZH2, and survivin, measured by intracellular staining flow cytometry analysis and real-time RT-PCR. IGFBP2 and Angptl5 also inhibit expression of certain transcription factors important for differentiation of myeloid, erythroid, and lymphoid lineages. To test whether IGFBP2 and Angptl5 affect the homing of HSCs, we cultured human cord blood CD34+ cells in serum-free medium supplemented with SCF, TPO, Flt3-L, IGFBP2 or Angptl5, and transplanted them into sublethally irradiated NOD/SCID mice intraveneously or intrafemorally. Both IGFBP2 and Angptl5 support ex vivo expansion of SRCs in intrafemorally injected mice, suggesting the expansion-stimulating effects elicited by both factors are not caused by modulation of HSC homing. Interestingly, when we used intrafemoral injection, we found that Angptl5 treated HSCs have enhanced engraftment in non-injected bone marrow. This suggests Angptl5 treated HSCs further facilitate the mobilization of HSCs in vivo. We conclude that IGFBP2 and Angptl5 support self-renewal and inhibit differentiation of human cord blood HSCs. Our data also suggest that a combination of expression of transcription factors important for self-renewal, survival, and differentiation of HSCs can be used as a “stemness index” that predicts the activity of cultured human HSCs.
Naïve B Cells Differentiate into Highly Activated Granzyme B-Secreting B Cells in Response to Interleukin 21 and B Cell Receptor Stimulation
Authors: Schwesinger Elisabeth , Hagn Magdalena , Simmet Thomas , Jahrsdoerfer Bernd 
Published: April 2020

Abstract
Human B cells have so far not been known to express the cytotoxic molecule granzyme B (GrB). Recently we found malignant B cells from patients with chronic lymphocytic leukemia, activated with interleukin 21 (IL-21), secrete high amounts of GrB. Here we demonstrate healthy human naïve B cells differentiate into GrB-secreting B cells in response to IL-21 and B cell receptor (BCR) cross-linking. After 72 hours up to 90% of viable B cells were differentiating. GrB-secreting B cells were more resistant to apoptosis than unstimulated B cells and non-viable B cells did not contain GrB, suggesting that the primary function of B-cell-derived GrB is not self-regulation. Differentiation was associated with a CD19+CD27-IgD-CD38-phenotype, increased dextran uptake and strong upregulation of molecules involved in cell adhesion (CD54), antigen-presentation (MHC class II) and co-stimulation (CD86). In summary we describe a novel differentiation pathway of naïve B cells into highly activated GrB-positive B cells in response to IL-21 and BCR stimulation. Our data indicate this differentiation serves potential interactions with target cells including antigen uptake and presentation, but not self-regulation. Our findings may have significant implications for understanding the role of B cells in immunity, and may open novel immunotherapeutic approaches.
IL-12 Stimulates Interferon-Gamma Mediated Inhibition of Tumor-Induced Regulatory T Cell Proliferation and Enhances Tumor Clearance
Authors: Cao Xuefang , Collins Lynne I. , Cai Sheng F. , Mayer Joshua C. , Walter Michael J. , Piwnica-Worms David , Schreiber Robert D. , Ley Timothy J. 
Published: April 2020

Abstract
We have recently demonstrated that regulatory T (Treg) cells in the tumor environment (but not in the peripheral lymphoid tissues) utilize granzyme B to suppress anti-tumor immunity (Immunity 2007 Oct; 27(4):635–46), which suggests that Treg cells may be subject to regulation by local factors during anti-tumor immune responses. In order to identify such factors, we have employed an unbiased approach. First, we performed cytokine profiling on the tumor ascites fluid (tumor environment) and plasma samples harvested from naïve and tumor-bearing mice by using rodent Multi-Analyte Profiles (MAPs) provided by Rules-Based Medicine (RBM). Second, we performed gene expression profiling on Treg cells purified from the tumor ascites, spleens of tumor-bearing mice, and spleens of naïve mice by using Affymetrix MOE430v2 arrays. By matching the profiles of local cytokines and their receptor expression on tumor-associated Treg cells, we identified candidate cytokines that may modulate Treg cell function. In addition, we developed an in vitro system to study Treg cell proliferation in the tumor setting. Co-culturing irradiated tumor cells with unfractionated splenocytes (but not purified Treg cells) induces significant expansion of CD4+Foxp3+ Treg cells (2–4 fold in 5 days), suggesting that accessory cells and/or factors produced by them are responsible for Treg expansion. Using this system, we tested candidate cytokines for potential effects on Treg proliferation. Remarkably, IL-12 treatment completely blocked Treg expansion in an IL-12 receptor-dependent fashion. However, absence of IL-12 receptor mRNA in Treg cells suggested an indirect mechanism for this effect. Notably, an Interferon-gamma (IFNg) neutralizing antibody partially abolishes this IL-12 effect, and IFNg treatment exhibits similar (but lesser) inhibition of Treg proliferation. Conversely, Treg cells in IFNg receptor-deficient cultures are partially resistant to IL-12 inhibition, but completely resistant to IFNg inhibition. Mechanistic analyses revealed that IFNg signaling directly causes cell cycle arrest in Treg cells. Furthermore, IL-12 treatment enhances tumor clearance in vivo, and is more efficacious than Treg cell depletion. These findings indicate that IL-12 can stimulate IFNg-mediated inhibition of Treg cell proliferation, which may partially account for the anti-tumor effect of this cytokine. This study provides definitive evidence that an IL-12/IFNg axis can function to inhibit Treg cell proliferation, and that Treg cells, as immune suppressors themselves, are subject to cytokine-mediated suppression during anti-tumor immune responses. Because antigen-based tumor vaccines have been found to activate Treg cells that can considerably dampen antitumor immunity, such Treg-inhibiting cytokines may have the potential to serve as an adjuvant for vaccine-based immunotherapy.
APRIL Provides Springtime for Antibody-Producing Plasma-Cell Lifetime
Authors: Huard Bertrand , Belnoue Elodie , Kee Thomas Mc , Matthes Thomas , Siegrist Claire-Anne , Roosnek Eddy 
Published: April 2020

