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1.
IEEE Internet Things J ; 11(9): 16148-16157, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38765485

RESUMEN

Light exposure is a vital regulator of physiology and behavior in humans. However, monitoring of light exposure is not included in current wearable Internet of Things (IoT) devices, and only recently have international standards defined [Formula: see text] -optic equivalent daylight illuminance (EDI) measures for how the eye responds to light. This article reports a wearable light sensor node that can be incorporated into the IoT to provide monitoring of EDI exposure in real-world settings. We present the system design, electronic performance testing, and accuracy of EDI measurements when compared to a calibrated spectral source. This includes consideration of the directional response of the sensor, and a comparison of performance when placed on different parts of the body, and a demonstration of practical use over 7 days. Our device operates for 3.5 days between charges, with a sampling period of 30 s. It has 10 channels of measurement, over the range 415-910 nm, balancing accuracy and cost considerations. Measured [Formula: see text]-opic EDI results for 13 devices show a mean absolute error of less than 0.07 log lx, and a minimum between device correlation of 0.99. These findings demonstrate that accurate light sensing is feasible, including at wrist worn locations. We provide an experimental platform for use in future investigations in real-world light exposure monitoring and IoT-based lighting control.

2.
Cell Rep ; 42(12): 113502, 2023 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-38032796

RESUMEN

Optogenetics is a rapidly advancing technology combining photochemical, optical, and synthetic biology to control cellular behavior. Together, sensitive light-responsive optogenetic tools and human pluripotent stem cell differentiation models have the potential to fine-tune differentiation and unpick the processes by which cell specification and tissue patterning are controlled by morphogens. We used an optogenetic bone morphogenetic protein (BMP) signaling system (optoBMP) to drive chondrogenic differentiation of human embryonic stem cells (hESCs). We engineered light-sensitive hESCs through CRISPR-Cas9-mediated integration of the optoBMP system into the AAVS1 locus. The activation of optoBMP with blue light, in lieu of BMP growth factors, resulted in the activation of BMP signaling mechanisms and upregulation of a chondrogenic phenotype, with significant transcriptional differences compared to cells in the dark. Furthermore, cells differentiated with light could form chondrogenic pellets consisting of a hyaline-like cartilaginous matrix. Our findings indicate the applicability of optogenetics for understanding human development and tissue engineering.


Asunto(s)
Optogenética , Células Madre Pluripotentes , Humanos , Condrocitos , Diferenciación Celular/genética , Cartílago/metabolismo , Condrogénesis/genética , Proteína Morfogenética Ósea 2/metabolismo , Células Cultivadas
3.
Pflugers Arch ; 475(12): 1387-1407, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38036775

RESUMEN

Animal opsins are light activated G-protein-coupled receptors, capable of optogenetic control of G-protein signalling for research or therapeutic applications. Animal opsins offer excellent photosensitivity, but their temporal resolution can be limited by long photoresponse duration when expressed outside their native cellular environment. Here, we explore methods for addressing this limitation for a prototypical animal opsin (human rod opsin) in HEK293T cells. We find that the application of the canonical rhodopsin kinase (GRK1)/visual arrestin signal termination mechanism to this problem is complicated by a generalised suppressive effect of GRK1 expression. This attenuation can be overcome using phosphorylation-independent mutants of arrestin, especially when these are tethered to the opsin protein. We further show that point mutations targeting the Schiff base stability of the opsin can also reduce signalling lifetime. Finally, we apply one such mutation (E122Q) to improve the temporal fidelity of restored visual responses following ectopic opsin expression in the inner retina of a mouse model of retinal degeneration (rd1). Our results reveal that these two strategies (targeting either arrestin binding or Schiff-base hydrolysis) can produce more time-delimited opsin signalling under heterologous expression and establish the potential of this approach to improve optogenetic performance.


