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1.
Eur J Immunol ; 50(4): 568-580, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31850514

RESUMEN

The pro-inflammatory cytokine IL-17A has been implicated in the immunopathology of inflammatory arthritis. IL-17F bears 50% homology to IL-17A and has recently been suggested to play a role in inflammation. We investigated the induction and cytokine profile of IL-17F+ CD4+ T cells, and how IL-17F may contribute to inflammation. Upon culture of healthy donor CD4+ T cells with IL-1ß, IL-23, anti-CD3, and anti-CD28 mAb, both IL-17A and IL-17F-expressing cells were detected. In comparison to IL-17A+ IL-17F- CD4+ T cells, IL-17F+ IL-17A- and IL-17A+ IL-17F+ CD4+ T cells contained lower proportions of IL-10-expressing and GM-CSF-expressing cells and higher proportions of IFN-γ-expressing cells. Titration of anti-CD28 mAb revealed that strong co-stimulation increased IL-17F+ IL-17A- and IL-17A+ IL-17F+ CD4+ T cell frequencies, whereas IL-17A+ IL-17F- CD4+ T cell frequencies decreased. This was partly mediated via an IL-2-dependent mechanism. Addition of IL-17A, IL-17F, and TNF-α to synovial fibroblasts from patients with inflammatory arthritis resulted in significant production of IL-6 and IL-8, which was reduced to a larger extent by combined blockade of IL-17A and IL-17F than blockade of IL-17A alone. Our data indicate that IL-17A and IL-17F are differentially regulated upon T cell co-stimulation, and that dual blockade of IL-17A and IL-17F reduces inflammation more effectively than IL-17A blockade alone.


Asunto(s)
Artritis Reumatoide/inmunología , Linfocitos T CD4-Positivos/inmunología , Fibroblastos/fisiología , Inflamación/inmunología , Interleucina-17/metabolismo , Membrana Sinovial/patología , Anticuerpos Monoclonales/metabolismo , Antígenos CD28/inmunología , Antígenos CD28/metabolismo , Separación Celular , Células Cultivadas , Citocinas/metabolismo , Citometría de Flujo , Humanos , Interleucina-17/inmunología , Receptor Cross-Talk
2.
Brain ; 143(6): 1731-1745, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32437528

RESUMEN

Autoantibodies against leucine-rich glioma inactivated 1 (LGI1) are found in patients with limbic encephalitis and focal seizures. Here, we generate patient-derived monoclonal antibodies (mAbs) against LGI1. We explore their sequences and binding characteristics, plus their pathogenic potential using transfected HEK293T cells, rodent neuronal preparations, and behavioural and electrophysiological assessments in vivo after mAb injections into the rodent hippocampus. In live cell-based assays, LGI1 epitope recognition was examined with patient sera (n = 31), CSFs (n = 11), longitudinal serum samples (n = 15), and using mAbs (n = 14) generated from peripheral B cells of two patients. All sera and 9/11 CSFs bound both the leucine-rich repeat (LRR) and the epitempin repeat (EPTP) domains of LGI1, with stable ratios of LRR:EPTP antibody levels over time. By contrast, the mAbs derived from both patients recognized either the LRR or EPTP domain. mAbs against both domain specificities showed varied binding strengths, and marked genetic heterogeneity, with high mutation frequencies. LRR-specific mAbs recognized LGI1 docked to its interaction partners, ADAM22 and ADAM23, bound to rodent brain sections, and induced internalization of the LGI1-ADAM22/23 complex in both HEK293T cells and live hippocampal neurons. By contrast, few EPTP-specific mAbs bound to rodent brain sections or ADAM22/23-docked LGI1, but all inhibited the docking of LGI1 to ADAM22/23. After intrahippocampal injection, and by contrast to the LRR-directed mAbs, the EPTP-directed mAbs showed far less avid binding to brain tissue and were consistently detected in the serum. Post-injection, both domain-specific mAbs abrogated long-term potentiation induction, and LRR-directed antibodies with higher binding strengths induced memory impairment. Taken together, two largely dichotomous populations of LGI1 mAbs with distinct domain binding characteristics exist in the affinity matured peripheral autoantigen-specific memory pools of individuals, both of which have pathogenic potential. In human autoantibody-mediated diseases, the detailed characterization of patient mAbs provides a valuable method to dissect the molecular mechanisms within polyclonal populations.


