189 resultados para Peripheral blood lymphocytes
Resumo:
BACKGROUND: The dose intensity of chemotherapy can be increased to the highest possible level by early administration of multiple and sequential high-dose cycles supported by transfusion with peripheral blood progenitor cells (PBPCs). A randomized trial was performed to test the impact of such dose intensification on the long-term survival of patients with small cell lung cancer (SCLC). METHODS: Patients who had limited or extensive SCLC with no more than two metastatic sites were randomly assigned to high-dose (High, n = 69) or standard-dose (Std, n = 71) chemotherapy with ifosfamide, carboplatin, and etoposide (ICE). High-ICE cycles were supported by transfusion with PBPCs that were collected after two cycles of treatment with epidoxorubicin at 150 mg/m(2), paclitaxel at 175 mg/m(2), and filgrastim. The primary outcome was 3-year survival. Comparisons between response rates and toxic effects within subgroups (limited or extensive disease, liver metastases or no liver metastases, Eastern Cooperative Oncology Group performance status of 0 or 1, normal or abnormal lactate dehydrogenase levels) were also performed. RESULTS: Median relative dose intensity in the High-ICE arm was 293% (range = 174%-392%) of that in the Std-ICE arm. The 3-year survival rates were 18% (95% confidence interval [CI] = 10% to 29%) and 19% (95% CI = 11% to 30%) in the High-ICE and Std-ICE arms, respectively. No differences were observed between the High-ICE and Std-ICE arms in overall response (n = 54 [78%, 95% CI = 67% to 87%] and n = 48 [68%, 95% CI = 55% to 78%], respectively) or complete response (n = 27 [39%, 95% CI = 28% to 52%] and n = 24 [34%, 95% CI = 23% to 46%], respectively). Subgroup analyses showed no benefit for any outcome from High-ICE treatment. Hematologic toxicity was substantial in the Std-ICE arm (grade > or = 3 neutropenia, n = 49 [70%]; anemia, n = 17 [25%]; thrombopenia, n = 17 [25%]), and three patients (4%) died from toxicity. High-ICE treatment was predictably associated with severe myelosuppression, and five patients (8%) died from toxicity. CONCLUSIONS: The long-term outcome of SCLC was not improved by raising the dose intensity of ICE chemotherapy by threefold.
Resumo:
Because of the various matrices available for forensic investigations, the development of versatile analytical approaches allowing the simultaneous determination of drugs is challenging. The aim of this work was to assess a liquid chromatography-tandem mass spectrometry (LC-MS/MS) platform allowing the rapid quantification of colchicine in body fluids and tissues collected in the context of a fatal overdose. For this purpose, filter paper was used as a sampling support and was associated with an automated 96-well plate extraction performed by the LC autosampler itself. The developed method features a 7-min total run time including automated filter paper extraction (2 min) and chromatographic separation (5 min). The sample preparation was reduced to a minimum regardless of the matrix analyzed. This platform was fully validated for dried blood spots (DBS) in the toxic concentration range of colchicine. The DBS calibration curve was applied successfully to quantification in all other matrices (body fluids and tissues) except for bile, where an excessive matrix effect was found. The distribution of colchicine for a fatal overdose case was reported as follows: peripheral blood, 29 ng/ml; urine, 94 ng/ml; vitreous humour and cerebrospinal fluid, < 5 ng/ml; pericardial fluid, 14 ng/ml; brain, < 5 pg/mg; heart, 121 pg/mg; kidney, 245 pg/mg; and liver, 143 pg/mg. Although filter paper is usually employed for DBS, we report here the extension of this alternative sampling support to the analysis of other body fluids and tissues. The developed platform represents a rapid and versatile approach for drug determination in multiple forensic media.
