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1.
Nano Lett ; 22(17): 7220-7229, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35994713

RESUMO

The immune checkpoint blockade (ICB) faces a low response rate in clinical cancer treatment. Chemotherapy could enhance the response rate of the ICB, but patients would suffer from side effects. The off-target toxicity could be reduced by loading the chemotherapeutic agent through nanocarriers. Therefore, we developed a polymeric carrier for doxorubicin (DOX) loading to form DOX nanoparticles (DOX NPs), which were spatiotemporally responsive to the tumor microenvironment (TME). DOX NPs had an efficient transcytosis property for deep tumor infiltration and sustained drug release ability. Unfortunately, a binary therapy of DOX NPs and ICB induces tumor adaptive resistance and causes dynamic deterioration of the TME. We propose for the first time that TGF-ß1 is a major cause of tumor adaptive resistance and developed an immune cocktail therapy containing DOX NPs, ICB, and TGF-ß1 gene silencing nanoparticles. This therapy successfully overcame tumor adaptive resistance by reversing the immunosuppressive TME and achieved enhanced tumor treatment efficiency.


Assuntos
Nanopartículas , Neoplasias , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/farmacologia , Humanos , Imunoterapia , Nanopartículas/uso terapêutico , Transcitose , Fator de Crescimento Transformador beta1 , Microambiente Tumoral
2.
Nano Lett ; 22(17): 6877-6887, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36036792

RESUMO

Intracellular transcytosis can enhance the penetration of nanomedicines to deep avascular tumor tissues, but strategies that can improve transcytosis are limited. In this study, we discovered that pyknomorphic extracellular matrix (ECM) is a shield that impairs endocytosis of nanoparticles and their movement between adjacent cells and thus limits their active transcytosis in tumors. We further showed that degradation of pivotal constituent of ECM (i.e., collagen) effectively enhances intracellular transcytosis of nanoparticles. Specifically, a collagenase conjugating transcytosis nanoparticle (Col-TNP) can dissociate into collagenase and cationized gold nanoparticles in response to tumor acidity, which enables their ECM tampering ability and active transcytosis in tumors. The breakage of ECM further enhances the active transcytosis of cationized nanoparticles into deep tumor tissues as well as radiosensitization efficacy of pancreatic adenocarcinoma. Our study opens up new paths to enhance the active transcytosis of nanomedicines for the treatment of cancers and other diseases.


Assuntos
Adenocarcinoma , Nanopartículas Metálicas , Nanopartículas , Neoplasias Pancreáticas , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Colagenases/metabolismo , Matriz Extracelular/metabolismo , Ouro/metabolismo , Humanos , Nanopartículas Metálicas/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/radioterapia , Transcitose
3.
Biochem Biophys Res Commun ; 625: 128-133, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35961136

RESUMO

Various methods of generating 2D and 3D in vitro blood-brain barrier (BBB) models have previously been published with the objective of developing therapeutics for brain diseases. In general, published methods including our published method demonstrate that in vivo-like semi-permeable barrier can be generated. To further verify that an in vitro BBB model closely represents BBB, functional validation is required. Here, we functionally validate our in vitro 3D BBB model using rituximab as a representative therapeutic antibody and previously published anti-TfR (transferrin receptor) antibodies as representative BBB-penetrating antibodies. We demonstrate that our BBB model can efficiently block rituximab while allowing receptor-mediated transcytosis (RMT) of anti-TfR antibodies. In addition, we showed that RMT efficacy of anti-TfR antibodies with different binding affinity can be displayed using our BBB model. In conclusion, this demonstrates that our BBB model functionally mimics the BBB as well as having BBB-like physical properties, further establishing our BBB model as a screening tool for discovery and development of therapeutics for brain diseases.