Asunto(s)
Anticuerpos Monoclonales/metabolismo , Autoanticuerpos/inmunología , Péptidos y Proteínas de Señalización Intracelular/inmunología , Proteínas ADAM/metabolismo , Animales , Anticuerpos Monoclonales/inmunología , Autoanticuerpos/sangre , Autoanticuerpos/metabolismo , Autoantígenos/metabolismo , Encéfalo/metabolismo , Epítopos/inmunología , Células HEK293 , Hipocampo/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Encefalitis Límbica/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Unión Proteica/inmunología , Dominios Proteicos/inmunología
3.
Eur J Immunol ; 45(4): 1116-28, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25545270

RESUMEN

The costimulatory receptor OX40 is expressed on activated T cells and regulates T-cell responses. Here, we show the efficacy and mechanism of action of an OX40 blocking antibody using the chronic house dust mite (HDM) mouse model of lung inflammation and in vitro HDM stimulation of cells from HDM allergic human donors. We have demonstrated that OX40 blockade leads to a reduction in the number of eosinophils and neutrophils in the lavage fluid and lung tissue of HDM sensitized mice. This was accompanied by a decrease in activated and memory CD4(+) T cells in the lungs and further analysis revealed that both the Th2 and Th17 populations were inhibited. Improved lung function and decreased HDM-specific antibody responses were also noted. Significantly, efficacy was observed even when anti-OX40 treatment was delayed until after inflammation was established. OX40 blockade also inhibited the release of the Th2 cytokines IL-5 and IL-13 from cells isolated from HDM allergic human donors. Altogether, our data provide evidence of a role of the OX40/OX40L pathway in ongoing allergic lung inflammation and support clinical studies of a blocking OX40 antibody in Th2 high severe asthma patients.


Asunto(s)
Anticuerpos Bloqueadores/farmacología , Neumonía/inmunología , Pyroglyphidae/inmunología , Receptores OX40/metabolismo , Células Th2/inmunología , Animales , Asma/tratamiento farmacológico , Asma/inmunología , Hiperreactividad Bronquial/inmunología , Líquido del Lavado Bronquioalveolar/citología , Modelos Animales de Enfermedad , Eosinófilos/inmunología , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina G/sangre , Memoria Inmunológica/inmunología , Interleucina-13/metabolismo , Interleucina-5/metabolismo , Pulmón/citología , Recuento de Linfocitos , Ratones , Ratones Endogámicos BALB C , Neutrófilos/inmunología , Neumonía/tratamiento farmacológico , Neumonía/prevención & control , Receptores OX40/antagonistas & inhibidores , Células Th17/inmunología
4.
Am J Bot ; 103(3): 553-67, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26872491

RESUMEN

PREMISE OF THE STUDY: Whenever more pollen grains arrive on stigmas than necessary to fertilize ovules, sexual selection is possible. However, the role of sexual selection remains controversial, in part because of lack of evidence on genetic bases of traits and the response of relevant characters to selection. METHODS: In an experiment with Raphanus sativus, we selected on tendency to sire seeds in the stylar or basal regions of fruits. This character is likely related to pollen tube growth rate, and seed position affects rates of abortion and seed predation. We measured differences among families in seed siring and related characters and evaluated responses to selection. KEY RESULTS: All replicates showed strong effects of pollen donor family on proportion of seeds sired per fruit in mixed pollinations. Most also showed effects of pollen donor family on number of pollen grains per flower and pollen diameter. Two of four replicates showed a response to selection on position of seeds sired. In responding replicates, we found trade-offs in pollen grain size and number; plants with larger pollen grains sired more seeds in the basal region. CONCLUSIONS: Our data suggest a genetic basis for pollen donor ability to sire seeds in competition. The significant response to selection in two replicates shows that position of seeds sired can respond to selection. Thus, all components for sexual selection to occur and affect traits are present. Variation in results among replicates might be due to changes in greenhouse conditions. Environmental effects may contribute to the maintenance of variation in these fitness-related characters.