Resumo:
SummarySimultaneous detection of aneuploidies for chromosomes 4, 6,10 and 17 by automated four color l-FISH in high hyperdiploid acute lymphoblastic leukemia: diagnostic assessment, clonal heterogeneity and chromosomal instability in adultsAnna Talamo BlandinService de Génétique Médicale, Unité de Cytogénétique du Cancer, CHUVAcute lymphoblastic leukemia (ALL) is a malignant hemopathy characterized by the accumulation of the immature lymphoid cells in the bone marrow and, most often, in the peripheral blood. ALL is a heterogeneous disease with distinct biological and prognostic entities. At diagnosis, cytogenetic and molecular findings constitute important and independent prognostic factors. High hyperdiploidy with 51-67 chromosomes (HeH), one of the largest cytogenetic subsets of ALL, in childhood particularly, is generally associated with a relatively favorable outcome. Chromosome gain is nonrandom, extracopies of some chromosome occurring more frequently than those of others. Concurrent presence of trisomy for chromosomes 4, 10 and 17 confers an especially good prognosis. The first aim of our work was to develop an automated four color interphase fluorescence in situ hybridization (l-FISH) methodology and to assess its ability to detect concurrent aneuploidies 4, 6, 10 and 17 in 10 ALL patients. Various combinations of aneuploidies were identified. All clones detected by conventional cytogenetics were also observed by l-FISH. However, in all patients, l-FISH revealed numerous additional abnormal clones, leading to a high level of clonal heterogeneity. Our second aim has been to investigate the nature and origin of this clonal heterogeneity and to test for the presence of chromosome instability (CIN) in HeH ALL at initial presentation. Ten HeH ALL and 10 non-HeH ALL patients were analysed by four colour l-FISH and numerical CIN values were determined for all four chromosomes together and for each chromosome and patient group, an original approach in ALL. CIN values in HeH ALL proved to be much higher than#iose in non-HeH ALL, suggesting that numerical CIN may be at the origin of the high level of clonal heterogeneity revealed by l-FISH. Our third aim has been to study the evolution of these cytogenetic features during the course of the disease in 10 HeH ALL patients. Clonal heterogeneity was also observed again during disease progression, particularly at relapse. Clones detected at initial presentation generally reappeared in relapse, in most cases with newly generated ones. A significant correlation between the number of abnormal clones and CIN suggested that the higher the instability, the larger the number of abnormal clones. Whereas clonal heterogeneity and its evolution most probably result from underlying chromosome instability, operating processes remain conjectural.RésuméLa leucémie lymphoblastique aiguë (LLA) est une hémopathie maligne qui résulte de l'accumulationde cellules lymphoïdes immatures dans la moelle osseuse, et, le plus souvent, dans le sangpériphérique également. La LLA est une affection hétérogène au sein de laquelle se distinguentplusieurs entités biologiques et pronostiques. Les données cytogénétiques et moléculaires font partieintégrante du diagnostic et jouent un rôle essentiel dans l'évaluation du pronostic. L'hyperdiploïdieélevée à 51-67 chromosomes (HeH), relativement fréquente, en particulier chez l'enfant, s'associe àun pronostic favorable. Le gain de chromosomes ne relève pas du hasard, certains chromosomesétant plus fréquemment impliqués que d'autres. La présence simultanée des trisomies 4, 6, et 17s'associe à un pronostic particulièrement bon. Le premier but du travail a été de développer uneméthode d'analyse automatique par hybridation in situ fluorescente interphasique (I-FISH) à 4couleurs et de tester sa capacité à identifier la présence simultanée d'aneuploïdies 4, 6, 10 et 17 dans10 cas de LLA. Différentes combinaisons d'aneuploïdies ont été identifiées. Tous les clones détectéspar cytogénétique conventionnelle l'ont été par I-FISH. Or, chez tous les patients, l'I-FISH a révélé denombreux clones anormaux additionnels générant un degré élevé d'hétérogénéité clonale. Notredeuxième but a été d'investiguer la nature et l'origine de cette hétérogénéité et de tester la présenced'instabilité chromosomique (CIN) chez les patients avec une LLA HeH en presentation initiale. DixLLA HeH et 10 LLA non-HeH ont été analysées par I-FISH et les valeurs de CIN numérique ont étédéterminées pour les 4 chromosomes ensemble et pour chaque chromosome et groupe de patients,approche originale dans la LLA. Ces valeurs étant beaucoup plus élevées dans la LLA HeH que dansla LLA non-HeH, elles favorisent l'hypothèse selon laquelle la CIN serait à l'origine de l'hétérogénéitéclonale révélée par I-FISH. Le troisième but de notre travail a été d'étudier l'évolution de cescaractéristiques cytogénétiques au cours de la maladie dans 10 cas de LLA HeH. L'hétérogénéitéclonale a été retrouvée lors de la progression de la maladie, en particulier en rechute, où les clonesanormaux détectés en présentation initiale réapparaissent, généralement accompagnés de clonesnouveaux. La corrélation existant entre nombre de clones anormaux et valeurs de CIN suggère queplus l'instabilité est élevée, plus le nombre de clones anormaux est grand. Bien que l'hétérogénéitéclonale et son évolution résultent très probablement de l'instabilité chromosomique, les processus àl'oeuvre ne sont pas entièrement élucidés.
