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1.
Nature ; 627(8003): 389-398, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38253266

RESUMEN

The human blood system is maintained through the differentiation and massive amplification of a limited number of long-lived haematopoietic stem cells (HSCs)1. Perturbations to this process underlie diverse diseases, but the clonal contributions to human haematopoiesis and how this changes with age remain incompletely understood. Although recent insights have emerged from barcoding studies in model systems2-5, simultaneous detection of cell states and phylogenies from natural barcodes in humans remains challenging. Here we introduce an improved, single-cell lineage-tracing system based on deep detection of naturally occurring mitochondrial DNA mutations with simultaneous readout of transcriptional states and chromatin accessibility. We use this system to define the clonal architecture of HSCs and map the physiological state and output of clones. We uncover functional heterogeneity in HSC clones, which is stable over months and manifests as both differences in total HSC output and biases towards the production of different mature cell types. We also find that the diversity of HSC clones decreases markedly with age, leading to an oligoclonal structure with multiple distinct clonal expansions. Our study thus provides a clonally resolved and cell-state-aware atlas of human haematopoiesis at single-cell resolution, showing an unappreciated functional diversity of human HSC clones and, more broadly, paving the way for refined studies of clonal dynamics across a range of tissues in human health and disease.


Asunto(s)
Linaje de la Célula , Hematopoyesis , Células Madre Hematopoyéticas , Humanos , Cromatina/genética , Cromatina/metabolismo , Células Clonales/clasificación , Células Clonales/citología , Células Clonales/metabolismo , ADN Mitocondrial/genética , Células Madre Hematopoyéticas/clasificación , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Mutación , Análisis de la Célula Individual , Transcripción Genética , Envejecimiento
2.
Braz. J. Pharm. Sci. (Online) ; 58: e19692, 2022. graf
Artículo en Inglés | LILACS | ID: biblio-1384014

RESUMEN

Abstract The development of stable cell lines producing recombinant proteins is very time-consuming and laborious. One of the practical approaches successfully performed is Fluorescence-Activated Cell Sorting (FACS). A mutated chimeric tissue plasminogen activator (mt-PA) was developed by removing the first three domains of t-PA, insertion of GHRP sequence and mutation toward resistance to plasminogen activator inhibitor-1 (PAI-1). In the current study, a new stable CHO-DG44 cell line producing mt-PA was developed by two sequential clonal selections: FACS and clonal-selection by limiting dilution. Furthermore, the expression was more evaluated using two different expression media. Finally, the high-producing clones were selected based on the dot blot and amidolytic activity test. The transfection efficiency of CHO-DG44 cells was 38% as measured by flow cytometry on green fluorescent protein (GFP). After performing FACS on stable cell pools, the expression yield was increased to fifty-fold. In terms of growth profile, CD-DG44 showed higher viability and cell density results than ProCHO5 medium. The expression of mt-PA was significantly higher in CD-DG44 than in ProCHO5, 765 and 280 IU/mL, respectively. Our data indicated that selection of an appropriate expression medium played a critical role in the development of potent producing stable cells by FACS.


Asunto(s)
Activador de Tejido Plasminógeno , Optimización de Procesos , Citometría de Flujo/métodos , Fluorescencia , Recuento de Células/instrumentación , Células Clonales/clasificación , Inhibidor 1 de Activador Plasminogénico/efectos adversos , Proteínas Fluorescentes Verdes
3.
São Paulo; s.n; s.n; 2021. 169 p. tab, ilus, graf.
Tesis en Portugués | LILACS | ID: biblio-1382043