Assuntos
Barreira Hematoencefálica , Encefalopatias , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Encefalopatias/metabolismo , Técnicas de Cocultura , Humanos , Receptores da Transferrina/metabolismo , Rituximab , Transcitose
4.
Metabolism ; 135: 155274, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35917895

RESUMO

BACKGROUND: Activation of NLRP3 inflammasome accelerates the formation of atherosclerotic plaques. Here, we evaluated the effects of inflammation on the expression of the NLRP3 inflammasome in endothelial cells (ECs). METHODS: The effect of TNF-α on transcytosis of LDL was measured. VCAM-1 binding peptide targeting cationic liposomes (PCLs) were prepared as siRNA vectors. Methylated NLRP3 siRNA was encapsulated into the PCLs to knock down NLRP3 in vitro and in vivo. In rats with partial carotid ligation, TNF-α-induced LDL retention in the carotid artery endothelium was observed. In ApoE-/- mice, NLRP3 siRNA-PCLs were injected intravenously to observe their effect on the formation of atherosclerosis. RESULTS: Our results showed that TNF-α upregulated NLRP3 in ECs, promoting the assembly of the NLRP3 inflammasome and processing of pro-IL-1ß into IL-1ß. Moreover, TNF-α accelerated LDL transcytosis in ECs. Knockdown of NLRP3 prevented TNF-α-induced NLPR3 inflammasome/IL-1ß signaling and LDL transcytosis. Using optimized cationic liposomes to encapsulate methylated NLRP3 siRNA, resulting in targeting of VCAM-1-expressing ECs, to knockdown NLRP3, TNF-α-induced NLRP3 inflammasome activation and LDL transcytosis were prevented. Using the partial carotid ligation as an atherosclerosis rat model, we found that local administration of NLRP3 siRNA-PCLs efficiently knocked down NLPR3 expression in the carotid endothelium and dramatically attenuated the deposition of atherogenic LDL in carotid ECs in TNF-α-challenged rats. Furthermore, NLRP3 siRNA-PCLs were injected intravenously in ApoE-/- mice, resulting in reduced plaque formation. CONCLUSION: These findings established a novel strategy for targeting the NLRP3 inflammasome using NLRP3 siRNA-PCLs to interrupt LDL transcytosis, representing a potential novel therapy for atherosclerosis.


Assuntos
Aterosclerose , Inflamassomos , Animais , Apolipoproteínas E/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/terapia , Células Endoteliais/metabolismo , Inflamassomos/metabolismo , Lipoproteínas LDL/metabolismo , Lipossomos , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Transcitose , Fator de Necrose Tumoral alfa , Molécula 1 de Adesão de Célula Vascular/genética
5.
J Control Release ; 349: 1031-1044, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35901858

RESUMO

Treatment of neurological lysosomal storage disorders (LSDs) are limited because of impermeability of the blood-brain barrier (BBB) to macromolecules. Nanoformulations targeting BBB transcytosis are being explored, but the status of these routes in LSDs is unknown. We studied nanocarriers (NCs) targeted to the transferrin receptor (TfR), ganglioside GM1 or ICAM1, associated to the clathrin, caveolar or cell adhesion molecule (CAM) routes, respectively. We used brain endothelial cells and mouse models of acid sphingomyelinase-deficient Niemann Pick disease (NPD), and postmortem LSD patients' brains, all compared to respective controls. NC transcytosis across brain endothelial cells and brain distribution in mice were affected, yet through different mechanisms. Reduced TfR and clathrin expression were found, along with decreased transcytosis in cells and mouse brain distribution. Caveolin-1 expression and GM1 transcytosis were also reduced, yet increased GM1 levels seemed to compensate, providing similar NC brain distribution in NPD vs. control mice. A tendency to lower NHE-1 levels was seen, but highly increased ICAM1 expression in cells and human brains correlated with increased transcytosis and brain distribution in mice. Thus, transcytosis-related alterations in NPD and likely other LSDs may impact therapeutic access to the brain, illustrating the need for these mechanistic studies.