Resumo:
Cancer progression is dependent, in part, on interactions between tumor cells and the host microenvironment. During pregnancy, physiological changes occur that include inflammation and reduced immunity, both of which can promote tumor growth. Accordingly, tumors are observed to be more aggressive and to have greater proclivity toward metastasis during pregnancy. In this work, myeloid-derived suppressor cells (MDSC), a population of heterogeneous and pluripotent cells that can down-regulate immune responses during pathological conditions, were studied in the context of mouse and human gestation. The gene expression profile of mouse MDSC has been shown to differ in pregnant and virgin mice, and the profile in pregnant animals bears similarity to that of MDSC associated with the tumor microenvironment. Common induced genes include Fibronectin1 and Olfactomedin4, which are known to be involved in extracellular matrix remodeling and tissue permissiveness to tumor cells implantation. Our observations suggest that mouse MDSC may represent a shared regulatory mechanism of tissue permissiveness that occurs during the physiological state of gestation and tumor growth. Pregnancy-associated changes in immunosuppressive myeloid cell activity have also been studied in humans. We show that CD33+ myeloid cells isolated from PBMC (peripheral blood mononuclear cells) of pregnant women are more strongly immunosuppressive on T cells than CD33+ cells removed from non-pregnant subjects. During murine gestation, decreased natural killer (NK) cell activity is responsible, at least in part, for the increase in experimental metastasis. However, although peripheral blood NK cell numbers and cytotoxicity were slightly reduced in pregnant women, neither appeared to be regulated by CD33+ cells. Nevertheless, based on its observed suppression of T cell responses, the CD33+ PBMC subset appears to be an appropriate myeloid cell population to study in order to elucidate mechanisms of immune regulation that occur during human pregnancy. Our findings regarding the immunosuppressive function of CD33+cells and the role of NK cells during human pregnancy are consistent with the notion that changes in the function of the immune system participate in the constitution of a permissive soil for tumour progression.
Resumo:
Approximately 3% of the world population is chronically infected with the hepatitis C virus (HCV), with potential development of cirrhosis and hepatocellular carcinoma. Despite the availability of new antiviral agents, treatment remains suboptimal. Genome-wide association studies (GWAS) identified rs12979860, a polymorphism nearby IL28B, as an important predictor of HCV clearance. We report the identification of a novel TT/-G polymorphism in the CpG region upstream of IL28B, which is a better predictor of HCV clearance than rs12979860. By using peripheral blood mononuclear cells (PBMCs) from individuals carrying different allelic combinations of the TT/-G and rs12979860 polymorphisms, we show that induction of IL28B and IFN-γ-inducible protein 10 (IP-10) mRNA relies on TT/-G, but not rs12979860, making TT/-G the only functional variant identified so far. This novel step in understanding the genetic regulation of IL28B may have important implications for clinical practice, as the use of TT/G genotyping instead of rs12979860 would improve patient management.
Resumo:
Cite this as: J. Wassenberg, S. Nutten, R. Audran, N. Barbier, V. Aubert, J. Moulin, A. Mercenier and F. Spertini, Clinical & Experimental Allergy, 2011 (41) 565-573. SUMMARY: Background Probiotics have been associated with prevention and improvement of symptoms in atopic diseases such as atopic dermatitis. However, few studies exist that document their efficacy for upper airways allergies such as allergic rhinitis. Objective To investigate the effect of short-term oral administration of Lactobacillus paracasei ST11 on a nasal provocation test (NPT) with grass pollen. Methods Thirty-one adult volunteers with allergic rhinitis were enrolled in a randomized, double-blind, placebo-controlled study, based on two 4-week cross-over periods of product consumption (ST11-fermented milk vs. placebo), separated by a wash-out period of 6-8 weeks. Objective and subjective clinical parameters of NPT as well as systemic and nasal immunological parameters were compared between the two treatment periods (registration number: NCT 011 50 253). Results Subjects that received ST11-fermented milk had lower nasal congestion than subjects under placebo (visual analogical scale; P<0.05). Nasal pruritus followed the same trend. However, no significant change in combined nasal reaction threshold was observed between the two periods. IL-5 secretion by peripheral blood mononuclear cells and serum allergen-specific IgG4 were significantly lower in ST11-fermented milk group compared to placebo group. IL-8 and IL-10 secretion followed the same trend. Conclusion and Clinical Relevance Short-term treatment with ST11-fermented milk before NPT significantly improved a clinical marker of NPT (subjective nasal congestion) and down-regulated systemic immune markers (IL-5 from peripheral blood mononuclear cells and serum IgG4). These data strongly suggest that probiotics may down modulate key parameters of allergic rhinitis and warrant future evaluation in seasonal trials.