RESUMEN

O aroma é um dos fatores mais importantes na determinação da qualidade e do caráter do vinho. Isso se deve à presença de compostos voláteis que estão associados às suas características organolépticas ou diferentes proporções entre estes compostos que podem ser influenciadas por fatores vitícolas (clima, solo, cultivar, manejo) e enológicos (maturação da uva, fermentação, tratamentos pósfermentativos). A região do sul de Minas Gerais vem se destacando na produção de espumantes de qualidade, e, nesse contexto, o presente trabalho teve como objetivo conhecer a influência do manejo da videira no desenvolvimento do aroma, da baga até o espumante, a fim de estabelecer associações com a qualidade do produto final. Os experimentos foram realizados com a cultivar Chardonnay em diferentes condições de manejo, em que foram avaliados clones, porta-enxertos, sistemas de condução e densidades de plantio. Foram analisados os compostos voláteis livres por HS-SPME/GC-MS das bagas, mostos, vinhos base e espumantes nas safras 2016, 2017 e 2018. O trabalho foi dividido em quatro partes para a apresentação dos resultados. A primeira consistiu em verificar a influência do material genético na composição volátil da cv. Chardonnay com os experimentos de clones e portaenxertos; a segunda parte avaliou a composição volátil do clone 809 até o espumante; a terceira, em analisar as vinificações dos diferentes sistemas de condução; e a quarta, em avaliar a evolução dos compostos voláteis da baga ao espumante e analisar os aromas que as densidades de plantio podem conferir ao espumante. As principais classes de compostos aromáticos identificados nas matrizes foram: C6-C9 aldeídos, álcoois superiores, aldeídos ramificados, benzenoides, monoterpenoides, norisoprenoides, sesquiterpenoides, cetonas e ácidos graxos. Os resultados mostraram que os clones e os porta-enxertos apresentaram perfis voláteis diferentes, indicando que a variabilidade entre os clones e que a enxertia têm influência no metabolismo da baga; o clone 809 apresenta maior abundância de compostos monoterpenoides, confirmando o seu caráter moscato, das uvas aos espumantes; os diferentes sistemas de condução e densidades de plantio alteram o metabolismo da14 baga, refletindo no perfil volátil dos espumantes nas safras estudadas. Dessa forma, os dados indicam que a composição volátil sofre influência do manejo da videira ao espumante


Aroma is one of the most important factors in determining the quality and character of wine. This is due to the presence of volatile compounds that are associated with their organoleptic characteristics or different proportions among these compounds that can be influenced by viticultural (climate, soil, cultivar, management) and oenological factors (grape maturation, fermentation, post fermentation treatments). The southern region of Minas Gerais has been standing out in the production of quality sparkling wines, and in this context, the purpose of the present work was to learn about the influence of grapevine management on the development of aroma, from berry to sparkling wine, in order to establish associations with the quality of the final product. The experiments were carried out with the Chardonnay cultivar under different management conditions, in which clones, rootstocks, trellising systems and planting densities were evaluated. The free volatile compounds by HS-SPME/GC-MS of the berries, musts, base and sparkling wines in the 2016, 2017 and 2018 harvests were analyzed. The work was divided into four parts in order to present the results. The first part consisted of verifying the influence of genetic material on the volatile composition of the cv. Chardonnay with the experiments on clones and rootstocks; the second part evaluated the volatile composition of clone 809 up to the sparkling wine; the third one part analyzed the vinification of the different trainig systems; and the fourth part evaluated the evolution of the volatile compounds from the berry to the sparkling wine and analyzed the aromas that the planting densities can confer to the sparkling wine. The main classes of aromatic compounds identified in the matrices were: C6-C9 aldehydes, higher alcohols, branched aldehydes, benzenoids, monoterpenoids, norisoprenoids, sesquiterpenoids, ketones and fatty acids. The results showed that the clones and the rootstocks have different volatile profiles, indicating that variability among clones and that grafting have great relevance to the berry secondary metabolism; the 809 clone presents a greater abundance of monoterpenoid compounds, confirming its muscat character, from grapes to sparkling wines; the different training systems and planting densities alter the berry´s metabolism, reflecting16 in the volatile profile of sparkling wines in the studied harvests. The data indicate that the volatile composition is influenced by the management of the berry to the sparkling wine


Asunto(s)
Vino/efectos adversos , Vitis/anatomía & histología , Espumantes , Producción de Cultivos , Células Clonales/clasificación , Gestión de la Calidad Total/métodos , Fermentación , Frutas
4.
Nature ; 571(7765): 355-360, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31270458

RESUMEN

Defining the transcriptomic identity of malignant cells is challenging in the absence of surface markers that distinguish cancer clones from one another, or from admixed non-neoplastic cells. To address this challenge, here we developed Genotyping of Transcriptomes (GoT), a method to integrate genotyping with high-throughput droplet-based single-cell RNA sequencing. We apply GoT to profile 38,290 CD34+ cells from patients with CALR-mutated myeloproliferative neoplasms to study how somatic mutations corrupt the complex process of human haematopoiesis. High-resolution mapping of malignant versus normal haematopoietic progenitors revealed an increasing fitness advantage with myeloid differentiation of cells with mutated CALR. We identified the unfolded protein response as a predominant outcome of CALR mutations, with a considerable dependency on cell identity, as well as upregulation of the NF-κB pathway specifically in uncommitted stem cells. We further extended the GoT toolkit to genotype multiple targets and loci that are distant from transcript ends. Together, these findings reveal that the transcriptional output of somatic mutations in myeloproliferative neoplasms is dependent on the native cell identity.