Assuntos
Barreira Hematoencefálica , Doenças por Armazenamento dos Lisossomos , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Catecóis , Caveolina 1 , Clatrina/metabolismo , Células Endoteliais/metabolismo , Gangliosídeo G(M1)/metabolismo , Humanos , Dietilamida do Ácido Lisérgico/metabolismo , Doenças por Armazenamento dos Lisossomos/tratamento farmacológico , Doenças por Armazenamento dos Lisossomos/metabolismo , Camundongos , Compostos Organometálicos , Receptores da Transferrina/metabolismo , Esfingomielina Fosfodiesterase/metabolismo , Transcitose
6.
Adv Drug Deliv Rev ; 188: 114450, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35841955

RESUMO

Extracellular vesicles (EVs), including microparticles and exosomes, have emerged as potential tools for tumor targeting delivery during the past years. Recently, mass of strategies are applied to assist EVs to accumulate and penetrate into deep tumor sites. In this review, EVs from different cells with unique innate characters and engineered approaches (e.g. chemical engineering, genetical engineering and biomimetic engineering) as drug delivery systems to enhance tumor accumulation and penetration are summarized. Meanwhile, efficient biological function modulation (e.g. extracellular matrix degradation, mechanical property regulation and transcytosis) is introduced to facilitate tumor accumulation and penetration of EVs. Finally, the prospects and challenges on further clinical applications of EVs are discussed.


Assuntos
Exossomos , Vesículas Extracelulares , Neoplasias , Sistemas de Liberação de Medicamentos , Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Transcitose
7.
Fluids Barriers CNS ; 19(1): 57, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35820896

RESUMO

BACKGROUND: Traumatic brain injury (TBI) provokes secondary pathological damage, such as damage to the blood-brain barrier (BBB), ischaemia and inflammation. Major facilitator superfamily domain-containing 2a (Mfsd2a) has been demonstrated to be critical in limiting the increase in BBB vesicle transcytosis following brain injury. Recent studies suggest that a novel and selective modulator of the sphingosine-1-phosphate receptor 1 (S1P1), CYM-5442, maintains the integrity of the BBB by restricting vesicle transcytosis during acute ischaemic stroke. In the current study, we investigated whether CYM-5442, evaluated in a short-term study, could protect the brains of mice with acute-stage TBI by reversing the increase in vesicle transport due to reduced Mfsd2a expression after TBI. METHODS: We used the well-characterized model of TBI caused by controlled cortical impact. CYM-5442 (0.3, 1, 3 mg/kg) was intraperitoneally injected 30 min after surgery for 7 consecutive days. To investigate the effect of CYM-5442 on vesicle transcytosis, we downregulated and upregulated Mfsd2a expression using a specific AAV prior to evaluation of the TBI model. MRI scanning, cerebral blood flow, circulating blood counts, ELISA, TEM, WB, and immunostaining evaluations were performed after brain injury. RESULTS: CYM-5442 significantly attenuated neurological deficits and reduced brain oedema in TBI mice. CYM-5442 transiently suppressed lymphocyte trafficking but did not induce persistent lymphocytopenia. After TBI, the levels of Mfsd2a were decreased significantly, while the levels of CAV-1 and albumin were increased. In addition, Mfsd2a deficiency caused inadequate sphingosine-1-phosphate (S1P) transport in the brain parenchyma, and the regulation of BBB permeability by Mfsd2a after TBI was shown to be related to changes in vesicle transcytosis. Downregulation of Mfsd2a in mice markedly increased the BBB permeability, neurological deficit scores, and brain water contents after TBI. Intervention with CYM-5442 after TBI protected the BBB by significantly reducing the vesicle transcytosis of cerebrovascular endothelial cells. CONCLUSION: In addition to transiently suppressing lymphocytes, CYM-5442 alleviated the neurological deficits, cerebral edema and protective BBB permeability in TBI mice by reducing the vesicle transcytosis of cerebrovascular endothelial cells.


Assuntos
Barreira Hematoencefálica , Lesões Encefálicas Traumáticas , Receptores de Esfingosina-1-Fosfato , Acidente Vascular Cerebral , Animais , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/patologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Camundongos , Receptores de Esfingosina-1-Fosfato/metabolismo , Acidente Vascular Cerebral/metabolismo , Transcitose
8.
Fluids Barriers CNS ; 19(1): 60, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35879759

RESUMO

Extracellular vesicles (EVs) are particles naturally released from cells that are delimited by a lipid bilayer and are unable to replicate. How the EVs cross the Blood-Brain barrier (BBB) in a bidirectional manner between the bloodstream and brain parenchyma remains poorly understood. Most in vitro models that have evaluated this event have relied on monolayer transwell or microfluidic organ-on-a-chip techniques that do not account for the combined effect of all cellular layers that constitute the BBB at different sites of the Central Nervous System. There has not been direct transcytosis visualization through the BBB in mammals in vivo, and evidence comes from in vivo experiments in zebrafish. Literature is scarce on this topic, and techniques describing the mechanisms of EVs motion through the BBB are inconsistent. This review will focus on in vitro and in vivo methodologies used to evaluate EVs transcytosis, how EVs overcome this fundamental structure, and discuss potential methodological approaches for future analyses to clarify these issues. Understanding how EVs cross the BBB will be essential for their future use as vehicles in pharmacology and therapeutics.