Resumo:
Newborns are particularly susceptible to bacterial infections due to qualitative and quantitative deficiencies of the neonatal innate immune system. However, the mechanisms underlying these deficiencies are poorly understood. Given that fetuses are exposed to high concentrations of estradiol and progesterone during gestation and at time of delivery, we analyzed the effects of these hormones on the response of neonatal innate immune cells to endotoxin, bacterial lipopeptide, and Escherichia coli and group B Streptococcus, the two most common causes of early-onset neonatal sepsis. Here we show that at concentrations present in umbilical cord blood, estradiol and progesterone are as powerful as hydrocortisone for inhibition of cytokine production by cord blood mononuclear cells (CBMCs) and newborn monocytes. Interestingly, CBMCs and newborn monocytes are more sensitive to the effects of estradiol and progesterone than adult peripheral blood mononuclear cells and monocytes. This increased sensitivity is associated with higher expression levels of estrogen and membrane progesterone receptors but is independent of a downregulation of Toll-like receptor 2 (TLR2), TLR4, and myeloid differentiation primary response gene 88 in newborn cells. Estradiol and progesterone mediate their anti-inflammatory activity through inhibition of the NF-κB pathway but not the mitogen-activated protein kinase pathway in CBMCs. Altogether, these results suggest that elevated umbilical cord blood concentrations of estradiol and progesterone acting on mononuclear cells expressing high levels of steroid receptors contribute to impair innate immune responses in newborns. Therefore, intrauterine exposure to estradiol and progesterone may participate in increasing susceptibility to infection during the neonatal period.
Resumo:
Anti-CTLA-4 treatment improves the survival of patients with advanced-stage melanoma. However, although the anti-CTLA-4 antibody ipilimumab is now an approved treatment for patients with metastatic disease, it remains unknown by which mechanism it boosts tumor-specific T cell activity. In particular, it is unclear whether treatment amplifies previously induced T cell responses or whether it induces new tumor-specific T cell reactivities. Using a combination ultraviolet (UV)-induced peptide exchange and peptide-major histocompatibility complex (pMHC) combinatorial coding, we monitored immune reactivity against a panel of 145 melanoma-associated epitopes in a cohort of patients receiving anti-CTLA-4 treatment. Comparison of pre- and posttreatment T cell reactivities in peripheral blood mononuclear cell samples of 40 melanoma patients demonstrated that anti-CTLA-4 treatment induces a significant increase in the number of detectable melanoma-specific CD8 T cell responses (P = 0.0009). In striking contrast, the magnitude of both virus-specific and melanoma-specific T cell responses that were already detected before start of therapy remained unaltered by treatment (P = 0.74). The observation that anti-CTLA-4 treatment induces a significant number of newly detected T cell responses-but only infrequently boosts preexisting immune responses-provides strong evidence for anti-CTLA-4 therapy-enhanced T cell priming as a component of the clinical mode of action.
Resumo:
Cocaine is a well known trigger of acute coronary syndromes. Over the last 10 years levamisole, a veterinary anthelminthic drug has been increasingly used as an adulterant of cocaine. Levamisole was used to treat pediatric nephritic syndrome and rheumatoid arthritis before being withdrawn from the market due to its significant toxicity, i.e. hematological complications and vasculitis. The major complications of levamisole-adultered cocaine reported up to now are hematological and dermatological. The case reported here is of a 25 year old man with a history of cocaine abuse who died at home after complaining of retrosternal pain. Postmortem CT-angiography, autopsy, and chemical and toxicological analyses were performed. An eroded coronary artery plaque was found at the proximal segment of the left anterior descending coronary artery. Two myocardial infarct scars were present in the left ventricle. Microscopic examination of the coronary artery revealed infiltration of eosinophils into the adventitia and intima. Toxicological examination confirmed the presence of cocaine and its metabolites in the peripheral blood, and of levamisole in the urine and pericardial fluid. Eosinophilic inflammatory coronary artery pathologies have been clinically linked to coronary dissection, hypersensitivity coronary syndrome and vasospastic allergic angina. The coronary pathology in the presented case could be a complication of levamisole-adultered cocaine use, in which an allergic or immune-mediated mechanism might play a role. The rise in cocaine addiction worldwide and the increase of levamisole adulterated cocaine highlights the importance of updating our knowledge of the effects of adultered cocaine abuse.
