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2.
Artigo em Inglês | MEDLINE | ID: mdl-37970762

RESUMO

OBJECTIVES: Timely and accurate preoperative diagnosis of uterine sarcoma will increase patient survival. The primary aim of this study was to describe the ultrasound features of uterine sarcoma compared with those of uterine leiomyoma based on the terms and definitions of the Morphological Uterus Sonographic Assessment (MUSA) group. A secondary aim was to assess the interobserver agreement for reporting on ultrasound features according to MUSA terminology. METHODS: This was a retrospective cohort study of patients with uterine sarcoma or uterine leiomyoma treated in a single tertiary center during the periods 1997-2019 and 2016-2019, respectively. Demographic characteristics, presenting symptoms and surgical outcomes were extracted from patients' files. Ultrasound images were re-evaluated independently by two sonologists using MUSA terms and definitions. Descriptive statistics were calculated and interobserver agreement was assessed using Cohen's κ (with squared weights) or intraclass correlation coefficient, as appropriate. RESULTS: A total of 107 patients were included, of whom 16 had a uterine sarcoma and 91 had a uterine leiomyoma. Abnormal uterine bleeding was the most frequent presenting symptom (69/107 (64%)). Compared with leiomyoma cases, patients with uterine sarcoma were older (median age, 65 (interquartile range (IQR), 60-70) years vs 48 (IQR, 43-52) years) and more likely to be postmenopausal (13/16 (81%) vs 15/91 (16%)). In the uterine sarcoma cohort, leiomyosarcoma was the most frequent histological type (6/16 (38%)), followed by adenosarcoma (4/16 (25%)). On ultrasound evaluation, according to Observers 1 and 2, the tumor border was irregular in most sarcomas (11/16 (69%) and 13/16 (81%) cases, respectively), but regular in most leiomyomas (65/91 (71%) and 82/91 (90%) cases, respectively). Lesion echogenicity was classified as non-uniform in 68/91 (75%) and 51/91 (56%) leiomyomas by Observers 1 and 2, respectively, and 15/16 (94%) uterine sarcomas by both observers. More than 60% of the uterine sarcomas showed acoustic shadows (11/16 (69%) and 10/16 (63%) cases by Observers 1 and 2, respectively), whereas calcifications were reported in a small minority (0/16 (0%) and 2/16 (13%) cases by Observers 1 and 2, respectively). In uterine sarcomas, intralesional vascularity was reported as moderate to abundant in 13/16 (81%) cases by Observer 1 and 15/16 (94%) cases by Observer 2, while circumferential vascularity was scored as moderate to abundant in 6/16 (38%) by both observers. Interobserver agreement for the presence of cystic areas, calcifications, acoustic shadow, central necrosis, color score (overall, intralesional and circumferential) and maximum diameter of the lesion was moderate. The agreement for shape of lesion, tumor border and echogenicity was fair. CONCLUSIONS: A postmenopausal patient presenting with abnormal uterine bleeding and a new or growing mesenchymal mass with irregular tumor borders, moderate-to-abundant intralesional vascularity, cystic areas and an absence of calcifications on ultrasonography is at a higher risk of having a uterine sarcoma. Interobserver agreement for most MUSA terms and definitions is moderate. Future studies should validate the abovementioned clinical and ultrasound findings on uterine mesenchymal tumors in a prospective multicenter fashion. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

3.
Ultrasound Obstet Gynecol ; 60(2): 277-283, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35195311

RESUMO

Measuring vascularization in uterine fibroids is important for their diagnosis, treatment and prognosis. Vascularization can be measured by power Doppler ultrasound. The power Doppler signal depends on fibroid characteristics and on a variety of ultrasound-machine settings. Literature describing which machine settings influence the power Doppler signal is limited. Each manufacturer names settings and presets at their own discretion, with little information available publicly. Consistency of machine settings is important for correct interpretation of images in daily practice and is essential in yielding reproducible data for research. The aims of this paper, drawing from both a literature search and semistructured interviews with ultrasound-machine engineers and clinical experts in gynecological ultrasound, were: (1) to provide comprehensive background information on ultrasound physics and fibroid characteristics; (2) to present an overview of machine settings relevant to both two- and three-dimensional power Doppler, including power Doppler frequency, pulse repetition frequency, gain, wall-motion filter, acoustic power, persistence and signal rise; and (3) to provide a step-by-step tutorial on the optimal settings for vascular evaluation of uterine fibroids using power Doppler. The step-by-step tutorial comprises six steps to optimize the power Doppler signal, create a preset and acquire a reliable three-dimensional volume. This step-by-step tutorial should help research groups and clinicians to use power Doppler correctly and reproducibly in the evaluation of uterine fibroids. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Imageamento Tridimensional , Leiomioma , Humanos , Imageamento Tridimensional/métodos , Leiomioma/diagnóstico por imagem , Neovascularização Patológica , Ultrassonografia , Ultrassonografia Doppler/métodos
4.
Ultrasound Obstet Gynecol ; 60(1): 118-131, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34587658