Asunto(s)
Evolución Biológica , Raphanus/fisiología , Selección Genética , Análisis de Varianza , Distribución de Chi-Cuadrado , Modelos Biológicos , Polen/fisiología , Polinización , Semillas/fisiología
5.
Ecol Evol ; 13(9): e10479, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37664494

RESUMEN

Understanding the effect of the environment on trait variation is critical for ecologically and economically important plants. Here, we asked whether differences in soil moisture are a source of variation in Sahara mustard (Brassica tournefortii). We subjected common garden populations of plants derived from native, invasive, and landrace sources (ranges) to varying water addition treatments. Using principal component analysis, we generated composite variables of life history traits for ANCOVA tests and plotted norms of reaction. Planting time was included as a covariate because we observed differences in seedling emergence despite efforts to standardize germination. We also examined the population coefficient of variation of individual traits (plasticity) and the association of trait CVs with fitness. The amount of plasticity varied but was inconsistent among range sources for all composite traits. Planting time did not affect treatments, but plants from different ranges responded differently to variable planting times. With a surplus of water, plants derived from native and invasive populations plateaued in vegetative trait values but showed a continuous linear increase in reproductive trait values. Possibly as a result of domestication, moderate and high water treatments in landrace plants caused plateaus in composite trait values for flowering phenology, seed count, plant size, and branching. The ecological breadth shown by our plants is likely due to drought tolerance that evolved in Brassica tournefortii source populations.

6.
Oecologia ; 169(1): 73-84, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22068319

RESUMEN

Variation in freezing severity is hypothesized to have influenced the distribution and evolution of the warm desert evergreen genus Larrea. If this hypothesis is correct, performance and survival of species and populations should vary predictably along gradients of freezing severity. If freezing environment changes in the future, the ability of Larrea to adapt will depend on the structure of variation for freezing resistance within populations. To test whether freezing responses vary among and within Larrea populations, we grew maternal families of seedlings from high and low latitude L. divaricata and high latitude L. tridentata populations in a common garden. We measured survival, projected plant area and dark-adapted chlorophyll fluorescence (F (v) /F (m)) before and after cold acclimation and for 2 weeks following a single freeze. We detected significant variation in freezing resistance among species and populations. Maternal family lines differed significantly in their responses to cold acclimation and/or freezing for two out of the three populations: among L. tridentata maternal families and among low latitude L. divaricata maternal families. There were no significant differences across maternal families of high latitude L. divaricata. Our results indicate that increased freezing resistance in high latitude populations likely facilitated historical population expansion of both species into colder climates, but this may have occurred to a greater extent for L. tridentata than for L. divaricata. Differences in the structure of variation for cold acclimation and freezing responses among populations suggest potential differences in their ability to evolve in response to future changes in freezing severity.


Asunto(s)
Clima , Congelación , Larrea/fisiología , Plantones/fisiología , Estrés Fisiológico , Aclimatación , Clorofila/metabolismo , Larrea/crecimiento & desarrollo
7.
Sex Plant Reprod ; 23(4): 325-36, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20563606

RESUMEN

Although increases in atmospheric [CO(2)] are known to affect plant physiology, growth and reproduction, understanding of these effects is limited because most studies of reproductive consequences focus solely on female function. Therefore, we examined the effects of CO(2) enrichment on male function in the annual Raphanus sativus. Pollen donors grown under elevated [CO(2)] initially sired a higher proportion of seeds per fruit than ambient [CO(2)]-grown plants when each was tested against two different standard competitors; however, by the end of the 5-month experiment, these pollen donors sired fewer seeds than ambient [CO(2)]-grown plants and produced a lower proportion of viable pollen grains. The results of this experiment confirm that elevated [CO(2)] can alter reproductive success. Additionally, the change in response to elevated [CO(2)] over time varied among pollen donor families; thus, changes in [CO(2)] could act as a selective force on this species.


