bluuebunny/crossref_metadata_2025 huggingface dataset:
The PAI-I Gene 4G/5G Polymorphism and Central Nervous System Bleeding In Factor XIII Deficiency
Authors: Naderi Majid , Dorgalaleh Akbar , Alizadeh Shaban , Tabibian Shadi , Taregh Bamedi , Karimi Mehran
Published: October 2019

Background

FXIII deficiency is one of the rare bleeding disorder (RBD) that has a highest incidence in Sistan and Baluchistan province around the world. This disorder represents with different clinical manifestations ranging from mild to severe bleeding tendency including CNS bleeding. The aim of this study is to evaluate the role of PAI-14G/5Gpolymorphism in central nervous bleeding (intra and extracranial hemorrhage) system in factor XIII deficiency.

Methods

In this case control study was studied 32 FXIII deficient patients with CNS bleeding and also 32 patients with factor XIII deficiency without history of CNS bleeding as control group. Initially both groups were evaluated for the previously reported polymorphism of factor XIII (Trp187Argpolymorphism) in order to confirm their disorder. Then all patients were assessed for PAI-14G/5G polymorphism. Eventually obtained data was analyzed by SPSS software.

Results

The result of this study revealed that all study patients were homozygote for Trp187Arg polymorphism. We also found that the equal numbers of patients (4 individuals) in case and control groups were heterozygote for PAI-14G/5G polymorphism and none of patients were homozygote for this polymorphism. All heterozygote patients had intracranial hemorrhage and patients with extracranial hemorrhage had no mutation of PAI-14G/5G. Intraparenchymal was the most common site of hemorrhage and was observed in 26 patients (92.8%).We also observed subdural and epidural hemorrhage in two patients (7.1%).Anatomic regions in patients with intraparenchymal hemorrhage, were temporal in nine (32.2%), occipital in eight (28.6%), diffused intraparenchymal hemorrhage in seven (25%), tempro-occipital in two (7.1%) and subdural with temporal in two (7.1%) patients. Conclusion: It seems that PAI-14G/5G polymorphism did not any effect on occurrence of intra and extracranial hemorrhage in patients with factor XIII deficiency.

Disclosures:

No relevant conflicts of interest to declare.
Is a Standardized Preoperative Questionnaire a Good Tool To Detected Coagulation Disorders In Children
Authors: Halimeh Susan , Rott Hannelore , Kappert Guenther , Siebert Manuela
Published: October 2019

Introduction

In our study 144 children were send to our coagulation centre with a positive anamnesis (such as haematomas or nose bleeding’s) a positive family anamnesis (p.e. Mother with Menorrhagie) or a prolonged aPTT during a standardized preoperative examination.

Samples and Methods

We analyzed samples of 144 children by conduction the following tests: Blood count, VWF:RCo, VWF:Ag, VWF:CB, Fibrinogen (Clauss), activities of FII, FV, FVII, FVIII (clotting and chromogenic), FIX, FX, FXI, FXII, FXIII.

Results

In 107 of 144 children (74.3%) a bleeding disorder could be detected. In those with a bleeding disorder the distribution was as followed: 23.6% had a von Willebrand disease, 27.8% had a prolonged bleeding time and 5.6% a factor XIII-deficiency. The remaining 43% hat other bleeding.

disorders (e.g. FVIII-deficiency, FVII-deficiency and other mild factor deficiencies).

Discussion

A standardized preoperative questionnaire can be useful in clinical practice. In our study 74.3% children with one or more positive evidence in the anamnesis suffer from a bleeding disorder. It is specifically noticeable that we found in 68% of the children which mother has a menorrhagia a bleeding disorder. In 31.8% of the children we found a von Willebrand disease.

In our more coagulation disorders could be detected if a standardized preoperative questionnaire would be used and if we pay more attention to children with would a mothers with menorrhagia.

Conclusions

Children from mothers with menorrhagia suffer more frequently from a bleeding disorder. In our patients in 75% of the children with a mother with menorrhagia a bleeding disorder was found.

To avoid an unexpected bleeding during a planned surgery or a postoperative bleeding a standardized preoperative questionnaire should be performed.

Disclosures:

Halimeh: Octapharma AG: Investigator Other, Research Funding.
Dose Adjustment Of Low Molecular Weight Heparins (LMWH) Improves Pregnancy Outcome In Thrombophilic Women
Authors: Catania Gioacchino , Pini Massimo , Laura Contino , Flavia Salvi
Published: October 2019

Introduction

Acquired and inherited thrombophilias are associated with unfavourable pregnancy outcome. Low-molecular-weight heparin (LMWH) has demonstrated utility in the prevention and treatment of thrombosis during the pregnancy. There is no consensus on the dose of LMWH for prophylaxis, between fixed dose and “adjusted” dose according to anti-Xa levels.

We report our experience the management of heparin-therapy during pregnancy in thrombophilic women.

Methods

We performed a retrospective analysis of patients with high risk of venous thromboembolism (VTE) and obstetric complications during pregnancy. Table 1 shows the risk factors of VTE in pregnancy. The obstetric complications considered were: preeclampsia, fetal growth restriction, fetal death and recurrent miscarriages. All patients were prescribed enoxaparin 70-100 IU /Kg SC once daily. To determine the dose of LMWH we evaluated levels of anti-factor Xa (chromogenic test) and the utero-placental circulation with color Doppler ultrasound. Dose adjustment was performed if the activity of factor Xa was suboptimal (prophylaxis range > 0.4IU/ml and < 0.8 IU/ml anti-Xa value) or were detected alteration in the utero-placental circulation.

