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Georgalas I, Makris G, Papaconstantinou D, Petrou P, Chalkiadaki E, Droutsas K, Andreanos K, Kanakis M. A Pilot Optical Coherence Tomography Angiography Study on Superficial and Deep Capillary Plexus Foveal Avascular Zone in Patients With Beta-Thalassemia Major. Invest Ophthalmol Vis Sci 2020; 60:3887-3896. [PMID: 31529120 DOI: 10.1167/iovs.19-27291] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To investigate foveal avascular zone (FAZ) changes in the superficial (SCP) and deep (DCP) capillary plexuses in beta-thalassemia major (BTM) patients, as shown in optical coherence tomography angiography. Methods Nonrandomized, comparative case series of 54 eyes of 27 BTM patients and 46 eyes of 23 healthy controls, utilizing an automated FAZ detection algorithm. Measurements included FAZ area and FAZ shape descriptors (convexity, circularity, and contour temperature). Results were compared between the two groups, and correlated to iron load and chelation therapy parameters. Results SCP and DCP FAZ area were not significantly different between the control and BTM groups (P = 0.778 and P = 0.408, respectively). The same was true regarding SCP FAZ convexity (P = 0.946), circularity (P = 0.838), and contour temperature (P = 0.907). In contrast, a statistically significant difference was detected between controls and BTM group regarding DCP FAZ convexity (P = 0.013), circularity (P = 0.010), and contour temperature (P = 0.014). Desferrioxamine dosage was strongly correlated to the DCP area (r = 0.650, P = 0.05) and liver magnetic resonance imaging/T2-star to DCP circularity (r = -0.492, P = 0.038). Correlations were also revealed between urine Fe excretion and DCP convexity (r = 0.531, P = 0.019), circularity (r = 0.661, P = 0.002), and contour temperature (r = -0.591, P = 0.008). Conclusions Retinal capillary plexuses and especially DCP seem to present unique morphologic changes in BTM patients, not in the FAZ area, but in specific shape descriptors, indicating minor but detectable FAZ changes. These changes correlate well with iron load and chelation therapy parameters. Their clinical importance and pathophysiologic implications remain to be elucidated through further studies.
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Affiliation(s)
- Ilias Georgalas
- First Department of Ophthalmology, National and Kapodistrian University of Athens, G. Gennimatas Hospital, Athens, Greece
| | - Georgios Makris
- Department of Ophthalmology, G. Gennimatas Hospital, Athens, Greece
| | - Dimitrios Papaconstantinou
- First Department of Ophthalmology, National and Kapodistrian University of Athens, G. Gennimatas Hospital, Athens, Greece
| | - Petros Petrou
- First Department of Ophthalmology, National and Kapodistrian University of Athens, G. Gennimatas Hospital, Athens, Greece
| | - Evangelia Chalkiadaki
- First Department of Ophthalmology, National and Kapodistrian University of Athens, G. Gennimatas Hospital, Athens, Greece
| | - Konstantinos Droutsas
- First Department of Ophthalmology, National and Kapodistrian University of Athens, G. Gennimatas Hospital, Athens, Greece
| | - Konstantinos Andreanos
- First Department of Ophthalmology, National and Kapodistrian University of Athens, G. Gennimatas Hospital, Athens, Greece
| | - Menelaos Kanakis
- Department of Ophthalmology, Patras University School of Medicine, Rion, Patras, Greece
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Uaprasert N, Satitthummanid S, Akkawat B, Sutcharitchan P, Rojnuckarin P. Vascular and hemostatic alterations associated with pulmonary hypertension in β-thalassemia hemoglobin E patients receiving regular transfusion and iron chelation. Thromb Res 2018; 174:104-112. [PMID: 30584959 DOI: 10.1016/j.thromres.2018.12.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 11/18/2018] [Accepted: 12/19/2018] [Indexed: 01/19/2023]
Abstract