Asunto(s)
Genotipo , Mutación , Trastornos Mieloproliferativos/genética , Trastornos Mieloproliferativos/patología , Neoplasias/genética , Neoplasias/patología , Transcriptoma/genética , Animales , Antígenos CD34/metabolismo , Calreticulina/genética , Línea Celular , Proliferación Celular , Células Clonales/clasificación , Células Clonales/metabolismo , Células Clonales/patología , Endorribonucleasas/metabolismo , Hematopoyesis/genética , Células Madre Hematopoyéticas/clasificación , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/patología , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Ratones , Modelos Moleculares , Trastornos Mieloproliferativos/clasificación , FN-kappa B/metabolismo , Neoplasias/clasificación , Células Madre Neoplásicas/citología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Mielofibrosis Primaria/genética , Mielofibrosis Primaria/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Respuesta de Proteína Desplegada/genética
5.
PLoS One ; 9(2): e89834, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24587067

RESUMEN

When primary cultures of normal cells are cloned, three types of colony grow, called holoclones, meroclones and paraclones. These colonies are believed to be derived from stem cells, transit-amplifying cells and differentiated cells respectively. More recently, this approach has been extended to cancer cell lines. However, we observed that meroclones from the prostate cancer cell line DU145 produce holoclones, a paradoxical observation as meroclones are thought to be derived from transit-amplifying cells. The purpose of this study was to confirm this observation and determine if both holoclones and meroclones from cancer cell lines contain stem cells. We demonstrated that both holoclones and meroclones can be serially passaged indefinitely, are highly proliferative, can self-renew to form spheres, are serially tumorigenic and express stem cell markers. This study demonstrates that the major difference between holoclones and meroclones derived from a cancer cell line is the proportion of stem cells within each colony, not the presence or absence of stem cells. These findings may reflect the properties of cancer as opposed to normal cells, perhaps indicating that the hierarchy of stem cells is more extensive in cancer.


Asunto(s)
Diferenciación Celular/fisiología , Células Clonales/citología , Neoplasias de la Próstata/fisiopatología , Células Madre/citología , Análisis de Varianza , Biomarcadores/metabolismo , Línea Celular Tumoral , Células Clonales/clasificación , Ensayo de Unidades Formadoras de Colonias , Fluorescencia , Humanos , Inmunohistoquímica , Masculino
6.
Blood ; 122(18): 3129-37, 2013 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-24030380

RESUMEN

Human cord blood (CB) offers an attractive source of cells for clinical transplants because of its rich content of cells with sustained repopulating ability in spite of an apparent deficiency of cells with rapid reconstituting ability. Nevertheless, the clonal dynamics of nonlimiting CB transplants remain poorly understood. To begin to address this question, we exposed CD34+ CB cells to a library of barcoded lentiviruses and used massively parallel sequencing to quantify the clonal distributions of lymphoid and myeloid cells subsequently detected in sequential marrow aspirates obtained from 2 primary NOD/SCID-IL2Rγ(-/-) mice, each transplanted with ∼10(5) of these cells, and for another 6 months in 2 secondary recipients. Of the 196 clones identified, 68 were detected at 4 weeks posttransplant and were often lympho-myeloid. The rest were detected later, after variable periods up to 13 months posttransplant, but with generally increasing stability throughout time, and they included clones in which different lineages were detected. However, definitive evidence of individual cells capable of generating T-, B-, and myeloid cells, for over a year, and self-renewal of this potential was also obtained. These findings highlight the caveats and utility of this model to analyze human hematopoietic stem cell control in vivo.


Asunto(s)
Diferenciación Celular , Proliferación Celular , Trasplante de Células Madre de Sangre del Cordón Umbilical/métodos , Sangre Fetal/citología , Animales , Antígenos CD34/metabolismo , Secuencia de Bases , Linaje de la Célula , Células Clonales/clasificación , Células Clonales/citología , Células Clonales/metabolismo , Código de Barras del ADN Taxonómico , Sangre Fetal/metabolismo , Citometría de Flujo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células HeLa , Humanos , Inmunofenotipificación , Subunidad gamma Común de Receptores de Interleucina/deficiencia , Subunidad gamma Común de Receptores de Interleucina/genética , Cinética , Ratones , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Datos de Secuencia Molecular , Oligonucleótidos/genética , Factores de Tiempo , Trasplante Heterólogo
7.
Zhonghua Zhong Liu Za Zhi ; 35(3): 164-9, 2013 Mar.
Artículo en Chino | MEDLINE | ID: mdl-23879994

