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1.
Acta Psychiatr Scand ; 142(5): 394-401, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32677051

RESUMO

OBJECTIVE: Ketamine's effects on different dimensions of depressive symptomatology, including typical/melancholic and atypical depression, remain largely unknown. This study examined the effects of a single intravenous dose of ketamine on general depressive symptoms (measured using the Montgomery-Asberg Depression Rating Scale (MADRS), typical/melancholic symptoms (measured using the MADRS5), and atypical symptoms (measured using the Scale for Atypical Symptoms (SAS)). METHODS: Data from 68 participants with treatment-resistant major depressive disorder (MDD) or bipolar depression were pooled from three separate, double-blind, placebo-controlled, crossover studies investigating ketamine's efficacy in depression. MDD participants were unmedicated; bipolar participants received therapeutic-dose lithium or valproate. Clinical symptoms were collected preinfusion and up to 14 days postinfusion. Effect sizes were calculated for days 1 and 3 postinfusion. The primary measures of interest for this exploratory analysis were total MADRS, MADRS5, and SAS scores. Individual symptoms were also analyzed in an exploratory manner. RESULTS: Scores improved significantly at Day 1 postinfusion (MADRS: Cohen's d = 0.64; MADRS5: Cohen's d = 0.61; SAS: Cohen's d = 0.41) and continued to be significantly improved over placebo at Day 3 (MADRS: Cohen's d = 0.49; MADRS5: Cohen's d = 0.43; SAS: Cohen's d = 0.39). Effect sizes were greater for typical/melancholic than atypical symptoms at Day 1 postinfusion. CONCLUSION: Ketamine appears to effectively treat both the typical/melancholic and atypical symptoms of depression, but may have early preferential effects for the former.


Assuntos
Transtorno Depressivo Maior , Transtorno Depressivo Resistente a Tratamento , Ketamina , Depressão , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Método Duplo-Cego , Humanos , Resultado do Tratamento
2.
Mol Psychiatry ; 23(7): 1626-1631, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28555075

RESUMO

Patients with major depressive disorder (MDD) have clinically relevant, significant decreases in bone mineral density (BMD). We sought to determine if predictive markers of bone inflammation-the osteoprotegerin (OPG)-RANK-RANKL system or osteopontin (OPN)-play a role in the bone abnormalities associated with MDD and, if so, whether ketamine treatment corrected the abnormalities. The OPG-RANK-RANKL system plays the principal role in determining the balance between bone resorption and bone formation. RANKL is the osteoclast differentiating factor and diminishes BMD. OPG is a decoy receptor for RANKL, thereby increasing BMD. OPN is the bone glue that acts as a scaffold between bone tissues matrix composition to bind them together and is an important component of bone strength and fracture resistance. Twenty-eight medication-free inpatients with treatment-resistant MDD and 16 healthy controls (HCs) participated in the study. Peripheral bone marker levels and their responses to IV ketamine infusion in MDD patients and HCs were measured at four time points: at baseline, and post-infusion at 230 min, Day 1, and Day 3. Patients with MDD had significant decreases in baseline OPG/RANKL ratio and in plasma OPN levels. Ketamine significantly increased both the OPG/RANKL ratio and plasma OPN levels, and significantly decreased RANKL levels. Bone marker levels in HCs remained unaltered. We conclude that the OPG-RANK-RANKL system and the OPN system play important roles in the serious bone abnormalities associated with MDD. These data suggest that, in addition to its antidepressant effects, ketamine also has a salutary effect on a major medical complication of depressive illness.


Assuntos
Transtorno Depressivo Maior/tratamento farmacológico , Ketamina/farmacologia , Ketamina/uso terapêutico , Adulto , Biomarcadores , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/anormalidades , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteopontina/fisiologia , Osteoprotegerina/fisiologia , Ligante RANK/fisiologia , Receptor Ativador de Fator Nuclear kappa-B/fisiologia
3.
Int J Obes (Lond) ; 42(3): 384-390, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29381148