Asunto(s)
Dióxido de Carbono/metabolismo , Polen/crecimiento & desarrollo , Raphanus/metabolismo , Ecosistema , Polen/metabolismo , Raphanus/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Semillas/metabolismo
8.
Ann Bot ; 105(1): 7-22, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19875519

RESUMEN

BACKGROUND: Over a season, plant condition, amount of ongoing reproduction and biotic and abiotic environmental factors vary. As flowers age, flower condition and amount of pollen donated and received also vary. These internal and external changes are significant for fitness if they result in changes in reproduction and mating. SCOPE: Literature from several fields was reviewed to provide a picture of the changes that occur in plants and flowers that can affect mating over a season. As flowers age, both the entire flower and individual floral whorls show changes in appearance and function. Over a season, changes in mating often appear as alteration in seed production vs. pollen donation. In several species, older, unpollinated flowers are more likely to self. If flowers are receiving pollen, staying open longer may increase the number of mates. In wild radish, for which there is considerable information on seed paternity, older flowers produce fewer seeds and appear to discriminate less among pollen donors. Pollen donor performance can also be linked to maternal plant age. Different pollinators and mates are available across the season. Also in wild radish, maternal plants appear to exert the most control over paternity when they are of intermediate age. CONCLUSIONS: Although much is known about the characters of plants and flowers that can change over a season, there is less information on the effects of age on mating. Several studies document changes in self-pollination over time, but very few, other than those on wild radish, consider more subtle aspects of differential success of pollen donors over time.


Asunto(s)
Polinización/fisiología , Raphanus/fisiología , Estaciones del Año , Color , Flores/anatomía & histología , Flores/crecimiento & desarrollo , Flores/fisiología , Polen/fisiología , Raphanus/embriología , Raphanus/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Factores de Tiempo
9.
Ecol Evol ; 9(23): 13127-13141, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31871634

RESUMEN

Varying environments can result in different patterns of adaptive phenotypes. By performing a common greenhouse experiment, we identified phenotypic differentiation on phenology, leaf morphology, branch architecture, size, and reproduction, among native, invasive, and landrace ranges of Brassica tournefortii. We first compared trait means and fitness functions among ranges, then we analyzed how trait means and selection strength of populations respond to varying aridity. Most traits varied such that landrace > invasive > native. Excluding reproduction, which was positively selected, most trait PCs experienced nonlinear selection in the native range but frequently shifted to directional selection in invasive and/or landrace ranges. The absence of strong clines for trait means in landrace and invasive populations suggest that agricultural practices and novel environments in source locations affected adaptive potential. Selection strength on faster reproductive phenology (negative directional) and leaf margin trait (disruptive) PCs coincided with increasing moisture. In native populations, higher aridity was associated with more days to reproduction, but landrace and invasive populations show stable mean time to reproduction with increasing moisture. A stable adaptive trait can increase range expansion in the invasive range, but stability can be beneficial for future harvest of B. tournefortii seed crops in the face of climate change.

10.
AoB Plants ; 10(3): 030, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29869642

RESUMEN

[This corrects the article DOI: 10.1093/aobpla/ply020.][This corrects the article DOI: 10.1093/aobpla/ply020.].

11.
AoB Plants ; 10(2): 020, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29623183

RESUMEN

Population structure and genetic diversity of invasions are the result of evolutionary processes such as natural selection, drift and founding events. Some invasions are also molded by specific human activities such as selection for cultivars and intentional introduction of desired phenotypes, which can lead to low genetic diversity in the resulting invasion. We investigated the population structure, diversity and origins of a species with both accidental and intentional introduction histories, as well as long-term selection as a cultivar. Dyer's woad (Isatis tinctoria; Brassicaceae) has been used as a dye source for at least eight centuries in Eurasia, was introduced to eastern USA in the 1600s, and is now considered invasive in the western USA. Our analyses of amplified fragment length polymorphisms (AFLPs) from 645 plants from the USA and Eurasia did not find significantly lower gene diversity (Hj) in the invaded compared to the native range. This suggests that even though the species was under cultivation for many centuries, human selection of plants may not have had a strong influence on diversity in the invasion. We did find significantly lower genetic differentiation (Fst) in the invasive range but our results still suggested that there are two distinct invasions in the western USA. Our data suggest that these invasions most likely originated from Switzerland, Ukraine and Germany, which correlates with initial biological control agent survey findings. Genetic information on population structure, diversity and origins assists in efforts to control invasive species, and continued combination of ecological and molecular analyses will help bring us closer to sustainable management of plant invasions.