RESUMO

OBJECTIVES: To evaluate whether the Morphological Uterus Sonographic Assessment (MUSA) features of adenomyosis need to be better defined and, if deemed necessary, to reach consensus on the updated definitions. METHODS: A modified Delphi procedure was performed among European gynecologists with expertise in ultrasound diagnosis of adenomyosis. To identify MUSA features that might need revision, 15 two-dimensional (2D) video recordings (four recordings also included three-dimensional (3D) still images) of transvaginal ultrasound (TVS) examinations of the uterus were presented in the first Delphi round (online questionnaire). Experts were asked to confirm or refute the presence of each of the nine MUSA features of adenomyosis (described in the original MUSA consensus statement) in each of the 15 videoclips and to provide comments. In the second Delphi round (online questionnaire), the results of the first round and suggestions for revision of MUSA features were shared with the experts before they were asked to assess a new set of 2D and 3D still images of TVS examinations and to provide feedback on the proposed revisions. A third Delphi round (virtual group meeting) was conducted to discuss and reach final consensus on revised definitions of MUSA features. Consensus was predefined as at least 66.7% agreement between experts. RESULTS: Of 18 invited experts, 16 agreed to participate in the Delphi procedure. Eleven experts completed and four experts partly finished the first round. The experts identified a need for more detailed definitions of some MUSA features. They recommended use of 3D ultrasound to optimize visualization of the junctional zone. Fifteen experts participated in the second round and reached consensus on the presence or absence of ultrasound features of adenomyosis in most of the still images. Consensus was reached for all revised definitions except those for subendometrial lines and buds and interrupted junctional zone. Thirteen experts joined the online meeting, in which they discussed and agreed on final revisions of the MUSA definitions. There was consensus on the need to distinguish between direct features of adenomyosis, i.e. features indicating presence of ectopic endometrial tissue in the myometrium, and indirect features, i.e. features reflecting changes in the myometrium secondary to presence of endometrial tissue in the myometrium. Myometrial cysts, hyperechogenic islands and echogenic subendometrial lines and buds were classified unanimously as direct features of adenomyosis. Globular uterus, asymmetrical myometrial thickening, fan-shaped shadowing, translesional vascularity, irregular junctional zone and interrupted junctional zone were classified as indirect features of adenomyosis. CONCLUSION: Consensus between gynecologists with expertise in ultrasound diagnosis of adenomyosis was achieved regarding revised definitions of the MUSA features of adenomyosis and on the classification of MUSA features as direct or indirect signs of adenomyosis. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Adenomiose , Musa , Adenomiose/diagnóstico por imagem , Técnica Delphi , Feminino , Humanos , Miométrio/diagnóstico por imagem , Gravidez , Ultrassonografia/métodos , Útero/diagnóstico por imagem
6.
Facts Views Vis Obgyn ; 6(4): 177-83, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25593692