RESUMO

OBJECTIVE: Body mass index (BMI) is commonly used to assess obesity, which is associated with numerous diseases and negative health outcomes. BMI has been shown to be a heritable, polygenic trait, with close to 100 loci previously identified and replicated in multiple populations. We aim to replicate known BMI loci and identify novel associations in a trans-ethnic study population. SUBJECTS: Using eligible participants from the Population Architecture using Genomics and Epidemiology consortium, we conducted a trans-ethnic meta-analysis of 102 514 African Americans, Hispanics, Asian/Native Hawaiian, Native Americans and European Americans. Participants were genotyped on over 200 000 SNPs on the Illumina Metabochip custom array, or imputed into the 1000 Genomes Project (Phase I). Linear regression of the natural log of BMI, adjusting for age, sex, study site (if applicable), and ancestry principal components, was conducted for each race/ethnicity within each study cohort. Race/ethnicity-specific, and combined meta-analyses used fixed-effects models. RESULTS: We replicated 15 of 21 BMI loci included on the Metabochip, and identified two novel BMI loci at 1q41 (rs2820436) and 2q31.1 (rs10930502) at the Metabochip-wide significance threshold (P<2.5 × 10-7). Bioinformatic functional investigation of SNPs at these loci suggests a possible impact on pathways that regulate metabolism and adipose tissue. CONCLUSION: Conducting studies in genetically diverse populations continues to be a valuable strategy for replicating known loci and uncovering novel BMI associations.


Assuntos
Índice de Massa Corporal , Grupos Raciais/genética , Grupos Raciais/estatística & dados numéricos , Estudo de Associação Genômica Ampla , Genômica , Humanos , Polimorfismo de Nucleotídeo Único/genética
6.
Nat Genet ; 1(5): 333-6, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1363815

RESUMO

The gene encoding the granulocyte macrophage colony stimulating factor receptor alpha subunit (CSF2RA) has previously been mapped to the pseudoautosomal region of the human sex chromosomes. In contrast, we report that the murine locus, Csf2ra, maps to an autosome in the laboratory mouse. By in situ hybridization and genetic mapping, Csf2ra maps at telomeric band D2 of mouse chromosome 19. This first instance of a pseudoautosomal locus in human being autosomal in mouse, indicates incomplete conservation between the human and mouse X chromosomes and suggests that the genetic content of the pseudoautosomal region may differ between species of eutherian mammals due to chromosomal rearrangements.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Cromossomo X , Animais , Bandeamento Cromossômico , Mapeamento Cromossômico , Cruzamentos Genéticos , Feminino , Humanos , Hibridização In Situ , Substâncias Macromoleculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Muridae , Polimorfismo de Fragmento de Restrição , Telômero
7.
Front Cardiovasc Med ; 10: 1276321, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38028437

RESUMO

Background: Myocarditis is a condition that can have severe adverse outcomes and lead to sudden cardiac death if remaining undetected. This study tested the capability of cardiac magnetic field mapping to detect patients with clinically suspected myocarditis. This could open up the way for rapid, non-invasive, and cost-effective screening of suspected cases before a gold standard assessment via endomyocardial biopsy. Methods: Historical cardiac magnetic field maps (n = 97) and data from a state-of-the-art magnetocardiography device (n = 30) were analyzed using the Kullback-Leibler entropy (KLE) for dimensionality reduction and topological quantification. Linear discriminant analysis was used to discern between patients with ongoing myocarditis and healthy controls. Results: The STT segment of a magnetocardiogram, i.e., the section between the end of the S wave and the end of the T wave, was best suited to discern both groups. Using a 250-ms excerpt from the onset of the STT segment gave a reliable classification between the myocarditis and control group for both historic data (sensitivity: 0.83, specificity: 0.85, accuracy: 0.84) and recent data (sensitivity: 0.69, specificity: 0.88, accuracy: 0.80) using the KLE to quantify the topology of the cardiac magnetic field map. Conclusion: The implementation based on KLE can reliably distinguish between clinically suspected myocarditis patients and healthy controls. We implemented an automatized feature selection based on LDA to replace the observer-dependent manual thresholding in previous studies.

8.
Cytogenet Genome Res ; 136(1): 69-74, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22188666

RESUMO

Unlike other Pacific salmon, sockeye salmon (Oncorhynchus nerka) have an X(1)X(2)Y sex chromosome system, with females having a diploid chromosome number of 2n = 58 and males 2n = 57 in all populations examined. To determine the origin of the sockeye Y chromosome, we mapped microsatellite loci from the rainbow trout (O. mykiss; OMY) genetic map, including those found on the Y chromosomes of related species, in kokanee (i.e. non-anadromous sockeye) crosses. Results showed that 3 microsatellite loci from the long arm of rainbow trout chromosome 8 (OMY8q), linked to SEX (the sex-determining locus) in coho salmon (O. kisutch), are also closely linked to SEX in the kokanee crosses. We also found that 3 microsatellite loci from OMY2q are linked to those markers from OMY8q and SEX in kokanee, with both linkage groups fused to form the neo-Y. These results were confirmed by physical mapping of BAC clones containing microsatellite loci from OMY8q and OMY2q to kokanee chromosomes using fluorescence in situ hybridization. The fusion of OMY2q to the ancestral Y may have resolved sexual conflict and, in turn, may have played a large role in the divergence of sockeye from a shared ancestor with coho.


