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1.
Rheumatology (Oxford) ; 54(8): 1464-71, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25784774

RESUMO

OBJECTIVE: An accelerated rate of decline in forced vital capacity (FVC) affects >50% of patients with SSc but data on the variability and determinants of this change are scarce. We sought to identify trajectories of FVC and their associated variables in SSc patients over a 12-year period. METHODS: Clinical and pulmonary function data were retrospectively collected. SSc patients with three or more FVC values were included. Group-based modelling was used to cluster similar FVC patterns into trajectories. Baseline variables were associated with the trajectories using multinomial logistic regression. The effect of CYC on FVC was examined with each trajectory as a time-varying covariate. RESULTS: In 254 SSc patients we identified seven distinct FVC trajectories: very low slow decline (5.5%), very low improve (13.8%), low fast decline (9.5%), low stable (19.7%), low-normal improve (31.1%), normal improve (16.1%) and normal stable (4.3%). Younger age and the presence of pulmonary hypertension, Interstitial lung disease and shortness of breath at baseline significantly increased the odds of declining trajectories vs the reference trajectory (low-normal improve). CYC was associated with FVC improvement in the low fast decline trajectory. CONCLUSION: The course of FVC in SSc was highly variable, with improvement and stability experienced even by those with low baseline FVC. Trajectory modelling was able to identify SSc patients who were most likely to experience FVC decline and thus could be a useful tool for patient management as well as clinical trial design.


Assuntos
Progressão da Doença , Pulmão/fisiopatologia , Modelos Biológicos , Escleroderma Sistêmico/fisiopatologia , Capacidade Vital/fisiologia , Adulto , Estudos de Coortes , Gerenciamento Clínico , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Fatores de Tempo
2.
NPJ Regen Med ; 9(1): 2, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182591

RESUMO

Maintenance of the cellular boundary between airway and alveolar compartments during homeostasis and after injury is essential to prohibit pathological plasticity which can reduce respiratory function. Lung injury and disease can induce either functional alveolar epithelial regeneration or dysplastic formation of keratinized epithelium which does not efficiently contribute to gas exchange. Here we show that Sox2 preserves airway cell identity and prevents fate changes into either functional alveolar tissue or pathological keratinization following lung injury. Loss of Sox2 in airway epithelium leads to a loss of airway epithelial identity with a commensurate gain in alveolar and basal cell identity, in part due to activation of Wnt signaling in secretory cells and increased Trp63 expression in intrapulmonary basal-like progenitors. In idiopathic pulmonary fibrosis, loss of SOX2 expression correlates with increased WNT signaling activity in dysplastic keratinized epithelium. SOX2-deficient dysplastic epithelial cells are also observed in COVID-19 damaged lungs. Thus, Sox2 provides a molecular barrier that suppresses airway epithelial plasticity to prevent acquisition of alveolar or basal cell identity after injury and help guide proper epithelial fate and regeneration.

3.
ACS Nano ; 18(33): 22275-22297, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39105696

RESUMO

Nanomedicine has long pursued the goal of targeted delivery to specific organs and cell types but has yet to achieve this goal with the vast majority of targets. One rare example of success in this pursuit has been the 25+ years of studies targeting the lung endothelium using nanoparticles conjugated to antibodies against endothelial surface molecules. However, here we show that such "endothelial-targeted" nanocarriers also effectively target the lungs' numerous marginated neutrophils, which reside in the pulmonary capillaries and patrol for pathogens. We show that marginated neutrophils' uptake of many of these "endothelial-targeted" nanocarriers is on par with endothelial uptake. This generalizes across diverse nanomaterials and targeting moieties and was even found with physicochemical lung tropism (i.e., without targeting moieties). Further, we observed this in ex vivo human lungs and in vivo healthy mice, with an increase in marginated neutrophil uptake of nanoparticles caused by local or distant inflammation. These findings have implications for nanomedicine development for lung diseases. These data also suggest that marginated neutrophils, especially in the lungs, should be considered a major part of the reticuloendothelial system (RES), with a special role in clearing nanoparticles that adhere to the lumenal surfaces of blood vessels.


