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1.
Trials ; 22(1): 595, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488845

RESUMO

BACKGROUND: Chronic lower limb ischemia develops earlier and more frequently in patients with type 2 diabetes mellitus. Diabetes remains the main cause of lower-extremity non-traumatic amputations. Current medical treatment, based on antiplatelet therapy and statins, has demonstrated deficient improvement of the disease. In recent years, research has shown that it is possible to improve tissue perfusion through therapeutic angiogenesis. Both in animal models and humans, it has been shown that cell therapy can induce therapeutic angiogenesis, making mesenchymal stromal cell-based therapy one of the most promising therapeutic alternatives. The aim of this study is to evaluate the feasibility, safety, and efficacy of cell therapy based on mesenchymal stromal cells derived from adipose tissue intramuscular administration to patients with type 2 diabetes mellitus with critical limb ischemia and without possibility of revascularization. METHODS: A multicenter, randomized double-blind, placebo-controlled trial has been designed. Ninety eligible patients will be randomly assigned at a ratio 1:1:1 to one of the following: control group (n = 30), low-cell dose treatment group (n = 30), and high-cell dose treatment group (n = 30). Treatment will be administered in a single-dose way and patients will be followed for 12 months. Primary outcome (safety) will be evaluated by measuring the rate of adverse events within the study period. Secondary outcomes (efficacy) will be measured by assessing clinical, analytical, and imaging-test parameters. Tertiary outcome (quality of life) will be evaluated with SF-12 and VascuQol-6 scales. DISCUSSION: Chronic lower limb ischemia has limited therapeutic options and constitutes a public health problem in both developed and underdeveloped countries. Given that the current treatment is not established in daily clinical practice, it is essential to provide evidence-based data that allow taking a step forward in its clinical development. Also, the multidisciplinary coordination exercise needed to develop this clinical trial protocol will undoubtfully be useful to conduct academic clinical trials in the field of cell therapy in the near future. TRIAL REGISTRATION: ClinicalTrials.gov NCT04466007 . Registered on January 07, 2020. All items from the World Health Organization Trial Registration Data Set are included within the body of the protocol.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Mesenquimais , Noma , Tecido Adiposo , Animais , Ensaios Clínicos Fase II como Assunto , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Método Duplo-Cego , Humanos , Isquemia/diagnóstico , Isquemia/terapia , Estudos Multicêntricos como Assunto , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Resultado do Tratamento
2.
CRISPR J ; 4(4): 519-535, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34406033

RESUMO

Chronic myeloid leukemia (CML) is a hematopoietic malignancy produced by a unique oncogenic event involving the constitutively active tyrosine-kinase (TK) BCR/ABL1. TK inhibitors (TKI) changed its prognosis and natural history. Unfortunately, ABL1 remains unaffected by TKIs. Leukemic stem cells (LSCs) remain, and resistant mutations arise during treatment. To address this problem, we have designed a therapeutic CRISPR-Cas9 deletion system targeting BCR/ABL1. The system was efficiently electroporated to cell lines, LSCs from a CML murine model, and LSCs from CML patients at diagnosis, generating a specific ABL1 null mutation at high efficiency and allowing the edited leukemic cells to be detected and tracked. The CRISPR-Cas9 deletion system triggered cell proliferation arrest and apoptosis in murine and human CML cell lines. Patient and murine-derived xenografts with CRISPR-edited LSCs in NOD SCID gamma niches revealed that normal multipotency and repopulation ability of CRISPR edited LSCs were fully restored. Normal hematopoiesis was restored, avoiding myeloid bias. To the best of our knowledge, we show for the first time how a CRISPR-Cas9 deletion system efficiently interrupts BCR/ABL1 oncogene in primary LSCs to bestow a therapeutic benefit. This study is a proof of concept for genome editing in all those diseases, like CML, sustained by a single oncogenic event, opening up new therapeutic opportunities.

3.
Stem Cell Res Ther ; 12(1): 451, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34380565

RESUMO

BACKGROUND: Polytrauma is a major clinical problem due to its impact on morbidity and mortality, especially among the younger population. Its pathophysiology is not completely elucidated, and the study of the involvement of certain cell populations with therapeutic potential, such as mesenchymal stromal cells (MSCs), is an area of growing interest, as mesenchymal cells have anti-inflammatory, immunoregulatory, and osteogenic potential. METHODS: In the present preliminary work, we have evaluated the characteristics of MSCs in terms of proliferation, immunophenotype, cell cycle, clonogenic capacity, and multilineage differentiation ability in a series of 18 patients with polytrauma and compared them to those from otherwise healthy patients undergoing elective spinal surgery. RESULTS: MSCs from polytrauma patients displayed higher proliferative potential with significantly higher cumulative population doublings, increased expression of some important cell adhesion molecules (CD105, CD166), and an early pre-osteogenic differentiation ability compared to those of the control group. CONCLUSIONS: MSCs could potentially be of help in the repair process of polytrauma patients contribute to both cell-tissue repair and anti-inflammatory response. This potential should be further explored in larger studies.