Assuntos
Cromossomos de Mamíferos , Ligação Genética , Oncorhynchus kisutch/genética , Oncorhynchus mykiss/genética , Salmão/genética , Cromossomo Y , Animais , Mapeamento Cromossômico/métodos , Feminino , Hibridização in Situ Fluorescente/métodos , Masculino , Repetições de Microssatélites/genética , Filogenia , Processos de Determinação Sexual
9.
Ultrasound Obstet Gynecol ; 39(4): 444-51, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21728205

RESUMO

OBJECTIVE: To evaluate the utility of magnetic resonance imaging (MRI) in diagnosing structural injury in primiparous women at risk for pelvic floor injury. METHODS: This was an observational study of 77 women who underwent 3T MRI after delivery. Women were operationally defined as high risk (n = 45) for levator ani muscle tears (risk factors: second-stage labor > 150 min or < 30 min, anal sphincter tear, forceps, maternal age > 35 years and birth weight > 4000 g) or low risk (n = 32): vaginally delivered without these risk factors (n = 12); delivered by Cesarean section after second-stage labor > 150 min (n = 14) or delivered by Cesarean section without labor (n = 6). All women were imaged using fluid-sensitive MRI sequences. Two musculoskeletal radiologists reviewed images for bone marrow edema, fracture, pubic symphysis measurements and levator ani tear. RESULTS: MRI showed pubic bone fractures in 38% of women at high risk for pelvic floor injury and in 13% of women at low risk for pelvic floor injury (χ(2) (3) = 9.27, P = 0.03). Levator ani muscle tears were present in 44% of the high-risk women and in 9% of the low-risk women (χ(2) (3) = 11.57, P = 0.010). Bone marrow edema in the pubic bones was present in 61% of women studied across delivery categories. Complex patterns of injury included combinations of bone marrow edema, fractures, levator ani tears and pubic symphysis injuries. No MRI-documented injuries were present in 18% of women at high risk and 44% at low risk for pelvic floor injury (χ(2) (1) = 6.2, P = 0.013). CONCLUSIONS: Criteria identifying primiparous women at risk for pelvic floor injury can predict increased risk of bone and soft tissue changes at the pubic symphysis. Fluid-sensitive MRI has utility for differential diagnosis of structural injury in postpartum women.


Assuntos
Doenças da Medula Óssea/diagnóstico , Parto Obstétrico/efeitos adversos , Edema/diagnóstico , Imageamento por Ressonância Magnética , Diafragma da Pelve/lesões , Osso Púbico/lesões , Adulto , Doenças da Medula Óssea/patologia , Cesárea , Diagnóstico Diferencial , Edema/patologia , Feminino , Humanos , Recém-Nascido , Paridade , Diafragma da Pelve/patologia , Gravidez , Osso Púbico/patologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
10.
Nat Med ; 1(7): 674-80, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7585150

RESUMO

We and others have postulated that a constant number of T lymphocytes is normally maintained without regard to CD4+ or CD8+ phenotype ('blind' T-cell homeostasis). Here we confirm essentially constant T-cell levels (despite marked decline in CD4+ T cells and increase in CD8+ T cells) in homosexual men with incident human immunodeficiency virus, type 1 (HIV-1), infection who remained free of acquired immunodeficiency syndrome (AIDS) for up to eight years after seroconversion. In contrast, seroconverters who developed AIDS exhibited rapidly declining T cells (both CD4+ and CD8+) for approximately two years before AIDS, independent of the time between seroconversion and AIDS, suggesting that homeostasis failure is an important landmark in HIV disease progression. Given the high rate of T-cell turnover in HIV-1 infection, blind T-cell homeostasis may contribute to HIV pathogenesis through a CD8+ T lymphocytosis that interferes with regeneration of lost CD4+ T cells.