RESUMO

INTRODUCTION: Today, perinatal audit focuses basically on cases of perinatal mortality. In most centres in Western Europe, perinatal mortality is low. Identification of metabolic acidosis at birth may increase index cases eligible for evaluation of perinatal care, and this might improve quality of perinatal audit. The aim of this study is to assess the incidence of metabolic acidosis at birth in order to estimate its impact on perinatal audit. PATIENTS AND METHODS: Cord blood was analysed for every neonate born between January 1, 2010 and December 31, 2012 in Ziekenhuis Oost-Limburg, Genk. Acidosis was defined as an umbilical arterial pH ≤ 7.05 with or without a venous pH ≤ 7.17. Respiratory acidosis (RA) was defined as acidosis with normal base excess, and metabolic acidosis (MA) was defined as acidosis with an arterial or venous base excess ≤ -10 mmol/L. In case of failed cord blood sampling, 5 minute Apgar score ≤ 6 was considered as the clinical equivalent of MA. Retrospective chart review of obstetric and paediatric files was performed for all cases of MA, together with review of paediatric follow-up charts from at least 6 months after birth. Perinatal asphyxia was defined as biochemical evidence for MA at birth, associated with early onset neonatal encephalopathy and long-term symptoms of cerebral palsy. RESULTS: In a total of 6614 babies, perinatal death up to 7 days of life occurred in 40 babies (6.0‰). Acidosis was present in 183 neonates (2.8%), of which 130 (2.0%) had RA and 53 (0.8%) had MA. Of the 173 neonates with unknown pH values, 6 had Apgar scores ≤ 6. Of 59 babies born with MA or its clinical equivalent, 52 (88.1%) showed no neurologic symptoms at birth. Two (3.4%) died in the early neonatal period, one after abruptio placentae and one due to chorioamnionitis and severe prematurity. Five (8.5%) MA babies had symptoms of early onset neonatal encephalopathy, which recovered in three (5.1%), and persisted long-term in two others (3.4%). The two babies with cerebral palsy (prevalence 1/3300) were both born after instrumental vaginal delivery for foetal distress. CONCLUSION: In our study cohort, the incidence of perinatal mortality is 6‰. The incidence of metabolic acidosis is 9‰. Addition of cases of metabolic acidosis to those of mortality doubles index cases eligible for perinatal audit. The incidence of babies surviving with cerebral palsy after metabolic acidosis at birth is very low (0.3‰). Our results suggest that instrumental delivery for foetal distress might be a risk factor for metabolic acidosis with persisting neurologic dysfunction. Our study illustrates that identification of peripartum near-miss is useful for perinatal audit.

7.
Leukemia ; 23(12): 2281-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19710697

RESUMO

Epigenetic code modifications by histone deacetylase inhibitors have recently been proposed as potential new therapies for hematological malignancies. Chronic lymphocytic leukemia (CLL) remains incurable despite the introduction of new treatments. CLL B cells are characterized by an apoptosis defect rather than excessive proliferation, but proliferation centers have been found in organs such as the bone marrow and lymph nodes. In this study, we analyzed gene expression modifications in CLL B cells after treatment with valproic acid (VPA), a well-tolerated anti-epileptic drug with HDAC inhibitory activity. CLL B cells obtained from 14 patients were treated in vitro with a concentration of 1 mM VPA for 4 h. VPA effects on gene expression were thereafter studied using Affymetrix technology, and some identified genes were validated by real-time PCR and western blot. We observed that VPA induced apoptosis by downregulating several anti-apoptotic genes and by upregulating pro-apoptotic genes. Furthermore, VPA significantly increased chemosensitivity to fludarabine, flavopiridol, bortezomib, thalidomide and lenalidomide. VPA inhibited the proliferation of CpG/IL2-stimulated CLL B cells and modulated many cell cycle messenger RNAs. In conclusion, exposure of CLL B cells to VPA induced apoptosis, potentiated chemotherapeutic agent effects and inhibited proliferation. These data strongly suggest the use of VPA in CLL treatment, particularly in combination with antileukemia agents.


Assuntos
Perfilação da Expressão Gênica/métodos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B/patologia , Ácido Valproico/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Inibidores de Histona Desacetilases/farmacologia , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Análise de Sequência com Séries de Oligonucleotídeos
8.
Cytotherapy ; 7(6): 470-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16306008

RESUMO

BACKGROUND: Infusion of ex vivo differentiated myeloid progenitors may reduce or abrogate severe neutropenia following mobilized peripheral blood transplantation. We compared the ex vivo expansion of myeloid progenitor cells starting from cancer patients (CP) and from normal donors (ND) and evaluated the influence of the CD34(+) cell mobilization on the capacities of cells to be expanded. METHODS: The ex vivo-expanded cells were evaluated for their phenotype, the presence of primary and secondary granules and their functional capacities (oxidative burst activity and phagocytosis). RESULTS: We did not observe significant differences between ND and CP for the total leukocyte and CD34(+) cell expansions nor for the myeloid progenitor production. In CP as well as in ND, the expanded cells were functionally competent. DISCUSSION: This suggests that the capacities of CD34(+) cells to proliferate and differentiate ex vivo are not impaired by prior chemotherapy and/or disease status. On the other hand, we did not observe any significant correlation between the number of mobilized CD34(+) cells before apheresis and the cell expansion. In conclusion, the ex vivo expansion of CP and ND cells is comparable and achievable even with a low CD34(+) cell number in mobilized peripheral blood.