Outcome Measures

Time of delivery, birth weights and Apgar-index.

Results

70 pregnancies for 68 women were recruited between January 2008 and December 2012. The median age of patients was 35 years (range 25- 43years) and 7 (10%) were over 40. Twenty-four patients had a previous VTE and thirty-six had an obstetric complications.

No one patients reported thrombotic and/or hemorrhagic complications during heparin treatment. In 97 % of cases the time of delivery occurred after 36th weeks of pregnancy, with a birth weight greater than 2600 grams and Apgar score index higher than 7.

The dose of LMWH had to be adjusted at least once during the course of the pregnancy and the mean daily dose was increased from 4.000UI to 8.000UI between the 12th and 32th week of gestation.

Conclusion

In pregnancy LMWH thromboprophylaxis enables the modulation of systemic haemostatic parameters by the inhibition of factor Xa and by increasing TFPI levels. In the literature-in some high risk pregnancy- the weight-based dosing of LMWH could seem to fail achieving a prophylactic anticoagulation.

In our experience adjusted doses prevent unfavourable events and improve fetal growth.

°Carriage of defects of antithrombin, protein C or S, factor V Leiden, G20210A prothrombin mutation, antiphospholipid syndrom

Disclosures:

No relevant conflicts of interest to declare.
Venous Thromboembolism (VTE) In Patients With Pancreatic Cancer
Authors: Kim Kyoung Ha , Yoon Seug Yun , Yoon Jina , Kim Han Jo , Kim Se Hyung , Kim Hyun Jung , Lee Sang-Cheol , Bae Sang Byung , Kim Chan-Kyu , Lee Namsu , Park Sung Kyu , Won Jong-Ho , Hong Dae Sik , Park Hee Sook
Published: October 2019

Background

Venous thromboembolism (VTE) is a critical complication of malignant disease. Pancreatic cancer is one of the cancers most commonly associated VTE. In general, the VTE incidence rate of Asians is lower than that of Caucasians. In 2007, a Korean study reported that only four cases of VTE (5.3%) occurred in Seventy five patients with advanced pancreatic adenocarcinoma. We evaluated VTE incidence in pancreatic cancer and characteristics of pancreatic cancer patients with VTE.

(We found out that VTE incidence rate among Asians was not lower, and the event of VTE was poor prognosis.)

Method

We retrospectively reviewed the medical records of patients with histopathologically proven pancreatic cancer from January 2006 to December 2012 at Soonchunhyang university hospital. We detected VTE through CT (chest CT, pulmonary embolism CT) and low extremity ultrasoundgraphy.

Results

Five hundred and fourteen patients with pancreatic adenocarcinoma were enrolled. (M: F, 300:214, localized: locally advanced: metastatic=31:230:253, mean age: 66.7 years). Ninety six of 514 patients (18.6%, symptomatic: aymptomatic=38:58, PE: DVT: PE+DVT: visceral thrombosis=20:19:19:38) were diagnosed as VTE. At the time of DVT diagnosis, cancer status of 50 patients cancer was progression, and that of 15 was stable. Thirty one patients were diagnosed with the pancreatic cancer and VTE, at the same time. They all had metastatic lesions. Fifty VTE patients were treated with antithrombotic therapy. Ninety three of 96 patients died, and three of them have probability that cause of death was VTE. The others died of pancreatic cancer progression. From pancreatic cancer diagnosis to VTE diagnosis, the period is 1.7month. (95%CI 1.1-2.3 month). Median overall survival (OS) was not significantly different between pancreatic cancer with VTE or without VTE. OS was significantly longer VTE patients after pancreatic cancer diagnosis than VTE patients with pancreatic cancer at the same time (10.73m vs. 1.7, p=0.00).

Conclusion

The incidence of VTE (18.6%) in Soonchunhyang university hospital with pancreatic cancer was not lower than that in western groups.

Disclosures:

No relevant conflicts of interest to declare.
Elevated Factor VIII Activity In Patients With Hypercoagulability Syndrome
Authors: Gonzalez F. , Paredes Hanrry J
Published: October 2019

Patients with hypercoagulability syndrome can have a wide variety of risk factors that predispose them to develop a thrombotic event. Factor VIII increased levels has been reported as one of these. In this retrospective study we report the frequency of increased levels of factor VIII activity found in patients referred for hypercoagulability assessment to our reference center.

Material and methods

Review of clinical and laboratory database of patients referred for hypercoagulability assessment. Results are presented as percentages.

Results

Of 323 patients with hypercoagulability syndrome, 98 (30.3%) had increased levels of Factor VIII activity, male-female ratio 1:1.8, mean age 49.8 ± 15 y-o. Sixty (61.2%) patients had a venous thrombotic event and 73.3% of them had recurrence. Ten (10.2%) had an arterial thrombotic event and 23 a combined arterial and venous thrombosis with recurrent episodes of 70.0 and 82.6% respectively. Five patients had no clotting events. Thrombosis in unusual sites was found in 22 patients.

Conclusion

Increased levels of Factor VIII activity are found in 30.3 % of patients with hypercoagulability syndromes, almost two thirds develop a venous thrombotic event and recurrences occur in 75.3%.