Assuntos
Síndrome da Imunodeficiência Adquirida/fisiopatologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Infecções por HIV/fisiopatologia , HIV-1 , Hematopoese , Contagem de Linfócitos , Síndrome da Imunodeficiência Adquirida/imunologia , Relação CD4-CD8 , Estudos de Coortes , Progressão da Doença , Infecções por HIV/imunologia , Soropositividade para HIV/imunologia , Homeostase , Homossexualidade , Humanos , Linfocitose/etiologia , Masculino , Fatores de Tempo
11.
Nat Med ; 4(9): 1025-31, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9734395

RESUMO

Accelerated atherosclerosis in patients with diabetes is a major cause of their morbidity and mortality, and it is unresponsive to therapy aimed at restoring relative euglycemia. In hyperglycemia, nonenzymatic glycation and oxidation of proteins and lipids results in the accumulation of irreversibly formed advanced glycation endproducts. These advanced glycation endproducts engage their receptor in cells of the blood vessel wall, thereby activating mechanisms linked to the development of vascular lesions. We report here a model of accelerated and advanced atherosclerosis in diabetic mice deficient for apolipoprotein E. Treatment of these mice with the soluble extracellular domain of the receptor for advanced glycation endproducts completely suppressed diabetic atherosclerosis in a glycemia- and lipid-independent manner. These findings indicate interaction between the advanced glycation endproducts and their receptor is involved in the development of accelerated atherosclerosis in diabetes, and identify this receptor as a new therapeutic target in diabetic macrovascular disease.


Assuntos
Arteriosclerose/tratamento farmacológico , Diabetes Mellitus Experimental/complicações , Angiopatias Diabéticas/tratamento farmacológico , Produtos Finais de Glicação Avançada/metabolismo , Receptores Imunológicos/uso terapêutico , Animais , Arteriosclerose/etiologia , Linhagem Celular , Diabetes Mellitus Experimental/fisiopatologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Solubilidade , Spodoptera , Estreptozocina
12.
Nat Med ; 2(4): 405-11, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8597949

RESUMO

Major histocompatibility complex (MHC) genes (HLA in humans) regulate the immune response to foreign antigens. Molecular and serologic techniques were used to identify products of HLA class I, class II and transporter (TAP) genes (also part of the MHC) in homosexual seroconverters to human immunodeficiency virus type 1 (HIV-1). Comprehensive statistical analysis produced an HLA profile that predicted time from HIV-1 infection to the onset of AIDS. The profile was developed in a cohort of 139 men and evaluated in a second unrelated cohort of 102 men. In the evaluation cohort, the profile discriminated a sixfold difference between groups with the shortest and longest times to AIDS (P = 0.001). These findings support current theory about control of antigen processing by HLA genes and have implications for immunopathogenesis of HIV-1 and other infections.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Infecções por HIV/genética , HIV-1/isolamento & purificação , Complexo Principal de Histocompatibilidade/genética , Estudos de Coortes , Ligação Genética , Infecções por HIV/imunologia , Infecções por HIV/mortalidade , Antígenos de Histocompatibilidade Classe I/análise , Antígenos de Histocompatibilidade Classe II/análise , Humanos , Masculino , Análise de Sobrevida
13.
Eur J Cardiovasc Nurs ; 20(2): 160­166, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33611341

RESUMO

BACKGROUND: Traditionally, physical movement has been limited for cardiac surgery patients, up to 12-weeks post-operatively. Patients are asked to use "standard sternal precautions," restricting their arm movement, and thereby limiting stress on the healing sternum. AIM: To compare return to function, pain/discomfort, wound healing, use of pain medication and antibiotics, and post-operative length of hospital stay in cardiac surgery patients having median sternotomy who used standard sternal precautions or Keep Your Move in the Tube movement protocols post-operatively. METHODS: A quasi-experimental design was used (100 standard sternal precautions and 100 Keep Your Move in the Tube patients). Patients were followed in person or by telephone over a period of 12-weeks postoperatively. Outcomes were measured at day 7, as well as weeks 4, 8, and 12 weeks. RESULTS: The majority of participants (77% in each group) were male and had coronary artery bypass graft surgery (66% standard sternal precautions and 72% Keep Your Move in the Tube). Univariate analysis revealed the standard sternal precautions group had lesser ability to return to functional activities than the Keep Your Move in the Tube group (p<0.0001) over time. This difference was minimized however, by week 12. Multivariate analysis revealed that increasing age, body mass index, and female sex were associated with greater functional impairment over time, but no difference between standard sternal precautions and Keep Your Move in the Tube groups. CONCLUSIONS: Keep Your Move in the Tube, a novel patient-oriented movement protocol, has potential for cardiac surgery patients to be more confident and comfortable in their recovery.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Esternotomia , Ponte de Artéria Coronária , Feminino , Humanos , Masculino , Período Pós-Operatório , Esterno , Infecção da Ferida Cirúrgica
14.
J Exp Med ; 164(1): 251-62, 1986 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-3014035

