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1.
Noncoding RNA ; 10(1)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38392970

RESUMEN

There are many articles on the quantitative analysis of miRNAs contained in a population of EVs of different sizes under various physiological and pathological conditions. For such analysis, it is important to correctly quantify the miRNA contents of EVs. It should be considered that quantification is skewed depending on the isolation protocol, and different miRNAs are degraded by nucleases with different efficiencies. In addition, it is important to consider the contribution of miRNAs coprecipitating with the EVs population, because the amount of miRNAs in the EVs population under study is skewed without appropriate enzymatic treatment. By studying a population of EVs from the blood plasma of healthy donors, we found that the absolute amount of miRNA inside the vesicles is commensurate with the amount of the same type of miRNA adhered to the outside of the EVs. The inside/outside ratio ranged from 1.02 to 2.64 for different investigated miRNAs. According to our results, we propose the hypothesis that high occupancy of miRNAs on the outer surface of EVs influence on the transporting RNA repertoire no less than the inner cargo received from the host cell.

2.
J Environ Radioact ; 272: 107346, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38043218

RESUMEN

It is well known that one of the most important risk factors in underground environment is the harmful effects of radon. The reasons for strong seasonal fluctuations in radon content in underground environments remain not fully understood. The purpose of this article is to improve existing ideas about this phenomenon. The article presents the results of a study of radon transport in two different underground spaces - the Beshtaugorskiy uranium mine (North Caucasus) and the Kungur Ice Cave (Middle Ural). We have used the direct measurements of the equilibrium equivalent concentration (EEC) of radon progeny in air, as well as the air flow velocity. A very wide range and strong seasonal variations in the radon levels have been recorded in both cases. The EEC has a range of 11-6653 by Bq m-3 and 10-89,020 Bq m-3 in the Kungur cave and the Beshtaugorskiy mine, respectively. It has been established that seasonal fluctuations in radon levels both in the mine and in the cave are caused by the same process - convective air circulation in the underground space due to the temperature difference between the mountain massif and the atmosphere (so called chimney effect). Overall, these results indicate that due to convective air circulation, underground spaces are periodically intensively ventilated with atmospheric air, and then, on the contrary, they are filled with radon-enriched air that seeps into caves or adits from rocks and ores. In both cases, the EEC of radon progeny exceeds the permissible level for the population and workers. The results of this study highlight the need for the development of measures to limit the presence of people in the surveyed underground spaces.


Asunto(s)
Contaminantes Radiactivos del Aire , Monitoreo de Radiación , Radón , Uranio , Humanos , Radón/análisis , Contaminantes Radiactivos del Aire/análisis , Estaciones del Año , Hielo , Hijas del Radón , Cuevas
3.
Ann Hum Biol ; 50(1): 399-406, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37815229

RESUMEN

Background: Human identification and kinship testing in forensic science rely on Short Tandem Repeat (STR) multiplex kits, typically containing loci recommended by standard sets. However, complementary kits with additional STR loci can be valuable in complex cases. Allele frequency databases specific to the population are essential for accurate forensic analysis.Aim: This study aimed to generate allele frequencies and population genetic data for 44 autosomal STR loci from SureID® PanGlobal and 27comp kits in English and Irish populations for forensic casework, human identification, and kinship testing.Subjects and methods: Buccal swab samples from 645 White Caucasians (365 English, 280 Irish) were collected. DNA was extracted and amplified using the mentioned kits. Quality control, statistical analysis, and genetic distance calculations were performed.Results: Both kits demonstrated robustness with no significant deviations from Hardy-Weinberg Equilibrium (HWE). Variant alleles and minor discordances between kits were observed. Syntenic STR pairs were identified but showed no significant linkage. A close genetic relationship was found between English and Irish populations, allowing for combined databases.Conclusions: The SureID® PanGlobal and 27comp kits showed high discriminatory power and reliability in the English and Irish populations. Care is needed when handling variant alleles, discordances, and syntenic loci. Combining data from both populations is feasible for a comprehensive database. Further studies are required to explore their effectiveness in diverse populations.