Assuntos
Pulmão , Nanopartículas , Neutrófilos , Animais , Neutrófilos/metabolismo , Neutrófilos/imunologia , Humanos , Pulmão/imunologia , Pulmão/metabolismo , Camundongos , Nanopartículas/química , Sistema Fagocitário Mononuclear/metabolismo , Endotélio/metabolismo , Camundongos Endogâmicos C57BL , Nanomedicina
4.
Adv Nanobiomed Res ; 3(3): 2200106, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37266328

RESUMO

Diseases of the pulmonary alveolus, such as pulmonary fibrosis, are leading causes of morbidity and mortality, but exceedingly few drugs are developed for them. A major reason for this gap is that after inhalation, drugs are quickly whisked away from alveoli due to their high perfusion. To solve this problem, the mechanisms by which nano-scale drug carriers dramatically improve lung pharmacokinetics using an inhalable liposome formulation containing nintedanib, an antifibrotic for pulmonary fibrosis, are studied. Direct instillation of liposomes in murine lung increases nintedanib's total lung delivery over time by 8000-fold and lung half life by tenfold, compared to oral nintedanib. Counterintuitively, it is shown that pulmonary surfactant neither lyses nor aggregates the liposomes. Instead, each lung compartment (alveolar fluid, alveolar leukocytes, and parenchyma) elutes liposomes over 24 h, likely serving as "drug depots." After deposition in the surfactant layer, liposomes are transferred over 3-6 h to alveolar leukocytes (which take up a surprisingly minor 1-5% of total lung dose instilled) in a nonsaturable fashion. Further, all cell layers of the lung parenchyma take up liposomes. These and other mechanisms elucidated here should guide engineering of future inhaled nanomedicine for alveolar diseases.

5.
J Clin Invest ; 134(4)2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38127441

RESUMO

Lymphangioleiomyomatosis (LAM) is a progressive cystic lung disease caused by tuberous sclerosis complex 1/2 (TSC1/2) gene mutations in pulmonary mesenchymal cells, resulting in activation of the mechanistic target of rapamycin complex 1 (mTORC1). A subset of patients with LAM develop pulmonary vascular remodeling and pulmonary hypertension. Little, however, is known regarding how LAM cells communicate with endothelial cells (ECs) to trigger vascular remodeling. In end-stage LAM lung explants, we identified EC dysfunction characterized by increased EC proliferation and migration, defective angiogenesis, and dysmorphic endothelial tube network formation. To model LAM disease, we used an mTORC1 gain-of-function mouse model with a Tsc2 KO (Tsc2KO) specific to lung mesenchyme (Tbx4LME-Cre Tsc2fl/fl), similar to the mesenchyme-specific genetic alterations seen in human disease. As early as 8 weeks of age, ECs from mice exhibited marked transcriptomic changes despite an absence of morphological changes to the distal lung microvasculature. In contrast, 1-year-old Tbx4LME-Cre Tsc2fl/fl mice spontaneously developed pulmonary vascular remodeling with increased medial thickness. Single-cell RNA-Seq of 1-year-old mouse lung cells identified paracrine ligands originating from Tsc2KO mesenchyme, which can signal through receptors in arterial ECs. These ECs had transcriptionally altered genes including those in pathways associated with blood vessel remodeling. The proposed pathophysiologic mesenchymal ligand-EC receptor crosstalk highlights the importance of an altered mesenchymal cell/EC axis in LAM and other hyperactive mTORC1-driven diseases. Since ECs in patients with LAM and in Tbx4LME-Cre Tsc2fl/fl mice did not harbor TSC2 mutations, our study demonstrates that constitutively active mTORC1 lung mesenchymal cells orchestrated dysfunctional EC responses that contributed to pulmonary vascular remodeling.


