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1.
Nat Immunol ; 24(8): 1265-1280, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37414907

RESUMEN

High-dimensional approaches have revealed heterogeneity amongst dendritic cells (DCs), including a population of transitional DCs (tDCs) in mice and humans. However, the origin and relationship of tDCs to other DC subsets has been unclear. Here we show that tDCs are distinct from other well-characterized DCs and conventional DC precursors (pre-cDCs). We demonstrate that tDCs originate from bone marrow progenitors shared with plasmacytoid DCs (pDCs). In the periphery, tDCs contribute to the pool of ESAM+ type 2 DCs (DC2s), and these DC2s have pDC-related developmental features. Different from pre-cDCs, tDCs have less turnover, capture antigen, respond to stimuli and activate antigen-specific naïve T cells, all characteristics of differentiated DCs. Different from pDCs, viral sensing by tDCs results in IL-1ß secretion and fatal immune pathology in a murine coronavirus model. Our findings suggest that tDCs are a distinct pDC-related subset with a DC2 differentiation potential and unique proinflammatory function during viral infections.


Asunto(s)
Médula Ósea , Células Dendríticas , Animales , Ratones , Antivirales , Médula Ósea/inmunología , Diferenciación Celular , Células Dendríticas/clasificación , Células Dendríticas/inmunología
2.
Immunity ; 52(6): 1022-1038.e7, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32454024

RESUMEN

Class-switched antibodies to double-stranded DNA (dsDNA) are prevalent and pathogenic in systemic lupus erythematosus (SLE), yet mechanisms of their development remain poorly understood. Humans and mice lacking secreted DNase DNASE1L3 develop rapid anti-dsDNA antibody responses and SLE-like disease. We report that anti-DNA responses in Dnase1l3-/- mice require CD40L-mediated T cell help, but proceed independently of germinal center formation via short-lived antibody-forming cells (AFCs) localized to extrafollicular regions. Type I interferon (IFN-I) signaling and IFN-I-producing plasmacytoid dendritic cells (pDCs) facilitate the differentiation of DNA-reactive AFCs in vivo and in vitro and are required for downstream manifestations of autoimmunity. Moreover, the endosomal DNA sensor TLR9 promotes anti-dsDNA responses and SLE-like disease in Dnase1l3-/- mice redundantly with another nucleic acid-sensing receptor, TLR7. These results establish extrafollicular B cell differentiation into short-lived AFCs as a key mechanism of anti-DNA autoreactivity and reveal a major contribution of pDCs, endosomal Toll-like receptors (TLRs), and IFN-I to this pathway.


Asunto(s)
Linfocitos B/inmunología , Linfocitos B/metabolismo , Comunicación Celular , ADN/inmunología , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Interferón Tipo I/metabolismo , Animales , Anticuerpos Antinucleares/inmunología , Autoantígenos/inmunología , Autoinmunidad , Biomarcadores , Ligando de CD40/deficiencia , Comunicación Celular/genética , Comunicación Celular/inmunología , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Endodesoxirribonucleasas/deficiencia , Técnica del Anticuerpo Fluorescente , Centro Germinal/inmunología , Centro Germinal/metabolismo , Centro Germinal/patología , Lupus Eritematoso Sistémico/etiología , Lupus Eritematoso Sistémico/metabolismo , Ratones , Ratones Noqueados , Receptor Toll-Like 7/metabolismo , Receptor Toll-Like 9/metabolismo
3.
Artículo en Inglés | MEDLINE | ID: mdl-37928883