Asunto(s)
ADN , Genética de Población , Humanos , Reproducibilidad de los Resultados , Frecuencia de los Genes , ADN/genética , Repeticiones de Microsatélite/genética , Variación Genética
4.
Sci Total Environ ; 903: 166348, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-37591399

RESUMEN

Several machine learning algorithms including artificial neural networks (ANN), random forest (RF) and multivariate adaptive regression splines (MARS) were used to construct a radon flux density (RFD) map of Moscow for the purpose of finding which one of them would be the best for radon delineation. Predictors used included geological soil classes for quaternary and some pre-quaternary sediment types, elevations of quaternary and pre-quaternary layers, 226Ra content in soil, ambient dose equivalent rate (ADER), distances to geodynamically active zones and lineaments. Training of the models was performed using previously collected radon flux density data from approximately ten thousand of measurements over 756 sites. ANN and RF algorithms produced the best maps with high correlation coefficients and low mean squared error, while MARS failed to get a high correlation coefficient and low mean squared error. Predictions made using RF were found to be more conservative due to higher prediction values of RFD, while those made using ANN were likely more realistic in their prediction value distribution, leading to the conclusion that RF is better for the purposes of delineation, while ANN is better for predicting average RFD values. Based on the constructed maps, the main factors affecting the flow of radon in the city were determined.

5.
J Cell Biol ; 222(6)2023 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-37036444

RESUMEN

Homeostatic maintenance and repair of lymphatic vessels are essential for health. We investigated the dynamics and the molecular mechanisms of lymphatic endothelial cell (LEC) renewal in adult mesenteric quiescent lymphatic vasculature using label-retention, lineage tracing, and cell ablation strategies. Unlike during development, adult LEC turnover and proliferation was confined to the valve regions of collecting vessels, with valve cells displaying the shortest lifespan. Proliferating valve sinus LECs were the main source for maintenance and repair of lymphatic valves. We identified mechanistic target of rapamycin complex 1 (mTORC1) as a mechanoresponsive pathway activated by fluid shear stress in LECs. Depending on the shear stress level, mTORC1 activity drives division of valve cells or dictates their mechanic resilience through increased protein synthesis. Overactivation of lymphatic mTORC1 in vivo promoted supernumerary valve formation. Our work provides insights into the molecular mechanisms of maintenance of healthy lymphatic vascular system.


Asunto(s)
Vasos Linfáticos , Diana Mecanicista del Complejo 1 de la Rapamicina , Células Endoteliales/metabolismo , Homeostasis , Linfangiogénesis/genética , Vasos Linfáticos/metabolismo , Transducción de Señal , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo
6.
Circ Res ; 132(9): 1203-1225, 2023 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-37104555

RESUMEN

Secondary lymphoid organs, such as lymph nodes, harbor highly specialized and compartmentalized niches. These niches are optimized to facilitate the encounter of naive lymphocytes with antigens and antigen-presenting cells, enabling optimal generation of adaptive immune responses. Lymphatic vessels of lymphoid organs are uniquely specialized to perform a staggering variety of tasks. These include antigen presentation, directing the trafficking of immune cells but also modulating immune cell activation and providing factors for their survival. Recent studies have provided insights into the molecular basis of such specialization, opening avenues for better understanding the mechanisms of immune-vascular interactions and their applications. Such knowledge is essential for designing better treatments for human diseases given the central role of the immune system in infection, aging, tissue regeneration and repair. In addition, principles established in studies of lymphoid organ lymphatic vessel functions and organization may be applied to guide our understanding of specialization of vascular beds in other organs.


