bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prevention of Alloimmunization to Platelets and Cardiac Transplants by Mirasol‚ Pathogen Reduction Technology (PRT).
Authors: Asano Hiroshi , Lee Chih-Yuan , Baldwin William M. , Marschner Susanne , Goodrich Raymond 
Published: April 2020

Abstract
Functional WBCs in blood components may be responsible for a number of adverse transfusion effects, including alloimmunization and alloimmune platelet refractoriness. Attempts to reduce these undesired effects have used WBCs reduction filters and γ-irradiation. Previous studies have shown that exposure of platelet concentrates to riboflavin and light (Mirasol PRT treatment) causes irreparable modification of nucleic acids that results in inactivation of a wide range of pathogens as well as inhibition of the immunological responses mediated by the WBCs present in platelet concentrates. This study evaluated the ability of Mirasol PRT treatment to prevent alloimmunization and to modify the immune response to transplanted tissue in rats. Over a 10 week period, test animals (Lewis rats) received 8 transfusions of untreated or Mirasol treated platelet products containing leukocytes from DA rats. A third group of animals received saline injections. Antibody levels (IgG, IgM) in the recipient animals were monitored weekly. Animals were subsequently challenged with heart transplant under cyclosporine treatment to assess the effect of Mirasol PRT treatment on presensitization and transplant rejection. The IgM and IgG response in rats that received Mirasol PRT treated platelets was almost completely abolished compared to animals that received untreated platelets (see Figure below). In preliminary experiments, animals that mounted an IgG response also rejected the subsequent heart transplant. In summary, Mirasol PRT treatment prevented the development of an Ig response in transfused animals. This inhibition of an Ig response, in particular IgG, shows that Mirasol PRT treatment prevents alloimmunization. The inability to reject the heart transplant in the absence of an IgG response indicates that Mirasol PRT treatment may be effective in preventing alloimmune refractoriness to platelets and presensitization to transplants.
Figure Figure
Carbon Monoxide Atmosphere Allows Platelets To Retain Function and Hinder Pathogen Growth.
Authors: Shaklai Nurith , Amit Yonit , Tsemakhovitch Vladimir , Samuelov-Zubare Meirav , Shaklai Matityahu 
Published: April 2020

Abstract
Platelets are the sole blood fraction which is currently preserved at room temperature and thus exposed to microorganisms, specifically bacterial, growth. Bacterial contamination in platelet concentrate (PC), in a range of up to 0.4%, is the major cause of morbidity and mortality in transfusion medicine. To extend the current limited shelf life of 5 days for platelets, fast screening methods have been developed. Alternatively, methods for inactivation of bacterial growth by DNA crosslinking are provided. The latter include treatment by psoralen or photodynamic inactivation such as riboflavin activated by irradiation. The drawback of these efficient methods which relates to large investment and unknown future side effects, calls for alternative preservation methods. In the current study we demonstrate an option to store PC under sealed anaerobic, carbon monoxide atmosphere, in which neutral pH is kept by bicarbonate (Cob). The procedure is simple and cost effective.
Freshly isolated platelets (PC) were prepared by the Israel Central Blood Bank and stored in plastic flasks either allowing air transfer (control) or in gas non-transparent, Cob, at 22°C. Growth of inoculated bacteria in Cob stored PC was arrested immediately or after one log. Integrity of Cob platelets was better than control as assessed by leak of lactic dehydrogenase (LDH). Leak of LDH was lower as compared to control cells. P-selectin exposure on long term preserved platelets (days 6–9) was lower in Cob preserved platelets as compared to identical control PC. Phosophatydil serine (PS) measurement using flow cytometry indicated a large exposure in Cob platelets stored longer than 4 days, concomitant with consumption of all glucose, the energy source for anaerobic metabolism, in plasma. However, introduction of air resulted in a reversible reduction of the exposed PS. To better mimic in vivo viability of stored platelets, additional experiments were carried out using reconstituted blood (R-blood) prepared as follows: Platelets were removed from freshly drawn blood and stored PC were added to yield a concentration of ~ 350,000/μl. Aggregability of control and Cob R-blood were compared using a “paleletworks” kit (Helena company). Aggregability of stored PC was reduced with time. Nevertheless, aggregability of Cob platelets stored in R-blood was always significantly higher than its twin, air stored, sample. Adhesion of the stored platelets was estimated using Cone and Plate Analyzer (Diamed). No differences were found, within error, between air and Cob stored R-blood. In vivo survival of the stored platelets was assessed using a previously described rabbit model. Survival time declined with prolonged preservation in both control and COb stored platelets. No differences within error were observed between control and COb preserved platelets. These results indicate the option to use COb method for storage of platelets in a viable, pathogen reduced manner.