RESUMEN

Glutamate (Glu) is an excitatory neurotransmitter that plays a critical role in memory. Brain mapping activities of such pathways relied heavily on the ability to release Glu with spatiotemporal precision. Several photo-protecting groups (PPGs), referred to as photocages or cages, were designed to accomplish the release of Glu upon irradiation. Previously reported Glu cages responded to UV upon irradiation with single photons, which limited their use in vivo experiments due to cytotoxicity. Other caged designs suffered from lower quantum efficiency (QE) of release necessitating higher concentrations and/or longer photoirradiation times. There have been limited examples of cages that respond to visible light with single photon irradiation. Herein, we report the efficient preparation of 11 caged Glu examples that respond to two visible wavelengths, 467 nm (thiocoumarin based) and 515-540 nm (BODIPY based). The kinetics of photouncaging were studied for all caged designs, and we report all quantum efficiencies, i.e., quantum yields (Φ), that ranged from 0.0001-0.65. Two of the BODIPY cages are reported here for the first time, and one, Me-BODIPY-Br-Glu, shows the most efficient Glu release with a QE of 0.65. Similar caged designs can be extended to the inhibitory neurotransmitter, GABA. This would enable the use of two visible wavelengths to modulate the release of excitatory and inhibitory neurotransmitters upon demand via optical control.

4.
Molecules ; 24(17)2019 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-31484385

RESUMEN

In this work, two new flavonoids, oblongifolioside A (1) and oblongifolioside B (2), along with eight known compounds (3-10), are isolated from the leaves of Baccharis oblongifolia (Asteraceae). The new structures are established through spectroscopic data and the known compounds are identified by comparison with data reported in the literature. The compounds (1-10) are evaluated in relation to their antiradical properties. Compounds 1 and 2 are found to exhibit high antiradical activity compared to their respective non-acylated flavonoids.


Asunto(s)
Asteraceae/química , Baccharis/química , Flavonoides/química , Extractos Vegetales/química , Hojas de la Planta/química , Ácido Clorogénico/química
5.
Ann Surg Oncol ; 24(9): 2556-2562, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28560596

RESUMEN

BACKGROUND: The benefit of neoadjuvant chemotherapy (NAC) in patients with estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) breast cancers and in invasive lobular carcinoma (ILC) is uncertain due to the low rates of pathologic complete response (pCR). OBJECTIVE: The aim of this study was to determine if pathologic features can identify subsets likely to benefit from NAC. METHODS: Patients with stage I-III ER+, HER2- breast cancer receiving NAC were retrospectively reviewed. Endpoints were downstaging to breast-conserving surgery (BCS) and nodal pCR after NAC. Patients were grouped by progesterone receptor (PR) status and grade/differentiation (high grade or poor [HP] vs. non-HP). RESULTS: From 2007 to 2016, 402 ER+/HER2- cancers in patients receiving NAC were identified. Median age was 50 years, 98% were clinical stage II-III, and 75% were cN+. Overall pCR rate was 5%; breast pCR in 7% and nodal pCR in 15% of cN+ patients (p < 0.0001). Patients with ILC initially ineligible for BCS (n = 56) were less likely to downstage than those with invasive ductal carcinoma (IDC; n = 183, 16 vs. 48%, p ≤ 0.0001), with a similar trend in the axilla (p = 0.086). The rates of BCS eligibility after NAC were highest in PR-/HP patients (62%) and lowest in PR+/non-HP patients (29%) [p = 0.005]. In the axilla, nodal pCR among cN+ patients (n = 301) ranged from 0 to 35% (p < 0.0001) within these groups, and was most frequent in PR-/HP patients. CONCLUSIONS: ER+/HER2- patients most likely to benefit from NAC are those with PR- and HP tumors. Patients with ILC are unlikely to downstage in the breast or axilla compared with IDC. The use of these criteria can assist in defining the initial treatment approach.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/tratamiento farmacológico , Carcinoma Lobular/tratamiento farmacológico , Adulto , Anciano , Axila , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/secundario , Carcinoma Ductal de Mama/cirugía , Carcinoma Lobular/metabolismo , Carcinoma Lobular/secundario , Carcinoma Lobular/cirugía , Quimioterapia Adyuvante , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática , Mastectomía Segmentaria , Persona de Mediana Edad , Terapia Neoadyuvante , Clasificación del Tumor , Estadificación de Neoplasias , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Estudios Retrospectivos
6.
Opt Express ; 25(4): 4403-4413, 2017 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-28241643