Asunto(s)
Opsinas , Opsinas de Bastones , Animales , Ratones , Humanos , Opsinas de Bastones/genética , Opsinas de Bastones/metabolismo , Opsinas/genética , Opsinas/metabolismo , Optogenética/métodos , Células HEK293 , Arrestinas/genética , Arrestinas/metabolismo
4.
J Physiol ; 601(21): 4737-4749, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37777993

RESUMEN

Many neurons of the mammalian master circadian oscillator in the suprachiasmatic nuclei (SCN) respond to light pulses with irradiance-dependent changes in firing. Here, we set out to better understand this irradiance coding ability by considering how the SCN tracks more continuous changes in irradiance at both population and single unit level. To this end, we recorded extracellular activity in the SCN of anaesthetised mice presented with up + down irradiance staircase stimuli covering moonlight to daylight conditions and incorporating epochs with steady light or superimposed higher frequency modulations (temporal white noise (WN) and frequency/contrast chirps). Single unit activity was extracted by spike sorting. The population response of SCN units to this stimulus was a progressive increase in firing rate at higher irradiances. This relationship was symmetrical for up vs. down phases of the ramp in the presence of white noise or chirps but exhibited hysteresis for steady light, with firing systematically higher during increasing irradiance. Single units also showed a monotonic relationship between firing and irradiance but exhibited diversity not only in response polarity (increases vs. decreases in firing), but also in the sensitivity (EC50 ) and slope of fitted functions. These data show that individual SCN neurons exhibit monotonic relationships between irradiance and firing rate but differ in the irradiance range over which they respond. This property may help the SCN to encode the large differences in irradiance found in nature using neurons with a constrained range of firing rates. KEY POINTS: Daily changes in environmental light (irradiance) entrain the suprachiasmatic nucleus (SCN) circadian clock. The mouse SCN shows graded increases in neurophysiological activity with light pulses of increasing irradiance. We show that this monotonic relationship between firing rate and irradiance is retained at population and single unit level when probed with more naturalistic staircase increases and decreases in irradiance. The irradiance response is more reliable in the presence of ongoing higher temporal frequency modulations in light intensity than under steady light. Single units varied in sensitivity allowing the population to cover a wide range of irradiances. Irradiance coding in the SCN has characteristics of a sparse code with individual neurons tracking different portions of the natural irradiance range. This property may address the challenge of encoding a 109 -fold day:night difference in irradiance within the constrained range of firing rates available to individual neurons.


Asunto(s)
Relojes Circadianos , Ritmo Circadiano , Ratones , Animales , Ritmo Circadiano/fisiología , Núcleo Supraquiasmático/fisiología , Neuronas/fisiología , Luz , Mamíferos
5.
Front Cell Neurosci ; 17: 1114634, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36993934

RESUMEN

Introduction: Intrinsically photosensitive retinal ganglion cells (ipRGCs) integrate melanopsin and rod/cone-mediated inputs to signal to the brain. Whilst originally identified as a cell type specialised for encoding ambient illumination, several lines of evidence indicate a strong association between colour discrimination and ipRGC-driven responses. Thus, cone-mediated colour opponent responses have been widely found across ipRGC target regions in the mouse brain and influence a key ipRGC-dependent function, circadian photoentrainment. Although ipRGCs exhibiting spectrally opponent responses have also been identified, the prevalence of such properties have not been systematically evaluated across the mouse retina or yet been found in ipRGC subtypes known to influence the circadian system. Indeed, there is still uncertainty around the overall prevalence of cone-dependent colour opponency across the mouse retina, given the strong retinal gradient in S and M-cone opsin (co)-expression and overlapping spectral sensitivities of most mouse opsins. Methods: To address this, we use photoreceptor isolating stimuli in multielectrode recordings from human red cone opsin knock-in mouse (Opn1mwR) retinas to systematically survey cone mediated responses and the occurrence of colour opponency across ganglion cell layer (GCL) neurons and identify ipRGCs based on spectral comparisons and/or the persistence of light responses under synaptic blockade. Results: Despite detecting robust cone-mediated responses across the retina, we find cone opponency is rare, especially outside of the central retina (overall ~3% of GCL neurons). In keeping with previous suggestions we also see some evidence of rod-cone opponency (albeit even more rare under our experimental conditions), but find no evidence for any enrichment of cone (or rod) opponent responses among functionally identified ipRGCs. Conclusion: In summary, these data suggest the widespread appearance of cone-opponency across the mouse early visual system and ipRGC-related responses may be an emergent feature of central visual processing mechanisms.