Asunto(s)
Células Endoteliales , Vasos Linfáticos , Humanos , Ganglios Linfáticos Agregados , Ganglios Linfáticos , Linfocitos , Tejido Linfoide
7.
Polymers (Basel) ; 15(8)2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37112086

RESUMEN

The results of systematic studies on the surface energy γ and its polar γP and dispersion γD components of statistical copolymers of styrene and butadiene, acrylonitrile and butadiene, and butyl acrylate and vinyl acetate, with regard to their thermal prehistory, are generalized. Along with copolymers, the surfaces of their composing homopolymers were examined. We obtained the energy characteristics of the adhesive surfaces of copolymers that contacted with air, high-energy aluminium Al (γ = 160 mJ/m2), and the low-energy substrate surface of polytetrafluoroethylene F4 (PTFE) (γ = 18 mJ/m2). The surfaces of copolymers in contact with air, aluminium, and PTFE were investigated for the first time. It was found that the surface energy of these copolymers tended to occupy an intermediate value between the surface energy of the homopolymers. The additive nature of the change in the surface energy of the copolymers with their composition, as previously established in the works of Wu, extends to the dispersive component of the free surface energy γD and the critical surface energy γcr, according to Zisman. It was shown that a significant influence on the adhesive activity of copolymers was exerted by the substrate surface upon which the adhesive was formed. Thus, for the butadiene-nitrile copolymer (BNC) samples formed in contact with a high-energy substrate, their surface energy growth was associated with a significant increase in the polar component of the surface energy γP from 2 mJ/m2 for the samples formed in contact with air, to an increase from 10 to 11 mJ/m2 for the samples formed in contact with Al. The reason why the interface influenced the change in the energy characteristics of the adhesives was the selective interaction of each macromolecule fragment with the active centres of the substrate surface. As a result, the composition of the boundary layer changed and it became enriched with one of the components. The structure of such layers is nonequilibrium. The thermal annealing of copolymers in the mode of a stepwise temperature increase led to a convergence in the values of γ, asymptotically tending to the value characteristic of the surface of the copolymers formed in air. The activation energies for the processes of the conformational rearrangements of the macromolecules in the surface layers of the copolymers were calculated. It was found that the conformational rearrangements of the macromolecules in the surface layers occurred as a result of the internal rotation of the functional groups that determined the polar component of the surface energy.

8.
EMBO Rep ; 24(3): e55328, 2023 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-36715148

RESUMEN

The vasculature is a key regulator of leukocyte trafficking into the central nervous system (CNS) during inflammatory diseases including multiple sclerosis (MS). However, the impact of endothelial-derived factors on CNS immune responses remains unknown. Bioactive lipids, in particular oxysterols downstream of Cholesterol-25-hydroxylase (Ch25h), promote neuroinflammation but their functions in the CNS are not well-understood. Using floxed-reporter Ch25h knock-in mice, we trace Ch25h expression to CNS endothelial cells (ECs) and myeloid cells and demonstrate that Ch25h ablation specifically from ECs attenuates experimental autoimmune encephalomyelitis (EAE). Mechanistically, inflamed Ch25h-deficient CNS ECs display altered lipid metabolism favoring polymorphonuclear myeloid-derived suppressor cell (PMN-MDSC) expansion, which suppresses encephalitogenic T lymphocyte proliferation. Additionally, endothelial Ch25h-deficiency combined with immature neutrophil mobilization into the blood circulation nearly completely protects mice from EAE. Our findings reveal a central role for CNS endothelial Ch25h in promoting neuroinflammation by inhibiting the expansion of immunosuppressive myeloid cell populations.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Oxiesteroles , Ratones , Animales , Células Endoteliales/metabolismo , Oxiesteroles/metabolismo , Enfermedades Neuroinflamatorias , Sistema Nervioso Central/metabolismo , Ratones Endogámicos C57BL
9.
Polymers (Basel) ; 16(1)2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-38201732