Resumo:
RESUME Introduction: Les cellules T mémoires humaines sont classées en trois sous-populations sur la base de l'expression d'un marqueur de surface cellulaire, CD45RA, et du récepteur aux chimiokines, CCR7. Ces sous-populations, nommées cellules mémoires centrales (TcM), mémoires effectrices (TEM) et mémoires effectrices terminales (ITEM), ont des rôles fonctionnels distincts, ainsi que des capacités de prolifération et de régénération différentes. Cependant, la génération de ces différences reste encore mal comprise et on ignore les mécanismes moléculaires impliqués. Matériaux et Méthodes: Des cellules mononucléaires humaines du sang périphérique ont été séparées par cytométrie de flux selon leur expression de CD4, CD8, CD45RA et CCR7 en sous-populations de cellules CD4+ ou CD8+ naïves, TcM, TEM ou ITEM. Dans chacune de ces sous-populations, 14 gènes impliqués dans l'apoptose, la survie ou la capacité proliférative des cellules T ont été quantifiés par RT-PCR en temps réel, relativement à l'expression d'un gène de référence endogène. L'ARN provenant de 450 cellules T a été utilisé par gène et par sous-population. Les gènes analysés (cibles) comprenaient des gènes de survie (BAFF, APRIL, BAFF-R, BCMA, TACI, IL-15Rα, IL-7Rα), des gènes anti-apoptotiques (Bcl-2, BclxL, FLIP), des gènes pro-apoptotiques (Bad, Bax, Fast) et le gène anti-prolifératif, Tob. A l'aide de la méthode comparative delta-delta-CT, le taux d'expression des gènes cibles de chaque sous-population des cellules T mémoires CD4+ et CD8+, à été comparée à leur taux d'expression dans les cellules T naïves CD4+ et CD8+. Résultats: Dans les cellules CD8+, les gènes pro-apoptotiques Bax et Fast étaient surexprimés dans toutes les sous-populations mémoires, tandis que l'expression des facteurs anti-apoptotiques et de survie comme Bcl-2, APRIL et BAFF-R, étaient diminués. Ces deux tendances étaient particulièrement accentuées dans les sous-groupes des cellules mémoires TEM et TTEM. A noter que malgré le fait que leur expression était également diminuée dans les autres cellules mémoires, le facteur de survie IL-7Ra, était sélectivement surexprimé dans la sous-population de cellules TcM et l'expression d'IL-15Ra était sélectivement augmentée dans les TEM. Dans les cellules CD4+, le taux d'expression des gènes analysés était plus variable entre les sujets étudiés que dans les cellules CD8+, ne permettant pas de définir un profil d'expression spécifique. L'expression du gène de survie BAFF par contre, a été significativement augmentée dans toutes les sous-populations mémoire CD4+. Il en va de même pour l'expression d' APRIL et de BAFF-R, bien que dans moindre degré. A remarquer que l'expression du facteur anti-apoptotique Fast a été observée uniquement dans la souspopulation des TTEM. Discussion et Conclusions: Cette étude montre une nette différence entre les cellules CD8+ et CD4+, en ce qui concerne les profils d'expression des gènes impliqués dans la survie et l'apoptose des cellules T mémoires. Ceci pourrait impliquer une régulation cellulaire homéostatique distincte dans ces deux compartiments de cellules T mémoires. Dans les cellules CD8+ l'expression d'un nombre de gènes impliqués dans la survie et la protection de l'apoptose semblerait être diminuée dans les populations TEM et TTEM en comparaison à celle des sous-populations naïves et TEM, tandis que l'expression des gènes pro-apoptotiques semblerait être augmentée. Comme ceci paraît être plus accentué dans les TTEM, cela pourrait indiquer une plus grande disposition à l'apopotose dans les populations CCR7- (effectrices) et une perte de survie parallèlement à l'acquisition de capacités effectrices. Ceci parlerait en faveur d'un modèle de différentiation linéaire dans les cellules CD8+. De plus, l'augmentation sélective de l'expression d'IL-7Ra observée dans le sous-groupe de cellules mémoires TEM, et d'IL-15Ra dans celui des TEM, pourrait indiquer un moyen de sélection pour des réponses immunitaires mémoires à long terme par une réponse distincte à ces cytokines. Dans les cellules CD4+ par contre, aucun profil d'expression n'a pu être déterminé; les résultats suggèrent même une résistance relative à l'apoptose de la part des cellules mémoires. Ceci pourrait favoriser l'existence d'un modèle de