Assuntos
Células-Tronco Mesenquimais , Traumatismo Múltiplo , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Osteogênese
5.
Stem Cells ; 39(1): 26-32, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32985054

RESUMO

The therapeutic effects of mesenchymal stromal cells (MSCs) in graft failure or poor graft function after allogenic hematopoietic stem cell transplantation (HSCT) are currently undergoing clinical evaluation. MSCs exert their functions, at least partially, through the secretion of extracellular vesicles (MSC-EVs). The available information on the biological potential of MSC-EVs to improve hematopoietic function, both in in vitro studies and in reported preclinical models, focusing on the possible mechanisms of these effects are summarized in the current review. The potential advantages of EVs over MSCs are also discussed, as well as the limitations and uncertainties in terms of isolation, characterization, mechanism of action in this setting, and industrial scalability that should be addressed for their potential clinical application.

7.
Front Med (Lausanne) ; 7: 462, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32984363

RESUMO

The University Hospital of Salamanca, in Spain, had its first COVID-19 case on March 1st and as of May 11th, we had 1,100 positive cases. Based on the vulnerability of patients with blood cancers, on March 9th, the Hematology Department developed a protocol, amended as the new information was available, to maintain the Hematology Unit as a "free COVID-19 island." The protocol included symptom-based surveys and screening tests to patients, caregivers, and healthcare personnel to identify early potential positive cases and prevent its spread. Between March 9 and April 28, 32 asymptomatic patients and caregivers were tested and 68 rT-PCR diagnostic assays have been performed with two positive results. A 106 healthcare workers have been tested (208 rT-PCR) and seven of them were positive. In summary, the implementation of preemptive measures after the first case appeared allowed us to be able to provide treatment to our patients.

8.
J Transl Med ; 18(1): 356, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948200

RESUMO

BACKGROUND: Mesenchymal stromal cells are a safe and promising option to treat knee osteoarthritis as previously demonstrated in different clinical trials. However, their efficacy, optimal dose and addition of adjuvants must be determined. Here, we evaluated the clinical effects of a dose of 100 × 106 bone marrow mesenchymal stromal cells (BM-MSCs) in combination with Platelet Rich Plasma (PRGF®) as adjuvant in a randomized clinical trial. METHODS: A phase II, multicenter, randomized clinical trial with active control was conducted. Sixty patients diagnosed with knee OA were randomly assigned to 3 weekly doses of PRGF® or intraarticular administration of 100 × 106 cultured autologous BM-MSCs plus PRGF®. Patients were followed up for 12 months, and pain and function were assessed using VAS and WOMAC and by measuring the knee range of motion range. X-ray and magnetic resonance imaging analyses were performed to analyze joint damage. RESULTS: No adverse effects were reported after BM-MSC administration or during follow-up. According to VAS, the mean value (SD) for PRGF® and BM-MSC with PRGF® went from 5 (1.8) to 4.5 (2.2) (p = 0.389) and from 5.3 (1.9) to 3.5 (2.5) (p = 0.01), respectively at 12 months. In WOMAC, the mean (SD) baseline and 12-month overall WOMAC scores in patients treated with PRGF® was 31.9 (16.2) and 22.3 (15.8) respectively (p = 0.002) while that for patients treated with BM-MSC plus PRGF® was 33.4 (18.7) and 23.0 (16.6) (p = 0.053). Although statistical significances between groups have been not detected, only patients being treated with BM-MSC plus PRGF® could be considered as a OA treatment responders following OARSI criteria. X-ray and MRI (WORMS protocol) revealed no changes in knee joint space width or joint damage. CONCLUSIONS: Treatment with BM-MSC associated with PRGF® was shown to be a viable therapeutic option for osteoarthritis of the knee, with clinical improvement at the end of follow-up. Further phase III clinical trials would be necessary to confirm the efficacy. Trial registration Clinical Trials.gov identifier NCT02365142. Nº EudraCT: 2011-006036-23.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Osteoartrite do Joelho , Plasma Rico em Plaquetas , Humanos , Injeções Intra-Articulares , Osteoartrite do Joelho/terapia , Resultado do Tratamento
9.
EClinicalMedicine ; 25: 100454, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32838232