Assuntos
Linfangioleiomiomatose , Proteína 2 do Complexo Esclerose Tuberosa , Esclerose Tuberosa , Proteínas Supressoras de Tumor , Animais , Humanos , Lactente , Camundongos , Células Endoteliais/metabolismo , Pulmão/metabolismo , Linfangioleiomiomatose/genética , Linfangioleiomiomatose/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Mesoderma/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Remodelação Vascular/genética , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , Técnicas In Vitro
6.
Adv Mater ; 34(28): e2202992, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35522531

RESUMO

Epithelial cell organoids have increased opportunities to probe questions on tissue development and disease in vitro and for therapeutic cell transplantation. Despite their potential, current protocols to grow these organoids almost exclusively depend on culture within 3D Matrigel, which limits defined culture conditions, introduces animal components, and results in heterogenous organoids (i.e., shape, size, composition). Here, a method is described that relies on hyaluronic acid hydrogels for the generation and expansion of lung alveolar organoids (alveolospheres). Using synthetic hydrogels with defined chemical and physical properties, human-induced pluripotent stem cell (iPSC)-derived alveolar type 2 cells (iAT2s) self-assemble into alveolospheres and propagate in Matrigel-free conditions. By engineering predefined microcavities within these hydrogels, the heterogeneity of alveolosphere size and structure is reduced when compared to 3D culture, while maintaining the alveolar type 2 cell fate of human iAT2-derived progenitor cells. This hydrogel system is a facile and accessible system for the culture of iPSC-derived lung progenitors and the method can be expanded to the culture of primary mouse tissue derived AT2 and other epithelial progenitor and stem cell aggregates.


Assuntos
Hidrogéis , Células-Tronco Pluripotentes Induzidas , Animais , Humanos , Ácido Hialurônico/metabolismo , Hidrogéis/química , Células-Tronco Pluripotentes Induzidas/metabolismo , Pulmão , Camundongos , Organoides/metabolismo
7.
ACS Nano ; 16(3): 4666-4683, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35266686

RESUMO

A long-standing goal of nanomedicine is to improve a drug's benefit by loading it into a nanocarrier that homes solely to a specific target cell and organ. Unfortunately, nanocarriers usually end up with only a small percentage of the injected dose (% ID) in the target organ, due largely to clearance by the liver and spleen. Further, cell-type-specific targeting is rarely achieved without reducing target organ accumulation. To solve these problems, we introduce DART (dual affinity to RBCs and target cells), in which nanocarriers are conjugated to two affinity ligands, one binding red blood cells and one binding a target cell (here, pulmonary endothelial cells). DART nanocarriers first bind red blood cells and then transfer to the target organ's endothelial cells as the bound red blood cells squeeze through capillaries. We show that within minutes after intravascular injection in mice nearly 70% ID of DART nanocarriers accumulate in the target organ (lungs), more than doubling the % ID ceiling achieved by a multitude of prior technologies, finally achieving a majority % ID in a target organ. Humanized DART nanocarriers in ex vivo perfused human lungs recapitulate this phenomenon. Furthermore, DART enhances the selectivity of delivery to target endothelial cells over local phagocytes within the target organ by 6-fold. DART's marked improvement in both organ- and cell-type targeting may thus be helpful in localizing drugs for a multitude of medical applications.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas , Animais , Portadores de Fármacos/metabolismo , Células Endoteliais/metabolismo , Eritrócitos , Pulmão/metabolismo , Camundongos , Preparações Farmacêuticas
8.
Nat Nanotechnol ; 17(1): 86-97, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34795440

RESUMO

This study shows that the supramolecular arrangement of proteins in nanoparticle structures predicts nanoparticle accumulation in neutrophils in acute lung inflammation (ALI). We observed homing to inflamed lungs for a variety of nanoparticles with agglutinated protein (NAPs), defined by arrangement of protein in or on the nanoparticles via hydrophobic interactions, crosslinking and electrostatic interactions. Nanoparticles with symmetric protein arrangement (for example, viral capsids) had no selectivity for inflamed lungs. Flow cytometry and immunohistochemistry showed NAPs have tropism for pulmonary neutrophils. Protein-conjugated liposomes were engineered to recapitulate NAP tropism for pulmonary neutrophils. NAP uptake in neutrophils was shown to depend on complement opsonization. We demonstrate diagnostic imaging of ALI with NAPs; show NAP tropism for inflamed human donor lungs; and show that NAPs can remediate pulmonary oedema in ALI. This work demonstrates that structure-dependent tropism for neutrophils drives NAPs to inflamed lungs and shows NAPs can detect and treat ALI.