Assuntos
Mobilização de Células-Tronco Hematopoéticas , Neoplasias/sangue , Neutrófilos/imunologia , Antígenos CD34/análise , Antineoplásicos/uso terapêutico , Remoção de Componentes Sanguíneos , Antígenos CD13/análise , Proliferação de Células , Ensaio de Unidades Formadoras de Colônias , Humanos , Imunofenotipagem , Neoplasias/tratamento farmacológico , Fagocitose , Explosão Respiratória
9.
Stem Cells Dev ; 14(4): 415-24, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16137231

RESUMO

Thrombocytopenia is a problematic and potentially fatal occurrence after transplantation of cord blood stem cells. This problem may be alleviated by infusion of megakaryocyte progenitor cells. Here, we compared the ability of hematopoietic progenitor cells obtained from cord blood and expanded in culture to that of mobilized peripheral blood cells. The CD34(+) cells were plated for 10 days in presence of thrombopoietin (TPO) alone and combined with stem cell factor (SCF), Flt3-ligand (FL), interleukin-3 (IL-3), IL-6, and IL-11. Cells were analyzed for the CD41 and CD42b expression and for their ploidy status. Ex vivo produced platelets were enumerated. We show that (1) TPO alone was able to induce differentiation of CD34(+) cells into CD41(+) cells, with limited total leucocyte expansion; (2) the addition of SCF to TPO decreased significantly CD41(+) cell percentage in CB, but not in MPB; and (3) in CB, the addition of FL, IL-6, and IL-11 to TPO increased the leukocyte expansion with differentiation and terminal maturation into MK lineage. In these conditions, high numbers of immature CD34(+)CD41(+) MK progenitor cells were produced. Our results thereby demonstrate a different sensitivity of CB and MPB cells to SCF, with limited CB MK differentiation. This different sensitivity to SCF (produced constitutively by BM stromal cells) could explain the longer delay of platelet recovery after CB transplant. Nevertheless, in CB, the combination of TPO with FL, IL-6, and IL-11 allows generation of a suitable number of immature MK progenitor cells expressing both CD34 and CD41 antigens, which are supposed to be responsible for the platelet recovery after transplantation.


Assuntos
Células Sanguíneas/citologia , Técnicas de Cultura de Células/métodos , Sangue Fetal/citologia , Megacariócitos/citologia , Células-Tronco/citologia , Antígenos CD34/biossíntese , Plaquetas/citologia , Diferenciação Celular , Linhagem da Célula , Transplante de Células , DNA/metabolismo , Citometria de Fluxo , Humanos , Interleucina-11/metabolismo , Interleucina-3/metabolismo , Interleucina-6/metabolismo , Leucócitos/metabolismo , Proteínas de Membrana/metabolismo , Fenótipo , Complexo Glicoproteico GPIb-IX de Plaquetas/biossíntese , Glicoproteína IIb da Membrana de Plaquetas/biossíntese , Ploidias , Fator de Células-Tronco/metabolismo , Trombopoetina/metabolismo , Fatores de Tempo
10.
Cytotherapy ; 5(2): 153-60, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12745577

RESUMO

BACKGROUND: Infusion of ex vivo generated myeloid post-progenitor cells associated with unmanipulated cells appears to be a promising approach to reduce neutropenia following cord blood (CB) transplant. We compared four commercially available serum-free media, two containing BSA and two containing human albumin, on the in vitro differentiation of CB CD34+ cells into post-myeloid progenitor cells. METHODS: CB CD34+ cells were cultured for 7 days in CTM-H00 (Mabio-International), StemSpanH2000 (StemCell Technologies), RM-B00 (Mabio-International) and Stem(alpha)A (Stem Alpha). The cells were stimulated by SCF, G-SCF, IL3 and Flt3-ligand (FL) added once at Day 0. Expansion was evaluated as the increase of leucocytes, CD34+ cells and CD13+ cells. Maturation of cells into the myeloid lineage was evaluated by expression of CD15, CD11b and CD16 Ags and by the presence of primary (myeloperoxydase, MPO) and secondary granules (lacoferrin, LF). The capacity of cells to phagocyte latex beads was evaluated to assess their functionality. RESULTS: We observed that: a) the mononuclear cell and CD34+ cell expansions were significantly different according to the medium tested (respectively 61.5 +/- 7.7 and 15.5 +/- 3.4 for RM-B00, 37.3 +/- 5.4 and 10.3 +/- 1.6 for CTM-H00, 23.2 +/- 6.5 and 5.8 +/- 0.9 for StemSpanH2000 and 16.6 +/- 2.4 and 3.9 +/- 0.7 for Stem(alpha)A; b) the expansion of myeloid precursors is higher with RM-B00, similar with CTM-H00 and StemSpanH2000, and lower with Stem(alpha)A. This difference is essentially due to total leucocyte expansion, rather than to a selective expansion of myeloid cells, except for Stem(alpha)A, for which the percentages of neutrophil precursor cells [promyelocytes (CD15+ CD11b+), myelocytes (CD11b+ CD16-) and mature cells (CD11b+ CD16+)] are significantly decreased. DISCUSSION: It appears that during ex vivo differentiation into myeloid lineages, the medium is critical and should be systematically screened before use in preclinical protocols. The use of human rather than bovine albumin, seems to have neither a negative, nor positive impact on the effectiveness of the medium.