RESUMEN

OBJECTIVE: To dynamically investigate the morphology of human gastric cancer SGC-7901 cell clones, and then compare the tumorigenic ability of different clones in order to identify the tumor stem cell clones. METHODS: Clones derived from gastric cancer SGC-7901 cells were assessed by morphological observation, and the clone formation rate and proportion of each clone were calculated. The expression of CD44 and CDX2 in different clones was detected by immunofluorescence microscopy and Western blot. Furthermore, different clones were isolated and cultured, and their self-renewal property was assayed. Cells of different clones were subcutaneously inoculated into nude mice and the tumorigenic ability of each group was determined. RESULTS: Clones derived from gastric cancer SGC-7901 cells had three types, i.e. clones of tight, transitional and loose types. The total clone formation rate was (9.80 ± 1.07)%, and the proportion of tight, transitional and loose type clones was 10.2%, 56.0% and 33.8%, respectively. The results of immunofluorescence microscopic examination showed that the signal of CD44 was significantly stronger in the tight clones than in the transitional and loose clones, however, the signal of CDX2 was weakest in the tight colonies. The results of Western blot were consistent with that of immunofluorescence microscopic observation. SGC-7901 cells of tight clones possessed strong ability of self-renewal and in vivo tumorigenicity in the nude mice. CONCLUSION: SGC-7901 cell clones vary in morphology and differentiation, and the tight type clones may include rich gastric cancer stem cells.


Asunto(s)
Diferenciación Celular , Células Madre Neoplásicas/citología , Neoplasias Gástricas/patología , Animales , Factor de Transcripción CDX2 , Línea Celular Tumoral , Proliferación Celular , Células Clonales/clasificación , Femenino , Proteínas de Homeodominio/metabolismo , Humanos , Receptores de Hialuranos/metabolismo , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Células Madre Neoplásicas/metabolismo , Distribución Aleatoria , Neoplasias Gástricas/metabolismo
8.
Artículo en Inglés | MEDLINE | ID: mdl-21147007

RESUMEN

OBJECTIVE: Stem cells isolated from human dental follicles as a potential cell source for bone-tissue engineering were examined for correcting a critical bone defect. STUDY DESIGN: Impacted third molars were collected and single cell-derived cell populations were cultivated in growth medium. Single cell-derived cell lines were examined in terms of cell shape, gene expression patterns, differentiation capacity in vitro, and osteogenic potential in vivo. RESULTS: Three distinct cell populations were identified with different morphologies, patterns of gene expression, and differentiation capacity. All 3 cell populations promoted bone formation when transplanted into surgically created critical-size defects in immunodeficient rat calvaria, compared with control animals without cell transplantation, although one of these populations showed a weak capacity for osteogenetic differentiation in vitro. CONCLUSIONS: Human dental follicle can derive at least 3 unique cell populations in culture, all of which promote bone formation in vivo.


Asunto(s)
Células Madre Adultas/trasplante , Regeneración Ósea/fisiología , Saco Dental/citología , Osteogénesis/fisiología , Trasplante de Células Madre , Adipogénesis/fisiología , Células Madre Adultas/clasificación , Células Madre Adultas/citología , Animales , Diferenciación Celular , Línea Celular , Condrogénesis/fisiología , Células Clonales/clasificación , Células Clonales/citología , Células Clonales/trasplante , Humanos , Ratas , Ratas Endogámicas F344 , Cráneo/cirugía , Trasplante Heterólogo
9.
BMC Dev Biol ; 8: 89, 2008 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-18808670

RESUMEN

BACKGROUND: The central nervous tissue contains diverse subtypes of neurons with characteristic morphological and physiological features and different neurotransmitter phenotypes. The generation of neurons with defined neurotransmitter phenotypes seems to be governed by factors differently expressed along the anterior-posterior and dorsal-ventral body axes. The mechanisms of the cell-type determination, however, are poorly understood. Selected neuronal phenotypes had been generated from embryonic stem (ES) cells, but similar results were not obtained on more restricted neural stem cells, presumably due to the lack of homogeneous neural stem cell populations as a starting material. RESULTS: In the presented work, the establishment of different neurotransmitter phenotypes was investigated in the course of in vitro induced neural differentiation of a one-cell derived neuroectodermal cell line, in conjunction with the activation of various region-specific genes. For comparison, similar studies were carried out on the R1 embryonic stem (ES) and P19 multipotent embryonic carcinoma (EC) cells. In response to a short treatment with all-trans retinoic acid, all cell lines gave rise to neurons and astrocytes. Non-induced neural stem cells and self-renewing cells persisting in differentiated cultures, expressed "stemness genes" along with early embryonic anterior-dorsal positional genes, but did not express the investigated CNS region-specific genes. In differentiating stem-like cell populations, on the other hand, different region-specific genes, those expressed in non-overlapping regions along the body axes were activated. The potential for diverse regional specifications was induced in parallel with the initiation of neural tissue-type differentiation. In accordance with the wide regional specification potential, neurons with different neurotransmitter phenotypes developed. Mechanisms inherent to one-cell derived neural stem cell populations were sufficient to establish glutamatergic and GABAergic neuronal phenotypes but failed to manifest cathecolaminergic neurons. CONCLUSION: The data indicate that genes involved in positional determination are activated along with pro-neuronal genes in conditions excluding any outside influences. Interactions among progenies of one cell derived neural stem cells are sufficient for the activation of diverse region specific genes and initiate different routes of neuronal specification.