différentiation plus flexible avec des possibilités d'interaction multiples. Ainsi, la surexpression sélective de BAFF, APRIL et BAFF-R dans les sous-populations individuelles des cellules mémoires pourrait être un indice de l'interaction de ces sous-groupes avec des cellules B. ABSTRACT Introduction: Based on their surface expression of the CD45 isoform and of the CCR7 chemokine receptor, memory T cells have been divided into the following three subsets: central memory (TAM), effector memory (TEM) and terminal effector memory (ITEM). Distinct functional roles and different proliferative and regenerative capacities have been attributed to each one of these subpopulations. The molecular mechanisms underlying these differences; however, remain poorly understood. Materials and Methods: According to their expression of CD4, CD8, CD45RA and CCR7, human peripheral blood mononuclear cells were sorted by flow-cytometry into CD4+ or CD8+ naïve, TAM, TEM and ITEM subsets. Using real-time PCR, the expression of 14 genes known to be involved in apoptotis, survival or proliferation of T cells was quantified separately in each individual subset, relative to an endogenous reference gene. The RNA equivalent of 450 T cells was used for each gene and subset. The target gene panel included the survival genes BAFF, APRIL, BAFF-R, BCMA, TACI, IL-15Rα and IL-7Rα, the anti-apoptotic genes Bcl2, Bcl-xL and FLIP, the pro-apoptotic genes Bad, Bax and Fast, as well as the antiproliferative gene Tob. Using the comparative CT-method, the expression of the target genes in the three memory T cell subsets of both CD4+ and CD8+ T cell populations was compared to their expression in the naïve T cells. Results: In CD8+ cells, the pro-apoptotic factors Bax and Fast were found to be upregulated in all memory T cell subsets, whereas the survival and anti-apoptotic factors Bcl-2, APRIL and BAFF-R were downregulated. These tendencies were most accentuated in TEM and TTEM subsets. Even though the survival factor IL-7Rα was also downregulated in these subsets, interestingly, it was selectively upregulated in the CD8+ TAM subset. Similarly, IL-15Rαexpression was shown to be selectively upregulated in the CD8+ TEM subset. In CD4+ cells, the expression levels of the analyzed genes showed a greater inter-individual variability than in CD8+ cells, thus suggesting the absence of any particular expression pattern for CD4+ memory T cells. However, the survival factor BAFF was found to be significantly upregulated in all CD4+ memory T cell subsets, as was also the expression of APRIL and BAFF-R, although to a lesser extent. Furthermore, it was noted that the pro-apoptotic gene Fast was only expressed in the TTEM CD4+ subset. Discussion and Conclusions: Genes involved in apoptosis and survival in human memory T cells have been shown to be expressed differently in CD8+ cells as compared to CD4+ cells, suggesting a distinct regulation of cell homeostasis in these two memory T cell compartments. The present study suggests that, in CD8+ T cells, the expression of various survival and antiapoptotic genes is downregulated in TEM and TTEM subsets, while the expression of proapoptotic genes is upregulated in comparison to the naïve and the TAM populations. These characteristics, potentially translating to a greater susceptibility to apoptosis in the CCR7- (effector) memory populations, are accentuated in the TTEM population, suggesting a loss of survival in parallel to the acquisition of effector capacities. This speaks in favour of a linear differentiation model in CD8+ T memory cells. Moreover, the observed selectively increased expression of IL-7Rα in CD8+ TAM cells - as that of IL-15Rα in CD8+ TEM cells -suggest that differential responsiveness to cytokines could confer a selection bias for distinct long-term memory cell responses. Relative to the results for CD8+ T cells, those for CD4+ T cells seem to indicate a certain resistance of the memory subsets to apoptosis, suggesting the possibility of a more flexible differentiation model with multiple checkpoints and potential interaction of CD4+ memory cells with other cells. Thus, the selective upregulation of BAFF, APRIL and BAFF-R in individual memory subsets could imply an interaction of these subsets with B cells.
