scholarly journals An Elvitegravir Nanoformulation Crosses the Blood–Brain Barrier and Suppresses HIV-1 Replication in Microglia

Viruses ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 564 ◽  
Author(s):  
Yuqing Gong ◽  
Kaining Zhi ◽  
Prashanth K. B. Nagesh ◽  
Namita Sinha ◽  
Pallabita Chowdhury ◽  
...  
Keyword(s):  
Viral Load ◽  
Subcellular Localization ◽  
Blood Brain Barrier ◽  
Viral Suppression ◽  
Human Monocyte ◽  
Brain Barrier ◽  
Blood Brain ◽  
In Vitro Bbb Model ◽  
Hiv 1

Even with an efficient combination of antiretroviral therapy (ART), which significantly decreases viral load in human immunodeficiency virus type 1 (HIV-1)-positive individuals, the occurrence of HIV-1-associated neurocognitive disorders (HAND) still exists. Microglia have been shown to have a significant role in HIV-1 replication in the brain and in subsequent HAND pathogenesis. However, due to the limited ability of ART drugs to cross the blood–brain barrier (BBB) after systemic administration, in addition to efflux transporter expression on microglia, the efficacy of ART drugs for viral suppression in microglia is suboptimal. Previously, we developed novel poly (lactic-co-glycolic acid) (PLGA)-based elvitegravir nanoparticles (PLGA-EVG NPs), which showed improved BBB penetration in vitro and improved viral suppression in HIV-1-infected primary macrophages, after crossing an in vitro BBB model. Our objective in the current study was to evaluate the efficacy of our PLGA-EVG NPs in an important central nervous system (CNS) HIV-1 reservoir, i.e., microglia. In this study, we evaluated the cyto-compatibility of the PLGA-EVG NPs in microglia, using an XTT (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) assay and cellular morphology observation. We also studied the endocytosis pathway and the subcellular localization of PLGA NPs in microglia, using various endocytosis inhibitors and subcellular localization markers. We determined the ability of PLGA-EVG NPs to suppress HIV-1 replication in microglia, after crossing an in vitro BBB model. We also studied the drug levels in mouse plasma and brain tissue, using immunodeficient NOD scid gamma (NSG) mice, and performed a pilot study, to evaluate the efficacy of PLGA-EVG NPs on viral suppression in the CNS, using an HIV-1 encephalitic (HIVE) mouse model. From our results, the PLGA-EVG NPs showed ~100% biocompatibility with microglia, as compared to control cells. The internalization of PLGA NPs in microglia occurred through caveolae-/clathrin-mediated endocytosis. PLGA NPs can also escape from endo-lysosomal compartments and deliver the therapeutics to cells efficiently. More importantly, the PLGA-EVG NPs were able to show ~25% more viral suppression in HIV-1-infected human-monocyte-derived microglia-like cells after crossing the in vitro BBB compared to the EVG native drug, without altering BBB integrity. PLGA-EVG NPs also showed a ~two-fold higher level in mouse brain and a trend of decreasing CNS HIV-1 viral load in HIV-1-infected mice. Overall, these results help us to create a safe and efficient drug delivery method to target HIV-1 reservoirs in the CNS, for potential clinical use.

Refining In Vitro Neurotoxicity Testing — The Development of Blood–Brain Barrier Models

2003 ◽  
Vol 31 (3) ◽  
pp. 273-276 ◽  
Author(s):  
Hanna Tähti ◽  
Heidi Nevala ◽  
Tarja Toimela
Keyword(s):  
Blood Brain Barrier ◽  
Cell Lines ◽  
Three Dimensional ◽  
Brain Barrier ◽  
Culture Methods ◽  
Blood Brain ◽  
Capillary Endothelial Cells ◽  
In Vitro Bbb Model