Asunto(s)
Diferenciación Celular/fisiología , Neuronas/citología , Células Madre/citología , Animales , Línea Celular , Células Cultivadas , Células Clonales/clasificación , Células Clonales/citología , Regulación del Desarrollo de la Expresión Génica/fisiología , Ratones , Neuronas/clasificación , Fenotipo , Células Madre/clasificación , Activación Transcripcional/fisiología , Tretinoina/fisiología
11.
Hum Reprod Update ; 12(3): 275-82, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16446319

RESUMEN

This review looks into the phylogeny of spermatogonial stem cells and describes their basic biological features. We are focusing on species-specific differences of spermatogonial stem cell physiology. We propose revised models for the clonal expansion of spermatogonia and for the potential existence of true stem cells and progenitors in primates but not in rodents. We create a new model for the species-specific arrangements of spermatogenic stages which may depend on the variable clonal expansion patterns. We also provide a brief overview of germ cell transplantation as a powerful tool for basic research and its potential use in a clinical setting.


Asunto(s)
Modelos Biológicos , Células Madre Pluripotentes/clasificación , Células Madre Pluripotentes/fisiología , Espermatogonias/clasificación , Espermatogonias/fisiología , Animales , Evolución Biológica , Células Clonales/clasificación , Células Clonales/citología , Células Clonales/fisiología , Humanos , Masculino , Células Madre Pluripotentes/citología , Ratas , Espermatogonias/citología , Trasplante de Células Madre
12.
Blood ; 107(6): 2311-6, 2006 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-16291588

RESUMEN

Hematopoietic stem cells (HSCs) display extensive heterogeneity in their behavior even when isolated as phenotypically homogeneous populations. It is not clear whether this heterogeneity reflects inherently diverse subsets of HSCs or a homogeneous population of HSCs diversified by their response to different external stimuli. To address this, we analyzed 97 individual HSCs in long-term transplantation assays. HSC clones were obtained from unseparated bone marrow (BM) through limiting dilution approaches. Following transplantation into individual hosts, donor-type cells in blood were measured bimonthly and the resulting repopulation kinetics were grouped according to overall shape. Only 16 types of repopulation kinetics were found among the HSC clones even though combinatorially 54 groups were possible. All HSC clones, regardless of their origin, could be assigned to this subset of groups, and the probability of finding new patterns is negligible. Thus, the full repertoire of repopulating HSCs was covered. These data indicate that the HSC compartment consists of a limited number of distinct HSC subsets, each with predictable behavior. Enrichment of HSCs (Lin- Rho- SP) changes the representation of HSC types by selecting for distinct subsets of HSCs. These data from the steady-state HSC repertoire could provide a basis for the diagnosis of perturbed patterns of HSCs potentially caused by disease or aging.


Asunto(s)
Células Madre Hematopoyéticas/citología , Animales , Linaje de la Célula , Células Clonales/clasificación , Células Clonales/citología , Trasplante de Células Madre Hematopoyéticas , Cinética , Ratones
13.
Int J Biol Markers ; 20(3): 177-83, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16240845

RESUMEN

PURPOSE AND METHODS: A large body of experimental evidence has confirmed that different tumors, including breast carcinomas, can stimulate specific T-cell-mediated immune responses. In this study we have analyzed patterns of T-cell clonality in tumor samples of 54 breast cancer patients classified as lymph node negative, N0 (n=16), or lymph node positive, N+ (n=38). The clonality of T-cells was analyzed by the PCR-PAGE method. RESULTS: Monoclonal/oligoclonal (M/O) T-cell populations were found in 15 breast cancer patients, nine N+ and six N0. In all analyzed groups (N+ + N0, N+, N0) the incidence of relapse was not significantly different between patients with M/O and patients with polyclonal T-cells. Comparison of disease-free interval (DFI) between patients divided according to the presence of TCRgamma monoclonality/oligoclonality showed a marginally significant difference only in the group of N+ patients within the first 24 months of follow-up. Patients with a M/O T-cell population had a shorter DFI than patients with a polyclonal T-cell population. This difference was not observed when the complete follow-up period was considered in the same group of patients. Furthermore, there was no significant difference in overall survival (OS) between patients with M/O and patients with polyclonal T-cells. CONCLUSION: Our results imply that tumor infiltrating T-cells are usually polyclonal. The pattern of T-cell clonality does not correlate with the incidence of relapse and the duration of DFI and OS in the analyzed groups of breast cancer patients, excluding N+ patients with M/O T-cells who had a shorter DFI in the first 24 months of follow-up. This observation suggests that polyclonal T-cell populations may provide a broader spectrum of T-cell-mediated antitumor response.