12.
JCI Insight ; 3(14)2018 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-30046011

RESUMEN

BACKGROUND: The red cell distribution width (RDW) is associated with health outcomes. Whether non-RDW risk information is contained in RBC sizes is unknown. This study evaluated the association of the percentage of extreme macrocytic RBCs (%Macro, RBC volume > 120 fl) and microcytic RBCs (%Micro, RBC volume < 60 fl) and the RDW-size distribution (RDW-sd) with mortality and morbidity. METHODS: Patients (females, n = 165,770; males, n = 100,210) at Intermountain Healthcare were studied if they had a hematology panel between May 2014 and September 2016. Adjusted sex-specific associations of %Macro/%Micro and RDW-sd with mortality and 33 morbidities were evaluated. RESULTS: Among females with fourth-quartile values of %Macro quartile and %Micro (referred to throughout as 4/4), there was an average of 7.2 morbidities versus 2.9 in the lowest risk (LR1) categories, 1/1, 1/2, 2/1, and 2/2 (P < 0.001). Among males, those in the 4/4 category had 8.0 morbidities, while those in the LR1 had 3.4 (P < 0.001). Cox regressions found %Macro/%Micro (4/4 vs. LR1, females: hazard ratio [HR] = 1.97 [95% CI = 1.53, 2.54]; males: HR = 2.17 [CI = 1.72, 2.73]), RDW-sd (quartile 4 vs. 1, females: HR = 1.33 [CI = 1.04, 1.69]; males: HR = 1.41 [CI = 1.10, 1.80]), and RDW (quartile 4 vs. 1, females: HR = 1.59 [CI = 1.26, 2.00]; males: HR = 1.23 [CI = 0.99, 1.52]) independently predicted mortality. Limitations include that the observational design did not reveal causality and unknown confounders may be unmeasured. CONCLUSIONS: Concomitantly elevated %Macro and %Micro predicted the highest mortality risk and the greatest number of morbidities, revealing predictive ability of RBC volume beyond what is measured clinically. Mechanistic investigations are needed to explain the biological basis of these observations. FUNDING: This study was supported by internal Intermountain Heart Institute funds and in-kind support from Sysmex America Inc.


Asunto(s)
Índices de Eritrocitos/fisiología , Volumen de Eritrocitos/fisiología , Eritrocitos/fisiología , Recuento de Células Sanguíneas , Causas de Muerte , Femenino , Humanos , Idaho , Estimación de Kaplan-Meier , Masculino , Morbilidad , Mortalidad , Factores de Riesgo , Distribución por Sexo , Factores Sexuales , Utah
13.
Evolution ; 61(8): 1925-37, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17683434

RESUMEN

For sexual selection to be important in plants, it must occur at pollen load sizes typical of field populations. However, studies of the impact of pollen load size on pollen competition have given mixed results, perhaps because so few of these studies directly examined the outcome of mating when pollen load size was varied. We asked whether seed paternity after mixed pollination of wild radish was affected by pollen load sizes ranging from 22 to 220 pollen grains per stigma. We examined the seed siring abilities of 12 pollen donors across 11 maternal plants. Seed paternity was statistically indistinguishable across the pollen load sizes even though, overall, the pollen donors sired different numbers of seeds. This lack of effect of pollen load size on seed paternity may have occurred because fruit abortion and early abortion or failure of fertilization of seeds increased as load size decreased. Thus, failures of fruits and seeds sired by poorer pollen donors may keep seed paternity constant across pollen load sizes.