6.
Viruses ; 15(2)2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36851537

RESUMEN

Human cytomegalovirus (CMV) infection drives the expansion and differentiation of natural killer (NK) cells with adaptive-like features. We investigated whether age and time on antiretroviral therapy (ART) influenced adaptive NK cell frequency and functionality. Flow cytometry was used to evaluate the frequency of adaptive and conventional NK cells in 229 CMV+ individuals of whom 170 were people living with HIV (PLWH). The frequency of these NK cell populations producing CD107a, CCL4, IFN-γ or TNF-α was determined following a 6-h antibody dependent (AD) stimulation. Though ART duration and age were correlated, longer time on ART was associated with a reduced frequency of adaptive NK cells. In general, the frequency and functionality of NK cells following AD stimulation did not differ significantly between treated CMV+PLWH and CMV+HIV- persons, suggesting that HIV infection, per se, did not compromise AD NK cell function. AD activation of adaptive NK cells from CMV+PLWH induced lower frequencies of IFN-γ or TNF-α secreting cells in older persons, when compared with younger persons.


Asunto(s)
Coinfección , Infecciones por Citomegalovirus , Infecciones por VIH , Anciano , Anciano de 80 o más Años , Humanos , Infecciones por Citomegalovirus/complicaciones , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Células Asesinas Naturales , Factor de Necrosis Tumoral alfa , Antígenos CD57/inmunología
7.
Biomolecules ; 13(2)2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36830738

RESUMEN

Atopic dermatitis (AD) is known as a skin disease; however, T cell immunopathology found in blood is associated with its severity. Skin Staphylococcus aureus (S. aureus) and associated host-pathogen dynamics are important to chronic T helper 2 (Th2)-dominated inflammation in AD, yet they remain poorly understood. This study sought to investigate the effects of S. aureus-derived molecules and skin alarmins on human peripheral blood mononuclear cells, specifically testing Th2-type cells, cytokines, and chemokines known to be associated with AD. We first show that six significantly elevated Th2-related chemokine biomarkers distinguish blood from adult AD patients compared to healthy controls ex vivo; in addition, TARC/CCL17, LDH, and PDGF-AA/AB correlated significantly with disease severity. We then demonstrate that these robust AD-associated biomarkers, as well as associated type 2 T cell functions, are readily reproduced from healthy blood mononuclear cells exposed to the alarmin TSLP and the S. aureus superantigen SEB in a human in vitro model, including IL-13, IL-5, and TARC secretion as well as OX-40-expressing activated memory T cells. We further show that the agonism of nucleotide-binding oligomerization domain-containing protein (NOD)2 inhibits this IL-13 secretion and memory Th2 and Tc2 cell functional activation while inducing significantly increased pSTAT3 and IL-6, both critical for Th17 cell responses. These findings identify NOD2 as a potential regulator of type 2 immune responses in humans and highlight its role as an endogenous inhibitor of pathogenic IL-13 that may open avenues for its therapeutic targeting in AD.


Asunto(s)
Dermatitis Atópica , Adulto , Humanos , Dermatitis Atópica/tratamiento farmacológico , Interleucina-13/metabolismo , Leucocitos Mononucleares/metabolismo , Staphylococcus aureus/metabolismo , Citocinas/metabolismo , Quimiocinas/metabolismo , Biomarcadores , Proteína Adaptadora de Señalización NOD2/metabolismo
8.
Sci Rep ; 13(1): 155, 2023 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-36599877