Assuntos
Inflamação/patologia , Pulmão/patologia , Nanopartículas/química , Neutrófilos/patologia , Proteínas/química , Doença Aguda , Aglutinação/efeitos dos fármacos , Animais , Anticorpos/farmacologia , Reagentes de Ligações Cruzadas/química , Dextranos/química , Humanos , Lipopolissacarídeos , Lipossomos , Pulmão/diagnóstico por imagem , Masculino , Camundongos Endogâmicos C57BL , Muramidase/metabolismo , Neutrófilos/efeitos dos fármacos , Proteínas Opsonizantes/metabolismo , Eletricidade Estática , Distribuição Tecidual/efeitos dos fármacos , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
9.
Adv Drug Deliv Rev ; 178: 113992, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34597748

RESUMO

Drug delivery research pursues many types of carriers including proteins and other macromolecules, natural and synthetic polymeric structures, nanocarriers of diverse compositions and cells. In particular, liposomes and lipid nanoparticles represent arguably the most advanced and popular human-made nanocarriers, already in multiple clinical applications. On the other hand, red blood cells (RBCs) represent attractive natural carriers for the vascular route, featuring at least two distinct compartments for loading pharmacological cargoes, namely inner space enclosed by the plasma membrane and the outer surface of this membrane. Historically, studies of liposomal drug delivery systems (DDS) astronomically outnumbered and surpassed the RBC-based DDS. Nevertheless, these two types of carriers have different profile of advantages and disadvantages. Recent studies showed that RBC-based drug carriers indeed may feature unique pharmacokinetic and biodistribution characteristics favorably changing benefit/risk ratio of some cargo agents. Furthermore, RBC carriage cardinally alters behavior and effect of nanocarriers in the bloodstream, so called RBC hitchhiking (RBC-HH). This article represents an attempt for the comparative analysis of liposomal vs RBC drug delivery, culminating with design of hybrid DDSs enabling mutual collaborative advantages such as RBC-HH and camouflaging nanoparticles by RBC membrane. Finally, we discuss the key current challenges faced by these and other RBC-based DDSs including the issue of potential unintended and adverse effect and contingency measures to ameliorate this and other concerns.


Assuntos
Eritrócitos/química , Nanopartículas/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Lipídeos/química , Lipossomos/química
10.
Adv Drug Deliv Rev ; 157: 96-117, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579890

RESUMO

The bloodstream is the main transporting pathway for drug delivery systems (DDS) from the site of administration to the intended site of action. In many cases, components of the vascular system represent therapeutic targets. Endothelial cells, which line the luminal surface of the vasculature, play a tripartite role of the key target, barrier, or victim of nanomedicines in the bloodstream. Circulating DDS may accumulate in the vascular areas of interest and in off-target areas via mechanisms bypassing specific molecular recognition, but using ligands of specific vascular determinant molecules enables a degree of precision, efficacy, and specificity of delivery unattainable by non-affinity DDS. Three decades of research efforts have focused on specific vascular targeting, which have yielded a multitude of DDS, many of which are currently undergoing a translational phase of development for biomedical applications, including interventions in the cardiovascular, pulmonary, and central nervous systems, regulation of endothelial functions, host defense, and permeation of vascular barriers. We discuss the design of endothelial-targeted nanocarriers, factors underlying their interactions with cells and tissues, and describe examples of their investigational use in models of acute vascular inflammation with an eye on translational challenges.


Assuntos
Sistemas de Liberação de Medicamentos , Endotélio Vascular/metabolismo , Doenças Vasculares/tratamento farmacológico , Animais , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Humanos , Inflamação/tratamento farmacológico , Nanomedicina , Nanopartículas
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