RESUMEN

We introduce a birefringent interferometer for Fourier transform (FT) spectroscopy in the mid-infrared, covering the vibrational fingerprint region (5-10 µm, 1000-2000 cm-1), which is crucial for molecular identification. Our interferometer employs the crystal calomel (Hg2Cl2), which combines high birefringence (ne-no≈0.55) with a broad transparency range (0.38-20 µm). We adopt a design based on birefringent wedges, which is simple and compact and guarantees excellent delay accuracy and long-term stability. We demonstrate FTIR spectroscopy, with a frequency resolution of 3 cm-1, as well as two-dimensional IR (2DIR) spectroscopy. Our setup can be extended to other spectroscopic modalities such as vibrational circular dichroism and step-scan FT spectroscopy.

7.
Opt Lett ; 42(4): 663-666, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-28198834

RESUMEN

We report on the generation of narrowband carrier-envelope phase stable mid-infrared (MIR) pulses between 10 and 15 µm. High pulse energies and narrow bandwidths are required for the selective nonlinear excitation of collective modes of matter that is not possible with current sources. We demonstrate bandwidths of <2% at 12.5 µm wavelength through difference frequency generation between two near-infrared (NIR) pulses, which are linearly chirped. We obtain a reduction in bandwidth by one order of magnitude, compared to schemes that make use of transform-limited NIR pulses. The wavelength of the narrowband MIR pulse can be tuned by changing the optical delay between the two chirped NIR pulses.

8.
Plants (Basel) ; 12(6)2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36986952

RESUMEN

Baccharis is one of the largest genera of Asteraceae and its species are used in folk medicine for several medicinal purposes due to the presence of bioactive compounds. We investigated the phytochemical composition of polar extracts of B. sphenophylla. Using chromatographic procedures, diterpenoids (ent-kaurenoic acid), flavonoids (hispidulin, eupafolin, isoquercitrin, quercitrin, biorobin, rutin, and vicenin-2), caffeic acid, and chlorogenic acid derivatives (5-O-caffeoylquinic acid and its methyl ester, 3,4-di-O-caffeoylquinic acid, 4,5-di-O-caffeoylquinic acid, and 3,5-di-O-caffeoylquinic acid and its methyl ester) were isolated from polar fractions and are described. The extract, polar fractions, and fifteen isolated compounds were evaluated in relation to radical scavenging activity using two assays. Chlorogenic acid derivatives and flavonols exhibited higher antioxidant effects, confirming that B. sphenophylla is an important source of phenolic compounds with antiradical properties.

9.
Otolaryngol Head Neck Surg ; 169(1): 12-20, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36939486

RESUMEN

OBJECTIVE: Previous studies have suggested that patients with aspirin-exacerbated respiratory disease (AERD) have a high likelihood of alcohol intolerance. The purpose of this systematic review is to identify if there is sufficient evidence to confirm this correlation and the impact of medical therapy on subsequent alcohol tolerance. DATA SOURCES: PubMed, EMBASE, SCOPUS, EBSCO, Google Scholar, Cochrane Library, and Grey literature. We also performed snowballing on the identified observational studies (OS) for additional data. REVIEW METHODS: A systematic review was conducted from 1968 to 2022 to identify those studies describing AERD symptomatology triggered by alcohol intake. The primary outcome was to analyze the current literature for the association between alcohol intolerance and AERD symptoms. The secondary outcome looked for improvement in alcohol tolerance after aspirin desensitization or biological therapy. RESULTS: A total of 775 studies were identified and 40 abstracts were evaluated. From these, 5 studies met the inclusion criteria. Of the 5 manuscripts, there was 1 case-control, 2 cohort, and 2 cross-sectional studies. A total of 522 participants with AERD and a history of alcohol consumption were included, with 52.8% reporting at least 1 sinopulmonary exacerbation after alcohol intake. One of 3 studies noted improvement in alcohol tolerance after medical therapy with aspirin desensitization. CONCLUSION: The current literature suggests that patients with AERD have a high risk of alcohol intolerance. Additionally, aspirin desensitization may improve alcohol tolerance in this patient population.