RESUMO

125I-labeled recombinant human GM-CSF was used to identify and characterize receptors specific for this lymphokine on both a mature primary cell, human neutrophils, and on the undifferentiated promyelomonocytic leukemia cell line, HL-60. Human GM-CSF also bound to primary human monocytes and to the myelogenous leukemia cell line, KG-1, but not to any of the murine cells known to express the murine GM-CSF receptor. In addition, although some murine T lymphomas can express the GM-CSF receptor, none of the human cell lines of T cell lineage that we examined bound iodinated human GM-CSF. Binding to all cell types was specific and saturable. Equilibrium binding studies revealed that on all cell types examined, GM-CSF bound to a single class of high affinity receptor (100-500 receptors per cell) with a Ka of 10(9)-10(10)/M. More extensive characterization with neutrophils and HL-60 cells showed that in both cases, binding of GM-CSF was rapid at 37 degrees C with a slow subsequent dissociation rate that exhibited marked biphasic kinetics. Among a panel of lymphokines and growth hormones, only human GM-CSF could compete for binding of human 125I-GM-CSF to these cells. GM-CSF can not only stimulate the proliferation and differentiation of granulocyte/macrophage precursor cells, but can modulate the functional activity of mature granulocytes and macrophages as well. No significant differences in the kinetic parameters of receptor binding were seen between mature neutrophils and the undifferentiated promyelocytic leukemia cell line HL-60, indicating that maturation-specific responses to GM-CSF are not mediated by overt changes in the binding characteristics of the hormone for its receptor.


Assuntos
Granulócitos/metabolismo , Macrófagos/metabolismo , Proteínas de Membrana/análise , Receptores de Superfície Celular/análise , Animais , Autorradiografia , Linhagem Celular , Eletroforese em Gel de Poliacrilamida , Humanos , Leucemia Mieloide/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Neutrófilos/metabolismo , Receptores de Fator Estimulador de Colônias , Proteínas Recombinantes
15.
J Exp Med ; 166(2): 476-88, 1987 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-3496417

RESUMO

125I-labeled recombinant human B cell stimulatory factor 1 (BSF-1) was used to characterize receptors specific for this lymphokine on in vitro cell lines representing human B, T, and hematopoietic lineages, as well as on adherent cell lines of epithelial and endothelial origin, and on primary human gingival fibroblasts. BSF-1 binding was extremely rapid and saturable at both 4 and 37 degrees C, with a slow dissociation rate. On all human cell types examined, BSF-1 bound to a single class of high-affinity receptor (less than 3,000 receptors per cell) with a Ka of 0.5-1.0 X 10(10)/M. Human BSF-1 also bound to cell lines of simian but not murine origin. Comparison of kinetic characteristics obtained with a yeast-derived hyperglycosylated form of BSF-1 (Mr 60,000) and N-glycanase-treated, sugar-free BSF-1 (Mr 15,000) showed no significant differences. Among a panel of lymphokines and growth hormones, only unlabeled human BSF-1 was able to compete for the binding of 125I-labeled human BSF-1. Affinity crosslinking experiments resulted in the identification on both Raji cells and on primary human gingival fibroblasts of a receptor subunit with an average Mr of 139,000. These studies show that the BSF-1 receptor on human cells has an extremely broad cellular distribution, while further supporting the notion that the ability of BSF-1 to mediate a spectrum of biological activities cannot be accounted for by overt differences in the receptor for this lymphokine on different cell lineages.