RESUMEN

A key step in understanding animal behaviour relies in the ability to quantify poses and movements. Methods to track body landmarks in 2D have made great progress over the last few years but accurate 3D reconstruction of freely moving animals still represents a challenge. To address this challenge here we develop the 3D-UPPER algorithm, which is fully automated, requires no a priori knowledge of the properties of the body and can also be applied to 2D data. We find that 3D-UPPER reduces by [Formula: see text] fold the error in 3D reconstruction of mouse body during freely moving behaviour compared with the traditional triangulation of 2D data. To achieve that, 3D-UPPER performs an unsupervised estimation of a Statistical Shape Model (SSM) and uses this model to constrain the viable 3D coordinates. We show, by using simulated data, that our SSM estimator is robust even in datasets containing up to 50% of poses with outliers and/or missing data. In simulated and real data SSM estimation converges rapidly, capturing behaviourally relevant changes in body shape associated with exploratory behaviours (e.g. with rearing and changes in body orientation). Altogether 3D-UPPER represents a simple tool to minimise errors in 3D reconstruction while capturing meaningful behavioural parameters.


Asunto(s)
Algoritmos , Imagenología Tridimensional , Animales , Ratones , Imagenología Tridimensional/métodos , Movimiento , Conducta Animal
9.
Medicine (Baltimore) ; 101(38): e30794, 2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36197157

RESUMEN

The objective of this study was to evaluate whether adaptive NKG2C+CD57+ natural killer (adapNK) cell frequencies are associated with pre-clinical coronary atherosclerosis in participants of the Canadian HIV and Aging Cohort Study. This cross-sectional study included 194 Canadian HIV and Aging Cohort Study participants aged ≥ 40 years of which 128 were cytomegalovirus (CMV)+ people living with HIV (PLWH), 8 were CMV-PLWH, 37 were CMV mono-infected individuals, and 21 were neither human immunodeficiency virus nor CMV infected. Participants were evaluated for the frequency of their adapNK cells and total plaque volume (TPV). TPV was assessed using cardiac computed tomography. Participants were classified as free of, or having, coronary atherosclerosis if their TPV was "0" and ">0," respectively. The frequency of adapNK cells was categorized as low, intermediate or high if they constituted <4.6%, between ≥4.6% and 20% and >20%, respectively, of the total frequency of CD3-CD56dim NK cells. The association between adapNK cell frequency and TPV was assessed using an adjusted Poisson regression analysis. A greater proportion of CMV+PLWH with TPV = 0 had high adapNK cell frequencies than those with TPV > 0 (61.90% vs 39.53%, P = .03) with a similar non-significant trend for CMV mono-infected participants (46.15% vs 34.78%). The frequency of adapNK cells was negatively correlated with TPV. A high frequency of adapNK cells was associated with a relative risk of 0.75 (95% confidence intervals 0.58, 0.97, P = .03) for presence of coronary atherosclerosis. This observation suggests that adapNK cells play a protective role in the development of coronary atherosclerotic plaques.


Asunto(s)
Enfermedad de la Arteria Coronaria , Infecciones por Citomegalovirus , Infecciones por VIH , Placa Aterosclerótica , Canadá/epidemiología , Estudios de Cohortes , Estudios Transversales , Citomegalovirus , Infecciones por Citomegalovirus/complicaciones , Infecciones por VIH/complicaciones , Humanos , Células Asesinas Naturales , Subfamília C de Receptores Similares a Lectina de Células NK , Placa Aterosclerótica/diagnóstico por imagen
11.
Philos Trans A Math Phys Eng Sci ; 380(2233): 20210299, 2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-35965467