INTRODUCTION Pulmonary hypertension (PH) is the commonest cardiac complication in β-thalassemia intermedia, including β-thalassemia/hemoglobin E (β-thal/HbE), and is strongly associated with splenectomy. We aimed to define the prevalence and comprehensively explore mechanisms of PH in β-thal/HbE patients receiving regular transfusion and iron chelation, which were reported to alleviate PH. MATERIALS AND METHODS β-Thal/HbE patients receiving regular transfusion and iron chelation over one year were enrolled. Patients at risk for PH were defined by tricuspid-regurgitant-jet-velocity (TRV) ≥ 2.5 m/s. Laboratory and echocardiographic variables were compared with healthy controls. RESULTS There were 68 β-thal/HbE, including 31 (45.6%) splenectomized patients, and 38 controls included for analysis. PH was detected in 29 β-thal/HbE (42.6%). β-Thal/HbE with PH had a significant reduction in nitric oxide metabolites (NOx) but elevations in thrombin-antithrombin (TAT) complex, soluble thrombomodulin (sTM), endothelin-1 (ET-1) and flow-mediated dilation (FMD) values compared to those without PH (all, p < 0.05). TRV was significantly correlated with NOx, TAT, sTM, ET-1 and FMD values (r = -0.514, r = 0.281, r = 0.313, r = 0.245 and r = -0.474; all p < 0.05). Erythropoietic activity, serum ferritin, circulating total tissue factor (TF) antigen, microparticle-associated TF activity, microparticle's procoagulant activity and soluble p-selectin levels were not different between PH and non-PH subgroups. Notably, there were no significant associations between splenectomy and PH. CONCLUSIONS PH remains prevalent in β-thal/HbE patients receiving long-term transfusion and iron chelation. PH is not associated with splenectomy status but correlated with NO depletion, TF-independent hypercoagulability and endothelial perturbation.
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Affiliation(s)
- Noppacharn Uaprasert
- Division of Hematology, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok 10330, Thailand.
| | - Sudarat Satitthummanid
- Division of Cardiology, Department of Medicine, Faculty of Medicine, Chulalongkorn University and Cardiac Center, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok 10330, Thailand
| | - Benjaporn Akkawat
- Division of Hematology, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok 10330, Thailand
| | - Pranee Sutcharitchan
- Division of Hematology, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok 10330, Thailand
| | - Ponlapat Rojnuckarin
- Division of Hematology, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok 10330, Thailand
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Hirsch RE, Sibmooh N, Fucharoen S, Friedman JM. HbE/β-Thalassemia and Oxidative Stress: The Key to Pathophysiological Mechanisms and Novel Therapeutics. Antioxid Redox Signal 2017; 26:794-813. [PMID: 27650096 PMCID: PMC5421591 DOI: 10.1089/ars.2016.6806] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 09/16/2016] [Indexed: 01/19/2023]
Abstract
SIGNIFICANCE Oxidative stress and generation of free radicals are fundamental in initiating pathophysiological mechanisms leading to an inflammatory cascade resulting in high rates of morbidity and death from many inherited point mutation-derived hemoglobinopathies. Hemoglobin (Hb)E is the most common point mutation worldwide. The βE-globin gene is found in greatest frequency in Southeast Asia, including Thailand, Malaysia, Indonesia, Vietnam, Cambodia, and Laos. With the wave of worldwide migration, it is entering the gene pool of diverse populations with greater consequences than expected. CRITICAL ISSUES While HbE by itself presents as a mild anemia and a single gene for β-thalassemia is not serious, it remains unexplained why HbE/β-thalassemia (HbE/β-thal) is a grave disease with high morbidity and mortality. Patients often exhibit defective physical development, severe chronic anemia, and often die of cardiovascular disease and severe infections. Recent Advances: This article presents an overview of HbE/β-thal disease with an emphasis on new findings pointing to pathophysiological mechanisms derived from and initiated by the dysfunctional property of HbE as a reduced nitrite reductase concomitant with excess α-chains exacerbating unstable HbE, leading to a combination of nitric oxide imbalance, oxidative stress, and proinflammatory events. FUTURE DIRECTIONS Additionally, we present new therapeutic strategies that are based on the emerging molecular-level understanding of the pathophysiology of this and other hemoglobinopathies. These strategies are designed to short-circuit the inflammatory cascade leading to devastating chronic morbidity and fatal consequences. Antioxid. Redox Signal. 26, 794-813.