Asunto(s)
Asma Inducida por Aspirina , Pólipos Nasales , Sinusitis , Humanos , Aspirina/efectos adversos , Estudios Transversales , Asma Inducida por Aspirina/terapia , Sinusitis/cirugía , Desensibilización Inmunológica , Pólipos Nasales/complicaciones
10.
Exp Parasitol ; 130(2): 141-5, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22143090

RESUMEN

Leishmaniasis and Chagas' are parasitic protozoan diseases that affect the poorest population in the world, causing a high mortality and morbidity. As a result of highly toxic and long-term treatments, novel, safe and more efficacious drugs are essential. In this work, the CH(2)Cl(2) phase from MeOH extract from the leaves of Baccharis retusa DC. (Asteraceae) was fractioned to afford two flavonoids: naringenin (1) and sakuranetin (2). These compounds were in vitro tested against Leishmania spp. promastigotes and amastigotes and Trypanosoma cruzi trypomastigotes and amastigotes. Compound 2 presented activity against Leishmania (L.) amazonensis, Leishmania (V.) braziliensis, Leishmania (L.) major, and Leishmania (L.) chagasi with IC(50) values in the range between 43 and 52 µg/mL and against T. cruzi trypomastigotes (IC(50)=20.17 µg/mL). Despite of the chemical similarity, compound 1 did not show antiparasitic activity. Additionally, compound 2 was subjected to a methylation procedure to give sakuranetin-4'-methyl ether (3), which resulted in an inactive compound against both Leishmania spp. and T. cruzi. The obtained results indicated that the presence of one hydroxyl group at C-4' associated to one methoxyl group at C-7 is important to the antiparasitic activity. Further drug design studies aiming derivatives could be a promising tool for the development of new therapeutic agents for Leishmaniasis and Chagas' disease.


Asunto(s)
Antiprotozoarios/farmacología , Baccharis/química , Flavanonas/farmacología , Leishmania/efectos de los fármacos , Extractos Vegetales/farmacología , Trypanosoma/efectos de los fármacos , Animales , Antiprotozoarios/química , Antiprotozoarios/aislamiento & purificación , Bioensayo , Cricetinae , Flavanonas/química , Flavanonas/aislamiento & purificación , Flavonoides/química , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Concentración 50 Inhibidora , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/parasitología , Mesocricetus , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Relación Estructura-Actividad
11.
Parasitol Res ; 110(1): 95-101, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21614544

RESUMEN

Leishmaniasis, Chagas disease, and malaria affect the poorest population around the world, with an elevated mortality and morbidity. In addition, the therapeutic alternatives are usually toxic or ineffective drugs especially those against the trypanosomatids. In the course of selection of new anti-protozoal compounds from Brazilian flora, the CH(2)C(l2) phase from MeOH extract obtained from the leaves of Pentacalia desiderabilis (Vell.) Cuatrec. (Asteraceae) showed in vitro anti-leishmanial, anti-malarial, and anti-trypanosomal activities. The chromatographic fractionation of the CH(2)Cl(2) phase led to the isolation of the bioactive compound, which was characterized as jacaranone [methyl (1-hydroxy-4-oxo-2,5-cyclohexandienyl)acetate], by spectroscopic methods. This compound showed activity against promastigotes of Leishmania (L.) chagasi, Leishmania (V.) braziliensis, and Leishmania (L.). amazonensis showing an IC(50) of 17.22, 12.93, and 11.86 µg/mL, respectively. Jacaranone was also tested in vitro against the Trypanosoma cruzi trypomastigotes and Plasmodium falciparum chloroquine-resistant parasites (K1 strain) showing an IC(50) of 13 and 7.82 µg/mL, respectively, and was 3.5-fold more effective than benznidazole in anti-Trypanosoma cruzi assay. However, despite of the potential against promatigotes forms, this compound was not effective against amastigotes of L. (L.) chagasi and T. cruzi. The cytotoxicity study using Kidney Rhesus monkey cells, demonstrated that jacaranone showed selectivity against P. falciparum (21.75 µg/mL) and a selectivity index of 3. The obtained results suggested that jacaranone, as other similar secondary metabolites or synthetic analogs, might be useful tolls for drug design for in vivo studies against protozoan diseases.