RESUMEN

We report on an ongoing collaboration between epidemiological modellers and visualization researchers by documenting and reflecting upon knowledge constructs-a series of ideas, approaches and methods taken from existing visualization research and practice-deployed and developed to support modelling of the COVID-19 pandemic. Structured independent commentary on these efforts is synthesized through iterative reflection to develop: evidence of the effectiveness and value of visualization in this context; open problems upon which the research communities may focus; guidance for future activity of this type and recommendations to safeguard the achievements and promote, advance, secure and prepare for future collaborations of this kind. In describing and comparing a series of related projects that were undertaken in unprecedented conditions, our hope is that this unique report, and its rich interactive supplementary materials, will guide the scientific community in embracing visualization in its observation, analysis and modelling of data as well as in disseminating findings. Equally we hope to encourage the visualization community to engage with impactful science in addressing its emerging data challenges. If we are successful, this showcase of activity may stimulate mutually beneficial engagement between communities with complementary expertise to address problems of significance in epidemiology and beyond. See https://ramp-vis.github.io/RAMPVIS-PhilTransA-Supplement/. This article is part of the theme issue 'Technical challenges of modelling real-life epidemics and examples of overcoming these'.


Asunto(s)
COVID-19 , Pandemias , COVID-19/epidemiología , Humanos
12.
Viruses ; 14(6)2022 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-35746615

RESUMEN

Some people, known as HIV-exposed seronegative (HESN) individuals, remain uninfected despite high levels of exposure to HIV. Understanding the mechanisms underlying their apparent resistance to HIV infection may inform strategies designed to protect against HIV infection. Natural Killer (NK) cells are innate immune cells whose activation state depends on the integration of activating and inhibitory signals arising from cell surface receptors interacting with their ligands on neighboring cells. Inhibitory NK cell receptors use a subset of major histocompatibility (MHC) class I antigens as ligands. This interaction educates NK cells, priming them to respond to cells with reduced MHC class I antigen expression levels as occurs on HIV-infected cells. NK cells can interact with both autologous HIV-infected cells and allogeneic cells bearing MHC antigens seen as non self by educated NK cells. NK cells are rapidly activated upon interacting with HIV-infected or allogenic cells to elicit anti-viral activity that blocks HIV spread to new target cells, suppresses HIV replication, and kills HIV-infected cells before HIV reservoirs can be seeded and infection can be established. In this manuscript, we will review the epidemiological and functional evidence for a role for NK cells in protection from HIV infection.


Asunto(s)
Infecciones por VIH , VIH-1 , Linfocitos T CD4-Positivos , VIH-1/fisiología , Antígenos de Histocompatibilidad Clase I , Humanos , Células Asesinas Naturales , Ligandos
13.
Front Immunol ; 13: 879124, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35720328

RESUMEN

Infection with the human immunodeficiency virus (HIV), when left untreated, typically leads to disease progression towards acquired immunodeficiency syndrome. Some people living with HIV (PLWH) control their virus to levels below the limit of detection of standard viral load assays, without treatment. As such, they represent examples of a functional HIV cure. These individuals, called Elite Controllers (ECs), are rare, making up <1% of PLWH. Genome wide association studies mapped genes in the major histocompatibility complex (MHC) class I region as important in HIV control. ECs have potent virus specific CD8+ T cell responses often restricted by protective MHC class I antigens. Natural Killer (NK) cells are innate immune cells whose activation state depends on the integration of activating and inhibitory signals arising from cell surface receptors interacting with their ligands on neighboring cells. Inhibitory NK cell receptors also use a subset of MHC class I antigens as ligands. This interaction educates NK cells, priming them to respond to HIV infected cell with reduced MHC class I antigen expression levels. NK cells can also be activated through the crosslinking of the activating NK cell receptor, CD16, which binds the fragment crystallizable portion of immunoglobulin G. This mode of activation confers NK cells with specificity to HIV infected cells when the antigen binding portion of CD16 bound immunoglobulin G recognizes HIV Envelope on infected cells. Here, we review the role of NK cells in antibody independent and antibody dependent HIV control.