Assuntos
Barreira Hematoencefálica , Vesículas Extracelulares , Animais , Transporte Biológico , Vesículas Extracelulares/metabolismo , Mamíferos , Transcitose , Peixe-Zebra
9.
J Vis Exp ; (184)2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35758707

RESUMO

Dysfunction of the blood-retinal barrier (BRB) contributes to the pathophysiology of several vascular eye diseases, often resulting in retinal edema and subsequent vision loss. The inner blood-retinal barrier (iBRB) is mainly composed of retinal vascular endothelium with low permeability under physiological conditions. This feature of low permeability is tightly regulated and maintained by low rates of paracellular transport between adjacent retinal microvascular endothelial cells, as well as transcellular transport (transcytosis) through them. The assessment of retinal transcellular barrier permeability may provide fundamental insights into iBRB integrity in health and disease. In this study, we describe an endothelial cell (EC) transcytosis assay, as an in vitro model for evaluating iBRB permeability, using human retinal microvascular endothelial cells (HRMECs). This assay assesses the ability of HRMECs to transport transferrin and horseradish peroxidase (HRP) in receptor- and caveolae-mediated transcellular transport processes, respectively. Fully confluent HRMECs cultured on porous membrane were incubated with fluorescent-tagged transferrin (clathrin-dependent transcytosis) or HRP (caveolae-mediated transcytosis) to measure the levels of transferrin or HRP transferred to the bottom chamber, indicative of transcytosis levels across the EC monolayer. Wnt signaling, a known pathway regulating iBRB, was modulated to demonstrate the caveolae-mediated HRP-based transcytosis assay method. The EC transcytosis assay described here may provide a useful tool for investigating the molecular regulators of EC permeability and iBRB integrity in vascular pathologies and for screening drug delivery systems.


Assuntos
Barreira Hematorretiniana , Células Endoteliais , Células Endoteliais/metabolismo , Humanos , Permeabilidade , Transcitose , Transferrinas/metabolismo
10.
Adv Sci (Weinh) ; 9(21): e2201414, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35652273

RESUMO

Bile acid-modified nanoparticles provide a convenient strategy to improve oral bioavailability of poorly permeable drugs by exploiting specific interactions with bile acid transporters. However, the underlying mechanisms are unknown, especially considering the different absorption sites of free bile acids (ileum) and digested fat molecules from bile acid-emulsified fat droplets (duodenum). Here, glycocholic acid (GCA)-conjugated polystyrene nanoparticles (GCPNs) are synthesized and their transport in Caco-2 cell models is studied. GCA conjugation enhances the uptake by interactions with apical sodium-dependent bile acid transporter (ASBT). A new pathway correlated with both ASBT and chylomicron pathways is identified. Meanwhile, the higher uptake of GCPNs does not lead to higher transcytosis to the same degree compared with unmodified nanoparticles (CPNs). The pharmacological and genomics study confirm that GCA conjugation changes the endocytosis mechanisms and downregulates the cellular response to the transport at gene levels, which works as a negative feedback loop and explains the higher cellular retention of GCPNs. These findings offer a solid foundation in the bile acid-based nanomedicine design, with utilizing advantages of the ASBT-mediated uptake, as well as inspiration to take comprehensive consideration of the cellular response with more developed technologies.