Asunto(s)
Antiprotozoarios/farmacología , Asteraceae/química , Benzoquinonas/farmacología , Leishmania/efectos de los fármacos , Plasmodium falciparum/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos , Animales , Antiprotozoarios/aislamiento & purificación , Antiprotozoarios/toxicidad , Benzoquinonas/aislamiento & purificación , Benzoquinonas/toxicidad , Brasil , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cromatografía , Concentración 50 Inhibidora , Macaca mulatta , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Extractos Vegetales/toxicidad , Hojas de la Planta/química , Análisis Espectral
12.
Parasitol Res ; 109(1): 231-6, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21243506

RESUMEN

Parasitic protozoan diseases affect the poorest population in developing countries. Leishmaniasis and Chagas disease have been included among the most important threats for public health in Central and South American continent, with few therapeutic alternatives and highly toxic drugs. In the course of selection of novel drug candidates, we studied the anti-protozoal potential of Drimys brasiliensis. Thus, the crude hexane extract from stem bark as well as its main derivative, the sesquiterpene polygodial, were tested using in vitro assays. The crude hexane extract and polygodial showed activity against Leishmania spp. in the range between 22 and 62 µg/mL, but polygodial demonstrated high parasite selectivity towards Trypanosoma cruzi trypomastigotes (2 µg/mL), with a selectivity index of 19. Finally, polygodial showed a leishmanicidal effect, inducing intense ultrastructural damages in Leishmania in short-time incubation. The obtained results suggested that polygodial could be used as a tool for drug design studies against protozoan diseases and as a candidate molecule for further in vivo studies against T. cruzi.


Asunto(s)
Antiprotozoarios/farmacología , Drimys/química , Leishmania/efectos de los fármacos , Extractos Vegetales/farmacología , Sesquiterpenos/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Antiprotozoarios/aislamiento & purificación , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cricetinae , Concentración 50 Inhibidora , Macaca mulatta , Ratones , Pruebas de Sensibilidad Parasitaria , Corteza de la Planta/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/toxicidad , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/toxicidad
13.
Parasitol Res ; 108(3): 529-36, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20886232

RESUMEN

Species of Baccharis exhibit antibiotic, antiseptic, wound-healing, and anti-protozoal properties, and have been used in the traditional medicine of South America for the treatment of several diseases. In the present work, the fractionation of EtOH extract from aerial parts of Baccharis uncinella indicated that the isolated compounds caffeic acid and pectolinaringenin showed inhibitory activity against Leishmania (L.) amazonensis and Leishmania (V.) braziliensis promastigotes, respectively. Moreover, amastigote forms of both species were highly sensible to the fraction composed by oleanolic + ursolic acids and pectolinaringenin. Caffeic acid also inhibited amastigote forms of L. (L.) amazonensis, but this effect was weak in L. (V.) braziliensis amastigotes. The treatment of infected macrophages with these compounds did not alter the levels of nitrates, indicating a direct effect of the compounds on amastigote stages. The results presented herein suggest that the active components from B. uncinella can be important to the design of new drugs against American tegumentar leishmaniases.


Asunto(s)
Baccharis/química , Leishmania braziliensis/efectos de los fármacos , Leishmania mexicana/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Animales , Ácidos Cafeicos/farmacología , Línea Celular , Cromonas/farmacología , Leishmania braziliensis/crecimiento & desarrollo , Leishmania mexicana/crecimiento & desarrollo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/parasitología , Espectroscopía de Resonancia Magnética , Medicina Tradicional , Ratones , Nitratos/metabolismo , Óxido Nítrico/metabolismo , Ácido Oleanólico/farmacología , Pruebas de Sensibilidad Parasitaria , Plantas Medicinales/química , Triterpenos/farmacología , Ácido Ursólico
14.
Pharm Biol ; 49(6): 602-7, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21554002