Asunto(s)
Infecciones por VIH , VIH-1 , Estudio de Asociación del Genoma Completo , Antígenos HLA , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Inmunoglobulina G/genética , Células Asesinas Naturales , Ligandos , Receptores de Células Asesinas Naturales/genética
14.
Virologie (Montrouge) ; 26(1): 73-89, 2022 01 01.
Artículo en Francés | MEDLINE | ID: mdl-35766088

RESUMEN

Résumé En l'absence de traitement antirétroviral, l'infection par le VIH progresse normalement vers le syndrome d'immunodéficience acquise. Une minorité de sujets infectés par le VIH sont toutefois capables de contrôler la réplication virale en l'absence de traitement. Ces patients appelés sujets contrôleurs d'élite (EC pour elite controllers) représentent un exemple de guérison fonctionnelle de l'infection par le VIH. Certains EC sont infectés par des virus défectifs, alors que d'autres ont des provirus intégrés dans des zones non transcrites de la chromatine. Cependant, la plupart des EC se distinguent des sujets non-contrôleurs parce qu'ils développent de fortes réponses T CD4 et CD8 spécifiques au VIH. Les cellules tueuses naturelles (NK pour Natural Killer) sont des cellules du système immunitaire inné qui fonctionnent à l'interface entre l'immunité innée et l'immunité acquise. Les cellules NK sont capables de reconnaître et de répondre à des cellules infectées dès les stades précoces de l'infection. Les cellules NK peuvent être activées de fac¸on indépendante et dépendante des anticorps afin d'exercer des fonctions antivirales et éliminer les cellules infectées. Ce manuscrit discutera du rôle des cellules NK dans le contrôle de l'infection par le VIH.


Asunto(s)
Controladores de Élite , Infecciones por VIH , Humanos , Células Asesinas Naturales
15.
Virologie (Montrouge) ; 26(1): 34-49, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-35766089

RESUMEN

Untreated HIV infection usually leads to disease progression and development of the acquired immunodeficiency syndrome. A rare subset of people living with HIV control HIV without anti-retroviral therapy. These individuals, known as Elite Controllers (ECs), represent examples of a functional HIV cure. ECs differ from non-controllers is many aspects. Some are infected with defective virus, most have potent CD4 and CD8 virus-specific T cell responses and proviruses in these individuals tend to be inserted into regions with characteristics of deep latency. Natural Killer (NK) cells are innate immune cells that function at the intersection of innate and adaptive immunity. They have the capacity to recognize and respond to HIV-infected cells from the earliest stages in infection. NK cells can be activated through antibody independent and antibody dependent mechanisms to elicit functions that control HIV and kill infected cells. This manuscript will review the role of NK cells in HIV control.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Infecciones por VIH , Inmunidad Adaptativa , Controladores de Élite , Infecciones por VIH/tratamiento farmacológico , Humanos , Células Asesinas Naturales
16.
Methods Mol Biol ; 2407: 173-186, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34985665

RESUMEN

Early establishment of HIV reservoir represents the main impediment to an HIV cure. Mainly composed of infected memory CD4 T-cells and macrophages, HIV reservoirs are found in several organs including lymph nodes, gut, and testes. In men, and as seen in brain and eyes, testes represent a distinctive organ characterized by an immune privilege, allowing the tolerance of spermatozoa which only develop after puberty, long after the establishment of systemic immunity. The immune privilege of testes relies on a strict testis-blood barrier, and a local immunosuppressive environment. Testes has been described as reservoir for several viruses including Ebola, Zika, and HIV. Indeed, HIV reservoirs were detected in tested viremic and virally suppressed donor taking antiretroviral therapy (ART). Herein, we discuss the distinctive environment found in human testes and describe a validated method allowing the characterization and quantification of HIV-infected CD4 T-cells in human testes. Using mechanical and enzymatic treatment, cells can be extracted from human testis samples. Characterization of those cells can be performed by flow cytometry and HIV reservoir quantification performed by nested qPCR after flow cytometry sorting.