RESUMEN

From the examples of three and four-component polymer-polymer systems characterized by amorphous separation, an original technique for determining the pair parameters of interaction between components based on the sorption isotherms of common solvent vapor, particularly water vapor, has been developed. The possibility of calculating thermodynamic characteristics of multicomponent polymer compositions with specific interactions of functional groups from experimentally obtained sorption isotherms is shown. An algorithm for calculating pair interaction parameters, estimating concentration dependences of chemical potential and Gibbs free energy of mixing, and predicting the phase state of polymer mixtures was presented for the first time for such systems. The technique was tested on the example of systems poly(N-vinylpyrrolidone) (PNVP)-polyethylene glycol (PEG), PNVP-PEG-Poly(acrylic acid) (PAA), poly(N-vinylcaprolactam) (PNVCL)-PEG, and polyvinyl alcohol (PVA)-PEG.

10.
J Eye Mov Res ; 16(3)2023.
Artículo en Inglés | MEDLINE | ID: mdl-38370527

RESUMEN

This study examines the process of reading polycode advertising posters, focusing in particular on the effect of a pun in the headline. The pun, or a sequence of lexical items that can be perceived as ambiguous, is contained in the headline and different meanings of this sequence are supported by the picture and text. The results of the preliminary experiment showed that advertisements with puns are rated as more attractive, original, effective and positive compared to advertisements without puns. We hypothesized that puns in the headlines increase cognitive effort in processing posters, leading to higher evaluations. The main experiment tested this and examined differences in eye movement when reading posters with and without puns. Fifty-five Russian participants viewed advertisements while their eye movements were recorded. Our results showed no fundamental differences in the general pattern of viewing advertisement posters with and without puns. We found that readers start to perceive polycode advertisements from the text and spend more time reading the text than looking at an image. These findings shed light on how attention is distributed between verbal and non-verbal components of polycode texts, and which type of poster is more effective for information retrieval at different processing levels.

11.
Sci Total Environ ; 852: 158382, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36049692

RESUMEN

This article presents the results of a long-term soil radon and meteorological parameter monitoring study in the fault zone at Mt. Beshtau, North Caucasus, which for more than 3 years. Strong seasonal variations in the radon levels with maxima during summer and minima during winter were recorded. The values of radon exhalation and soil radon concentration have a range of 0.025-25 Bq m 2 s -1 and 1-170 kBq m -3, respectively. In addition, measurements of the air radon concentration, and direction of air movement at the adits mouths of the former uranium mine on the same mountain were carried out. Seasonal radon variations, similar to those observed in fault zones, were recorded at the mouths of adits. It was established that radon anomalies are associated with the periodic release of mine air from the fractures and tunnels into the atmosphere. Above an altitude of 900 m a. s. l., an abnormal release of radon occurs in winter, when the mine air is warmer than the surrounding atmosphere. At the altitudes below 900 m the cold radon rich air blows from the adit mouths in summer. During mine air discharge, radon concentrations in the open atmosphere locally around the adit mouth reach 600,000 Bq m-3, averaging 50,000-250,000 Bq m-3. The temporal pattern of radon fluctuations in fault zones and at the adit mouths is similar. A very close correlation between radon levels and atmospheric air temperature was observed both in the fault zone and at the adits mouths. It indicates that radon release in both cases are caused by a single mechanism. This mechanism probably is the atmospheric air circulation in shallow permeable zones due to the temperature difference between the inside mountain and ambient atmosphere.


Asunto(s)
Contaminantes Radiactivos del Aire , Monitoreo de Radiación , Radón , Uranio , Radón/análisis , Contaminantes Radiactivos del Aire/análisis , Suelo
12.
J Exp Med ; 219(12)2022 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-36121415