Disclosures:

No relevant conflicts of interest to declare.
Thrombosis and Acute Myeloid Leukemia In Morocco: Management, Difficulties and Adapted Guidelines
Authors: Anoun Soumaya , Lamchahab Mouna , Moussali Nadia , Oukkache Bouchra , Benchekroun Said , Quessar Asmaa
Published: October 2019

Background

Thromboembolism is a well-known fatal complication of malignancies. Acute lymphoid leukaemia and non-Hodgkin lymphomas are the most common haematological malignancies associated to thrombosis. The management of thrombosis involve anticoagulant treatment which is difficult to administrate in thrombocytopenic patients especially in conditions where supportive care by platelet transfusion is not well developed, and the cost of low molecular weight heparin is high comparing to population monthly income.

Our aim is to define the incidence of thrombosis in AML patients, to relate difficulties of anticoagulant management and to develop adapted guidelines for the use of anticoagulation in developing countries.

Patients and methods

We conducted a retrospective study on 1000 patients with newly diagnosed AML admitted to our institution from January 2003 to June 2013. Diagnosis of AML was essentially based on French–American–British (FAB) guidelines. Moreover, diagnosis of acute promyelocytic leukemia (APL) was confirmed by karyotype. Deep venous thrombosis (DVT) was confirmed by Doppler ultrasonography and cerebral thrombosis (CT) was confirmed by angio cerebral MRI. The thrombosis scoring was according to Khorana and well scores. Patients started chemotherapy induction treatment as soon as diagnosed and anticoagulation treatment was initiated when the patient was stable. Platelet transfusions were given when platelet count became less than 10 G/L, or 20G/ L in the case of fever or bleeding. Were included in the study all patients with inaugural thrombosis at diagnosis. And were excluded all secondary thrombosis (catheter related thrombosis. etc.)

Results

Only five cases of inaugural thrombosis were collected in our series. The incidence of thrombosis is 0.5/ 100 cases /year. Thrombosis is well misdiagnosed in our conditions. The mean age was 40 years (range 28-48 years). Sex ratio showed male predominance. The mean platelet count (Plt) at diagnosis was at 36.6 G/l (range 4- 98 G/l). Hyperleucocytosis was seen in two cases with a mean of white blood count (WBC) of 21.6 G/l (range 1- 82 G/l). One patient was diagnosed as APL. Wells score was less than three in all patients. Khorana score classed all patients in low or intermediate risk. Four patients had DVT and one patient complained from CT. The time from thrombosis to anticoagulant treatment ranged from 1 day to 3 days. Two patients were treated by LMWH and died (one from pulmonary embolism). The three others were treated by unfractionated heparin (UNH) and achieved complete remission (CR). (Table).

Conclusion

UNH is the best adapted treatment of thrombosis in developing countries AML patients. Supportive care by platelet transfusion twice a day stays the best way to well manage AML and anticoagulant complications by keeping platelet count more than 50G/l.

Disclosures:

No relevant conflicts of interest to declare.
Thromboelastographic Follow-Up Of Prophylactic Thrombocyte Transfusion
Authors: Sahin Deniz Goren , Akay Olga M. , Karagulle Mustafa , Gunduz Eren , Gulbas Zafer
Published: October 2019

Introduction

Prophylactic thrombocyte transfusion is being used to reduce increased bleeding risk after chemotherapy treatment for leukemia or malignancy. This transfusion is frequently applied when thrombocyte count is below <10.000/uL or between 10.000 and 20.000/uL. However, it was shown that thrombocyte count alone is not enough for determining bleeding risk. Moreover, given the fact that thrombocyte transfusions have inherent risks and economic burden, new laboratory approaches such as thromboelastography can be considered to determine bleeding risk in these patients. Thromboelastography is a new alternative method to conventional coagulation tests, which gives information about hemostatic system by evaluating clot’s visco-elastic and mechanical features. The aim of our study to establish a transfusion algorithm by thromboelastographic follow-up of prophylactic thrombocyte transfusion.

Methods

Eighty patients who have been diagnosed as acute leukemia were randomized into 4 groups. Six units random thrombocyte was given to the first group, three units random thrombocyte was given to the second group, one unit apheresis was given to the third group, and ½ unit apheresis was given to the fourth group. Before and 15 minutes after transfusion, peripheral blood was taken and CBC and rotation thromboelastograpy (ROTEM) was performed by standard device (Pentapharm GmbH, Munich, Germany). Clotting time (CT), clot formation time (CFT), and maximum clot firmness (MCF) were evaluated by 2 methods, in-TEM and ex-TEM. Patients were followed up during study by using clinical bleeding signs based on WHO bleeding grade. Patients who used medications that can affect thrombocyte functions within the last 14 days and patients who have systemic disorders (renal, hepatic, endocrinological) or hemostatic disorders were not included in this study. Variance analysis was used in order to find out statistical differences. P<0.05 was considered statistically significant.

Results

When platelet counts and ROTEM results were analyzed for each parameter before platelet transfusion, there were no statistically significant differences among groups. We analyzed the differences of platelet counts and thromboelastographic parameters before and after prophylactic platelet transfusion and we didn’t see any statistically significant differences between groups. Clinical bleeding signs were not correlated with platelet count in any groups.

Conclusion

Six units random, three units random, complete apheresis or half apheresis prophylactic platelet transfusion does not cause any significant changes in platelet count, ROTEM parameters and clinical bleeding signs. Therefore, low dose platelet transfusion can be considered because of its lower economic burden. Moreover, further studies are needed to evaluate the potential of ROTEM as an independent factor for transfusion indication.