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Affiliation(s)
- Rhoda Elison Hirsch
- Department of Medicine (Hematology), Albert Einstein College of Medicine, Bronx, New York
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Nathawut Sibmooh
- Department of Pharmacology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Suthat Fucharoen
- Thalassemia Research Center, Institute of Molecular Biosciences, Mahidol University, Nakornpathom, Thailand
| | - Joel M. Friedman
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, New York
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Depleted nitric oxide and prostaglandin E 2 levels are correlated with endothelial dysfunction in β-thalassemia/HbE patients. Int J Hematol 2017; 106:366-374. [PMID: 28474291 DOI: 10.1007/s12185-017-2247-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 05/01/2017] [Accepted: 05/01/2017] [Indexed: 01/22/2023]
Abstract
Mechanisms of vascular disorders in β-thalassemia/HbE patients remain poorly understood. In the present study, we aimed to determine the presence of endothelial dysfunction and its association with altered vascular mediators in this population. Forty-three β-thalassemia/HbE patients without clinically documented vascular symptoms and 43 age-sex-matched healthy controls were enrolled. Endothelial function was assessed using flow-mediated dilatation (FMD) before and after administration of nitroglycerine (NTG). β-Thalassemia/HbE patients showed a significant endothelial dysfunction using FMD. The percentage change in the brachial artery diameter before NTG was significantly lower in the thalassemia group compared to the control (5.0 ± 5.9 vs. 9.0 ± 4.0%, p < 0.01) while no significant differences after NTG (18.4 ± 8.3 vs. 17.8 ± 6.3%, p = 0.71). Plasma nitric oxide metabolites (NO x ) and prostaglandin E2 (PGE2) levels were significantly decreased in β-thalassemia/HbE (117.2 ± 27.3 vs. 135.8 ± 11.3 µmol/L, p < 0.01) and (701.9 ± 676.0 vs. 1374.7 ± 716.5 pg/mL, p < 0.01), respectively, while a significant elevation in soluble thrombomodulin levels in β-thalassemia/HbE (3587.7 ± 1310.0 vs. 3093.9 ± 583.8 pg/mL, p = 0.028). NO x and PGE2 levels were significantly correlated with FMD (r = 0.27, p = 0.025) and (r = 0.35, p = 0.003), respectively. These findings suggest roles for endothelial mediators and a new mechanism underlying endothelial dysfunction in β-thalassemia/HbE patients.
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Morris CR, Kim HY, Klings ES, Wood J, Porter JB, Trachtenberg F, Sweeters N, Olivieri NF, Kwiatkowski JL, Virzi L, Hassell K, Taher A, Neufeld EJ, Thompson AA, Larkin S, Suh JH, Vichinsky EP, Kuypers FA. Dysregulated arginine metabolism and cardiopulmonary dysfunction in patients with thalassaemia. Br J Haematol 2015; 169:887-98. [PMID: 25907665 DOI: 10.1111/bjh.13452] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 03/07/2015] [Indexed: 01/19/2023]
Abstract
Pulmonary hypertension (PH) commonly develops in thalassaemia syndromes, but is poorly characterized. The goal of this study was to provide a comprehensive description of the cardiopulmonary and biological profile of patients with thalassaemia at risk for PH. A case-control study of thalassaemia patients at high versus low PH-risk was performed. A single cross-sectional measurement for variables reflecting cardiopulmonary status and biological pathophysiology were obtained, including Doppler-echocardiography, 6-min-walk-test, Borg Dyspnoea Score, New York Heart Association functional class, cardiac magnetic resonance imaging (MRI), chest-computerized tomography, pulmonary function testing and laboratory analyses targeting mechanisms of coagulation, inflammation, haemolysis, adhesion and the arginine-nitric oxide pathway. Twenty-seven thalassaemia patients were evaluated, 14 with an elevated tricuspid-regurgitant-jet-velocity (TRV) ≥ 2·5 m/s. Patients with increased TRV had a higher frequency of splenectomy, and significantly larger right atrial size, left atrial volume and left septal-wall thickness on echocardiography and/or MRI, with elevated biomarkers of abnormal coagulation, lactate dehydrogenase (LDH) levels and arginase concentration, and lower arginine-bioavailability compared to low-risk patients. Arginase concentration correlated significantly to several echocardiography/MRI parameters of cardiovascular function in addition to global-arginine-bioavailability and biomarkers of haemolytic rate, including LDH, haemoglobin and bilirubin. Thalassaemia patients with a TRV ≥ 2·5 m/s have additional echocardiography and cardiac-MRI parameters suggestive of right and left-sided cardiac dysfunction. In addition, low arginine bioavailability may contribute to cardiopulmonary dysfunction in β-thalassaemia.