Asunto(s)
Polen/fisiología , Raphanus/fisiología , Semillas/fisiología , Reproducción/fisiología
14.
Inflamm Bowel Dis ; 13(2): 219-24, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17206685

RESUMEN

BACKGROUND: Intestinal inflammation associated with inflammatory bowel disease (IBD) is typically characterized by an inflammatory cell infiltrate and pro-inflammatory cytokine production. Of particular interest, the frequency of colony stimulating factor-1 (CSF-l)-expressing cells is increased in active lesions. In this study, we have investigated the role of CSF-1 in mucosal inflammation, using a murine model of colitis induced by dextran sulfate sodium (DSS). METHODS: A neutralizing anti-CSF-1 antibody was administered to Balb/c mice that received DSS in their drinking water. Signs of colitis, such as clinical disease score, cellular infiltrate, and cytokine production, were assessed. RESULTS: Administration of a neutralizing anti-CSF-1 antibody significantly inhibited DSS-induced colitis. Clinical symptoms, such as weight loss and the appearance of diarrhea or fecal blood, were reduced by CSF-1 blockade; histologic scores were also improved. The cellular infiltrate of macrophages and T cells was inhibited and a trend toward reduced production of pro-inflammatory cytokines was noted. CONCLUSIONS: This is the first study to demonstrate that CSF-1 plays an important role in mediating intestinal mucosal inflammation and therefore may prove to be an attractive therapeutic target for intestinal diseases such as inflammatory bowel disease.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Colitis/patología , Factor Estimulante de Colonias de Macrófagos/fisiología , Animales , Movimiento Celular , Colitis/inducido químicamente , Colitis/metabolismo , Colon/metabolismo , Colon/patología , Citocinas/metabolismo , Sulfato de Dextran , Técnicas In Vitro , Factor Estimulante de Colonias de Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C
15.
MAbs ; 8(7): 1319-1335, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27532598

RESUMEN

An antibody format, termed Fab-dsFv, has been designed for clinical indications that require monovalent target binding in the absence of direct Fc receptor (FcR) binding while retaining substantial serum presence. The variable fragment (Fv) domain of a humanized albumin-binding antibody was fused to the C-termini of Fab constant domains, such that the VL and VH domains were individually connected to the Cκ and CH1 domains by peptide linkers, respectively. The anti-albumin Fv was selected for properties thought to be desirable to ensure a durable serum half-life mediated via FcRn. The Fv domain was further stabilized by an inter-domain disulfide bond. The bispecific format was shown to be thermodynamically and biophysically stable, and retained good affinity and efficacy to both antigens simultaneously. In in vivo studies, the serum half-life of Fab-dsFv, 2.6 d in mice and 7.9 d in cynomolgus monkeys, was equivalent to Fab'-PEG.


Asunto(s)
Anticuerpos Biespecíficos/sangre , Fragmentos Fab de Inmunoglobulinas , Región Variable de Inmunoglobulina , Albúmina Sérica/metabolismo , Animales , Anticuerpos Biespecíficos/química , Anticuerpos Biespecíficos/inmunología , Semivida , Humanos , Fragmentos Fab de Inmunoglobulinas/sangre , Fragmentos Fab de Inmunoglobulinas/química , Región Variable de Inmunoglobulina/sangre , Región Variable de Inmunoglobulina/química , Ratones , Albúmina Sérica/inmunología
16.
Immunobiology ; 210(2-4): 109-19, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16164017