Assuntos
Gengiva/imunologia , Receptores Mitogênicos , Linfócitos B/metabolismo , Linhagem Celular , Fibroblastos/análise , Gengiva/análise , Gengiva/citologia , Substâncias de Crescimento/metabolismo , Humanos , Interleucina-4 , Cinética , Linfocinas/metabolismo , Linfoma/imunologia , Receptores de Interleucina-4 , Receptores Mitogênicos/análise , Proteínas Recombinantes/metabolismo , Linfócitos T/metabolismo , Distribuição Tecidual
16.
J Exp Med ; 171(4): 1073-89, 1990 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2324686

RESUMO

A murine cell line (IxN/2b) absolutely dependent upon exogenous IL-7 for continued growth has been obtained that expresses lymphoid precursor and class I MHC antigens and also contains a rearranged mu heavy chain. This cell line has been used to define the binding and structural characteristics of the murine IL-7 receptor using 125I-labeled recombinant murine IL-7. 125I-IL-7 binding to IxN/2b cell was rapid and saturable at both 4 degrees and 37 degrees C. Equilibrium binding studies produced curvilinear Scatchard plots at both temperatures with high and low affinity Ka values of approximately 1 x 10(10) M-1 and 4 x 10(8) M-1, respectively, and a total of 2,000-2,500 IL-7 binding sites expressed per cell. Experiments measuring inhibition of binding of 125I-IL-7 by unlabeled IL-7 also produced data consistent with the existence of two classes of IL-7 receptors. Evidence concerning the possible molecular nature of two classes of IL-7 receptors was provided by dissociation kinetics and affinity crosslinking experiments. The dissociation rate of 125I-IL-7 was markedly increased when measured in the presence of unlabeled IL-7 at both 37 degrees and 4 degrees C, which is diagnostic of a receptor population displaying negative cooperativity. Crosslinking studies showed that under both reducing and nonreducing conditions, the major crosslinked species observed corresponded to a receptor size of 75-79 kD while a less intense higher molecular mass crosslinked species was also seen which corresponded to a receptor size approximately twice as large (159-162 kD). Both types of experiments suggest that the IL-7 receptor may form noncovalently associated dimers in the membrane. The IL-7 receptor was expressed on pre-B cells, but not detected on several murine B cell lines or primary mature B cells. It was also expressed on murine thymocytes, some T lineage cell lines, and on bone marrow-derived macrophage. All cells binding 125I-IL-7 exhibited curvilinear Scatchard plots. No cytokines or growth factors tested were able to inhibit binding of 125I-IL-7 to its receptor. These results define the initial binding and structural characteristics, and the cellular distribution, of the murine IL-7 receptor.


Assuntos
Interleucina-7/farmacologia , Receptores Imunológicos/fisiologia , Animais , Antígenos de Superfície/análise , Ligação Competitiva , Linhagem Celular , Membrana Celular/imunologia , Citometria de Fluxo , Humanos , Interleucina-7/isolamento & purificação , Interleucina-7/metabolismo , Interleucinas/farmacologia , Cinética , Receptores Imunológicos/efeitos dos fármacos , Receptores de Interleucina-7 , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Células Tumorais Cultivadas/imunologia
17.
J Exp Med ; 167(3): 988-1002, 1988 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-3258354

RESUMO

We have used a biological assay system we developed to biochemically purify a previously uncharacterized murine lymphopoietic growth factor designated lymphopoietin 1 (LP-1). This factor is capable of stimulating the proliferation and extended maintenance of precursor cells of the B lineage. A stromal cell line producing LP-1 was established after transfection of primary stromal cultures with a plasmid encoding the transforming genes of SV40. This factor was purified to a single 25-kD species from the culture supernatant of an adherent stromal cell line. This material acts on immature lymphocytes, it binds to specific receptors on cells, and is distinct from previously described hematopoietic factors. LP-1 has been purified some 10(7)-fold with an overall recovery of 35%. The purified protein exhibits a specific activity of approximately 4 X 10(6) U/micrograms of protein and is active at a half-maximal concentration of 10(-13) M.


Assuntos
Linfócitos B/citologia , Medula Óssea/análise , Substâncias de Crescimento/isolamento & purificação , Células-Tronco Hematopoéticas/efeitos dos fármacos , Animais , Células da Medula Óssea , Divisão Celular/efeitos dos fármacos , Células Clonais/análise , Substâncias de Crescimento/farmacologia , Células-Tronco Hematopoéticas/citologia , Camundongos
18.
J Exp Med ; 171(3): 861-73, 1990 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2307934