Resumo:
Macrophages play a critical role in intestinal wound repair. However, the mechanisms of macrophage-assisted wound repair remain poorly understood. We aimed to characterize more clearly the repair activities of murine and human macrophages. Murine macrophages were differentiated from bone marrow cells and human macrophages from monocytes isolated from peripheral blood mononuclear cells of healthy donors (HD) or Crohn's disease (CD) patients or isolated from the intestinal mucosa of HD. In-vitro models were used to study the repair activities of macrophages. We found that murine and human macrophages were both able to promote epithelial repair in vitro. This function was mainly cell contact-independent and relied upon the production of soluble factors such as the hepatocyte growth factor (HGF). Indeed, HGF-silenced macrophages were less capable of promoting epithelial repair than control macrophages. Remarkably, macrophages from CD patients produced less HGF than their HD counterparts (HGF level: 84âeuro0/00±âeuro0/0027âeuro0/00pg/mg of protein and 45âeuro0/00±âeuro0/0034âeuro0/00pg/mg of protein, respectively, for HD and CD macrophages, Pâeuro0/00<âeuro0/000·009) and were deficient in promoting epithelial repair (repairing activity: 90·1âeuro0/00±âeuro0/004·6 and 75·8âeuro0/00±âeuro0/008·3, respectively, for HD and CD macrophages, Pâeuro0/00<âeuro0/000·0005). In conclusion, we provide evidence that macrophages act on wounded epithelial cells to promote epithelial repair through the secretion of HGF. The deficiency of CD macrophages to secrete HGF and to promote epithelial repair might contribute to the impaired intestinal mucosal healing in CD patients.
Resumo:
Introduction: Mantle cell lymphoma (MCL) accounts for 6% of all B-cell lymphomas and is in most cases an incurable disease. It is characterized by the translocation t(11;14) leading to Cyclin D1 over-expression. Cyclin D1 is downstream of the mammalian target of rapamycin (mTOR) threonine kinase and can be effectively blocked by mTOR inhibitors. We set out to define the single agent activity of the orally available mTOR inhibitor everolimus in a prospective, multicentre trial in patients with relapsed or refractory MCL (NCT00516412).Methods: Eligible patients with confirmed relapsed or refractory MCL received everolimus 10 mg for 28 days (one cycle) for a total of 6 cycles or until disease progression. The primary endpoint was the best objective response (OR) with adverse reactions, time to progression (TTP), time to treatment failure, response duration and molecular response as secondary endpoints.Results: A total of 36 patients with 35 evaluable patients at a median age of 69 years (range 40 to 85 years) from 19 centers were enrolled between August 2007 and January 2010. Treatment was generally well tolerated with anemia (11%), thrombocytopenia (11%), neutropenia (8%), diarrhea (3%) and fatigue (3%) being the most frequent complications of CTC grade 3 or higher. The OR rate was 20% (95% CI: 8-37%) with 2 complete remissions (CR) and 5 partial response (PR), stable disease (SD) 48% and progression disease (PD) 28%. At a median follow-up of 6 months, TTP was 5.45 months (95% CI: 2.8-8.2 months) for the entire population and 10.6 months for the 18 patients receiving 6 or more cycles of treatment. Three patients achieved a lasting complete molecular response when assessed in the peripheral blood.Conclusion: This study demonstrates that single agent everolimus is well tolerated and has anti-lymphoma activity including lasting molecular responses. Further studies of everolimus either in combination with chemotherapy or as single agent for maintenance treatment are warranted in MCL.
Resumo:
OBJECTIVE: Macrophages play a critical role in intestinal wound repair. However, the molecular pathways that regulate macrophage wound repair activities remain poorly understood. The aim of this study was to evaluate the role of GM-CSF receptor signaling in the wound repair activities of macrophages. METHODS: Murine macrophages were differentiated from bone marrow cells and human macrophages from monocytes isolated from peripheral blood mononuclear cells of Crohn's disease (CD) patients. In vitro models were used to study the repair activities of macrophages. RESULTS: We provide evidence that GM-CSF receptor signaling is required for murine macrophages to promote epithelial repair. In addition, we demonstrate that the deficient repair properties of macrophages from CD patients with active disease can be recovered via GM-CSF therapy. CONCLUSION: Our data support a critical role of the GM-CSF signaling pathway in the pro-repair activities of mouse and human macrophages. © 2014 S. Karger AG, Basel.