Disclosures:

No relevant conflicts of interest to declare.
Targeted correction Of RUNX1 Mutation In The FPD Patient-Specific Induced Pluripotent Stem Cells Restores Megakaryocytic Differentiation
Authors: Kwon Erika Mijin , Connelly Jon P , Gao Yongxing , Horwitz Marshall , Cheng Linzhao , Liu Pu Paul
Published: October 2019

Familial platelet disorder with propensity to acute myeloid leukemia (FPD/AML) is a rare autosomal dominant disease caused by RUNX1 mutations. RUNX1 encodes a transcription factor, which is frequently mutated in leukemias. It is also essential in early hematopoiesis and megakaryocytic differentiation. FPD patients have a mild to moderate bleeding disorder, thrombocytopenia, and over 35% of patients will develop AML during their lifetime. Currently there are no suitable animal models for the disease, making it necessary to develop alternative approaches for research studies.

To develop an in vitro model of FPD, we established induced pluripotent stem cell (iPSC) lines using episomal, non-integrating vectors from skin fibroblasts from a family of FPD patients harboring a nonsense mutation in the C-terminal region of the RUNX1 (Y260X). The derived iPSC lines showed typical characteristics of pluripotency such as teratoma formation and expressions of pluripotency markers (Oct4, Sox2, Nanog, and Tra-1-81). In order to correct the mutation in the patient-specific iPSCs by homologous recombination, we designed a pair of RUNX1 zinc finger nucleases (ZFNs) and a targeting vector. We then performed ZFN-mediated gene targeting in one of the FPD iPSC lines and confirmed correction of the mutant RUNX1 allele in at least two iPSC clones by Southern, FISH and sequence analyses. RUNX1 mRNA expression analysis of the FPD iPSC line and the corrected iPSC lines showed expression of only wildtype RUNX1 transcripts in the corrected iPSC lines, but not in the uncorrected lines. Furthermore, we directed hematopoietic differentiation of the FPD iPSCs and the corrected iPSC lines using the spin embryoid body formation method. We found defects in hematopoietic differentiation of FPD iPSCs, particularly towards megakaryopoiesis. Importantly, ZFN-mediated mutation correction rescued the hematopoietic differentiation defects with almost double the number of CD41a+/CD42a+ megakaryocytes produced from the corrected iPSCs.

Our results collectively demonstrate successful in vitro modeling of FPD using iPSC lines with an innovative approach to correct the RUNX1 mutation by gene targeting. Mutation correction rescues the hematopoietic defects, indicating that hematopoietic stem cell transplantation using patient-specific iPSC lines has great potential to treat the FPD patients in the future.

Disclosures:

Horwitz: United States Government: Consultancy, United States ex rel. Horwitz v. Amgen Inc., Civil Action No. C07-0248 (W.D. Wash.) Other.
Expanding The TLX1-Regulome In T Cell Acute Lymphoblastic Leukemia Towards Long Non-Coding RNAs
Authors: Durinck Kaat , Van der Meulen Joni , Ongenaert Maté , Volders Pieter-Jan , Wallaert Annelynn , Van Roy Nadine , Benoit Yves , Poppe Bruce , Mestdagh Pieter , Vandesompele Jo , Rondou Pieter , Soulier Jean , Van Vlierberghe Pieter , Speleman Frank
Published: October 2019

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive cancer that results from the malignant transformation of T-cell precursors and affects children, adolescents and adults. In T-ALL, genetic lesions in several possible oncogenes and tumor suppressors have been shown to cooperatively contribute to leukemogenesis. The TLX1 (T-cell leukemia homeobox protein-1, HOX11) oncoprotein is aberrantly expressed in in 5-10% of pediatric patients and 30% of adult T-ALL patients due to chromosomal translocations. Although many downstream protein coding targets genes of TLX1 have been identified, the non-coding network downstream of TLX1 remains elusive. In this study we expand the TLX1 regulome towards long non-coding RNAs (lncRNAs). Hereto we measured the transcriptional response of all protein coding genes and 12,000 lncRNAs following TLX1 knock down in the ALL-SIL cell line using a custom designed mRNA/lncRNA expression platform (Agilent). In addition, similar mRNA-lncRNA expression profiles of 64 primary T-ALL patient samples were generated which included five TLX1+ cases. To establish the direct transcriptional TLX1 targets, we generated TLX1 ChIP-sequencing data from ALL-SIL leukemic cells. We confirm direct regulation of previously established protein coding gene targets and de novo TLX1 motif discovery also identified RUNX1 as an important mediator of the global TLX1 transcriptional network (Della Gatta et al., Nature Medicine, 2012). Complementary to these data, our analysis for the first time establishes the TLX1 driven lncRNAome in thymocyte derived leukemic cells. Remarkably, the majority of TLX1 controlled lncRNAs were upregulated suggesting that they may be implicated in the TLX1 driven repression of protein coding gene expression. Finally, pairwise mRNA-lncRNA correlation analysis allowed functional annotation of TLX1 targeted lncRNAs. In conclusion, we present the first landscaping of the genome-wide binding pattern of TLX1 and provide evidence for a previously unestablished role of lncRNAs in the TLX1 regulatory network.