Assuntos
Albuminas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Meios de Cultura Livres de Soro/farmacologia , Transplante de Células-Tronco Hematopoéticas/métodos , Células Progenitoras Mieloides/efeitos dos fármacos , Células Progenitoras Mieloides/transplante , Animais , Antígenos CD34/imunologia , Bovinos , Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Recém-Nascido
11.
Cytotherapy ; 5(1): 87-98, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12745585

RESUMO

BACKGROUND: Neutropenia following cord blood (CB) transplantation may be abrogated by infusion of granulopoietic progenitor cells. The purpose of this study was to determine whether myeloid progenitors can be obtained by ex vivo expansion of cryopreserved cord blood aliquots, and whether these progenitors present the morphologic, biologic and functional properties of myeloid progenitors at various stages of differentiation. METHODS: The cells, plated for 7 days in serum-free medium with SCF, IL-3, G-CSF, Flt3-ligand and thrombopoietin in various combinations were assessed for the expression of CD34, CD38 and CD13. Maturation of cells into the myeloid lineage was evaluated by the expression of CD15, CD11b and CD16 and by the presence of primary (myeloperoxidase) and secondary granules (lactoferrin). The capacity of cells to phagocyte latex beads was evaluated to assess their functionality. RESULTS: We have shown that a). CD34+ cells isolated from thawed samples were able to produce expansions similar to fresh samples. b). The best combination for the expansion of neutrophil precursor cells was S3FG; c). in these conditions, all stages of myeloid progenitors were represented, but few mature cells were observed. d). However, when the cells were plated on a BM stroma to try to reproduce conditions occurring during transplant, they acquired rapidly the characteristics of mature segmented cells. e). The ex vivo generated granulocytes were able to phagocyte latex beads. DISCUSSION: In conclusion, it seems reasonable to systematically aliquot CB samples before cryopreservation. Some aliquots can then be thawed, enriched in CD34+ cells and ex vivo differentiated into myeloid lineage, while the other aliquots are conserved to be infused without manipulation.


Assuntos
Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Criopreservação , Sangue Fetal/citologia , Células Progenitoras Mieloides/fisiologia , Proteínas Recombinantes de Fusão , Antígenos CD34/imunologia , Bioensaio , Células da Medula Óssea , Fator Estimulador de Colônias de Granulócitos , Fatores de Crescimento de Células Hematopoéticas , Humanos , Interleucina-3 , Células Progenitoras Mieloides/citologia , Células Progenitoras Mieloides/imunologia , Neutrófilos/fisiologia , Fagocitose/fisiologia , Proteínas Recombinantes
12.
Bull Mem Acad R Med Belg ; 157(1-2): 135-45; discussion 145-6, 2002.
Artigo em Francês | MEDLINE | ID: mdl-12371277

RESUMO

The haematopoietic stem cell (HSC) has been first described in the mouse and now identify in human as well. Exposed to a cocktail of growth factor, this HSC can self re-new and/or differentiate into the three lineages we have in the peripheral blood. These HSC are of major importance in the clinics since they can be used for some marrow (or stem cell) transplantation, and lead to the cure of a number of malignant and non malignant hemopathies. We have today three sources of HSC: the bone marrow, the mobilized peripheral blood stem cell and the cord blood. Bone marrow used to be the classical source of HSC after harvesting by aspirations in the iliac crest. However, this approach is now supplanted by the recovery of HSC in peripheral blood using a cell separation after four days of G-CSF administration. These are several advantages of this technique, but the most important one is the more rapid hematopoietic recovery after transplantation, reducing the risk of infection and transfusion. A recent source of HSC is the umbilical cord blood. At the moment of delivery, the cord blood is extremely enriched in HSC due to the migration of these cells from the liver to the bone marrow stroma, where they will persist after birth. We have learned that the marrow stroma display a major role in the regulation of hematopoiesis and the pathogenesis of several malignant hemopathies can be explained by disturbance in the function of stromal cell. We have particularly studied the patho-genesis of chronic lymphocytic leukaemia. We have also observed that a subpopulation of stromal cells, the mesenchymal cells are of major importance in the microenvironment. In addition, the plasticity of these cells is demonstrated in vitro and we have currently a research program investigating its differentiation in neural cells. All these observations bring new promises in the treatment of hemopathies but also in some other neurological degenerative diseases.