Assuntos
Quilomícrons , Nanopartículas , Ácidos e Sais Biliares , Células CACO-2 , Retroalimentação , Humanos , Transcitose
11.
Sci Rep ; 12(1): 9474, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35676405

RESUMO

Removal of particulate materials that would otherwise cumulate within the airspace and hinder the gas exchange is one of the central processes of maintaining lung homeostasis. While the importance of the particle uptake by alveolar macrophages and their expulsion via the airways mucociliary escalator is well established, very little is known about the alternative route for removing the particles via direct crossing the lung epithelium for transfer into the pulmonary lymph and bloodstream. This study dissected sequential mechanisms involved in nanoparticle transcytosis through the alveolar epithelial cell layer. By a combination of live cell, super resolution, and electron microscopy and RNA interference study, we have dissected temporal steps of nanoparticle transcytosis through alveolar epithelium. Our study revealed that caveolin is essential for the firm adhesion of the silica nanoparticle agglomerates to the apical membrane and their subsequent rapid internalization with the help of macropinocytic elements C-terminal-binding protein1 and Rabankyrin-5 but not dynamin. Actin, but not microtubules, played a major role in nanoparticle uptake and subsequent transportation. The compartments with nanoparticles were tethered to trans-Golgi network to be jointly transported along actin stress fibers across the cytoplasm, employing a myosin-dependent mechanism. The trans-Golgi nanoparticle transport machinery was positive to Rab6A, a marker linked to vesicle exocytosis. Exocytosis was primarily occurring at the basolateral plane of the alveolar epithelial cells. The high-proficiency novel caveolin and Rabankyrin-5 associated uptake and transcellular transport of nanoparticles across the AEC barrier supports its importance in clearance of amorphous silica and other types of non-inflammatory nanoparticles that are rapidly removed from the lungs following their inhalation.


Assuntos
Nanopartículas , Dióxido de Silício , Actinas/metabolismo , Caveolina 1/metabolismo , Nanopartículas/metabolismo , Dióxido de Silício/metabolismo , Transcitose
12.
Nanoscale ; 14(23): 8510-8524, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35660835

RESUMO

The poor penetration of nanomaterials in solid tumours and difficulty in monitoring their penetration depth are major obstacles in their application for the treatment of solid tumours. Herein, pH-responsive carbon dots (ZCD) based on a zeolitic imidazolate framework (ZIF-8) were fabricated to achieve the deep delivery of the chemotherapeutic doxorubicin (DOX) via a hierarchical size/charge dual-transformation and transcytosis. The as-prepared ZCD accumulated in the solid tumour and the acidic tumour microenvironment further triggered its decomposition. Firstly, ZCD was decomposed by the weakly acidic extracellular microenvironment of the solid tumour, enabling it to transform into small and neutrally charged particles. Subsequently, these particles were endocytosed by lysosomes, and further disintegrated into smaller and positively charged particles, which could target the Golgi apparatus. Consequently, ZCD delivered DOX deep into the solid tumour via a size-shrinking strategy and Golgi-mediated transcytosis, thus significantly improving its antitumour efficacy. In addition, carbonization endowed ZCD with superior fluorescence property, which was enhanced in the acidic microenvironment, thus improving the sensitivity and accuracy of ex vivo monitoring of the penetration depth of the nanomedicine in real time. Collectively, our results confirmed that the carbon dots obtained via the direct carbonization of ZIF-8 simultaneously exhibited enhanced deep penetration into solid tumours and fluorescence, which could be monitored, and that the carbonization of functional materials is effective to enhance their fluorescence, and further broaden their applications.


Assuntos
Nanopartículas , Neoplasias , Zeolitas , Carbono , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Complexo de Golgi/patologia , Humanos , Concentração de Íons de Hidrogênio , Lisossomos/patologia , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Transcitose , Microambiente Tumoral , Zeolitas/uso terapêutico
13.
Neuron ; 110(10): 1601-1603, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35588710

RESUMO

How is the brain so efficient at excluding proteins, drugs, and immune cells from the blood? In this issue of Neuron, Ayloo et al. (2022) find that an extracellular matrix protein secreted by CNS pericytes shuts down endocytic transport in blood brain barrier endothelial cells.