RESUMO

IL-4, a pleiotropic cytokine produced by T lymphocytes, plays an important role in immune responsiveness by regulating proliferation and differentiation of a variety of lymphoid and myeloid cells via binding to high affinity receptors. In this report we describe the isolation and functional expression of a human IL-4-R cDNA. When transfected into COS-7 cells, the cDNA encodes a 140-kD cell-surface protein. After transfection into a murine T cell line, the cDNA encodes a protein that binds human IL-4 with high affinity and can confer responsiveness to human IL-4. The predicted extracellular domain of the IL-4-R exhibits significant amino acid sequence homology with the beta subunit of the IL-2-R (p75), and the receptors for IL-6, erythropoietin, and prolactin. These receptors comprise a novel superfamily with extracellular domains characterized by four conserved cysteine residues and a double tryptophan-serine (WSXWS) motif located proximal to the transmembrane region.


Assuntos
Interleucina-4/metabolismo , Receptores Mitogênicos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA/análise , Humanos , Interleucina-4/farmacologia , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/análise , Receptores de Interleucina-4 , Receptores Mitogênicos/análise , Transdução de Sinais
19.
J Exp Med ; 172(6): 1559-70, 1990 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-2147944

RESUMO

We report the isolation from a placental library, of two cDNAs that can encode high affinity receptors for granulocyte colony-stimulating factor (G-CSF) when expressed in COS-7 cells. The cDNAs are predicted to encode integral membrane proteins of 759 and 812 amino acids in length. The predicted extracellular and membrane spanning sequences of the two clones are identical, as are the first 96 amino acids of their respective cytoplasmic regions. Different COOH termini of 34 or 87 residues are predicted for the two cDNAs, due apparently to alternate splicing. The receptor with the longer cytoplasmic domain is the closest human homologue of the murine G-CSF receptor recently described by Fukunaga et al. (Fukunaga, R., E. Ishizaka-Ikeda, Y. Seto, and S. Nagata. 1990. Cell. 61:341). A hybridization probe derived from the placental G-CSF receptor cDNA detects a approximately 3-kb transcript in RNAs isolated from placenta and a number of lymphoid and myeloid cells. The extracellular region of the G-CSF receptors is composed of four distinct types of structural domains, previously recognized in other cell surface proteins. In addition to the two domains of the HP receptor family-defining region (Patthy, L. 1990. Cell. 61:13) it incorporates one NH2-terminal Ig-like domain, and three additional repeats of fibronectin type III-like domains. The presence of both an NH2-terminal Ig-like domain and multiple membrane-proximal FN3-like domains suggests that the G-CSF receptor may be derived from an ancestral NCAM-like molecule and that the G-CSF receptor may function in some adhesion or recognition events at the cell surface in addition to the binding of G-CSF.


Assuntos
Fibronectinas/genética , Genes de Imunoglobulinas , Receptores de Fator Estimulador de Colônias de Granulócitos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , DNA/genética , DNA/isolamento & purificação , Feminino , Biblioteca Gênica , Humanos , Cinética , Camundongos , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Placenta/metabolismo , Gravidez , Conformação Proteica , Receptores de Fator Estimulador de Colônias de Granulócitos/metabolismo , Proteínas Recombinantes/metabolismo , Homologia de Sequência do Ácido Nucleico
20.
J Exp Med ; 192(5): 659-70, 2000 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-10974032

RESUMO

The cellular receptor for murine thymic stromal lymphopoietin (TSLP) was detected in a variety of murine, but not human myelomonocytic cell lines by radioligand binding. cDNA clones encoding the receptor were isolated from a murine T helper cell cDNA library. TSLP receptor (TSLPR) is a member of the hematopoietin receptor family. Transfection of TSLPR cDNA resulted in only low affinity binding. Cotransfection of the interleukin 7 (IL-7)Ralpha chain cDNA resulted in conversion to high affinity binding. TSLP did not activate cells from IL-7Ralpha(-/)- mice, but did activate cells from gammac(-/)- mice. Thus, the functional TSLPR requires the IL-7Ralpha chain, but not the gammac chain for signaling.


Assuntos
Hematopoese/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Receptores de Citocinas/fisiologia , Receptores de Interleucina-7/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Mapeamento Cromossômico , Clonagem Molecular , Citocinas/farmacologia , Humanos , Interleucina-7/farmacologia , Linfócitos/fisiologia , Masculino , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/análise , Receptores de Citocinas/química , Receptores de Citocinas/genética , Receptores de Interleucina-7/química , Proteínas Recombinantes/química , Transdução de Sinais
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