The purpose of this paper is to review the current state of development of advanced in vitro blood–brain barrier (BBB) models. The BBB is a special capillary bed that separates the blood from the central nervous system (CNS) parenchyma. Astrocytes maintain the integrity of the BBB, and, without astrocytic contacts, isolated brain capillary endothelial cells in culture lose their barrier characteristics. Therefore, when developing in vitro BBB models, it is important to add astrocytic factors into the culture system. Recently, novel filter techniques and co-culture methods have made it possible to develop models which resemble the in vivo functions of the BBB in an effective way. With a BBB model, kinetic factors can be added into the in vitro batteries used for evaluating the neurotoxic potential of chemicals. The in vitro BBB model also represents a useful tool for the in vitro prediction of the BBB permeability of drugs, and offers the possibility to scan a large number of drugs for their potential to enter the CNS. Cultured monolayers of brain endothelial cell lines or selected epithelial cell lines, combined with astrocyte and neuron cultures, form a novel three-dimensional technique for the screening of neurotoxic compounds.

scholarly journals VLA-4 mediated adhesion of melanoma cells on the blood–brain barrier is the critical cue for melanoma cell intercalation and barrier disruption

2018 ◽  
Vol 39 (10) ◽  
pp. 1995-2010 ◽  
Author(s):  
Ana B García-Martín ◽  
Pascale Zwicky ◽  
Thomas Gruber ◽  
Christoph Matti ◽  
Federica Moalli ◽  
...  
Keyword(s):  
Brain Metastasis ◽  
Blood Brain Barrier ◽  
Barrier Properties ◽  
Melanoma Cells ◽  
Brain Barrier ◽  
Adhesive Interaction ◽  
Inflammatory Conditions ◽  
Blood Brain ◽  
In Vitro Bbb Model

Melanoma is the most aggressive skin cancer in humans. One severe complication is the formation of brain metastasis, which requires extravasation of melanoma cells across the tight blood–brain barrier (BBB). Previously, VLA-4 has been assigned a role for the adhesive interaction of melanoma cells with non-BBB endothelial cells. However, the role of melanoma VLA-4 for breaching the BBB remained unknown. In this study, we used a mouse in vitro BBB model and imaged the shear resistant arrest of melanoma cells on the BBB. Similar to effector T cells, inflammatory conditions of the BBB increased the arrest of melanoma cells followed by a unique post-arrest behavior lacking immediate crawling. However, over time, melanoma cells intercalated into the BBB and compromised its barrier properties. Most importantly, antibody ablation of VLA-4 abrogated melanoma shear resistant arrest on and intercalation into the BBB and protected the BBB from barrier breakdown. A tissue microarray established from human brain metastasis revealed that indeed a majority of 92% of all human melanoma brain metastases stained VLA-4 positive. We propose VLA-4 as a target for the inhibition of brain metastasis formation in the context of personalized medicine identifying metastasizing VLA-4 positive melanoma.

scholarly journals GRL-04810 and GRL-05010, Difluoride-Containing Nonpeptidic HIV-1 Protease Inhibitors (PIs) That Inhibit the Replication of Multi-PI-Resistant HIV-1In Vitroand Possess Favorable Lipophilicity That May Allow Blood-Brain Barrier Penetration

2013 ◽  
Vol 57 (12) ◽  
pp. 6110-6121 ◽  
Author(s):  
Pedro Miguel Salcedo Gómez ◽  
Masayuki Amano ◽  
Sofiya Yashchuk ◽  
Akira Mizuno ◽  
Debananda Das ◽  
...  
Keyword(s):  
Protease Inhibitors ◽  
Blood Brain Barrier ◽  
Wide Spectrum ◽  
Laboratory Strain ◽  
Cyclic Ether ◽  
Brain Barrier ◽  
Blood Brain ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACTWe designed, synthesized, and identified two novel nonpeptidic human immunodeficiency virus type 1 (HIV-1) protease inhibitors (PIs), GRL-04810 and GRL-05010, containing the structure-based designed privileged cyclic ether-derived nonpeptide P2 ligand,bis-tetrahydrofuranylurethane (bis-THF), and a difluoride moiety, both of which are active against the laboratory strain HIV-1LAI(50% effective concentrations [EC50s], 0.0008 and 0.003 μM, respectively) with minimal cytotoxicity (50% cytotoxic concentrations [CC50s], 17.5 and 37.0 μM, respectively, in CD4+MT-2 cells). The two compounds were active against multi-PI-resistant clinical HIV-1 variants isolated from patients who had no response to various antiviral regimens. GRL-04810 and GRL-05010 also blocked the infectivity and replication of each of the HIV-1NL4-3variants selected by up to 5 μM lopinavir (EC50s, 0.03 and 0.03 μM, respectively) and atazanavir (EC50s, 0.02 and 0.04 μM, respectively). Moreover, they were active against darunavir (DRV)-resistant variants (EC50in 0.03 to 0.034 μM range for GRL-04810 and 0.026 to 0.043 μM for GRL-05010), while DRV had EC50s between 0.02 and 0.174 μM. GRL-04810 had a favorable lipophilicity profile as determined with the partition (logP) and distribution (logD) coefficients of −0.14 and −0.29, respectively. Thein vitroblood-brain barrier (BBB) permeability assay revealed that GRL-04810 and GRL-05010 may have a greater advantage in terms of crossing the BBB than the currently available PIs, with apparent penetration indexes of 47.8 × 10−6and 61.8 × 10−6cm/s, respectively. The present data demonstrate that GRL-04810 and GRL-05010 exert efficient activity against a wide spectrum of HIV-1 variantsin vitroand suggest that two fluorine atoms added to theirbis-THF moieties may well enhance their penetration across the BBB.