Resumo:
Introduction: Prior repeated-sprints (6) has become an interesting method to resolve the debate surrounding the principal factors that limits the oxygen uptake (V'O2) kinetics at the onset of exercise [i.e., muscle O2 delivery (5) or metabolic inertia (3)]. The aim of this study was to compare the effects of two repeated-sprints sets of 6x6s separated by different recovery duration between the sprints on V'O2 and muscular de-oxygenation [HHb] kinetics during a subsequent heavy-intensity exercise. Methods: 10 male subjects performed a 6-min constant-load cycling test (T50) at intensity corresponding to half of the difference between V'O2max and the ventilatory threshold. Then, they performed two repeated-sprints sets of 6x6s all-out separated by different recovery duration between the sprints (S1:30s and S2:3min) followed, after 7-min-recovery, by the T50 (S1T50 and S2T50, respectively). V'O2, [HHb] of the vastus lateralis (VL) and surface electromyography activity [i.e., root-mean-square (RMS) and the median frequency of the power density spectrum (MDF)] from VL and vastus medialis (VM) were recorded throughout T50. Models using a bi-exponential function for the overall T50 and a mono-exponential for the first 90s of T50 were used to define V'O2 and [HHb] kinetics respectively. Results: V'O2 mean value was higher in S1 (2.9±0.3l.min-1) than in S2 (1.2±0.3l.min-1); (p<0.001). The peripheral blood flow was increased after sprints as attested by a higher basal heart rate (HRbaseline) (S1T50: +22%; S2T50: +17%; p≤0.008). Time delay [HHb] was shorter for S1T50 and S2T50 than for T50 (-22% for both; p≤0.007) whereas the mean response time of V'O2 was accelerated only after S1 (S1T50: 32.3±2.5s; S2T50: 34.4±2.6s; T50: 35.7±5.4s; p=0.031). There were no significant differences in RMS between the three conditions (p>0.05). MDF of VM was higher during the first 3-min in S1T50 than in T50 (+6%; p≤0.05). Conclusion: The study show that V'O2 kinetics was speeded by prior repeated-sprints with a short (30s) but not a long (3min) inter-sprints-recovery even though the [HHb] kinetics was accelerated and the peripheral blood flow was enhanced after both sprints. S1, inducing a greater PCr depletion (1) and change in the pattern of the fibres recruitment (increase in MDF) compared with S2, may decrease metabolic inertia (2), stimulate the oxidative phosphorylation activation (4) and accelerate V'O2 kinetics at the beginning of the subsequent high-intensity exercise.
Resumo:
AbstractBackground: Mucosal healing is becoming a major goal in the treatment of Crohn's disease. It has been previously reported that myeloid cells induce mucosal healing in a mouse model of acute colitis. The aim in this study is to investigate the pro-repair function of myeloid cells in healthy donors (HD) and Crohn's disease patients (CD).Methods: Peripheral blood mononuclear cells (PBMC) from HD and CD patients were isolated from blood samples and tested either directly or after differentiation ex-vivo into macrophages (Μφ). Intestinal macrophages (IMACs) were isolated from the bowel mucosa of patients undergoing intestinal surgical resections. Through an in vitro wound healing assay the repairing ability of these various human myeloid cells and the mechanisms responsible of wound healing were evaluated.Results: PBMC and myeloid CD14+ cells from HD and CD were not able to repair at any tested cell concentration. Μφ from HD and ulcerative colitis (UC) patients were able to induce wound healing and this capacity was partially mediated by Hepatocyte Growth Factor (HGF). Remarkably, CD Μφ were unable to promote wound healing and produced lower levels of HGF as compared to Μφ from HD or UC patients. In particular, Μφ from CD in active phase (ACD) exhibited the weakest repair function, but this defect was rescued if rh- GM-CSF was added during the differentiation of PBMCs. Interestingly, IMACs from HD promoted wound healing and produced HGF.Conclusion: We demonstrated that CD Μφ, unlike HD or UC Μφ, were defective in promoting wound healing, in particular if coming from an ACD. This deficient pro-repair function was related to a lower production of HGF. IMACs from HD colonic mucosa induced wound healing, confirming the results obtained with Μφ. Our results are in keeping with the current theory of CD as an innate immunodeficiency. In this context, Μφ may be responsible for the mucosal repair defects observed in CD patients and for the subsequent chronic activation of the adaptive immune response.