RESUMO

Background: Identification of effective treatments in severe cases of COVID-19 requiring mechanical ventilation represents an unmet medical need. Our aim was to determine whether the administration of adipose-tissue derived mesenchymal stromal cells (AT-MSC) is safe and potentially useful in these patients. Methods: Thirteen COVID-19 adult patients under invasive mechanical ventilation who had received previous antiviral and/or anti-inflammatory treatments (including steroids, lopinavir/ritonavir, hydroxychloroquine and/or tocilizumab, among others) were treated with allogeneic AT-MSC. Ten patients received two doses, with the second dose administered a median of 3 days (interquartile range-IQR- 1 day) after the first one. Two patients received a single dose and another patient received 3 doses. Median number of cells per dose was 0.98 × 106 (IQR 0.50 × 106) AT-MSC/kg of recipient's body weight. Potential adverse effects related to cell infusion and clinical outcome were assessed. Additional parameters analyzed included changes in imaging, analytical and inflammatory parameters. Findings: First dose of AT-MSC was administered at a median of 7 days (IQR 12 days) after mechanical ventilation. No adverse events were related to cell therapy. With a median follow-up of 16 days (IQR 9 days) after the first dose, clinical improvement was observed in nine patients (70%). Seven patients were extubated and discharged from ICU while four patients remained intubated (two with an improvement in their ventilatory and radiological parameters and two in stable condition). Two patients died (one due to massive gastrointestinal bleeding unrelated to MSC therapy). Treatment with AT-MSC was followed by a decrease in inflammatory parameters (reduction in C-reactive protein, IL-6, ferritin, LDH and d-dimer) as well as an increase in lymphocytes, particularly in those patients with clinical improvement. Interpretation: Treatment with intravenous administration of AT-MSC in 13 severe COVID-19 pneumonia under mechanical ventilation in a small case series did not induce significant adverse events and was followed by clinical and biological improvement in most subjects. Funding: None.

10.
Biol Blood Marrow Transplant ; 26(12): 2237-2244, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32717433

RESUMO

Accurate prognostic tools are crucial to assess the risk/benefit ratio of allogeneic hematopoietic cell transplantation (allo-HCT) in patients with myelofibrosis (MF). We aimed to evaluate the performance of the Myelofibrosis Transplant Scoring System (MTSS) and identify risk factors for survival in a multicenter series of 197 patients with MF undergoing allo-HCT. After a median follow-up of 3.1 years, 47% of patients had died, and the estimated 5-year survival rate was 51%. Projected 5-year risk of nonrelapse mortality and relapse incidence was 30% and 20%, respectively. Factors independently associated with increased mortality were a hematopoietic cell transplantation-specific comorbidity index (HCT-CI) ≥3 and receiving a graft from an HLA-mismatched unrelated donor or cord blood, whereas post-transplant cyclophosphamide (PT-Cy) was associated with improved survival. Donor type was the only parameter included in the MTSS model with independent prognostic value for survival. According to the MTSS, 3-year survival was 62%, 66%, 37%, and 17% for low-, intermediate-, high-, and very high-risk groups, respectively. By pooling together the low- and intermediate-risk groups, as well as the high- and very high-risk groups, we pinpointed 2 categories: standard risk and high risk (25% of the series). Three-year survival was 62% in standard-risk and 25% in high-risk categories (P < .001). We derived a risk score based on the 3 independent risk factors for survival in our series (donor type, HCT-CI, and PT-Cy). The corresponding 5-year survival for the low-, intermediate-, and high-risk categories was 79%, 55%, and 32%, respectively (P < .001). In conclusion, the MTSS model failed to clearly delineate 4 prognostic groups in our series but may still be useful to identify a subset of patients with poor outcome. We provide a simple prognostic scoring system for risk/benefit considerations before transplantation in patients with MF.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mielofibrose Primária , Humanos , Mielofibrose Primária/terapia , Prognóstico , Condicionamento Pré-Transplante , Transplante Homólogo , Resultado do Tratamento
11.
J Mol Diagn ; 22(10): 1217-1224, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32688056