Disclosures:

No relevant conflicts of interest to declare.
Voriconazole Exposure and The Risk Of Cutaneous Squamous Cell Carcinoma In Allogeneic Hematopoietic Stem Cell Transplant Patients
Authors: Hashmi Shahrukh K , Wojenski Daniel , Bartoo Gabriel , Merten Julianna A. , Dierkhising Ross , Elazhary Rokea , Wilson John W , Wolf Robert , Patnaik Mrinal M. , Hogan William , Litzow Mark R.
Published: October 2019

Background

Voriconazole is a common antifungal medication used in allogeneic hematopoietic stem cell transplantation (allo-HSCT) patients. In solid organ transplantation, multiple studies have associated the use of voriconazole with the development of squamous cell carcinoma (SCC) post-transplant, but its association with SCC in allo-HSCT patients is unknown. We sought to determine this association.

Methods

After IRB approval, Mayo Clinic’s transplant database (2007-2012) was accessed and electronic charts of allo-HSCT patients were retrospectively reviewed. Voriconazole exposure was defined as exposure to voriconazole at any time during treatment of primary disease, prior to or following HSCT. Cumulative voriconazole exposure was defined as total days of voriconazole use following HSCT; days were not required to be consecutive. Two time-dependent voriconazole exposure variables were defined: (1) history of voriconazole exposure (yes/no) over time, and (2) cumulative days on voriconazole over time.

Results

404 patients underwent allo-HSCT during this timeframe, and 381 patients (table 1) were included in the final analysis. 23 patients were excluded (8 patients received multiple transplants, 9 patients were treated under pediatric protocols, 6 patients lacked research consent). 312/381 received voriconazole; other antifungal therapy included fluconazole (n=40), posaconazole (n=23), anidulafungin (n=1), and caspofungin (n=5). Median duration of cumulative days of voriconazole was 214 (range 2 -1553). SCC developed in 26/312 exposed to voriconazole and in 1/69 who received alternative antifungals. Cumulative incidence of SCC at 1 year was 3%, 2 years was 8%, 3 years was 13%, 4 years was 14%, and at 5 years was 19% (figure 1). Cumulative days of voriconazole use was found to be a risk factor for the development of SCC, and this relationship persisted in a multivariate model using previously identified risk factors (gender, age at transplant, TBI conditioning regimen, skin cancer pre-HSCT, chronic GVHD) as covariates (HR 1.859 for each 180 days of use, p<0.001). History of prior voriconazole exposure was not associated with an increased risk of SCC after covariate adjustment (HR 2.436, p=0.2369).

Conclusion

This is the first study to establish cumulative days of voriconazole use as a risk factor for SCC development following allo-HSCT, and may help guide appropriate antifungal prophylaxis in this patient population which is already at an increased risk of developing skin cancers.

Disclosures:

No relevant conflicts of interest to declare.
Epo Dependent Signaling In Macrophages Regulates Stress Erythropoiesis
Authors: Paulson Robert F. , Xiang Jie , Hariharan Sneha
Published: October 2019

Steady State erythropoiesis occurs in the bone marrow and is primarily homeostatic. In response to anemic stress the need for new erythrocytes quickly outpaces the erythropoietic capacity of steady state erythropoiesis. At these times, stress erythropoiesis predominates. Stress erythropoiesis is best understood in mice where this process is primarily extra-medullary occurring in the adult spleen and liver and in the fetal liver during development. Stress erythropoiesis utilizes progenitors and signals that are distinct from steady state erythropoiesis. Using a variety of experimental systems, we have developed a model for stress erythropoiesis during the recovery from anemic stress. This recovery can be divided into three stages. Amplification of progenitors that exhibit stem cell properties, the induction of a signal that promotes the switch from amplifying stress progenitors to differentiating stress progenitors and the final stage where stress progenitors rapidly differentiate into new erythrocytes. We have identified specific stress progenitor populations at each stage on this process as well as the signals that regulate the amplification, the switch to differentiation and differentiation of stress erythroid progenitors. Here we show that macrophage dependent signals play key roles at each stage of stress erythropoiesis. The transition from amplifying stress erythroid progenitors to differentiating stress erythroid progenitors is mediated by Epo dependent signaling in macrophages which changes the signals made by the macrophage microenvironment from those that promote amplification (Wnt family factors) to those that promote differentiation (PGE2). This paradigm is true for murine and human stress erythroid progenitors. This analysis reveals a dynamic interplay between progenitor cells, the macrophage microenvironment and hypoxic tissues in vivo during the recovery from anemic stress.

Disclosures:

No relevant conflicts of interest to declare.
A Novel Path for ATRA Differentiation Therapy in Acute Myeloid Leukemia with Isocitrate Dehydrogenase Mutations
Authors: Sarry Jean-Emmanuel , Boutzen Helena , Récher Christian
Published: October 2019

Acute myeloid leukemia (AML) is characterized by accumulation of malignant blasts with impaired differentiation programs due to recurrent mutations, among which IDH mutations occur in 15% of AML patients. These mutations lead to a block in erythroid commitment while they may also bias hematopoietic differentiation to myeloid lineage. Interestingly, Lyn tyrosine kinase is required for erythroid differentiation and we have observed a reduction of Lyn expression in the presence of IDH1-R132H mutation. It is also a negative regulator of ATRA-induced granulocytic differentiation. Accordingly, we hypothesized that IDH mutations may sensitize AML cells to ATRA-induced differentiation.