RESUMEN

Small intestinal villi are structural and functional units present in higher vertebrates and uniquely adapted to nutrient absorption. Villus enterocytes are organized in transcriptional "zones" dedicated to specialized tasks such as absorption of specific nutrients. We report that the transcription factor c-MAF is expressed in differentiated lower and mid-villus enterocytes and is a target of BMP signaling. Maf inactivation perturbed the villus zonation program by increasing carbohydrate-related transcripts while suppressing transcripts linked to amino-acid and lipid absorption. The formation of cytoplasmic lipid droplets, shuttling dietary fat to chylomicrons, was impaired upon Maf loss indicating its role in dietary lipid handling. Maf inactivation under homeostatic conditions expanded tuft cells and led to compensatory gut lengthening, preventing weight loss. However, delayed Maf-/- enterocyte maturation impaired weight recovery after acute intestinal injury, resulting in reduced survival. Our results identify c-MAF as a regulator of the intestinal villus zonation program, while highlighting the importance of coordination between stem/progenitor and differentiation programs for intestinal regeneration.


Asunto(s)
Quilomicrones , Enterocitos , Animales , Carbohidratos , Grasas de la Dieta , Nutrientes , Factores de Transcripción
13.
Front Cell Infect Microbiol ; 12: 941860, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36034709

RESUMEN

The lymphatic system plays a crucial role in mounting immune response against intracellular pathogens, and recent studies have documented its role in facilitating tumor dissemination linked largely with cancer cells. However, in mucocutaneous leishmaniasis (MCL) caused by Leishmania Viannia subgenus showing infectious metastasis and resulting in severe distant secondary lesions, the route of escape of these parasites to secondary sites has not yet been investigated in detail. Our results demonstrated that when infection was associated with inflammation and additionally exacerbated by the presence of dsRNA viral endosymbiont (LRV1), lymphatic vessels could serve as efficient routes for infected cells to egress from the primary site and colonize distant organs. We challenged this hypothesis by using the intracellular Leishmania protozoan parasites Leishmania guyanensis (Lgy) associated with or without a dsRNA viral endosymbiont, exacerbating the infection and responsible for a strong inflammatory response, and favoring metastasis of the infection. We analyzed possible cargo cells and the routes of dissemination through flow cytometry, histological analysis, and in vivo imaging in our metastatic model to show that parasites disseminated not only intracellularly but also as free extracellular parasites using migrating immune cells, lymph nodes (LNs), and lymph vessels, and followed intricate connections of draining and non-draining lymph node to finally end up in the blood and in distant skin, causing new lesions.


Asunto(s)
Leishmania braziliensis , Leishmania , Leishmaniasis Mucocutánea , Neoplasias , Humanos , Sistema Linfático
14.
Environ Sci Pollut Res Int ; 29(59): 88606-88617, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35836048

RESUMEN

This article delves into the factors that may influence radon flux, such as soil properties and weather conditions, on the example of two experimental locations with different soil compositions, composed primarily of clay and sand, respectively. The experimental location with sandy soil was previously observed to have anomalously high radon flux levels. Radon monitoring was performed routinely, approximately at the same time of day and in parallel on both of these locations to exclude the influence of diurnal variations. The results show that radon transport in these locations differs in mechanism: Location with clay soil has diffusive radon transport, with an average radon flux density of 37.4 ± 24.9 mBq m-2 s-1 and a range of 0.3-167.8 mBq m-2 s-1, while the location with sandy soil has convective radon transport with an average radon flux density of 93.6 ± 51.2 mBq m-2 s-1 and a range of 9.8-302.2 mBq m-2 s-1. This corresponds to about 8.3% of RFD measurements on site with clay soils exceeding the national reference level of 80 mBq m-2 s-1 and 45.6% exceeding them on the site with sandy soils. Average radon flux density values were then compared to meteorological variables using Pearson correlation analysis with Student's t-test. It was observed that radon flux density correlates the most with ambient air temperature both for diffusive and convective radon transport mechanisms, while a weaker inverse correlation is observed with atmospheric precipitation and wind speed for the diffusive mode of radon transport, but not for the convective. Radon activity concentration in soil air correlates with the radon flux density and air temperature in the case of convective radon transport, but does not correlate in the case of diffusive transport.