Asunto(s)
Neoplasias de la Mama/inmunología , Neoplasias de la Mama/patología , Linfocitos T/clasificación , Adulto , Células Clonales/clasificación , Supervivencia sin Enfermedad , Femenino , Humanos , Metástasis Linfática/patología , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/patología , Persona de Mediana Edad , Metástasis de la Neoplasia , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/patología , Linfocitos T/inmunología
14.
Arch Pathol Lab Med ; 129(3): 372-6, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15737033

RESUMEN

CONTEXT: Demonstration of a dominant T-cell clone in skin biopsy specimens by a molecular assay constitutes an additional diagnostic criterion to differentiate cutaneous T-cell lymphomas (CTCLs) from inflammatory dermatoses. OBJECTIVE: To determine which patients, depending on their clinical presentations, could most benefit from a cutaneous T-cell clonality analysis in addition to histopathologic analysis for the diagnosis of CTCL. DESIGN: Comparison of sensitivity and specificity of histopathologic analysis and a combination of this method and the detection of a T-cell receptor gamma chain gene rearrangement by polymerase chain reaction denaturing gradient gel electrophoresis performed on skin biopsy specimens obtained at initial presentation. PATIENTS: One hundred forty consecutive patients were classified into 4 groups, depending on their clinical presentation: (1) eczematous patches suggestive of early-stage mycosis fungoides (MF) (IA and IB of the TNM classification) (n = 42); (2) plaques, nodules, or tumors that arise on or are associated with plaques suggestive of late-stage MF (IIB and III of the TNM classification) (n = 16); (3) erythroderma (n = 50); and (4) nodules or tumors that arise in normal skin, suggestive of non-MF CTCL (n = 32). RESULTS: When compared with histopathologic examination, the addition of clonality analysis increased the sensitivity of CTCL diagnosis in all groups of patients except those with cutaneous lesions suggestive of late-stage MF, because the diagnosis was made based on histopathologic analysis alone in 100% of these cases. The main increase in sensitivity of CTCL diagnosis was observed in patients with erythroderma: 62% with histopathologic analysis alone to 87% with the combination of both methods (P = .04). Diagnostic specificity of molecular assays decreased from 100% to 76% (P = .01) in patients with patch lesions and from 100% to 70% (P = .04) in patients with nodules that occurred in normal skin due to the detection of a T-cell clone in 6 patients with follicular mucinosis without a histologic pattern of MF and in 5 of 20 cases of T-cell pseudolymphoma (25%), respectively. In contrast, a T-cell clone was not detected in the 34 patients with erythroderma of inflammatory origin. CONCLUSION: Polymerase chain reaction analysis of cutaneous T-cell clonality could be useful for the diagnosis of CTCL in patients who present with erythroderma.


Asunto(s)
Células Clonales/clasificación , Dermatitis Exfoliativa/complicaciones , Linfoma Cutáneo de Células T/complicaciones , Linfoma Cutáneo de Células T/diagnóstico , Piel/patología , Linfocitos T/clasificación , Humanos
15.
J Periodontal Res ; 39(2): 136-42, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15009522

RESUMEN

OBJECTIVES: Periodontal disease is an infectious disorder caused by a small subset of periodontal pathogens including Porphyromonas gingivalis. Accumulated evidences show that the expression of P. gingivalis heterogenic virulence properties is dependent on its clonal diversity. P. gingivalis expresses two distinct fimbria molecules, major and minor fimbriae, on its cell surfaces, both of which seem to be involved in the development of periodontitis. In this short review, variations of fimbriae in relation to microbial pathogenesis are discussed. MATERIALS AND METHODS: Our recent findings are summarized to elucidate the relationship between clonal variation of fimbriae and bacterial pathogenicity of various strains. RESULTS: Major fimbriae were classified into six types (I to V and Ib) based on the diversity of fimA genes encoding FimA (a subunit of major fimbriae). A majority of periodontitis patients were found to carry type II fimA organisms, followed by type IV, and type II fimA organisms were significantly occurred with more severe forms of periodontitis. Studies of clones with type II fimA have revealed significantly greater adhesive and invasive capabilities to epithelial cells than other fimA type clones. Minor fimbriae induced interleukin-1alpha (IL-1alpha), IL-1beta, IL-6, and tumor necrosis factor-alpha (TNF-alpha) cytokine expression in macrophages and were suggested to be a causative factor of alveolar bone resorption in animal models. The clonal diversity of minor fimbriae is unclear, however, distinct minor fimbria molecules were found in different strains. CONCLUSION: The fimbria variations may have an influence on the development of periodontal disease.