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Affiliation(s)
- Claudia R Morris
- Department of Pediatrics, Division of Emergency Medicine, Emory University School of Medicine, Emory Children's Centre for Cystic Fibrosis and Airways Disease Research, Atlanta, GA, USA
| | - Hae-Young Kim
- New England Research Institutes Watertown, Watertown, MA, USA
| | - Elizabeth S Klings
- The Pulmonary Centre, Boston University School of Medicine, Boston, MA, USA
| | - John Wood
- Children's Hospital of Los Angeles, Los Angeles, CA, USA
| | | | | | - Nancy Sweeters
- Hematology/Oncology, UCSF Benioff Children's Hospital Oakland, Oakland, CA, USA
| | | | | | - Lisa Virzi
- New England Research Institutes Watertown, Watertown, MA, USA
| | - Kathryn Hassell
- Division of Blood Diseases and Resources, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Ali Taher
- American University of Beirut, Beirut, Lebanon
| | | | - Alexis A Thompson
- Haematology, Oncology & Stem Cell Transplant, Children's Memorial Hospital, Chicago, IL, USA
| | - Sandra Larkin
- Children's Hospital Oakland Research Institute, Oakland, CA, USA
| | - Jung H Suh
- Children's Hospital Oakland Research Institute, Oakland, CA, USA
| | - Elliott P Vichinsky
- Hematology/Oncology, UCSF Benioff Children's Hospital Oakland, Oakland, CA, USA
| | - Frans A Kuypers
- Children's Hospital Oakland Research Institute, Oakland, CA, USA
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Endothelial nitric oxide synthase gene intron 4 variable number tandem repeat polymorphism in β-thalassemia major: relation to cardiovascular complications. Blood Coagul Fibrinolysis 2015; 26:419-25. [PMID: 25699607 DOI: 10.1097/mbc.0000000000000277] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Endothelial nitric oxide synthase (eNOS), an enzyme that generates nitric oxide, is a major determinant of endothelial function. Several eNOS gene polymorphisms have been reported as 'susceptibility genes' in various human diseases states, including cardiovascular, pulmonary and renal diseases. We studied the 27-base pair tandem repeat polymorphism in intron 4 of eNOS gene in 60 β-thalassemia major (β-TM) patients compared with 60 healthy controls and assessed its role in subclinical atherosclerosis and vascular complications. Patients were evaluated stressing on transfusion history, splenectomy, thrombotic events, echocardiography and carotid intima-media thickness (CIMT). Analysis of eNOS intron 4 gene polymorphism was performed by PCR. No significant difference was found between β-TM patients and controls with regard to the distribution of eNOS4 alleles or genotypes. The frequency of eNOS4a allele (aa and ab genotypes) was significantly higher in β-TM patients with pulmonary hypertension or cardiomyopathy. Logistic regression analysis revealed that eNOS4a allele was an independent risk factor for pulmonary hypertension in β-TM patients [odds ratio (OR) 2.2, 95% confidence interval (95% CI) 1.19-5.6; P < 0.001]. We suggest that eNOS intron 4 gene polymorphism is related to endothelial dysfunction and subclinical atherosclerosis and could be a possible genetic marker for prediction of increased susceptibility to cardiovascular complications.