Asunto(s)
Contaminantes Radiactivos del Aire , Monitoreo de Radiación , Radón , Contaminantes Radiactivos del Suelo , Humanos , Radón/análisis , Suelo , Arcilla , Moscú , Contaminantes Radiactivos del Suelo/análisis , Viento , Monitoreo de Radiación/métodos , Contaminantes Radiactivos del Aire/análisis
15.
Acta Crystallogr D Struct Biol ; 78(Pt 7): 825-834, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35775982

RESUMEN

The resistance of bacteria to ß-lactam antibiotics is primarily caused by the production of ß-lactamases. Here, novel crystal structures of the native ß-lactamase TEM-171 and two complexes with the widely used inhibitor tazobactam are presented, alongside complementary data from UV spectroscopy and fluorescence quenching. The six chemically identical ß-lactamase molecules in the crystallographic asymmetric unit displayed different degrees of disorder. The tazobactam intermediate was covalently bound to the catalytic Ser70 in the trans-enamine configuration. While the conformation of tazobactam in the first complex resembled that in published ß-lactamase-tazobactam structures, in the second complex, which was obtained after longer soaking of the native crystals in the inhibitor solution, a new and previously unreported tazobactam conformation was observed. It is proposed that the two complexes correspond to different stages along the deacylation path of the acyl-enzyme intermediate. The results provide a novel structural basis for the rational design of new ß-lactamase inhibitors.


Asunto(s)
Ácido Penicilánico , beta-Lactamasas , Cristalografía por Rayos X , Inhibidores Enzimáticos/química , Ácido Penicilánico/química , Ácido Penicilánico/metabolismo , Ácido Penicilánico/farmacología , Tazobactam , beta-Lactamasas/química
16.
Nat Commun ; 13(1): 3983, 2022 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-35810168

RESUMEN

The small intestinal villus tip is the first point of contact for lumen-derived substances including nutrients and microbial products. Electron microscopy studies from the early 1970s uncovered unusual spatial organization of small intestinal villus tip blood vessels: their exterior, epithelial-facing side is fenestrated, while the side facing the villus stroma is non-fenestrated, covered by pericytes and harbors endothelial nuclei. Such organization optimizes the absorption process, however the molecular mechanisms maintaining this highly specialized structure remain unclear. Here we report that perivascular LGR5+ villus tip telocytes (VTTs) are necessary for maintenance of villus tip endothelial cell polarization and fenestration by sequestering VEGFA signaling. Mechanistically, unique VTT expression of the protease ADAMTS18 is necessary for VEGFA signaling sequestration through limiting fibronectin accumulation. Therefore, we propose a model in which LGR5+ ADAMTS18+ telocytes are necessary to maintain a "just-right" level and location of VEGFA signaling in intestinal villus blood vasculature to ensure on one hand the presence of sufficient endothelial fenestrae, while avoiding excessive leakiness of the vessels and destabilization of villus tip epithelial structures.


Asunto(s)
Intestinos , Telocitos , Duodeno , Mucosa Intestinal/metabolismo , Nutrientes
17.
Polymers (Basel) ; 14(11)2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35683927

RESUMEN

The sorption-diffusion characteristics of rigid-chain glassy polymers based on polyheteroarylenes (PHAs) have been studied in a wide interval of relative humidity and temperatures of thermal treatment of the polymer sorbents. Experimental data on water vapor sorption for polynaphthoyleneimidobenzimidazole (PNIB) and its copolymers with different chemical nature have been obtained. Water diffusion coefficients have been calculated, and parameters of their concentration and temperature dependences have been determined. It was found that water molecules sorbed by PNIB and its copolymers are strongly bounded. Water mobile and cluster states depend on the structure of macromolecules and thermal prehistory of polymer sorbents. It is shown that the translational coefficients of water diffusion for all PHAs are in the range from 10-9 to 10-8 cm2/s. The diffusion coefficients also increase slightly with temperature increasing, and their general dependence on temperature is satisfactorily described by the Arrhenius equation. The average activation energy of water diffusion varies from 24.3 to 25.9 kJ/mol. The hydrate numbers of rigid-chain PHAs functional groups have been determined. The above-mentioned results allow us to predict the sorption properties of heterocyclic macromolecular sorbents with complex chain architecture.