Assuntos
Barreira Hematoencefálica , Pericitos , Transporte Biológico , Barreira Hematoencefálica/metabolismo , Encéfalo , Células Endoteliais/metabolismo , Pericitos/metabolismo , Transcitose/fisiologia
14.
J Cell Biol ; 221(7)2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35579602

RESUMO

Neuregulins (NRGs) are EGF-like ligands associated with cognitive disorders. Unprocessed proNRG3 is cleaved by BACE1 to generate the mature membrane-bound NRG3 ligand, but the subcellular site of proNRG3 cleavage, mechanisms underlying its transport into axons, and presynaptic accumulation remain unknown. Using an optogenetic proNRG3 cleavage reporter (LA143-NRG3), we investigate the spatial-temporal dynamics of NRG3 processing and sorting in neurons. In dark conditions, unprocessed LA143-NRG3 is retained in the trans-Golgi network but, upon photoactivation, is cleaved by BACE1 and released from the TGN. Mature NRG3 then emerges on the somatodendritic plasma membrane from where it is re-endocytosed and anterogradely transported on Rab4+ vesicles into axons via transcytosis. By contrast, the BACE1 substrate APP is sorted into axons on Rab11+ vesicles. Lastly, by a mechanism we denote "trans-synaptic retention," NRG3 accumulates at presynaptic terminals by stable interaction with its receptor ErbB4 on postsynaptic GABAergic interneurons. We propose that trans-synaptic retention may account for polarized expression of other neuronal transmembrane ligands and receptors.


Assuntos
Axônios , Neurregulinas , Receptor ErbB-4 , Transcitose , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Axônios/metabolismo , Células HEK293 , Humanos , Ligantes , Camundongos , Neurregulinas/genética , Neurregulinas/metabolismo , Ratos , Receptor ErbB-4/genética , Receptor ErbB-4/metabolismo
15.
Infect Immun ; 90(6): e0004122, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35579465

RESUMO

Secretory IgA (SIgA) is the most abundant antibody type in intestinal secretions where it contributes to safeguarding the epithelium from invasive pathogens like the Gram-negative bacterium, Salmonella enterica serovar Typhimurium (STm). For example, we recently reported that passive oral administration of the recombinant monoclonal SIgA antibody, Sal4, to mice promotes STm agglutination in the intestinal lumen and restricts bacterial invasion of Peyer's patch tissues. In this report, we sought to recapitulate Sal4-mediated protection against STm in human Enteroids and human intestinal organoids (HIOs) as models to decipher the molecular mechanisms by which antibodies function in mucosal immunity in the human gastrointestinal tract. We confirm that Enteroids and HIO-derived monolayers are permissive to STm infection, dependent on HilD, the master transcriptional regulator of the SPI-I type three secretion system (T3SS). Stimulation of M-like cells in both Enteroids and HIOs by the addition of RANKL further enhanced STm invasion. The apical addition of Sal4 mouse IgA, as well as recombinant human Sal4 dimeric IgA (dIgA) and SIgA resulted a dose-dependent reduction in bacterial invasion. Moreover, basolateral application of Sal4 dIgA to Enteroid and HIO monolayers gave rise to SIgA in the apical compartment via a pathway dependent on expression of the polymeric immunoglobulin receptor (pIgR). The resulting Sal4 SIgA was sufficient to reduce STm invasion of Enteroid and HIO epithelial cell monolayers by ~20-fold. Recombinant Sal4 IgG was also transported in the Enteroid and HIOs, but to a lesser degree and via a pathway dependent on the neonatal Fc receptor (FCGRT). The models described lay the foundation for future studies into detailed mechanisms of IgA and IgG protection against STm and other pathogens.


Assuntos
Imunoglobulina A , Organoides , Animais , Humanos , Imunoglobulina A/metabolismo , Imunoglobulina A Secretora , Imunoglobulina G/metabolismo , Mucosa Intestinal/metabolismo , Camundongos , Organoides/metabolismo , Salmonella typhimurium , Transcitose
16.
Pharm Res ; 39(7): 1457-1468, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35578062

RESUMO

Treatment of brain disorders relies on efficient delivery of therapeutics to the brain, which is hindered by the blood-brain barrier (BBB). The work of Prof. Margareta Hammarlund-Udenaes was instrumental in understanding the principles of drug delivery to the brain and developing new tools to study it. Here, we show how some of the concepts developed in her research can be translated to in vivo 2-photon microscopy (2PM) studies of the BBB. We primarily focus on the methods developed in our laboratory to characterize the paracellular diffusion, adsorptive-mediated transcytosis, and receptor-mediated transcytosis of drug nanocarriers at the microscale, illustrating how 2PM can deepen our understanding of the mechanisms of drug delivery to the brain.