RESUMEN

CONTEXT: Species of Baccharis exhibit antibiotic, antiseptic, and wound-healing properties, and have been used in the traditional medicine of South America for the treatment of inflammation, headaches, diabetes, and hepatobiliary disorders. OBJECTIVE: To investigate the anti-inflammatory activity of organic phases from EtOH extract of the aerial parts of Baccharis uncinella DC (Asteraceae). MATERIALS AND METHODS: The crude EtOH extract from the aerial parts of B. uncinella was subjected to partition procedures and the corresponding CH(2)Cl(2) and EtOAc phases were subjected to several chromatographic separation procedures. Thus, these phases and their purified compounds were assayed for evaluation of anti-inflammatory activity. RESULTS: The CH(2)Cl(2) phase from EtOH extract from B. uncinella contained two triterpenoids (oleanolic and ursolic acids) and one flavonoid (pectolinaringenin), whereas the respective EtOAc phase showed to be composed mainly by two phenylpropanoid derivatives (caffeic and ferulic acids). The CH(2)Cl(2) and EtOAc phases as well as their isolated compounds exhibited anti-inflammatory effects against inflammatory reactions induced by phospholipase A2 (from Crotalus durissus terrificus venom) and by carrageenan. DISCUSSION AND CONCLUSION: The results suggested that the components obtained from partition phases of EtOH extract of B. uncinella could represent lead molecules for the development of anti-inflammatory agents. Additionally, the results confirmed the use of Baccharis genus in the traditional medicine of South America for the treatment of inflammation and other heath disorders. To date, the present work describes for the first time the anti-inflammatory effects of compounds isolated from B. uncinella.


Asunto(s)
Antiinflamatorios/uso terapéutico , Baccharis/química , Inflamación/tratamiento farmacológico , Fosfolipasas A2 Secretoras/antagonistas & inhibidores , Fitoterapia/métodos , Extractos Vegetales/uso terapéutico , Acetatos/química , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Evaluación Preclínica de Medicamentos , Etanol/química , Inflamación/inducido químicamente , Masculino , Medicina Tradicional/métodos , Cloruro de Metileno/química , Componentes Aéreos de las Plantas/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Ratas , Ratas Wistar
15.
Sci Immunol ; 6(58)2021 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-33811059

RESUMEN

Plasmacytoid dendritic cells (pDCs) can rapidly produce interferons and other soluble factors in response to extracellular viruses or virus mimics such as CpG-containing DNA. pDCs can also recognize live cells infected with certain RNA viruses, but the relevance and functional consequences of such recognition remain unclear. We studied the response of primary DCs to the prototypical persistent DNA virus, human cytomegalovirus (CMV). Human pDCs produced high amounts of type I interferon (IFN-I) when incubated with live CMV-infected fibroblasts but not with free CMV; the response involved integrin-mediated adhesion, transfer of DNA-containing virions to pDCs, and the recognition of DNA through TLR9. Compared with transient polyfunctional responses to CpG or free influenza virus, pDC response to CMV-infected cells was long-lasting, dominated by the production of IFN-I and IFN-III, and lacked diversification into functionally distinct populations. Similarly, pDC activation by influenza-infected lung epithelial cells was highly efficient, prolonged, and dominated by interferon production. Prolonged pDC activation by CMV-infected cells facilitated the activation of natural killer cells critical for CMV control. Last, patients with CMV viremia harbored phenotypically activated pDCs and increased circulating IFN-I and IFN-III. Thus, recognition of live infected cells is a mechanism of virus detection by pDCs that elicits a unique antiviral immune response.