18.
Sci Adv ; 8(23): eabl5162, 2022 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-35675399

RESUMEN

Tumor-associated lymphatic vessels promote metastasis and regulate antitumor immune responses. Here, we assessed the impact of cytotoxic T cells on the local lymphatic vasculature and concomitant tumor dissemination during an antitumor response. Interferon-γ (IFN-γ) released by effector T cells enhanced the expression of immunosuppressive markers by tumor-associated lymphatic endothelial cells (LECs). However, at higher effector T cell densities within the tumor, T cell-based immunotherapies induced LEC apoptosis and decreased tumor lymphatic vessel density. As a consequence, lymphatic flow was impaired, and lymph node metastasis was reduced. Mechanistically, T cell-mediated tumor cell death induced the release of tumor antigens and cross-presentation by tumor LECs, resulting in antigen-specific LEC killing by T cells. When LECs lacked the IFN-γ receptor expression, LEC killing was abrogated, indicating that IFN-γ is indispensable for reducing tumor-associated lymphatic vessel density and drainage. This study provides insight into how cytotoxic T cells modulate tumor lymphatic vessels and may help to improve immunotherapeutic protocols.


Asunto(s)
Células Endoteliales , Interferón gamma , Antígenos de Neoplasias , Reactividad Cruzada , Células Endoteliales/metabolismo , Humanos , Interferón gamma/metabolismo , Metástasis Linfática
19.
Immunity ; 55(7): 1250-1267.e12, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35709757

RESUMEN

The intestine harbors a large population of resident eosinophils, yet the function of intestinal eosinophils has not been explored. Flow cytometry and whole-mount imaging identified eosinophils residing in the lamina propria along the length of the intestine prior to postnatal microbial colonization. Microscopy, transcriptomic analysis, and mass spectrometry of intestinal tissue revealed villus blunting, altered extracellular matrix, decreased epithelial cell turnover, increased gastrointestinal motility, and decreased lipid absorption in eosinophil-deficient mice. Mechanistically, intestinal epithelial cells released IL-33 in a microbiota-dependent manner, which led to eosinophil activation. The colonization of germ-free mice demonstrated that eosinophil activation in response to microbes regulated villous size alterations, macrophage maturation, epithelial barrier integrity, and intestinal transit. Collectively, our findings demonstrate a critical role for eosinophils in facilitating the mutualistic interactions between the host and microbiota and provide a rationale for the functional significance of their early life recruitment in the small intestine.


Asunto(s)
Enfermedades Transmisibles , Microbiota , Animales , Eosinófilos , Homeostasis , Mucosa Intestinal , Intestino Delgado , Ratones
20.
Nat Cardiovasc Res ; 1(5): 476-490, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35602406

RESUMEN

Stem and progenitor cells residing in the intestinal crypts drive the majority of colorectal cancers (CRCs), yet vascular contribution to this niche remains largely unexplored. VEGFA is a key driver of physiological and tumor angiogenesis. Accordingly, current anti-angiogenic cancer therapies target the VEGFA pathway. Here we report that in CRC expansion of the stem/progenitor pool in intestinal crypts requires VEGFA-independent growth and remodeling of blood vessels. Epithelial transformation induced expression of the endothelial peptide apelin, directs migration of distant venous endothelial cells towards progenitor niche vessels ensuring optimal perfusion. In the absence of apelin, loss of injury-inducible PROX1+ epithelial progenitors inhibited both incipient and advanced intestinal tumor growth. Our results establish fundamental principles for the reciprocal communication between vasculature and the intestinal progenitor niche and provide a mechanism for resistance to VEGFA-targeting drugs in CRCs.

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