Assuntos
Barreira Hematoencefálica , Microscopia , Transporte Biológico , Encéfalo , Feminino , Humanos , Transcitose
17.
Fluids Barriers CNS ; 19(1): 37, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35637478

RESUMO

Parkinson's disease is mainly caused by aggregation of α-synuclein (α-syn) in the brain. Exchange of α-syn between the brain and peripheral tissues could have important pathophysiological and therapeutic implications, but the trafficking mechanism of α-syn across the blood brain-barrier (BBB) remains unclear. In this study, we therefore investigated uptake and transport mechanisms of α-syn monomers and oligomers across an in vitro BBB model system. Both α-syn monomers and oligomers were internalized by primary brain endothelial cells, with increased restriction of oligomeric over monomeric transport. To enlighten the trafficking route of monomeric α-syn in brain endothelial cells, we investigated co-localization of α-syn and intracellular markers of vesicular transport. Here, we observed the highest colocalization with clathrin, Rab7 and VPS35, suggesting a clathrin-dependent internalization, preferentially followed by a late endosome retromer-connected trafficking pathway. Furthermore, STED microscopy revealed monomeric α-syn trafficking via Rab7-decorated carriers. Knockdown of Caveolin1, VPS35, and Rab7 using siRNA did not affect monomeric α-syn uptake into endothelial cells. However, it significantly reduced transcytosis of monomeric α-syn in the luminal-abluminal direction, suggesting a polarized regulation of monomeric α-syn vesicular transport. Our findings suggest a direct role for Rab7 in polarized trafficking of monomeric α-syn across BBB endothelium, and the potential of Rab7 directed trafficking to constitute a target pathway for new therapeutic strategies against Parkinson's disease and related synucleinopathies.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Encéfalo/metabolismo , Clatrina/metabolismo , Células Endoteliais/metabolismo , Endotélio/metabolismo , Humanos , Doença de Parkinson/metabolismo , Transcitose , Proteínas de Transporte Vesicular , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , proteínas de unión al GTP Rab7
18.
Oxid Med Cell Longev ; 2022: 2253478, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464770

RESUMO

The recently described phenomenon of cholesterol-loaded low-density lipoproteins (LDL) entering the arterial wall from the lumen by transcytosis has been accepted as an alternative for the long-held concept that atherogenesis involves only passive LDL movement across an injured or dysfunctional endothelial barrier. This active transport of LDL can now adequately explain why plaques (atheromas) appear under an intact, uninjured endothelium. However, the LDL transcytosis hypothesis is still questionable, mainly because the process serves no clear physiological purpose. Moreover, central components of the putative LDL transcytosis apparatus are shared by the counter process of cholesterol efflux and reverse cholesterol transport (RCT) and therefore can essentially create an energy-wasting futile cycle and paradoxically be pro- and antiatherogenic simultaneously. Hence, by critically reviewing the literature, we wish to put forward an alternative interpretation that, in our opinion, better fits the experimental evidence. We assert that most of the accumulating cholesterol (mainly as LDL) reaches the intima not from the lumen by transcytosis, but from the artery's inner layers: the adventitia and media. We have named this directional cholesterol transport transmural cholesterol flux (TCF). We suggest that excess cholesterol, diffusing from the avascular (i.e., devoid of blood and lymph vessels) media's smooth muscle cells, is cleared by the endothelium through its apical membrane. A plaque is formed when this cholesterol clearance rate lags behind its rate of arrival by TCF.