Generation of Kinins during Preparation and Storage of Leukoreduced Platelet Concentrates.
Authors: Moreau Marie Eve , Thibault Louis , Désormeaux Anik , Marceau François , de Grandmont Marie-Joëlle , Lemieux Réal , Robillard Pierre , Rivard Georges E. , Lepage Yves , Adam Albert 
Published: April 2020

Abstract
BACKGROUND. Severe hypotensive reactions can occur following transfusion of blood components, particularly with platelets concentrates (PCs) leukoreduced with negatively- charged filters. Bradykinin (BK)-related peptides were proposed as a possible cause of this side-effect. This study evaluated the effects of leukoreduction and storage conditions on the levels of two kinins (BK and des-Arg9-BK) in PCs.
METHODS. Whole blood donations (n=35) were processed using current PRP (platelet-rich plasma) procedure to prepare leukoreduced and unfiltered components by Leukotrap® RC-PL Whole Blood Collection, Filtration and Storage System. PCs and plasma were stored for 7 days at 20–24°C with agitation. Levels of BK and des-Arg9-BK were measured by specific enzyme immunoassays and HPLC at day 0, 2, 5 and 7 of storage. Mechanisms potentially responsible for accumulation of BK and des-Arg9-BK were studied.
RESULTS. On day 0, kinins were measured in significantly higher concentrations in leukoreduced (BK: 101 ± 157 pg/mL; des-Arg9-BK: 194 ± 191 pg/mL) vs unfiltered PCs (BK: 71 ± 121 pg/mL; des-Arg9-BK: 98 ± 114 pg/mL). During storage, both kinins peaked on day 5, with concentrations higher than 1 ng/mL in 22% of leukoreduced as well as unfiltered PCs. Physicochemical and pharmacological characterization of immunoreactive kinins confirmed their nature. In vitro activation of the contact system of the corresponding platelet-poor plasma (PPP) showed that a high kinin concentration on day 5 of the storage corresponded to a low kinin-forming capacity of plasma. On day 7, BK was no longer elevated presumably due to its degradation and the depletion of kinin-forming capacity of the plasma in stored PCs. The activity of metallopeptidases that metabolize BK-related peptides in plasma from PCs were at levels similar to those recorded in the plasma of a normal reference population and were unaffected by storage.
CONCLUSIONS. Our results indicate that filtration and storage conditions of PCs contribute to generation of pharmacologically relevant bradykinin levels that might pose a risk in susceptible patients. The clinical relevance of such high concentrations of kinins in PCs remains to be established but could potentially be significant especially in patients treated with angiotensin I-converting enzyme-inhibitors that affect the pathway of BK degradation.
Signaling Pathways in HIT Immune Complex Stimulation of Monocyte Tissue Factor.
Authors: McKenzie Steven E. , Cassel Diana L. , Casasanto Peter , Taylor Scott M. , Reilly Michael P. 