Interferon-β stabilizes barrier characteristics of the blood–brain barrier in four different species in vitro

2008 ◽  
Vol 14 (6) ◽  
pp. 843-852 ◽  
Author(s):  
J Kraus ◽  
K Voigt ◽  
AM Schuller ◽  
M Scholz ◽  
KS Kim ◽  
...  
Keyword(s):  
Blood Brain Barrier ◽  
Treatment Efficacy ◽  
Paracellular Permeability ◽  
Brain Barrier ◽  
Early Event ◽  
Interferon Β ◽  
Recombinant Interferon ◽  
Blood Brain ◽  
In Vitro Bbb Model

Background Blood–brain barrier (BBB) breakdown is an early event in the pathogenesis of multiple sclerosis (MS). In a previous study we have found a direct stabilization of barrier characteristics after treatment of bovine brain capillary endothelial cells (BCECs) with human recombinant interferon-β-1a (IFN-β-1a) in an in vitro BBB model. In the present study we examined the effect of human recombinant IFN-β-1a on the barrier properties of BCECs derived from four different species including humans to predict treatment efficacy of IFN-β-1a in MS patients. Methods We used primary bovine and porcine BCECs, as well as human and murine BCEC cell lines. We investigated the influence of human recombinant IFN-β-1a on the paracellular permeability for 3H-inulin and 14C-sucrose across monolayers of bovine, human, and murine BCECs. In addition, the transendothelial electrical resistance (TEER) was determined in in vitro systems applying porcine and murine BCECS. Results We found a stabilizing effect on the barrier characteristics of BCECs after pretreatment with IFN-β-1a in all applied in vitro models: addition of IFN-β-1a resulted in a significant decrease of the paracellular permeability across monolayers of human, bovine, and murine BCECs. Furthermore, the TEER was significantly increased after pretreatment of porcine and murine BCECs with IFN-β-1a. Conclusion Our data suggest that BBB stabilization by IFN-β-1a may contribute to its beneficial effects in the treatment of MS. A human in vitro BBB model might be useful as bioassay for testing the treatment efficacy of drugs in MS.

scholarly journals ALCAM (CD166) is involved in extravasation of monocytes rather than T cells across the blood–brain barrier

2016 ◽  
Vol 37 (8) ◽  
pp. 2894-2909 ◽  
Author(s):  
Ruth Lyck ◽  
Marc-André Lécuyer ◽  
Michael Abadier ◽  
Christof B Wyss ◽  
Christoph Matti ◽  
...  
Keyword(s):  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Th1 Cells ◽  
Human Brain Tissue ◽  
Autoimmune Encephalomyelitis ◽  
Tissue Samples ◽  
Blood Brain ◽  
Static Conditions ◽  
In Vitro Bbb Model