RESUMO

Molecular monitoring of BCR-ABL1 transcripts is a critical prognostic indicator of treatment response in chronic myeloid leukemia (CML). Quantification of BCR-ABL1 transcripts using ABL1 or GUSB as control genes on the early molecular response (MR) to frontline nilotinib was studied using data from 60 patients with chronic-phase CML from the Evaluating Nilotinib Efficacy and Safety in Clinical Trials as First-Line Treatment (ENEST1st) substudy. Effects of BCR-ABL1/ABL1 and BCR-ABL1/GUSB ratios at early time points as independent variables on subsequent MR were determined by logistic regression analyses and predictive cut-off values determined by receiver operating curve analyses. From day 45, concordance was found for both control genes' early transcript kinetics and ability to predict subsequent deep MR at 18 months. From baseline to 3 months, transcripts descended linearly with both control genes. Use of ABL1 allowed for an earlier prediction (2 months) of subsequent MR than with GUSB (3 months), with cut-off values of 1.5% and 0.19%, respectively. The dynamic determination of BCR-ABL1 transcripts using either internal control gene is valid and predictive of subsequent MR. The use of GUSB to predict an earlier and more accurate response than ABL1 is not supported in the results. Accurate early indicators of MR are essential to identify patients likely to have inferior outcomes who may benefit from treatment with an alternative tyrosine kinase inhibitor.

12.
Biomolecules ; 10(4)2020 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-32260546

RESUMO

Mesenchymal Stromal Cells (MSC) are multipotent cells characterized by self-renewal, multilineage differentiation, and immunomodulatory properties. To obtain a gene regulatory profile of human MSCs, we generated a compendium of more than two hundred cell samples with genome-wide expression data, including a homogeneous set of 93 samples of five related primary cell types: bone marrow mesenchymal stem cells (BM-MSC), hematopoietic stem cells (HSC), lymphocytes (LYM), fibroblasts (FIB), and osteoblasts (OSTB). All these samples were integrated to generate a regulatory gene network using the algorithm ARACNe (Algorithm for the Reconstruction of Accurate Cellular Networks; based on mutual information), that finds regulons (groups of target genes regulated by transcription factors) and regulators (i.e., transcription factors, TFs). Furtherly, the algorithm VIPER (Algorithm for Virtual Inference of Protein-activity by Enriched Regulon analysis) was used to inference protein activity and to identify the most significant TF regulators, which control the expression profile of the studied cells. Applying these algorithms, a footprint of candidate master regulators of BM-MSCs was defined, including the genes EPAS1, NFE2L1, SNAI2, STAB2, TEAD1, and TULP3, that presented consistent upregulation and hypomethylation in BM-MSCs. These TFs regulate the activation of the genes in the bone marrow MSC lineage and are involved in development, morphogenesis, cell differentiation, regulation of cell adhesion, and cell structure.


Assuntos
Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Células-Tronco Mesenquimais/metabolismo , Genômica , Humanos
13.
Antioxidants (Basel) ; 9(1)2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952182

RESUMO

Chronic myeloid leukemia (CML) is characterized by the expression of the oncogenic kinase BCR-ABL. Although tyrosine kinase inhibitors (TKIs) against BCR-ABL represent the standard therapeutic option for CML, resistances to TKIs can be a serious problem. Thus, the search for novel therapeutic approaches is still needed. CML cells show an increased ROS production, which is required for maintaining the BCR-ABL signaling cascade active. In line with that, reducing ROS levels could be an interesting therapeutic strategy for the clinical management of resistant CML. To analyze the therapeutic potential of xanthine oxidoreductase (XOR) in CML, we tested the effect of XOR inhibitor allopurinol. Here, we show for the first time the therapeutic potential of allopurinol against BCR-ABL-positive CML cells. Allopurinol reduces the proliferation and clonogenic ability of the CML model cell lines K562 and KCL22. More importantly, the combination of allopurinol with imatinib or nilotinib reduced cell proliferation in a synergistic manner. Moreover, the co-treatment arms hampered cell clonogenic capacity and induced cell death more strongly than each single-agent arm. The reduction of intracellular ROS levels and the attenuation of the BCR-ABL signaling cascade may explain these effects. Finally, the self-renewal potential of primary bone marrow cells from CML patients was also severely reduced especially by the combination of allopurinol with TKIs. In summary, here we show that XOR inhibition is an interesting therapeutic option for CML, which can enhance the effectiveness of the TKIs currently used in clinics.