Asunto(s)
Células Dendríticas/inmunología , Fibroblastos/inmunología , Interferón Tipo I/metabolismo , Interferones/metabolismo , Células Cultivadas , Técnicas de Cocultivo , Islas de CpG/inmunología , Citomegalovirus/inmunología , Células Dendríticas/metabolismo , Fibroblastos/virología , Interacciones Microbiota-Huesped/inmunología , Humanos , Cultivo Primario de Células , Interferón lambda
16.
J Exp Med ; 218(5)2021 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-33783474

RESUMEN

Antibodies to double-stranded DNA (dsDNA) are prevalent in systemic lupus erythematosus (SLE), particularly in patients with lupus nephritis, yet the nature and regulation of antigenic cell-free DNA (cfDNA) are poorly understood. Null mutations in the secreted DNase DNASE1L3 cause human monogenic SLE with anti-dsDNA autoreactivity. We report that >50% of sporadic SLE patients with nephritis manifested reduced DNASE1L3 activity in circulation, which was associated with neutralizing autoantibodies to DNASE1L3. These patients had normal total plasma cfDNA levels but showed accumulation of cfDNA in circulating microparticles. Microparticle-associated cfDNA contained a higher fraction of longer polynucleosomal cfDNA fragments, which bound autoantibodies with higher affinity than mononucleosomal fragments. Autoantibodies to DNASE1L3-sensitive antigens on microparticles were prevalent in SLE nephritis patients and correlated with the accumulation of cfDNA in microparticles and with disease severity. DNASE1L3-sensitive antigens included DNA-associated proteins such as HMGB1. Our results reveal autoantibody-mediated impairment of DNASE1L3 activity as a common nongenetic mechanism facilitating anti-dsDNA autoreactivity in patients with severe sporadic SLE.


Asunto(s)
Anticuerpos Antinucleares/inmunología , Autoanticuerpos/inmunología , ADN/inmunología , Endodesoxirribonucleasas/inmunología , Lupus Eritematoso Sistémico/inmunología , Nefritis Lúpica/inmunología , Adulto , Animales , Anticuerpos Antinucleares/sangre , Autoanticuerpos/sangre , Micropartículas Derivadas de Células/inmunología , Micropartículas Derivadas de Células/metabolismo , Ácidos Nucleicos Libres de Células/sangre , Ácidos Nucleicos Libres de Células/inmunología , Niño , Endodesoxirribonucleasas/sangre , Endodesoxirribonucleasas/genética , Endodesoxirribonucleasas/metabolismo , Femenino , Células HEK293 , Proteína HMGB1/inmunología , Proteína HMGB1/metabolismo , Humanos , Lupus Eritematoso Sistémico/metabolismo , Nefritis Lúpica/metabolismo , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Índice de Severidad de la Enfermedad
17.
Acta Crystallogr Sect F Struct Biol Cryst Commun ; 66(Pt 11): 1487-9, 2010 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-21045302

RESUMEN

Glioma pathogenesis-related protein 1 (GLIPR1) is a member of the CAP superfamily that includes proteins from a wide range of eukaryotic organisms. The biological functions of most CAP proteins, including GLIPR1, are unclear. GLIPR1 is up-regulated in aggressive glioblastomas and contributes to the invasiveness of cultured glioblastoma cells. In contrast, decreased GLIPR1 expression is associated with advanced prostate cancer. Forced GLIPR1 overexpression is pro-apoptotic in prostate cancer cells and is being tested in clinical trials as an experimental prostate-cancer therapy. Human GLIPR1 was expressed as a truncated soluble protein (sGLIPR1), purified and crystallized. Useful X-ray data have been collected to beyond 1.9 Šresolution from a crystal that belonged to the orthorhombic space group P2(1)2(1)2 with average unit-cell parameters a = 85.1, b = 79.5, c = 38.9 Šand either a monomer or dimer in the asymmetric unit.


Asunto(s)
Proteínas de Neoplasias/química , Proteínas del Tejido Nervioso/química , Cristalización , Cristalografía por Rayos X , Expresión Génica , Humanos , Proteínas de la Membrana , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/aislamiento & purificación , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/aislamiento & purificación , Solubilidad
18.
Parasitol Res ; 106(5): 1245-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20165875

RESUMEN

In the course of selection of new bioactive compounds from Brazilian flora, the crude MeOH extract from the leaves of Baccharis retusa DC. (Asteraceae) showed potential against Leishmania sp. and Trypanosoma cruzi. Chromatographic fractionation of the dichloromethane phase from MeOH extract yielded great amounts of the bioactive derivative, which was characterized as 5,6,7-trihydroxy-4'-methoxyflavanone. The structure of this compound was established on the basis of spectroscopic data analysis, mainly nuclear magnetic resonance and mass spectrometry.