Assuntos
Neoplasias Hematológicas/terapia , Células-Tronco Hematopoéticas/citologia , Neoplasias/terapia , Transplante de Células-Tronco , Animais , Transplante de Medula Óssea , Sangue Fetal/citologia , Mobilização de Células-Tronco Hematopoéticas , Humanos , Recém-Nascido , Camundongos
13.
Bone Marrow Transplant ; 25(4): 377-83, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10723580

RESUMO

We characterized CD34+ cells purified from bone marrow (BM), mobilized peripheral blood (PB) and cord blood (CB) and we tried to establish correlations between the cell cycle kinetics of the CD34+CD38- and CD34+CD38+ subpopulations, their sensitivity to SCF and IL-3 and their expression of receptors for these two CSFs. At day 0, significantly fewer immature CD34+CD38- cells from CB and mobilized PB are in S + G2M phases of the cell cycle (respectively 2.0 +/- 0.4 and 0.9 +/- 0.3%) than their BM counterpart (5.6 +/- 1.2%). A 48-h incubation with SCF + IL-3 allows a significant increase in the percentage of cycling CD34+CD38- cells in CB (19.2 +/- 2.2%, P < 0.0002) and PB (14.1 +/- 5.5%, P < 0.05) while the proliferative potential of BM CD34+CD38- progenitors remains constant (8.6 +/- 1.0%, NS). CD123 (IL-3 receptor) expression is similar in the three sources of hematopoietic cells at day 0 and after 48-h culture. CD117 (SCF receptor) expression, although very heterogeneous according to the subpopulations and the sources of progenitors evaluated, seems not to correlate with the difference of progenitor cell sensitivity to SCF nor with their proliferative capacity. Considering the importance of the c-kit/SCF complex in the adhesion of stem cells to the microenvironment, several observations are relevant. The density of CD117 antigen expression (expressed in terms of mean equivalent soluble fluorescence, MESF) is significantly lower on fresh PB cells than on their BM (P < 0.017) and CB (P < 0.004) counterparts, particularly in the immature CD34+CD38- population (560 +/- 131, 2121 +/- 416 and 1192 +/- 129 MESF respectively); moreover, when PB and BM CD34+CD38- cells are stimulated for 48 h with SCF + IL-3, the CD117 expression decreases by 1.5- and 1.66-fold, respectively. This reduction could modify the functional capacities of ex vivo PB and BM manipulated immature progenitor cells.


Assuntos
Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas , Interleucina-3/farmacologia , Fator de Células-Tronco/farmacologia , Antígenos CD34 , Medula Óssea , Sangue Fetal , Células-Tronco Hematopoéticas/citologia , Humanos
14.
Leuk Lymphoma ; 35(5-6): 445-53, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10609782

RESUMO

B-cell chronic lymphocytic leukemia (B-CLL) is characterized by the accumulation of monoclonal long-lived B cells which are apparently resistant to normal apoptotic regulation. Since bone marrow stromal cells play an essential role in B lymphopoiesis, we have investigated whether stromal cells influence B-CLL cell survival. Our results indicate that intimate contact with stromal cells reduces B-CLL cell apoptosis and prevents the loss of bcl-2 protein expression. Binding of B-CLL cells to stromal cells requires simultaneous action of beta1 and beta2 integrins. The interaction between B-CLL cells and other cell types seems important for their survival and may represent an important mechanism underlying accumulation of malignant cells in B-CLL patients.


Assuntos
Apoptose/fisiologia , Linfócitos B/patologia , Comunicação Celular , Leucemia Linfocítica Crônica de Células B/patologia , Proteínas de Neoplasias/fisiologia , Células-Tronco Neoplásicas/citologia , Células Estromais/citologia , Antígenos CD18/fisiologia , Adesão Celular , Sobrevivência Celular , Regulação Leucêmica da Expressão Gênica , Genes bcl-2 , Humanos , Integrina beta1/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
15.
Blood ; 91(7): 2387-96, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9516138