RESUMEN

Colony-stimulating factor-1 (CSF-1) regulates the survival, proliferation and differentiation of macrophages. CSF-1-deficient mice are osteopetrotic due to a lack of osteoclasts, while their tissue macrophage deficiencies and an absence of CSF-1 regulation of CSF-1 receptor-expressing cells in the female reproductive tract contribute to their pleiotropic phenotype. To further understand CSF-1 regulation of macrophages in vivo, we developed a neutralizing anti-mouse CSF-1 antibody which was expressed as a recombinant Fab' fragment and coupled to 40 kDa polyethylene glycol. As developmental regulation by CSF-1 is highest during the early post-natal period, the ability of this anti-CSF-1 reagent to inhibit development was tested by regular subcutaneous injection of mice from post-natal days 0.5-57.5. Antibody treatment decreased growth rate, decreased osteoclast number, induced osteopetrosis, decreased macrophage density in bone marrow, liver, dermis, synovium and kidney and decreased adipocyte size in adipose tissue, thereby inducing phenotypes shared by CSF-1- and CSF-1 receptor-deficient mice. While the antibody blocked macrophage development in some tissues, macrophage densities in other tissues were initially high and were reduced by treatment, proving that the antibody also blocked macrophage maintenance. Since cell surface CSF-1 is sufficient for the maintenance of normal synovial macrophage densities, these studies suggest that anti-CSF-1 Fab'-PEG efficiently neutralizes all three CSF-1 isoforms in vivo, namely the secreted proteoglycan, secreted glycoprotein and cell surface glycoprotein. Since CSF-1 has been shown to enhance chronic disease development in a number of mouse model systems, these studies demonstrate the feasibility of neutralizing CSF-1 effects in these models with an anti-CSF-1 antibody.


Asunto(s)
Sistema Inmunológico/crecimiento & desarrollo , Fragmentos Fab de Inmunoglobulinas/farmacología , Factor Estimulante de Colonias de Macrófagos/antagonistas & inhibidores , Factor Estimulante de Colonias de Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Adipocitos/patología , Animales , Huesos/efectos de los fármacos , Huesos/patología , Sistema Inmunológico/efectos de los fármacos , Fragmentos Fab de Inmunoglobulinas/inmunología , Factor Estimulante de Colonias de Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Osteopetrosis/etiología , Osteopetrosis/patología
17.
J Child Neurol ; 20(10): 829-31, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16417880

RESUMEN

In lieu of traditional training of examiners to identify cerebral palsy on a neurologic examination at age 1 year, we proposed an alternative approach using a multimedia training video and CD-ROM we developed after a two-step validation process. We hypothesized that use of CD-ROM interactive training will lead to reliable and valid performance of the neurologic examination by both pediatric neurologists and nonpediatric neurologists. All examiners were asked to take one of six interobserver variability tests found on the CD-ROM on two occasions. In the first interobserver variability evaluation, 89% (531 of 594) of the responses agreed with the gold standard responses. Following annotated feedback to the examiners about the two items that had a 60% correct rate, the correct response rate rose to 93% (114 of 123). In the second interobserver variability evaluation, 88% (493 of 560) of the responses agreed with the gold standard responses. Following annotated feedback to the examiners about the four items that had a 70% correct rate, the correct response rate rose to 96% (104 of 108). Interactive CD-ROM examination training is an efficient and cost-effective means of training both neurologists and non-neurologists to perform structured neurologic examinations in 1-year-old children. It provides an effective means to evaluate interobserver variability, offers a route for feedback, and creates an opportunity to reevaluate variability, both immediately and at periodic intervals.


Asunto(s)
CD-ROM , Parálisis Cerebral/patología , Grabación en Video , Recolección de Datos , Educación , Estudios Epidemiológicos , Humanos , Lactante , Examen Neurológico/normas , Variaciones Dependientes del Observador , Competencia Profesional
18.
J Leukoc Biol ; 73(1): 65-73, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12525563

RESUMEN

The study investigated the role of P-selectin in the responses of eosinophil transmigration and eotaxin generation in vivo elicited by interleukin (IL)-13, as compared with IL-4. Two murine models of leukocyte transmigration were used, migration into cytokine-stimulated peritoneal cavities and through stimulated cremasteric venules, as observed by intravital microscopy. In mice lacking P-selectin, eosinophil infiltration elicited by the cytokines in the peritonitis model was totally inhibited. In the cremaster muscle, however, although spontaneous leukocyte-rolling flux and stimulated leukocyte firm adhesion were inhibited by approximately 97% and approximately 48%, respectively, stimulated transmigration was unaffected. However, IL-13-induced leukocyte transmigration was totally blocked in P-selectin-deficient mice treated with an anti-alpha(4) integrin monoclonal antibody (mAb; PS/2). In comparison, treatment of wild-type mice with the anti-alpha(4) integrin mAb resulted in only partial suppression of IL-13-induced leukocyte transmigration. Significant levels of eotaxin were detected in response to IL-13/IL-4 in both tissues in P-selectin-deficient animals. In conclusion, the regulatory role of P-selectin in leukocyte transmigration elicited by IL-13 appears to be tissue-specific, a phenomenon that is independent of the ability of the cytokine to stimulate eotaxin generation.