Published: April 2020

Abstract
In heparin-induced thrombocytopenia (HIT), platelet-fibrin thrombi form in vivo due to generation of thrombin initiated by intravascular tissue factor (TF). Stimulation of monocytic cells in vitro by the HIT immune complex (IC), consisting of heparin/PF4 complexes and IgG anti-hep/PF4 antibodies, triggers TF expression. The HIT IC binds to Fcγ receptors on monocytic cells to initiate a signal cascade which results in new TF transcription. Though much is known about monocyte TF transcription as a consequence of LPS stimulation of TLR4, the mechanism by which HIT IC engagement of FcγR leads to TF transcription is unknown. Transcription of pro-inflammatory and anti-inflammatory cytokines as a consequence of IC engagement of FcγRs on monocytes has been reported to involve the ras/Erk and/or PI3K/Akt pathways downstream of syk. We tested the hypothesis that HIT IC- FcγR engagement signals via a PI3K/Akt pathway to trigger TF transcription. We created a model HIT IC consisting of an optimal ratio of heparin and recombinant human PF4, bound by well-characterized monoclonal anti-hep/hPF4 antibody KKO. Using human monocytic cell line THP-1, we observed that the HIT IC induction of new TF mRNA, assessed by qRT-PCR after treatment for 2 h at 37°C, was reduced approximately 80% by pretreatment of the cells with PI3K inhibitor wortmannin (100 nM; n = 3, p &lt; 0.05). In addition, the same effect was observed with another IC, heat-aggregated human IgG, namely 80% inhibition of stimulated TF expression by wortmannin (pretreatment with 100 nM, 37°C, 30 min, n = 4, p&lt; 0.05). Of note, the LPS-mediated increase in TF expression was enhanced over 2-fold (1 ug/ml, 2 h, p &lt;0.05) by the same wortmannin pretreatment, in direct contrast to the result with IC stimulation. In preliminary studies with Akt inhibitor SH5, we have observed ~80% inhibition of IC-stimulated TF expression. We have verified the effects of PI3K inhibition of IC-stimulation of TF (75–80% inhibition by wortmannin pretreatment) by using primary peritoneal macrophages derived from FcγRIIa-transgenic mice, which express a similar FcγR pattern as human cells and our HIT mouse model. Immunoblot analysis of phospho-Akt using anti-Ser473 Akt antibody(generously provided by Donna Woulfe, PhD, Thomas Jefferson University) verified the phosphorylation of Akt by HIT IC treatment and marked reduction when PI3K was inhibited. In summary, HIT IC stimulation of monocytic cell TF involves a PI3K/Akt pathway in a way clearly distinct from LPS-stimulated TF expression. Further studies are in progress to elucidate the upstream activators and downstream effectors, the role of other signaling pathways and the identity of the responsible transcription factor complexes.
Comparative Proteome Analysis To Study Novel Markers of the Blood Platelet Lesion.
Authors: Schubert Peter , Thon Jonathan N. , Duguay Marie , Serrano Katherine , Devine Dana V. , Kast Juergen 
Published: April 2020

Abstract
Platelet transfusion is a very common live-saving medical procedure for patients with platelet-deficient diseases like leukemia. In contrast to other blood components, the availability of platelets is restricted since they have a limited shelf-life of 5 days for transfusion purposes. This is due to storage-related deterioration in product quality resulting in the clearance from circulation. To overcome this problem, it is important to understand the molecular mechanisms leading to blood platelet lesion during storage. We were using two different proteomic approaches combined with functional biochemistry to investigate time-dependent changes in the blood platelet proteome. One type of analysis consisted of the separation of the platelet proteome at two different time points of storage, day 1 and day 8, using 2-dimensional (2D) gel electrophoresis for qualitative and DIGE technology for quantitative analysis. The identification of proteins changing in spot intensity was carried out by liquid chromatography and tandem mass spectrometry. The second method was based on stable isotope labeling with ITRAQ/ICAT reagents in combination with protease treatment, equivalent mixing, separation of the resulting peptides and quantitative analysis by mass spectrometry. Taken together, for the 2D/DIGE approach we analyzed 977 spots corresponding to 103 different proteins and for the ITRAQ approach 1428 peptides corresponding to 355 proteins, resulting in 37 proteins significantly changing both quantitatively due to protein synthesis or degradation and qualitatively due to post-translational modification and enzymatic activity. The high degree of correlation between the two approaches validates the experimental set-up and confirmed the requirement for complementary tools to enhance proteome coverage. Among others, increased amounts of integrins and other proteins known to form receptor signaling complexes with these integrins as well as proteins observed in platelet activation were detected. This proves, for the first time, that there is an apparent link between blood platelet storage lesion and cell signaling.