Here, we report that clinically achievable doses of ATRA are sufficient to trigger differentiation specifically on AML cell lines, primary patient samples and xenograft mice models carrying IDH1 mutation as observed by an increase in CD11b expression, granulocytic enzyme activity and morphologic changes in May-Grunwald-Giemsa staining. We also showed that ATRA-induced terminal granulocytic differentiation increases apoptosis while decreases proliferation and colony formation specifically in IDH1 mutant cells. Moreover, inhibition of IDH1-R132H activity reduced ATRA-sensitivity while increasing expression of IDH mutation correlated with highest ATRA sensitivity. Furthermore, treatment with a cell-permeable form of the oncometabolite specifically produced by the mutant (eg. 2-HydroxyGlutarate) sensitized AML cells to ATRA-induced differentiation. Finally, because ATRA-induced differentiation triggers a transient increase of Lyn activation, its association with Lyn inhibitors synergistically increased ATRA-induced differentiation of IDH mutant blasts.

In summary, our results showed that IDH mutations by producing 2-HG sensitized leukemic blasts to ATRA and that this synergizes with Lyn inhibition. Since 2HG concentration reaches millimolar in AML patient serum and is 100-fold higher in IDH mutated patients than in non-mutated ones, we would predict a strong efficacy and specificity of ATRA. Furthermore, as IDH mutations are systematically conserved at relapse, this therapeutic strategy might be promising to achieve a long-term remission specifically for this AML patient subgroup.

Disclosures

No relevant conflicts of interest to declare.
Interacting populations affecting proliferation of leukemic cells in culture
Authors: Aye MT , Till JE , McCulloch EA
Published: October 2019

Peripheral blood cells from three patients with acute leukemic have been studied using a suspension culture method previously described.1 Cytogenetic studies in two of the patients permitted the identification of the proliferating cells in the cultures as being derived from a leukemic population. Cell separation studies using velocity sedimentation supported the concept that growth of the leukemic cells in culture is dependent on an interaction between two populations of leukemic cells.
Sex hormones and the regulation of erythroid spleen colonies development of fetal liver origin
Authors: Bleiberg I , Perah G
Published: October 2019

The development of erythroid colonies of fetal liver hemopoietic cell origin in adult irradiated polycythemic mice was studied. It was found that orchidectomy sharply reduced the number of erythroid colonies developed in the spleen of these polycythemic male recipients. Estrogen injection to the orchidectomized polycythemic recipient did not further decrease the number of erythroid colonies developed. It is concluded that the development of erythroid colonies of fetal liver origin in polycythemic male recipients is maintained mainly by testicular testosterone. The complete suppression of these colonies in female recipients does not seem to be a result of inhibition by estrogen.
Tolerance to the granulocyte-releasing and colony-stimulating factor elevating effects of endotoxin
Authors: Quesenberry P , Halperin J , Ryan M , Stohlman F Jr
Published: October 2019

Injection of Salmonella typhosa endotoxin into either CF1 or C57bl/6J mice leads to prompt increases in serum colony-stimulating factor (CSF). Repeated injections of endotoxin result in a dose-related hyporesponsiveness or tolerance to this effect. Tolerance is seen after either intravenous (i.v.) or intraperitoneal (i.p.) routes of administration or challenge and occurs after one to two preinjections. Cross-tolerance to heterologous endotoxin (Escherichia coli) was also shown. This cross-tolerance is complete immediately after cessation of preinjections, but partial at later time intervals. Levels of a serum inhibitor of colony growth were decreased in tolerant mice, although this decrease is not statistically significant. Tolerant mice injected with endotoxin release granulocytes from the bone marrow normally, in spite of the absence of a CSF response. This suggests that neutrophil releasing activity (NRA) and CSF are separate entities. A marked marrow granulocytic hyperplasia develops after 7 or 20 days of endotoxin injections, despite the tolerance to the CDF-elevating effect of endotoxin. This granulocytic hyperplasia could still be mediated by serum CSF increases. A negative medullary feed-back secondary to the repetitive release of marrow granulocytes, however, is an equally plausible mechanism for the stimulation of granulocyte production. It is also possible that the decrease in serum inhibitors played a role in the sustained increase in granulopoiesis seen here.
A measurement technique for cell adhesiveness
Authors: Young IT , Sher SE
Published: October 2019

Determination of the percentage of cells in clumps on a stained smear of human peripheral blood porvided a useful, accurate technique for measuring cell adhesiveness. Smears of human peripheral blood drawn with EDTA were prepared on a blood slide centrifuge, stained, and examined under a light microscope. Statistical analysis showed that the method resulted in a Poisson distribution of particles on the slide, where a particle was considered to be a simple cell, or two or more cells which appeared to be touching, Analysis of the distributions of erythrocytes and leukocytes showed that clumps were formed before the cells were deposited on the slide. When adhesiveness of erythrocytes or leukocytes was increased by incubation with antiserum to the corresponding cell type, the percentage of that cell type in clumps increased proportionately, Preliminary results using the method showed that normal human donors had similar to 1% of their erythrocytes and 1- 5% of their leukocytes in clumps. In chronic myelocytic leukemia, as many as 60% of the leukocytes were in clumps.
Total folate binding capacity of normal human plasma, and variations in uremia, cirrhosis, and pregnancy
Authors: Colman N , Herbert V
Published: October 2019