Asunto(s)
Quimiocinas CC/biosíntesis , Quimiotaxis de Leucocito , Eosinófilos/citología , Interleucina-13/fisiología , Selectina-P/fisiología , Animales , Quimiocina CCL11 , Integrina alfa4/fisiología , Interleucina-4/fisiología , Rodamiento de Leucocito , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía por Video , Músculo Esquelético/irrigación sanguínea , Selectina-P/genética , Cavidad Peritoneal/citología , Vénulas/citología
19.
Conserv Biol ; 14(6): 1744-1754, 2000 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-35701936

RESUMEN

Changes in historical disturbance regimes have been shown to facilitate non-native plant invasions, but reinstatement of disturbance can be successful only if native colonizers are able to outcompete colonizing invasives. Reintroduction of flooding in the southwestern United States is being promoted as a means of reestablishing Populus deltoides subsp. wislizenii, but flooding can also promote establishment of an introduced, invasive species, Tamarix ramosissima. We investigated competition between Populus and Tamarix at the seedling stage to aid in characterizing the process by which Tamarix may invade and to determine the potential ability of Populus to establish itself with competitive pressure from Tamarix. We planted seedlings of Tamarix and Populus in five ratios at three densities for a total of 15 treatments. The growth response of each species was measured in terms of height, above-ground biomass, and tissue concentrations of nitrogen and phosphorous. These measurements across treatments were modeled as three-dimensional response surfaces. For both species, Populus density was more important than Tamarix density for determining growth response. Both species were negatively affected by increasing numbers of Populus seedlings. Due to the larger size of the native Populus, we predict that its superior competitive ability can lead to its dominance when conditions allow native establishment. Our results suggest that even in the presence of an invader that positively responds to disturbance, reestablishment of historical flooding regimes and post-flood hydrology can restore this ecosystem by promoting its dominant plant species.


RESUMEN: Los cambios en los regímenes históricos de perturbaciones han mostrado que facilitan invasiones de plantas no nativas; sin embargo, la reinstauración de la perturbación solo puede ser exitosa si los colonizadores nativos son capaces de competir y desplazar a las especies invasoras. La reintroducción de las inundaciones en el sudoeste de los Estados Unidos está siendo promovida como una forma de restablecer Populus deltoides subespecie wislizenii, pero las inundaciones pueden promover también el establecimiento de una especie invasora, Tamarix ramosissima. Investigamos la competencia entre Populus y Tamarix al estado de plántula para ayudar a caracterizar el proceso por el cual Tamarix puede invadir y para determinar la habilidad potencial de Populus para establecer presión competitiva contra Tamarix. Sembramos plántulas de Tamarix y Populus en 5 diferentes radios y densidades para un total de 15 tratamientos. La respuesta en crecimiento de cada especie fue medida en forma de altura, biomasa sobre el suelo y concentraciones de nitrógeno y fósforo en tejido. Estas mediciones en los tratamientos fueron modeladas en superficies de respuesta tridimensionales. La densidad de Populus fue más importante para la determinación del crecimiento que la densidad de Tamarix. Ambas especies estuvieron negativamente afectadas por el incremento en el número de plántulas de Populus. Debido al mayor tamaño de la nativa Populus, nosotros predecimos que su superior habilidad competitiva puede conducir a su dominación cuando las condiciones permiten el establecimiento nativo. Nuestros resultados sugieren que aún en presencia de una especie invasora que responde positivamente a las perturbaciones, el restablecimiento de los regímenes históricos de inundaciones y de la hidrología post-inundación puede restaurar este ecosistema al promover a sus especies de plantas dominantes.

20.
MAbs ; 6(3): 774-82, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24670876
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