Asunto(s)
Antiprotozoarios/farmacología , Baccharis/química , Flavanonas/farmacología , Leishmania/efectos de los fármacos , Extractos Vegetales/farmacología , Hojas de la Planta/química , Trypanosoma cruzi/efectos de los fármacos , Animales , Antiprotozoarios/química , Antiprotozoarios/aislamiento & purificación , Brasil , Células Cultivadas , Fraccionamiento Químico , Cromatografía Liquida , Flavanonas/química , Flavanonas/aislamiento & purificación , Humanos , Concentración 50 Inhibidora , Macaca mulatta , Macrófagos/parasitología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Ratones , Ratones Endogámicos BALB C , Monocitos/parasitología , Extractos Vegetales/aislamiento & purificación
19.
Chem Biodivers ; 7(11): 2771-82, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21072777

RESUMEN

The chemical composition and seasonal variation throughout one year of the essential oils from leaves of Baccharis microdonta and B. elaeagnoides, collected in Campos do Jordão, SP, were investigated. The composition of the latter species has been described for the first time. By GC (RI) and GC/MS analysis, 43 compounds were identified, and a predominance of oxygenated sesquiterpene derivatives was found in both species. The main components of the B. microdonta oils were elemol (31; 11.7-30.6%), spathulenol (34; 4.7-9.1%), ß-caryophyllene (19; 3.7-6.2%), and germacrene D (24; 2.9-12.2%), and those of the B. elaeagnoides oils were 34 (10.1-21.5%), viridiflorol (35; 3.6-18.4%), 24 (0.9-13.8%), and 19 (3.5-9.4%). The identified compounds were grouped according to their respective C-skeletons, and the percentages of occurrence of the C-skeletons in the essential oils of leaves collected in the four seasons allowed identifying the preferential accumulation of different types of C-skeletons as well as the seasonal variation of the biosynthetic routes over the studied period.


Asunto(s)
Baccharis/química , Aceites Volátiles/química , Cromatografía de Gases y Espectrometría de Masas , Aceites Volátiles/metabolismo , Hojas de la Planta/química , Estaciones del Año
20.
Sci Immunol ; 5(45)2020 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-32220976

RESUMEN

Tissue-resident macrophages are a diverse population of cells that perform specialized functions including sustaining tissue homeostasis and tissue surveillance. Here, we report an interstitial subset of CD169+ lung-resident macrophages that are transcriptionally and developmentally distinct from alveolar macrophages (AMs). They are primarily localized around the airways and are found in close proximity to the sympathetic nerves in the bronchovascular bundle. These nerve- and airway-associated macrophages (NAMs) are tissue resident, yolk sac derived, self-renewing, and do not require CCR2+ monocytes for development or maintenance. Unlike AMs, the development of NAMs requires CSF1 but not GM-CSF. Bulk population and single-cell transcriptome analysis indicated that NAMs are distinct from other lung-resident macrophage subsets and highly express immunoregulatory genes under steady-state and inflammatory conditions. NAMs proliferated robustly after influenza infection and activation with the TLR3 ligand poly(I:C), and in their absence, the inflammatory response was augmented, resulting in excessive production of inflammatory cytokines and innate immune cell infiltration. Overall, our study provides insights into a distinct subset of airway-associated pulmonary macrophages that function to maintain immune and tissue homeostasis.


Asunto(s)
Macrófagos Alveolares/inmunología , Neuronas/inmunología , Animales , Homeostasis/inmunología , Factor Estimulante de Colonias de Macrófagos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Saco Vitelino/citología , Saco Vitelino/inmunología
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