Production of Megakaryocytes and Platelets from Common Marmoset (Callithrix jacchus) ES Cells by Constitutive Expression of tal1/scl Gene.
Authors: Kurita Ryo , Yokoo Tomoko , Sasaki Erika , Dong Yan , Suehiro Youko , Tanioka Yoshikuni , Soda Yasushi , Komatsu Norio , Tani Kenzaburo 
Published: April 2020

Abstract
Since the successful establishment of human embryonic stem (ES) cell lines in 1998, transplantation of the differentiated ES cells to specific organ has been expected to cure its defective function. For the realistic medicine, the preclinical studies using animal model systems including non-human primates are essential. We have already demonstrated that 1) non-human primates of common marmosets (CM) are suitable for the laboratory animal models for preclinical studies of hematopoietic stem cell therapy and 2) tal1/scl gene transduction using a lentiviral vector is a very useful tool for the efficient hematopoietic cell differentiation from CM ES cells. In this study, we especially focused on the differentiation of CM ES cells to megakaryocytes and platelets in stroma cell-free conditions in order to investigate the feasibility of future new transfusion therapy. Firstly, we established CM ES cell line, which expressed tal1/scl gene constitutively (CM ES-tal1/scl). This ES cell line exhibited undifferentiated morphology and expressed stage-specific embryonic antigen (SSEA)-3 and SSEA-4, while SSEA-1 was not detected. The induction of hematopoietic cells from CM ES-tal1/scl was more efficient than that of original ES cell line. Next, by using this cell line, we planned to produce megakaryocytes and platelets efficiently. During semi-long culture (&lt; 1 month) in the presence of thrombopoietin (10–100 ng/ml), we obtained some proplatelet-like structures, which showed CD41 expression by immunohistostaining, in the adherent cells. Furthermore, 2–4% of CD41 positive platelet-like fraction was observed in the culture supernatant by flow cytometry, although the induction efficiency was low. Now, we examine the efficient culture conditions including additional gene transduction such as gata1, runx1, and NF-E2 genes.
Prognostic Factors and Treatment Outcome in Lymphocyte Predominant and Classical Hodgkin’s Lymphoma: A Comprehensive Analysis of the German Hodgkin Study Group.
Authors: Nogova Lucia , Reineke Thorsten , Brillant Corinne , Ruediger Thomas , Mueller-Hermelink Hans K. , Bredenfeld Henning , Josting Andreas , Mueller Rolf P. , Diehl Volker , Engert Andreas 
Published: April 2020

Abstract
Introduction: Lymphocyte predominant Hodgkin lymphoma (LPHL) differs in histological and clinical presentation from classical Hodgkin lymphoma (cHL). Treatment of LPHL patients using standard approaches leads to complete remission (CR) in more than 95% of patients. However, differences in terms of relapse rates, overall survival (OS) and freedom from treatment failure (FFTF) between LPHL and cHL patients were suggested by a recent intergroup analysis. To obtain a more comprehensive picture, we reviewed all LPHL-cases registered in the GHSG database comparing patient characteristics and treatment outcome with cHL patients.
Patients and methods: We retrospectively analyzed 8298 HL patients treated within the GHSG trials (HD4 to HD12). 394 patients had LPHL and 7904 cHL. From 394 LPHL patients, 63% were in early favorable stage, 16% in early unfavorable and 21% in advanced stage of disease. Of the 7904 cHL patients analyzed, 22% were in early favorable, 39% in early unfavorable and 39% in advanced stages. 9% of LPHL patients had B symptoms compared to 40% in cHL patients.