Abstract
Antibody-producing plasma cells depend on their environment for survival, but the molecules involved in this process are still not well defined. Plasma cells are fully equipped to respond to a proliferation inducing ligand (APRIL) from the tumor necrosis factor (TNF) superfamily, by virtue of their constitutive expression of the B-cell maturation antigen (BCMA), as canonical receptor from the TNF receptor superfamily, and the heparan sulfate proteoglycan (HSPG), CD138, as co-receptor. Here, we report that APRIL promoted the in vitro survival of plasma cells by upregulating expression of several anti-apoptotic molecules, such as bcl-2, bcl-xL and mcl-1. We further observed an in situ localization for APRIL consistent with this pro-survival role, both in mucosa-associated lymphoid tissues (MALT) and the bone marrow. In upper MALT, the tonsillar epithelium produced APRIL. Upon infection, APRIL production increased considerably when APRIL-secreting neutrophils, recruited from the blood, infiltrated the crypt epithelium. HSPG retained secreted APRIL in the sub-epithelium of the infected zone to create APRIL-rich niches, wherein IgG-producing plasma cells accumulated. In lower MALT, neutrophils were the unique source of APRIL giving rise to similar niches for IgA-producing plasmocytes in villi of lamina propria. The requirement on an inflammatory reaction in niche establishment implies that plasma-cell survival in mucosa is associated to pathogen presence, and must be short as a consequence. We observed also APRIL in the bone marrow. In this latter organ, maturating granulocytes produced constitutively APRIL. Such constitutive expression of a plasma cell pro-survival explains, at least in part, why plasma-cell longevity in the bone marrow can be so long lasting. These in situ human observations were confirmed in vivo with APRIL-deficient mice.
Prolonged Inhibition of BCR Signaling and Suppression of B Cell Lymphoma through Irreversible Inhibition of Bruton’s Tyrosine Kinase
Authors: Evans Erica , Sheets Michael , Bernard Hugues , Martin Thia St. , Nacht Mariana , Tester Rich , Jewell Chuck , Mazdiyasni Hormoz , Petter Russell , Westlin William , Singh Juswinder 
Published: April 2020

Abstract
B-cell receptor (BCR) signaling is essential for normal B cell development and proliferation. In addition, functional BCR signaling contributes to the proliferation and survival of many B cell lymphomas through constitutive low level or tonic signaling. Disruption of this tonic signaling pathway results in cell death or decreased viability in many B cell lymphoma cells. Bruton’s tyrosine kinase (Btk) is a member of the Tec family of protein tyrosine kinases and plays a crucial role in the development and activation of B cells through association with the BCR signalosome. We have developed a novel, potent, irreversible inhibitor of Btk that selectively disrupts the BCR signaling pathway as measured by inhibition of both Btk Y223 autophosphorylation and phosphorylation of the Btk substrate PLCg2. AVL101 inhibits Btk but leaves upstream BCR kinase activity intact; both Syk phosphorylation at Y525/526 and transphosphorylation of Btk on residue Y551 are unaltered. By mass spectrometry, we have shown that AVL101 covalently modifies Btk specifically at Cys-481, and in cell-based assays, this irreversible binding leads to prolonged inhibition of Btk kinase activity. After removal of the compound, inhibition of Btk activity is maintained in cultured B cell lymphoma cells for &gt; 8 hours. This prolonged inhibition correlates with the half-life of the Btk protein, which we have found to be greater than 8 hours, irrespective of BCR activation state or modification by the inhibitor. We have demonstrated that AVL101 functionally inhibits BCR signaling in vitro and in vivo. In vitro, AVL101 inhibits BCR ligand-induced calcium flux as well as proliferation of the B cell lymphoma cell lines DOHH2 and WSU-DLCL2. In vivo, we have shown AVL101 is orally bioavailable and can inhibit Btk-dependent B cell function. Our data demonstrate that Btk is a valid therapeutic target for B cell lymphomas and other disorders dependent on BCR signaling. Furthermore, irreversible inhibition of Btk enables complete and prolonged inactivation of the target kinase, and suggests that clinically, a rapid and sustained therapeutic response may be possible using an orally available, irreversible Btk inhibitor.