Asunto(s)
Fimbrias Bacterianas/clasificación , Periodontitis/microbiología , Porphyromonas gingivalis/patogenicidad , Animales , Células Clonales/clasificación , Fimbrias Bacterianas/genética , Humanos , Porphyromonas gingivalis/clasificación , Virulencia
16.
J Neurosci ; 23(6): 2314-22, 2003 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-12657690

RESUMEN

Analysis of cellular morphology is the most general approach to neuronal classification. With the increased use of genetically engineered mice, there is a growing need for methods that can selectively visualize the morphologies of specified subsets of neurons. This capability is needed both to define cell morphologic phenotypes and to mark cells in a noninvasive manner for lineage studies. To this end, we describe a bipartite genetic system based on a Cre-estrogen receptor (ER) fusion protein that irreversibly activates a plasma membrane-bound alkaline phosphatase reporter gene by site-specific recombination. Because the efficiency and timing of gene rearrangement is controlled pharmacologically, a sparse subset of labeled cells can be generated from the set of CreER-expressing cells at any time during development. Histochemical visualization of alkaline phosphatase activity reveals neuronal morphology with strong and uniform labeling of all processes.


Asunto(s)
Células Clonales/clasificación , Células Clonales/citología , Histocitoquímica/métodos , Neuronas/clasificación , Neuronas/citología , Fosfatasa Alcalina/análisis , Fosfatasa Alcalina/metabolismo , Animales , Encéfalo/citología , Encéfalo/crecimiento & desarrollo , Linaje de la Célula/fisiología , Células Clonales/metabolismo , Marcación de Gen , Genes Reporteros , Integrasas/genética , Ratones , Neuronas/metabolismo , Fenotipo , Receptores de Estrógenos/genética , Proteínas Recombinantes de Fusión/efectos de los fármacos , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Recombinación Genética , Reproducibilidad de los Resultados , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Tamoxifeno/farmacología , Transgenes , Proteínas Virales/genética
17.
Int J Mol Med ; 10(1): 113-7, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12060861

RESUMEN

A previous patho-epidemiological study indicated that thyroid lymphoma (TL) evolves among active lymphoid cells into chronic lymphocytic thyroiditis (CLTH), a thyroid-specific autoimmune disease. In this study, clonality of B-cells in the CLTH and TL lesions was analyzed using polymerase chain reaction (PCR)-based method on surgically resected samples from 10 cases of TL; 7 mucosa-associated lymphoid tissue (MALT) lymphoma and 3 diffuse large B-cell lymphoma (DLBCL). CLTH lesions coexisted in all the cases with MALT lymphoma, but not in the three DLBCL cases. In cases of MALT lymphoma, the lymphomatous and CLTH areas were separately microdissected from each section and analyzed for clonality. In the cases of DLBCL, the whole specimens were used for clonality analysis. CLTH lesions showed smear in 6 samples, two bands in one, and more than three (oligoclonal pattern) in 2. MALT lymphoma lesions showed single or two bands (monoclonal pattern) in 4, oligoclonal pattern in 4, and smear in one. DLBCL showed monoclonal pattern in two and oligoclonal pattern in one. One common band was present among two separate MALT lesions in one case, but no common bands were found in the remaining six cases. These findings suggested the clonal evolution of B-cell from polyclonal to monoclonal proliferation to take place in the continuum of lymphoproliferative lesions into autoimmune thyroiditis.