Asunto(s)
Infecciones por VIH , Infección por el Virus Zika , Virus Zika , Linfocitos T CD4-Positivos , Citometría de Flujo , Humanos , Tolerancia Inmunológica , Macrófagos , Masculino , Testículo , Carga Viral , Latencia del Virus
17.
Cardiovasc Res ; 118(5): 1262-1275, 2022 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-33909875

RESUMEN

AIMS: Hepatic capillaries are lined with specialized liver sinusoidal endothelial cells (LSECs) which support macromolecule passage to hepatocytes and prevent fibrosis by keeping hepatic stellate cells (HSCs) quiescent. LSEC specialization is co-determined by transcription factors. The zinc-finger E-box-binding homeobox (Zeb)2 transcription factor is enriched in LSECs. Here, we aimed to elucidate the endothelium-specific role of Zeb2 during maintenance of the liver and in liver fibrosis. METHODS AND RESULTS: To study the role of Zeb2 in liver endothelium we generated EC-specific Zeb2 knock-out (ECKO) mice. Sequencing of liver EC RNA revealed that deficiency of Zeb2 results in prominent expression changes in angiogenesis-related genes. Accordingly, the vascular area was expanded and the presence of pillars inside ECKO liver vessels indicated that this was likely due to increased intussusceptive angiogenesis. LSEC marker expression was not profoundly affected and fenestrations were preserved upon Zeb2 deficiency. However, an increase in continuous EC markers suggested that Zeb2-deficient LSECs are more prone to dedifferentiation, a process called 'capillarization'. Changes in the endothelial expression of ligands that may be involved in HSC quiescence together with significant changes in the expression profile of HSCs showed that Zeb2 regulates LSEC-HSC communication and HSC activation. Accordingly, upon exposure to the hepatotoxin carbon tetrachloride (CCl4), livers of ECKO mice showed increased capillarization, HSC activation, and fibrosis compared to livers from wild-type littermates. The vascular maintenance and anti-fibrotic role of endothelial Zeb2 was confirmed in mice with EC-specific overexpression of Zeb2, as the latter resulted in reduced vascularity and attenuated CCl4-induced liver fibrosis. CONCLUSION: Endothelial Zeb2 preserves liver angioarchitecture and protects against liver fibrosis. Zeb2 and Zeb2-dependent genes in liver ECs may be exploited to design novel therapeutic strategies to attenuate hepatic fibrosis.


Asunto(s)
Células Endoteliales , Cirrosis Hepática , Animales , Biomarcadores/metabolismo , Células Endoteliales/metabolismo , Endotelio , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Hígado/metabolismo , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/genética , Cirrosis Hepática/prevención & control , Ratones
18.
Pain ; 163(7): e821-e836, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34913882

RESUMEN

ABSTRACT: The pathophysiology of fibromyalgia syndrome (FMS) remains elusive, leading to a lack of objective diagnostic criteria and targeted treatment. We globally evaluated immune system changes in FMS by conducting multiparametric flow cytometry analyses of peripheral blood mononuclear cells and identified a natural killer (NK) cell decrease in patients with FMS. Circulating NK cells in FMS were exhausted yet activated, evidenced by lower surface expression of CD16, CD96, and CD226 and more CD107a and TIGIT. These NK cells were hyperresponsive, with increased CCL4 production and expression of CD107a when co-cultured with human leukocyte antigen null target cells. Genetic and transcriptomic pathway analyses identified significant enrichment of cell activation pathways in FMS driven by NK cells. Skin biopsies showed increased expression of NK activation ligand, unique long 16-binding protein, on subepidermal nerves of patients FMS and the presence of NK cells near peripheral nerves. Collectively, our results suggest that chronic activation and redistribution of circulating NK cells to the peripheral nerves contribute to the immunopathology associated with FMS.