The current study presents evidence that all human serum contains a class of high-affinity folate binders (KA=2.8 X10(10 liters/mole), which migrate as a single peak on gel filtration. Failure of previous studies to detect this characteristic in all but a minority of subjects is attributable to its variable, often total, saturation. Direct measurement of the total folate binding capacity (TFBC) has been made possible by dissociation of endogenous folate-binder complexes at acid pH, removal of free folate by coated charcoal, and radiofolate tagging. This procedure does not appear to significantly denature the binders, which release and rebind similar quantities of 3H-PGA. In 20 normal subjects, TFBC ranged from 100 to 325 pg/ml (mean+/-SE = 174+/-16), and was always at least 33% saturated. In three clinical conditions, all associated with elevated unsaturated folate binding capacity, three different patterns emerged when TFBC was also measured. Uremic subjects had significantly elevated mean TFBC with normal saturation. In cirrhotic subjects, mean TFBC approximated normal, but saturation was significantly decreased. In pregnancy, two groups were seen: one with increased TFBC and the other with a normal TFBC, some of whom had decreased saturation. Lactobacillus casei serum folate level was about 30 times greater than the TFBC; there was no correlation between the two measurements.
Cytogenetic evidence for recurrence of acute myelogenous leukemia after allogeneic bone marrow transplantation in donor hematopoietic cells
Authors: Elfenbein GJ , Brogaonkar DS , Bias WB , Burns WH , Saral R , Sensenbrenner LL , Tutschka PJ , Zaczek BS , Zander AR , Epstein RB , Rowley JD , Santos GW
Published: October 2019

A 22-yr-old man with acute myelocytic leukemia received a bone marrow transplant from a genotypically HLA-identical female sibling after cyclophosphamide preparation. He remained in complete remission for 18 mo, when he developed a chloroma in the perineum. The chloroma was treated with local radiotherapy. The chloroma recurred 8 mo later and was treated with radiotherapy followed by combination chemotherapy. At 34 mo after transplant, marrow relapse and chloroma were documented. The first chloroma contained host cells by fluorescent Y-chromatin body analyses of interphase nuclei. All metaphase cells and karyotypes from peripheral blood and marrow samples showed no evidence of host cells from 3 wk after transplant through the time of marrow relapse. Data from autosomal and sex chromosome studies indicate that the marrow relapse occurred in cells of donor origin. A new consistent chromosome abnormality [45, X, -X, t(8;21) (q22; q22)] was observed in a majority of donor cells. The patient received a second bone marrow transplant from the same donor after preparation with busulfan and cyclophosphamide and attained a complete remission with full hematologic engraftment.
Correlation of serum IgD level with clinical and histologic parameters in Hodgkin disease
Authors: Corte G , Ferraris AM , Rees JK , Bargellesi A , Hayhoe FG
Published: October 2019

The concentration of serum IgD was measured in 100 patients with Hodgkin disease; 65 had 3--50-fold increases in IgD levels. Several parameters were found to influence serum IgD concentration: IgD level in older patients (greater than 50 yr) was significantly lower than in the younger patients (P less than 18 yr). IgD concentration was significantly higher in splenectomized than in nonsplenectomized patients (p less than 0.005). Therapy was found to depress IgD concentration, which fell to a value significantly lower than in untreated patients (p less than 0.05). An interesting correlation was found between IgD levels and histologic type of the disease, lower levels being preferentially associated with the lymphocyte predominance type and higher with the lymphocyte dipletion type. The logarithms of the means of these two groups were significantly different from the overall mean of the disease (p less than 0.05 and p less than 0.0005, respectively). Mixed cellularity and nodular sclerosing showed intermediate values.
Hereditary dyserythropoiesis with abnormal membrane folate transport
Authors: Howe RB , Branda RF , Douglas SD , Brunning RD
Published: October 2019

Dyserythropoiesis, which morphologically and serologically resembles congenital dyserythropoietic anemia type III but is not accompanied by anemia, is described in a young man. In addition to striking gigantism and multinuclearity of erythroid precursors, electron microscopy revealed widening of nuclear pores, nuclear clefts, and cytoplasmic inclusions. Membrane transport of 5-methyltetrahydrofolate by the patient's red cells was markedly reduced; total uptake, uptake velocity, and maximal velocity of uptake were all significantly less than in controls. In contrast, red cell uptake of pteroylglutamic acid was normal. Bone marrow cells in culture also showed decreased 5- methyltetrahydrofolate uptake, as well as very low thymidine incorporation. Because folate uptake by mitogen-stimulated lymphocytes was normal, the defect apparently does not involve all cell lines. These results suggest that a specific membrane defect, affecting the carrier system for reduced folate compounds, is present in this patient's erythrocytes, and perhaps, their bone marrow precursors.
Mucosal iron transport by rat intestine
Authors: Savin MA , Cook JD
Published: October 2019

Using highly sensitive 2-site immunoradiometric assays, we examined the relationship between iron absorption from closed intestinal loops and transferrin and ferritin concentrations in isolated duodenal mucosal cells. As in prior studies, mucosal ferritin correlates inversely with iron absorption and directly with body iron stores as measured by the concentration of nonheme iron in liver. Mucosal transferrin, on the other hand, varies directly with both the total mucosal uptake of radioiron and the proportion of this radioiron transferred from the mucosa to the carcass. The highest correlation with iron absorption was observed with the transferrin-ferritin ratio in isolated mucosal cells. These results suggest that there are two functionally distinct iron- binding compartments in the duodenal mucosa. One is a strong compartment, ferritin, and the other is a transport compartment, transferrin. Control of iron absorption by the intestinal mucosa is closely tied to the balance between these two intracellular iron compartments.
The mouse pale ear pigment mutant as a possible animal model for human platelet storage pool deficiency
Authors: Novak EK , Hui SW , Swank RT
Published: October 2019