RESUMO

The leukemic B lymphocytes from chronic lymphocytic leukemic (CLL) patients have a long survival in vivo, although ex vivo they rapidly die by apoptosis. To further investigate the mechanism of this, we have studied the influence of bone marrow stromal cells from normal subjects on apoptosis of B-CLL cells and normal umbilical cord blood (UCB) B lymphocytes. After 48 hours of incubation in medium alone, leukemic and normal B cells showed, respectively, 22 +/- 3% and 31 +/- 5% of apoptosis. Cocultures with stromal cells reduced the percentage of leukemic cells undergoing apoptosis (8 +/- 2%, P < . 0005) and prevented the loss of bcl-2 protein expression. In contrast, stromal cells slightly increased normal B-cell apoptosis (37 +/- 6%). Direct contact between leukemic cells and stromal cells was found to be essential for inhibition of leukemic cell apoptosis; indeed, separation of leukemic cells from stromal cells by microporous membrane increased spontaneous apoptosis, and comparable results were obtained with stromal cell conditioned medium. The difference in behavior observed between normal and leukemic B cells plated on stromal cells can be explained by the fact that only a few normal B cells adhere to stromal cells in comparison with B-CLL cells. B-CLL cell adhesion to stromal cells is mediated by beta1 and beta2 integrins acting simultaneously. Contact between B-CLL cells and bone marrow stromal cells seems to play a major role in the accumulation and survival of B-CLL cells in the bone marrow.


Assuntos
Apoptose , Linfócitos B/patologia , Comunicação Celular , Leucemia Linfocítica Crônica de Células B/patologia , Células Estromais/patologia , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/metabolismo , Células da Medula Óssea/patologia , Técnicas de Cocultura , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese
16.
J Hematother ; 6(2): 93-102, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9131438

RESUMO

CD34+ cord blood (CB) cells were expanded in stromal cell-free long-term culture (LTC), in the presence of various combinations of interleukin-3 (IL-3), stem cell factor (SCF), IL-6, granulocyte-macrophage colony-stimulating factor (GM-CSF), and anti-transforming growth factor-beta (anti-TGF-beta) antibody. The progenitor cell expansion was evaluated by monitoring the increase of CD34+ and CD34 + CD38- cells over a period of 21 days. The expansion of immature (B1-CFC, HPP-CFC) and of more committed progenitors (CFU-GM, CFU-GEMM, BFU-E) was also evaluated in specific samples. Our results show that (a) CD34+ cell expansion is highly variable depending on the cord blood samples studied, (b) significant correlations between B1-CFC and CD34 + CD38- and between total CFU and CD34+ cell expansion are observed, (c) SCF in combination with IL-3 appears to expand cell subsets that continue to express their CD34 + CD38- phenotype and that generate both immature and committed progenitors, and (d) the addition of IL-6, GM-CSF, or anti-TGF-beta does not significantly improve these expansions.


Assuntos
Antígenos CD34/análise , Antígenos de Diferenciação/análise , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , N-Glicosil Hidrolases/análise , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Antígenos CD/biossíntese , Antígenos CD34/biossíntese , Antígenos de Diferenciação/biossíntese , Técnicas de Cultura de Células/métodos , Divisão Celular , Separação Celular/instrumentação , Separação Celular/métodos , Sangue Fetal/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Células-Tronco Hematopoéticas/imunologia , Humanos , Imunofenotipagem , Interleucina-3/farmacologia , Interleucina-6/farmacologia , Glicoproteínas de Membrana , N-Glicosil Hidrolases/biossíntese , Fator de Crescimento Transformador beta/imunologia
17.
Stem Cells ; 13(3): 281-8, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7613494

RESUMO

Human umbilical cord blood (UCB) cells are currently considered as a potential source of stem cells for transplantation. However, it remains unclear whether a single collection of UCB contains enough progenitors to allow a successful engraftment in adult patients. We were interested in the comparison of the frequency of primitive progenitors in UCB and in human bone marrow (BM). UCB and BM CD34+ cells were purified and compared for their coexpression of CD38, CD33 and HLA-DR. UCB and BM mononuclear fractions were enriched in CD34+ cells using the CEPRATE LC system (CellPro, Bothell, WA). Double-labeling analysis with a flow cytometer showed that 67.9 +/- 7.2% of UCB CD34+ cells are CD38-, while in BM only 10.9 +/- 4.9% of CD34+ are CD38- (p < 0.001). Moreover, our study indicated that a significantly higher percentage of UCB CD34+ is CD33- (97.1 +/- 1.2%) compared to BM (61.8 +/- 8.6%) (p = 0.013). The coexpression of CD34 with HLA-DR was not significantly different in UCB and in BM (respectively, 86.3 +/- 2.7% and 92.7 +/- 5.1%). On the other hand, in vitro assays showed that the number of multipotent (colony-forming units granulocyte-erythroid-macrophage-megakaryocyte [CFU-GEMM]), myeloid (colony-forming units granulocyte-macrophage [CFU-GM]) and erythroid (burst-forming units-erythroid [BFU-E]) progenitors is lower in the CD34+ population from UCB than from BM. In conclusion, in UCB, we have found a significantly higher percentage of CD34+ cells which lacked the expression of CD38 and CD33 antigens suggesting that UCB contains higher proportions of immature progenitor cells (CD34+CD38- and CD34+CD33-) than BM. It seems thus likely that fewer UCB CD34+ cells than BM CD34+ cells would be required for sustained engraftment following transplantation.