Asunto(s)
Fibromialgia , Fibromialgia/metabolismo , Citometría de Flujo , Humanos , Células Asesinas Naturales/metabolismo , Leucocitos Mononucleares , Nervios Periféricos
19.
Int J Comput Assist Radiol Surg ; 17(1): 85-95, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34643883

RESUMEN

PURPOSE: Traditional undergraduate radiographer training mixes academic lectures and clinical practice. Our goal is to bridge the current disconnection between theory and practice in a safe environment, avoiding the risk of radiation for both practitioners and patients. To this end, this research proposes a new software to teach diagnostic radiography using real-time interactive X-ray simulation and patient positioning. METHODS: The proposed medical simulator is composed of three main modules. A fast and accurate character animation technique is in charge of simulating the patient positioning phase and adapts their internal anatomy accordingly. gVirtualXRay is an open-source X-ray simulation library and generates the corresponding radiographs in real time. Finally, the courseware allows going through all the diagnostic radiology steps from the patient positioning and the machine configuration to the final image enhancing. RESULTS: A face and content validation study has been conducted; 18 radiology professionals were recruited to evaluate our software using a questionnaire. The results show that our tool is realistic in many ways (72% of the participants agreed that the simulations are visually realistic), useful (67%) and suitable (78%) for teaching X-ray radiography. CONCLUSIONS: The proposed tool allows simulating the most relevant steps of the projectional radiography procedure. The virtual patient posing system and X-ray simulation module execute at interactive rates. These features enable the lectures to show their students the results of good and bad practices in a classroom environment, avoiding radiation risk.


Asunto(s)
Posicionamiento del Paciente , Programas Informáticos , Simulación por Computador , Humanos , Radiografía , Rayos X
20.
J Virol ; 95(24): e0162521, 2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34586863

RESUMEN

People living with HIV (PLWH) develop both anti-envelope-specific antibodies, which bind the closed trimeric HIV envelope present on infected cells, and anti-gp120-specific antibodies, which bind gp120 monomers shed by infected cells and taken up by CD4 on uninfected bystander cells. Both antibodies have an Fc portion that binds to Fc receptors on several types of innate immune cells and stimulates them to develop antiviral functions. Among these Fc-dependent functions (FcDFs) are antibody-dependent (AD) cellular cytotoxicity (ADCC), AD cellular trogocytosis (ADCT), and AD phagocytosis (ADCP). In this study, we assessed the evolution of total immunoglobulin G (IgG), anti-gp120, and anti-envelope IgG antibodies and their FcDFs in plasma samples from antiretroviral therapy (ART)-naive subjects during early HIV infection (28 to 194 days postinfection [DPI]). We found that both the concentrations and FcDFs of anti-gp120 and anti-envelope antibodies increased with time in ART-naive PLWH. Although generated concurrently, anti-gp120-specific antibodies were 20.7-fold more abundant than anti-envelope-specific antibodies, both specificities being strongly correlated with each other and FcDFs. Among the FcDFs, only ADCP activity was inversely correlated with concurrent viral load. PLWH who started ART at >90 DPI showed higher anti-envelope-specific antibody levels and ADCT and ADCP activities than those starting ART at<90 DPI. However, in longitudinally collected samples, ART initiation at >90 DPI was accompanied by a faster decline in anti-envelope-specific antibody levels, which did not translate to a faster decline in FcDFs than for those starting ART at <90 DPI. IMPORTANCE Closed-conformation envelope is expressed on the surface of HIV-infected cells. Antibodies targeting this conformation and that support FcDFs have the potential to control HIV. This study tracked the timing of the appearance and evolution of antibodies to closed-conformation envelope, whose concentration increased over the first 6 months of infection. Antiretroviral therapy (ART) initiation blunts further increases in the concentration of these antibodies and their and FcDFs. However, antibodies to open-conformation envelope also increased with DPI until ART initiation. These antibodies target uninfected bystander cells, which may contribute to loss of uninfected CD4 cells and pathogenicity. This report presents, for the first time, the evolution of antibodies to closed-conformation envelope and their fate on ART. This information may be useful in making decisions on the timing of ART initiation in early HIV infection.


Asunto(s)
Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/inmunología , Receptores Fc/metabolismo , Anticuerpos Neutralizantes/inmunología , Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Línea Celular , VIH-1/inmunología , Humanos , Inmunoglobulina G/inmunología , Fagocitosis/inmunología , Receptores Fc/inmunología , Trogocitosis/inmunología , Carga Viral
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