The mouse pigment mutant pale ear, ep/ep, which has a defect in kidney lysosomal enzyme secretion, had prolonged bleeding on experimental injury. Platelet counts and platelet protein did not differ from normal. There was, however, a deficiency in the platelet dense granule contents, serotonin, ATP, and ADP. Furthermore, a marked reduction of platelet dense granules was observed by electron microscopy. The results suggest that pale ear is a useful animal model in the study of platelet storage pool disease. Studies on this mutant and other pigment mutants have established that one gene can regulate at least three subcellular organelles, including the melanosome, the lysosome, and the platelet dense granule.
Enhancement of iron chelation by desferrioxamine entrapped in red blood cell ghosts
Authors: Green R , Miller J , Crosby W
Published: October 2019

We have exploited the physiologic mechanism for removal of red cells from the circulation to target the iron chelator desferrioxamine to reticuloendothelial iron stores. Compared with free desferrioxamine injected intravenously, the same dose of desferrioxamine entrapped in resealed red blood cell ghosts resulted in a fourfold to fivefold increase in excretion of radioiron in rats with a selective 59Fe radiolabel of reticuloendothelial iron stores. Desferrioxamine in red cell ghosts did not enhance excretion in rats with selective radiolabeling of parenchymal iron stores. In rats with uniformly radiolabeled iron stores, desferrioxamine in red cell ghosts produced an eightfold to ninefold greater loss of iron in the urine free desferrioxamine intravenously or by slow subcutaneous infusion. Desferrioxamine in red cell ghosts resulted in significantly greater fecal excretion of iron than intravenous desferrioxamine, but desferrioxamine in red cell ghosts and subcutaneous desferrioxamine infusion resulted in similar fecal iron excretion. Clinical application of the red cell ghost method for administration of desferrioxamine and other iron chelators may ber useful for improvement of iron chelation efficiency.
Malignant monoblasts can function as effector cells in natural killer cell and antibody-dependent cellular cytotoxicity assays
Authors: Hokland P , Hokland M , Ellegaard J
Published: October 2019

This is the first report describing natural killer (NK) and antibody- dependent cellular cytotoxicity (ADCC) of malignant monoblasts. Pure acute monoblastic leukemia was diagnosed in bone marrow aspirations from two patients by use of conventional cytochemical methods as well as multiple immunologic techniques including detection of ALL antigens and terminal transferase. The malignant cells were subsequently found to be potent effectors in NK and ADCC assays. Addition of partially purified alpha-interferon to the in vitro cultures was found to have an enhancing effect on NK activity, whereas no modulation was seen in ADCC. These findings are discussed in the light of our present knowledge of lymphoid NK cells.
Acquired von Willebrand's disease in association with Wilm's tumor: regression following treatment
Authors: Scott JP , Montgomery RR , Tubergen DG , Hays T
Published: October 2019

A 9-yr-old female presented with a Wilm's tumor and a coagulopathy consistent with von Willebrand's disease. Factor VIII procoagulant activity (VIII C), factor VIII related antigen (VIIIR:Ag), and von Willebrand factor activity (VIII:vWf) were decreased. There was no evidence for a circulating inhibitor of the factor VIII molecular complex. von Willebrand's antigen II (vW AgII), which is deficient in hereditary von Willebrand's disease, was decreased below detectable levels in this patient. The coagulation studies, VIIIR:Ag, and vW AgII levels returned to normal following therapy of the Wilm's tumor. Wilm's tumor must be included as one of the malignancies associated with acquired von Willebrand's disease. Immunofluorescent studies of the tumor specimen showed normal endothelial staining of VIIIR:Ag by semiquantitative techniques and a lack of specific tumor adsorption of VIIIR:Ag The presence of normal amounts of tissue VIIIR:Ag has not previously been demonstrated in acquired von Willebrand's disease. Since we failed to demonstrate an inhibitor in the plasma in this patient, the etiology of the acquired von Willebrand's disease in this patient appears to differ from other cases of acquired von Willebrand's disease. The finding that vW AgII is decreased in this patient, similar to that reported in hereditary von Willebrand's disease, supports the close association of vW AgII to VIIIR:Ag, even though they are immunologically and biochemically distinct.
Human trophoblasts: cellular source of colony-stimulating activity in placental tissue
Authors: Ruscetti FW , Chou JY , Gallo RC
Published: October 2019

Colony-stimulating activity (CSA) is a class of protein factors that stimulates the in vitro growth and differentiation of hematopoietic committed stem cells into mature granulocytes and macrophages. In man, production of CSA is mediated by monocytes-macrophages, lymphocyte, and endothelial cells. One of the best studied and most potent sources of CSA is conditioned media derived from cultured human placenta. The cellular source of this placental CSA was studied using cloned term placental cell lines induced by a simian virus 40 (SV-40) Wild-Type (wt) or temperature sensitive (tsA) mutants. Conditioned media from SV- 40 wt-transformed placental cells grown at 37 degrees C and tsA- transformed placental cells grown at 33 degrees C (the temperature at which the cells exhibit the transformed phenotype) and at 40 degrees C (temperature at which the cells express a normal differentiated phenotype) contained high levels of CSA. At the restricted temperature (40 degrees C), these cell lines expressed normal trophoblastic characteristics in that they produced human chorionic gonadotropin, pregnancy-specific-beta1-glyco protein, and placental alkaline phosphatase, indicating that the SV-40 transformation has not interfered with normal cellular functions of these trophoblasts. The CSA released by these cell lines resemble those of CM from fresh placental cells, in that the level of activity is high and that formation of both granulocyte/macrophage and eosinophil colonies is stimulated.