Assuntos
Antígenos CD/análise , Células da Medula Óssea , Células Precursoras Eritroides/imunologia , Sangue Fetal/citologia , Antígenos HLA-DR/análise , Antígenos CD/sangue , Separação Celular , Células Precursoras Eritroides/citologia , Antígenos HLA-DR/sangue , Transplante de Células-Tronco Hematopoéticas , Humanos
18.
Stem Cells ; 12(6): 616-25, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7533580

RESUMO

UNLABELLED: We evaluated the growth of cord blood myeloid progenitors or colony forming units granulocyte-macrophage (CFU-GM) and their response to various recombinant growth factors or colony stimulating factors (CSFs): interleukin 3 (IL-3), IL-6, granulocyte-macrophage CSF (GM-CSF) and stem cell factor (SCF). Using classical stimulant (human placenta conditioned medium or HPCM), we observed a significantly higher day-14/day-7 CFU-GM ratio in CB than in bone marrow (BM). The association of IL-3, IL-6, GM-CSF and SCF induced significantly more CB day-14 CFU-GM than HPCM. This effect is significantly greater in CB than in bone marrow. Since fetal calf serum (FCS) is known to contain inhibitors, we have compared the ability of CSFs to induce CFU-GM formation in FCS-supplemented and FCS-free culture. In CB, using HPCM, we obtained significantly more CFU-GM in FCS-free medium than in FCS-supplemented medium. This difference was corrected by the addition of anti-transforming growth factor-beta (TGF-beta) neutralizing antibody. However, with the association of the four CSFs, no significant difference between FCS and FCS-free culture was observed. IN CONCLUSION: a) day-14/day-7 CFU-GM ratio was higher in CB than in BM indicating that CB CFU-GM are more primitive than BM CFU-GM; b) FCS can be successfully replaced by serum-free medium; c) FCS contains inhibitors of day-14 CFU-GM and among them TGF-beta; and d) the association IL-3, SCF, GM-CSF and IL-6 seems able to totally overcome the inhibitory effect of FCS.


Assuntos
Sangue Fetal/citologia , Substâncias de Crescimento/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Células da Medula Óssea , Ensaio de Unidades Formadoras de Colônias , Meios de Cultura , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Hematopoese/efeitos dos fármacos , Hematopoese/fisiologia , Fatores de Crescimento de Células Hematopoéticas/farmacologia , Células-Tronco Hematopoéticas/citologia , Humanos , Técnicas In Vitro , Recém-Nascido , Interleucina-3/farmacologia , Interleucina-6/farmacologia , Proteínas Recombinantes/farmacologia , Fator de Células-Tronco , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/fisiologia
19.
S Afr Med J ; 83(9): 660-2, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8310360

RESUMO

What were first called simply false-positive Wassermann reactions and then lupus anticoagulant are now known as antiphospholipid or anticardiolipin antibodies (ACA). These are known to cause a tendency to thrombosis and are frequently present in many neurological conditions and infections. The pathological significance of these antibodies in acute infections, if any, is unknown. We investigated the presence of these antibodies in Plasmodium falciparum malaria in an endemic area in Natal/KwaZulu, and attempted to correlate the presence of this antibody with cerebral manifestations. Immunoglobulin G-anticardiolipin antibodies measured by enzyme-linked immunosorbent assay occurred significantly more frequently in 62 patients with acute Plasmodium falciparum malaria (33.9%) than in 37 control subjects (2.7%) (P < 0.0001). There was no significant difference in the mean parasite loads in those patients who were positive for ACA (1.75%) and those who were negative (1.59%) (P = 0.83). No correlation was found between parasite load and ACA levels in the patient group, or between the number of cerebral manifestations in patients with and without the antibody. The frequency of splenomegaly was not significantly different in patients with and without ACA (P = 0.06). We conclude that there is a high prevalence of ACA in acute falciparum malaria. The pathological significance of this antibody and its relationship to complications, especially cerebral ones, warrant greater attention and may improve the understanding of cerebral malaria and its management.


Assuntos
Anticorpos Anticardiolipina/sangue , Malária Cerebral/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade
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