14.
Bone Marrow Transplant ; 55(4): 681-694, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31636397

RESUMO

In many healthcare settings, benchmarking for complex procedures has become a mandatory requirement by competent authorities, regulators, payers and patients to assure clinical performance, cost-effectiveness and safe care of patients. In several countries inside and outside Europe, benchmarking systems have been established for haematopoietic stem cell transplantation (HSCT), but access is not universal. As benchmarking is now integrated into the FACT-JACIE standards, the EBMT and JACIE established a Clinical Outcomes Group (COG) to develop and introduce a universal system accessible across EBMT members. Established systems from seven European countries (United Kingdom, Italy, Belgium, France, Germany, Spain, Switzerland), USA and Australia were appraised, revealing similarities in process, but wide variations in selection criteria and statistical methods. In tandem, the COG developed the first phase of a bespoke risk-adapted international benchmarking model for one-year survival following allogeneic and autologous HSCT based on current capabilities within the EBMT registry core dataset. Data completeness, which has a critical impact on validity of centre comparisons, is also assessed. Ongoing development will include further scientific validation of the model, incorporation of further variables (when appropriate) alongside implementation of systems for clinically meaningful interpretation and governance aiming to maximise acceptance to centres, clinicians, payers and patients across EBMT.


Assuntos
Benchmarking , Transplante de Células-Tronco Hematopoéticas , Acreditação , Austrália , Bélgica , Medula Óssea , Europa (Continente) , França , Alemanha , Humanos , Itália , Espanha , Suíça , Reino Unido
15.
Cytotherapy ; 22(1): 1-5, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31866320

RESUMO

In the current article we summarize the 15-year experience of the Spanish Cell Therapy Network (TerCel), a successful collaborative public initiative funded by the Spanish government for the support of nationwide translational research in this important area. Thirty-two research groups organized in three programs devoted to cardiovascular, neurodegenerative and immune-inflammatory diseases, respectively, currently form the network. Each program has three working packages focused on basic science, pre-clinical studies and clinical application. TerCel has contributed during this period to boost the translational research in cell therapy in Spain, setting up a network of Good Manufacturing Practice-certified cell manufacturing facilities- and increasing the number of translational research projects, publications, patents and clinical trials of the participating groups, especially those in collaboration. TerCel pays particular attention to the public-private collaboration, which, for instance, has led to the development of the first allogeneic cell therapy product approved by the European Medicines Agency, Darvadstrocel. The current collaborative work is focused on the development of multicenter phase 2 and 3 trials that could translate these therapies to clinical practice for the benefit of patients.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Medicina Regenerativa/métodos , Pesquisa Médica Translacional/métodos , Pesquisa Biomédica , Doenças Cardiovasculares/terapia , Humanos , Doenças do Sistema Imunitário/terapia , Colaboração Intersetorial , Doenças Neurodegenerativas/terapia , Espanha
16.
Stem Cells Transl Med ; 9(3): 295-301, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31886629

RESUMO

The aim of this clinical trial (ID Number NCT01803347) was to determine the safety and efficacy of autologous adipose-derived stem cells (ASCs) for treatment of cryptoglandular fistula. This research was conducted following an analysis of the mistakes of a same previous phase III clinical trial. We designed a multicenter, randomized, single-blind clinical trial, recruiting 57 patients. Forty-four patients were categorized as belonging to the intent-to-treat group. Of these, 23 patients received 100 million ASCs plus intralesional fibrin glue (group A) and 21 received intralesional fibrin glue (group B), both after a deeper curettage of tracks and closure of internal openings. Fistula healing was defined as complete re-epithelialization of external openings. Those patients in whom the fistula had not healed after 16 weeks were eligible for retreatment. Patients were evaluated at 1, 4, 16, 36, and 52 weeks and 2 years after treatment. Results were assessed by an evaluator blinded to the type of treatment. After 16 weeks, the healing rate was 30.4% in group A and 42.8% in group B, rising to 55.0% and 63.1%, respectively, at 52 weeks. At the end of the study (2 years after treatment), the healing rate remained at 50.0% in group A and had reduced to 26.3% in group B. The safety of the cellular treatment was confirmed and no impact on fecal continence was detected. The main conclusion was that autologous ASCs for the treatment of cryptoglandular perianal fistula is safe and can favor long-term and sustained fistula healing.