Asunto(s)
Linfocitos B , Células Clonales , Linfoma/patología , Reacción en Cadena de la Polimerasa , Neoplasias de la Tiroides/patología , Anciano , Linfocitos B/patología , Células Clonales/clasificación , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Linfoma/metabolismo , Masculino , Persona de Mediana Edad , Glándula Tiroides/inmunología , Glándula Tiroides/patología , Neoplasias de la Tiroides/inmunología , Neoplasias de la Tiroides/metabolismo , Tiroiditis Autoinmune/inmunología , Tiroiditis Autoinmune/patología
18.
Mem. Inst. Oswaldo Cruz ; 96(suppl): 89-101, Sept. 2001. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-295895

RESUMEN

T cell clones were derived from peripheral blood mononuclear cells of Schistosoma haematobium infected and uninfected individuals living in an endemic area. The clones were stimulated with S. haematobium worm and egg antigens and purified protein derivative. Attempts were made to classify the T cell clones according to production of the cytokines IL-4, IL-5 and IFN-gamma. All the T cell clones derived were observed to produce cytokines used as markers for the classification of Th1/Th2 subsets. However, the 'signature' cytokines marking each subset were produced at different levels. The classification depended on the dominating cytokine type, which was having either Th0/1 or Th0/2 subsets. The results indicated that no distinct cytokine profiles for polarisation of Th1/Th2 subsets were detected in these S. haematobium infected humans. The balance in the profiles of cytokines marking each subset were related to infection and re-infection status after treatment with praziquantel. In the present study, as judged by the changes in infection status with time, the T cell responses appeared to be less stable and more dynamic, suggesting that small quantitative changes in the balance of the cytokines response could result in either susceptibility or resistant to S. haematobium infection


Asunto(s)
Humanos , Animales , Niño , Citocinas/biosíntesis , Schistosoma haematobium/inmunología , Esquistosomiasis Urinaria/inmunología , Linfocitos T Colaboradores-Inductores/clasificación , Antihelmínticos/uso terapéutico , Antígenos Helmínticos , Línea Celular , Células Clonales/clasificación , Células Clonales/metabolismo , Citocinas/análisis , Citocinas/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática , Estudios de Seguimiento , Recuento de Huevos de Parásitos , Praziquantel/uso terapéutico , Esquistosomiasis Urinaria/tratamiento farmacológico , Subgrupos de Linfocitos T/clasificación , Subgrupos de Linfocitos T/metabolismo , Linfocitos T Colaboradores-Inductores/metabolismo , Células TH1/clasificación , Células TH1/metabolismo , Células Th2/clasificación , Células Th2/metabolismo , Volumetría
20.
Artículo en Inglés | MEDLINE | ID: mdl-10883064

RESUMEN

In vitro osteoclast differentiation is supported by stromal cells. In order to isolate a stromal cell line that can support osteoclast differentiation, 22 cell lines were cloned from mouse bone marrow. One of these clones, TMS-14, is a line of preadipocytes that supports osteoclast-like cell formation without any bone resorbing factors; and another, TMS-12, is a line of preosteoblasts that supports osteoclast-like cell formation with bone resorbing factors such as prostaglandin E(2)(PGE(2)). The difference of these two lines for osteoclast formation was not related with their abilities of PGE(2)production, but with the expression of osteoclast differentiation factor (ODF, also called OPGL, RANKL, and TRANCE), which detected with RT-PCR, in both cell lines. In TMS-14 cells, ODF mRNA was detected with or without PGE(2). In TMS-12 cells, ODF expression was detected in the PGE(2)-treated cells alone. When TMS-14 cells were induced to undergo adipogenic differentiation in response to treatment with thiazolidinedione, a ligand and activator of peroxisome proliferator-activated receptor gamma (PPARgamma), the ability of TMS-14 cells to support osteoclast-like cell formation was prevented in the presence or absence of 1,25(OH)(2)D(3). The gene expression of ODF in TMS-14 cells was also inhibited by treatment with thiazolidinedione. These results suggest that adipogenesis in bone marrow cells is related to the ability to support osteoclast differentiation. This is the first report of a cloned stromal cell line that can support osteoclastogenesis without the treatment with any osteotropic factors. Furthermore, this murine clonal preadipose cell line may be useful for studying senescence-dependent osteoporosis.


Asunto(s)
Adipocitos/citología , Células de la Médula Ósea/citología , Osteoclastos/citología , Células del Estroma/citología , Tiazolidinedionas , Animales , Proteínas Portadoras/genética , Proteínas Portadoras/farmacología , Técnicas de Cultivo de Célula , Diferenciación Celular , Línea Celular/clasificación , Línea Celular/citología , Línea Celular/efectos de los fármacos , Células Clonales/clasificación , Células Clonales/citología , Células Clonales/efectos de los fármacos , Técnicas de Cocultivo , Dinoprostona/metabolismo , Dinoprostona/farmacología , Regulación hacia Abajo , Glicerofosfatos/farmacología , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/farmacología , Ratones , Ratones Endogámicos , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Ligando RANK , Receptor Activador del Factor Nuclear kappa-B , Bazo/citología , Tiazoles/farmacología
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