Results: 91% LPHL vs. 86% cHL patients in early favorable stages, 86% vs. 83% in early unfavorable and 79% vs. 75% in advanced stages reached CR/CRu. 0.3% LPHL patients developed progressive disease (PD) compared to 3.7% cHL patients. The relapse rate of LPHL patients was very similar to cHL (8.1% vs. 7.9%). There were 2.5% secondary malignancies in LPHL and 3.7% in cHL patients. 4.3% LPHL patients and 8.8% cHL patients died. The FFTF rates for LPHL and cHL patients at a median observation of 41 or 48 months were 88% and 82% (p=0.0093), respectively. The OS for LPHL and cHL patients was 96% and 92%, respectively (p=0.0166). The analysis between LPHL stages showed significant differences in FFTF (p=0.0239). According to a multiple Cox-regression analysis, advanced stage (p=0.0089) and lymphocytes &lt; 8% of white cell count was shown as negative prognostic factors for FFTF and age ≥ 45 years (p=0.008) as negative factor for OS in LPHL patients. Hb value &lt; 10.5 g/dl was shown as negative factor for both, FFTF and OS (p=0.0125, p=0.0002).
Conclusion: This is the largest analysis comparing LPHL and cHL patients. We found differences in FFTF and OS rates between both groups and differences in FFTF between LPHL stages. New treatment protocols for LPHL patients with reduced intensity schedules are to be discussed.
Small Populations of PNH-Type Cells in Aplastic Anemia Patients Are Derived from PIG-A Mutant Stem Cell Clones without Proliferative Advantage.
Authors: Mochizuki Kanako , Sugimori Chiharu , Feng Xingmin , Lu Xuzhang , Reed Gudrun H. , Wittwer Carl T. , Nakao Shinji 
Published: April 2020

Abstract
Several studies revealed that a small number of glycosylphosphatidylinositol anchored protein-deficient cells are detectable in peripheral blood of healthy individuals but these PNH-type cells do not persist for a long time because they are originated from committed progenitor cells rather than primitive stem cells with PIG-A gene mutations. We have studied more than 700 patients with AA for the presence of CD55-CD59- granulocytes and red blood cells using highly sensitive flow cytometry and detected 0.003% or more PNH-type cells in about 50% of patients. In patients whose proportions of PNH-type are very low, the appearance of PNH-type cells may also be transient because they are not derived from true PIG-A mutant stem cell clones. In an attempt to characterize hematopoietic clones from which small populations of PNH-type cells are originated, we studied changes in the proportion of PNH-type granulocytes, clinical findings, and PIG-A mutations over 3–7 years on 52 AA patients (18 males and 33 females). The initial examination revealed less than 0.1% (0–0.075%) PNH-type granulocytes in 21 patients (Group A) and more than 0.1% (0.101–36%) PNH-type granulocytes in 31 patients (Group B). In three (14%) patients of Group A, PNH-type granulocytes became undetectable 2.9, 1.3 and 1.6 years after the initial examination. 0.007 % granulocytes became detectable 2.5 years after the first examination which produced a negative result in one patient. Among the other 17 (81%) patients of Group A, proportions of PNH-type granulocytes remained stable at 0.03–0.41% over 3–6 years. By contrast, 5 (16%) patients of Group B showed an apparent increase in the proportion of PNH-type cells (from 1.46%, 1.63%, 3.31%, 23%, and 36% to 79%, 21%, 83%, 55%, and 78%, respectively) 2 to 4 years after the initial examination. Four of the five developed clinical signs of hemolysis. The proportion of PNH-type cells in Group B patients remained stable in 33 (63%) patients and declined in 12 (23%) patients. When we sorted a small (0.04%) population of PNH-type granulocytes from a patients of Group A and analyzed PIG-A gene, only one point mutation at position 479, C to T was revealed in the exon 2. The finding that the proportion of PNH-type cells remained stable over 3 years in most Group A patients suggests that very low proportions of PNH-type cells are derived from primitive hematopoietic stem cell clones with PIG-A mutation. Among AA patients displaying small populations of PNH-type cells, only those whose proportion of PNH-type cells are more than 1% may be at a high risk of developing hemolytic PNH.