17.
Haematologica ; 105(2): 297-316, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31753925

RESUMO

Chimeric antigen receptor (CAR) T cells are a novel class of anti-cancer therapy in which autologous or allogeneic T cells are engineered to express a CAR targeting a membrane antigen. In Europe, tisagenlecleucel (Kymriah™) is approved for the treatment of refractory/relapsed acute lymphoblastic leukemia in children and young adults as well as relapsed/refractory diffuse large B-cell lymphoma, while axicabtagene ciloleucel (Yescarta™) is approved for the treatment of relapsed/refractory high-grade B-cell lymphoma and primary mediastinal B-cell lymphoma. Both agents are genetically engineered autologous T cells targeting CD19. These practical recommendations, prepared under the auspices of the European Society of Blood and Marrow Transplantation, relate to patient care and supply chain management under the following headings: patient eligibility, screening laboratory tests and imaging and work-up prior to leukapheresis, how to perform leukapheresis, bridging therapy, lymphodepleting conditioning, product receipt and thawing, infusion of CAR T cells, short-term complications including cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome, antibiotic prophylaxis, medium-term complications including cytopenias and B-cell aplasia, nursing and psychological support for patients, long-term follow-up, post-authorization safety surveillance, and regulatory issues. These recommendations are not prescriptive and are intended as guidance in the use of this novel therapeutic class.


Assuntos
Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Antígenos CD19 , Medula Óssea , Terapia Baseada em Transplante de Células e Tecidos , Criança , Europa (Continente) , Humanos , Receptores de Antígenos de Linfócitos T/genética , Adulto Jovem
19.
Front Pharmacol ; 10: 1340, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824308

RESUMO

Introduction: Dasatinib is a dual SRC/ABL tyrosine kinase inhibitor used to treat chronic myeloid leukemia (CML) that is known to have unique immunomodulatory effects. In particular, dasatinib intake typically causes lymphocytosis, which has been linked to better clinical response. Since the underlying mechanisms are unknown and SRC family kinases are involved in many cell motility processes, we hypothesized that the movement and migration of lymphocytes is modulated by dasatinib. Patients, Materials and Methods: Peripheral blood samples from CML patients treated with second-line dasatinib were collected before and 2 h after the first dasatinib intake, and follow-up samples from the same patients 3 and 6 months after the start of therapy. The migratory capacity and phenotype of lymphocytes and differential blood counts before and after drug intake were compared for all study time-points. Results: We report here for the first time that dasatinib intake is associated with inhibition of peripheral blood T-cell migration toward the homeostatic chemokines CCL19 and CCL21, which control the trafficking toward secondary lymphoid organs, mainly the lymph nodes. Accordingly, the proportion of lymphocytes in blood expressing CCR7, the chemokine receptor for both CCL19 and CCL21, decreased after the intake including both naïve CD45RA+ and central memory CD45RO+ T-cells. Similarly, naïve B-cells diminished with dasatinib. Finally, such changes in the migratory patterns did not occur in those patients whose lymphocyte counts remained unchanged after taking the drug. Discussion: We, therefore, conclude that lymphocytosis induced by dasatinib reflects a pronounced redistribution of naïve and memory populations of all lymphocyte subsets including CD4+ and CD8+ T-cells and B-cells.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31781552

RESUMO

The potent immunomodulatory activities displayed by mesenchymal stromal cells (MSCs) have motivated their application in hundreds of clinical trials to date. In some countries, they have subsequently been approved for the treatment of immune disorders such as Crohn's disease and graft-versus-host disease. Increasing evidence suggests that their main mechanism of action in vivo relies on paracrine signaling and extracellular vesicles. Mesenchymal stromal cell-derived extracellular vesicles (MSC-EVs) play a prominent role in intercellular communication by allowing the horizontal transfer of microRNAs, mRNAs, proteins, lipids and other bioactive molecules between MSCs and their targets. However, despite the considerable momentum gained by MSC-EV research, the precise mechanism by which MSC-EVs interact with the immune system is still debated. Available evidence is highly context-dependent and fragmentary, with a limited number of reports trying to link their efficacy to specific active components shuttled within them. In this concise review, currently available evidence on the molecular mechanisms underlying the effects of MSC-EV cargo on the immune system is analyzed. Studies that pinpoint specific MSC-EV-borne mediators of immunomodulation are highlighted, with a focus on the signaling events triggered by MSC-EVs in target immune cells. Reports that study the effects of preconditioning or "licensing" in MSC-EV-mediated immunomodulation are also presented. The need for further studies that dissect the mechanisms of MSC-EV cargo in the adaptive immune system is emphasized. Finally, the major challenges that need to be addressed to harness the full potential of these signaling vehicles are discussed, with the ultimate goal of effectively translating MSC-EV treatments into the clinic.

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