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Suvachananonda T, Wankham A, Srihirun S, Tanratana P, Unchern S, Fucharoen S, Chuansumrit A, Sirachainan N, Sibmooh N. Decreased nitrite levels in erythrocytes of children with β-thalassemia/hemoglobin E. Nitric Oxide 2013; 33:1-5. [DOI: 10.1016/j.niox.2013.04.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 04/10/2013] [Accepted: 04/28/2013] [Indexed: 01/19/2023]
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Dioguardi FS. The challenge of complexity and arginine metabolism. Am J Clin Nutr 2013; 98:507-8. [PMID: 23873681 DOI: 10.3945/ajcn.113.065011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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9
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Morris CR, Kim HY, Wood J, Porter JB, Klings ES, Trachtenberg FL, Sweeters N, Olivieri NF, Kwiatkowski JL, Virzi L, Singer ST, Taher A, Neufeld EJ, Thompson AA, Sachdev V, Larkin S, Suh JH, Kuypers FA, Vichinsky EP. Sildenafil therapy in thalassemia patients with Doppler-defined risk of pulmonary hypertension. Haematologica 2013; 98:1359-67. [PMID: 23585527 DOI: 10.3324/haematol.2012.082065] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Pulmonary hypertension is a common but often overlooked complication associated with thalassemia syndromes. There are limited data on the safety and efficacy of selective pulmonary vasodilators in this at-risk population. We, therefore, designed a 12-week, open-label, phase 1/2, pilot-scale, proof-of-principle trial of sildenafil therapy in 10 patients with β-thalassemia and at increased risk of pulmonary hypertension based on an elevated tricuspid regurgitant jet velocity >2.5 m/s on Doppler-echocardiography. Variables compared at baseline and after 12 weeks of sildenafil treatment included Doppler-echocardiographic parameters, 6-minute walked distance, Borg Dyspnea Score, New York Heart Association functional class, pulmonary function, and laboratory parameters. Treatment with sildenafil resulted in a significant decrease in tricuspid regurgitant jet velocity by 13.3% (3.0±0.7 versus 2.6±0.5 m/s, P=0.04), improved left ventricular end systolic/diastolic volume, and a trend towards a improved New York Heart Association functional class. No significant change in 6-minute walked distance was noted. Sildenafil was well tolerated, although minor expected adverse events were commonly reported. The total dose of sildenafil (mg) was strongly correlated with percent change in nitric oxide metabolite concentration in the plasma (ρ=0.80, P=0.01). There were also significant increases in plasma and erythrocyte arginine concentrations. Our study suggests that sildenafil is safe and may improve pulmonary hemodynamics in patients at risk of pulmonary hypertension; however, it was not demonstrated to improve the distance walked in 6 minutes. Clinical trials are needed to identify the best treatment strategy for pulmonary hypertension in patients with β-thalassemia. (clinicaltrials.gov identifier: NCT00872170).
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Affiliation(s)
- Claudia R Morris
- Department of Pediatrics, Division of Emergency Medicine, Emory-Children’s Center for Developmental Lung Biology,Emory University School of Medicine, Atlanta, GA, USA.
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Increased level of myeloid-derived suppressor cells, programmed death receptor ligand 1/programmed death receptor 1, and soluble CD25 in Sokal high risk chronic myeloid leukemia. PLoS One 2013; 8:e55818. [PMID: 23383287 PMCID: PMC3561335 DOI: 10.1371/journal.pone.0055818] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 01/02/2013] [Indexed: 12/16/2022] Open
Abstract
Immunotherapy (eg interferon α) in combination with tyrosine kinase inhibitors is currently in clinical trials for treatment of chronic myeloid leukemia (CML). Cancer patients commonly have problems with so called immune escape mechanisms that may hamper immunotherapy. Hence, to study the function of the immune system in CML is of interest. In the present paper we have identified immune escape mechanisms in CML with focus on those that directly hamper T cells since these cells are important to control tumor progression. CML patient samples were investigated for the presence of myeloid-derived suppressor cells (MDSCs), expression of programmed death receptor ligand 1/programmed death receptor 1 (PD-L1/PD-1), arginase 1 and soluble CD25. MDSC levels were increased in samples from Sokal high risk patients (p<0,05) and the cells were present on both CD34 negative and CD34 positive cell populations. Furthermore, expression of the MDSC-associated molecule arginase 1, known to inhibit T cells, was increased in the patients (p = 0,0079). Myeloid cells upregulated PD-L1 (p<0,05) and the receptor PD-1 was present on T cells. However, PD-L1 blockade did not increase T cell proliferation but upregulated IL-2 secretion. Finally, soluble CD25 was increased in high risk patients (p<0,0001). In conclusion T cells in CML patients may be under the control of different immune escape mechanisms that could hamper the use of immunotherapy in these patients. These escape mechanisms should be monitored in trials to understand their importance and how to overcome the immune suppression.
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