Assuntos
Aterosclerose , Placa Aterosclerótica , Aorta/metabolismo , Colesterol , LDL-Colesterol , Humanos , Lipoproteínas LDL/metabolismo , Transcitose
19.
J Transl Med ; 20(1): 185, 2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35468852

RESUMO

BACKGROUND: Microlbuminuria is the earliest clinical evidence of diabetic kidney disease (DKD) and contributes to the induction and/or progression of DKD. Previous studies have shown that increased expression of angiopoietin2 (ANGPT2) is correlated with an increase in albuminuria. However, the critical role of ANGPT2 in albuminuria development remains unclear. Some studies have shown the significance of transcytosis in the occurrence of albuminuria, but it is unknown whether it takes place in albumin recycling in renal tubular cells of patients with DKD. Furthermore, the potential mechanism of this association also remains unclear. METHODS: In this study, human renal tubular epithelial cells (HK-2) were cultured with high glucose in a Transwell plate to establish a transcytosis model, while C57BL/6 mice were intraperitoneally injected with streptozotocin to establish a DKD model. The expression of ANGPT2 and caveolin1 (CAV1) phosphorylation was dectected through immunohistochemistry and western blot analysis. RESULTS: Transcytosis of albumin in renal tubular epithelial cells was downregulated after high glucose exposure, and increased expression of ANGPT2 and CAV1 phosphorylation both in vivo and in vitro was observed. Inhibition of ANGPT2 and CAV1 independently promoted transcytosis. Furthermore, ANGPT2 downregulation inhibited CAV1 phosphorylation, whereas CAV1 phosphorylation had no effect on the expression of ANGPT2. CONCLUSIONS: ANGPT2 reduces albumin transcytosis across renal tubular epithelial cells under high glucose conditions by activating CAV1 phosphorylation, thus increasing albuminuria in DKD. These findings suggested that ANGPT2 and CAV1 may be promising therapeutic targets for albuminuria in DKD.


Assuntos
Albuminúria , Transcitose , Albuminas/metabolismo , Albuminúria/complicações , Animais , Células Epiteliais/metabolismo , Feminino , Glucose/metabolismo , Glucose/toxicidade , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação
20.
Drug Metab Dispos ; 50(7): 909-922, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35489778

RESUMO

The multidrug resistance protein 1 (MDR1) P-glycoprotein (P-gp) is a clinically important transporter. In vitro P-gp inhibition assays have been routinely conducted to predict the potential for clinical drug-drug interactions (DDIs) mediated by P-gp. However, high interlaboratory and intersystem variability of P-gp IC50 data limits accurate prediction of DDIs using static models and decision criteria recommended by regulatory agencies. In this study, we calibrated two in vitro P-gp inhibition models: vesicular uptake of N-methyl-quinidine (NMQ) in MDR1 vesicles and bidirectional transport (BDT) of digoxin in Lilly Laboratories Cell Porcine Kidney 1 cells overexpressing MDR1 (LLC-MDR1) using a total of 48 P-gp inhibitor and noninhibitor drugs and digoxin DDI data from 70 clinical studies. Refined thresholds were derived using receiver operating characteristic analysis, and their predictive performance was compared with the decision frameworks proposed by regulatory agencies and selected reference. Furthermore, the impact of various IC50 calculation methods and nonspecific binding of drugs on DDI prediction was evaluated. Our studies suggest that the concentration of inhibitor based on highest approved dose dissolved in 250 ml divided by IC50(I2/IC50) is sufficient to predict P-gp related intestinal DDIs. IC50 obtained from vesicular inhibition assay with a refined threshold of I2/IC50 ≥ 25.9 provides comparable predictive power over those measured by net secretory flux and efflux ratio in LLC-MDR1 cells. We therefore recommend vesicular P-gp inhibition as our preferred method given its simplicity, lower variability, higher assay throughput, and more direct estimation of in vitro kinetic parameters, rather than BDT assay. SIGNIFICANCE STATEMENT: This study has conducted comprehensive calibration of two in vitro P-gp inhibition models: uptake in MDR1 vesicles and bidirectional transport in LLC-MDR1 cell monolayers to predict DDIs. This study suggests that IC50s obtained from vesicular inhibition with a refined threshold of I2/IC50 ≥ 25.9 provide comparable predictive power over those in LLC-MDR1 cells. Therefore, vesicular P-gp inhibition is recommended as the preferred method given its simplicity, lower variability, higher assay throughput, and more direct estimation of in vitro kinetic parameters.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Digoxina , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Transporte Biológico/fisiologia , Digoxina/metabolismo , Suínos , Transcitose
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