Activated leukocyte cell adhesion molecule (ALCAM) has been proposed to mediate leukocyte migration across the blood–brain barrier (BBB) in multiple sclerosis or experimental autoimmune encephalomyelitis (EAE). Here, we confirmed vascular ALCAM expression in human brain tissue samples in situ and on two different human in vitro BBB models. Antibody-mediated inhibition of ALCAM reduced diapedesis of human CD4+ Th1 but not of Th17 cells across the human BBB in vitro. In accordance to human Th1 cells, mouse Th1 cells showed reduced diapedesis across an ALCAM−/− in vitro BBB model under static but no longer under flow conditions. In contrast to the limited role of ALCAM in T cell extravasation across the BBB, we found a contribution of ALCAM to rolling, adhesion, and diapedesis of human CD14+ monocytes across the human BBB under flow and static conditions. Taken together, our study highlights the potential differences in the CNS expression of ALCAM in mouse and human and supports a prominent role for ALCAM in the multi-step extravasation of monocytes across the BBB.

scholarly journals Biotransformation modulates the penetration of metallic nanomaterials across an artificial blood–brain barrier model

2021 ◽  
Vol 118 (28) ◽  
pp. e2105245118
Author(s):  
Zhiling Guo ◽  
Peng Zhang ◽  
Swaroop Chakraborty ◽  
Andrew J Chetwynd ◽  
Fazel Abdolahpur Monikh ◽  
...  
Keyword(s):  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Complex Nature ◽  
Blood Brain ◽  
Blood Brain Barrier Model ◽  
Subsequent Behavior ◽  
Neurological Effects ◽  
In Vitro Bbb Model ◽  
The Brain

Understanding the potential of nanomaterials (NMs) to cross the blood–brain barrier (BBB), as a function of their physicochemical properties and subsequent behavior, fate, and adverse effect beyond that point, is vital for evaluating the neurological effects arising from their unintentional entry into the brain, which is yet to be fully explored. This is not only due to the complex nature of the brain but also the existing analytical limitations for characterization and quantification of NMs in the complex brain environment. By using a fit-for-purpose analytical workflow and an in vitro BBB model, we show that the physiochemical properties of metallic NMs influence their biotransformation in biological matrices, which in turn modulates the transport form, efficiency, amounts, and pathways of NMs through the BBB and, consequently, their neurotoxicity. The data presented here will support in silico modeling and prediction of the neurotoxicity of NMs and facilitate the tailored design of safe NMs.

scholarly journals Cellular Prion Protein Participates in Amyloid-β Transcytosis across the Blood—Brain Barrier

2012 ◽  
Vol 32 (4) ◽  
pp. 628-632 ◽  
Author(s):  
Thorsten Pflanzner ◽  
Benjamin Petsch ◽  
Bettina André-Dohmen ◽  
Andreas Müller-Schiffmann ◽  
Sabrina Tschickardt ◽  
...  
Keyword(s):  
Prion Protein ◽  
Blood Brain Barrier ◽  
Amyloid Β ◽  
Cellular Prion Protein ◽  
Brain Barrier ◽  
Putative Receptor ◽  
Blood Brain ◽  
In Vitro Bbb Model

The blood—brain barrier (BBB) facilitates amyloid-β (Aβ) exchange between the blood and the brain. Here, we found that the cellular prion protein (PrPc), a putative receptor implicated in mediating Aβ neurotoxicity in Alzheimer's disease (AD), participates in Aβ transcytosis across the BBB. Using an in vitro BBB model, [125I]-Aβ1–40 transcytosis was reduced by genetic knockout of PrPc or after addition of a competing PrPc-specific antibody. Furthermore, we provide evidence that PrPc is expressed in endothelial cells and, that monomeric Aβ1–40 binds to PrPc. These observations provide new mechanistic insights into the role of PrPc in AD.

scholarly journals Hydralazine is a Suitable Mimetic Agent of Hypoxia to Study the Impact of Hypoxic Stress on In Vitro Blood-Brain Barrier Model

2017 ◽  
Vol 42 (4) ◽  
pp. 1592-1602 ◽  
Author(s):  
Morgane Chatard ◽  
Clémentine Puech ◽  
Nathalie Perek ◽  
Frédéric Roche
Keyword(s):  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Hypoxic Stress ◽  
Cellular Mechanisms ◽  
Blood Brain ◽  
Junction Protein ◽  
Set Up ◽  
In Vitro Bbb Model ◽  
The Impact

Background/Aims: Understanding cellular mechanisms induced by hypoxia is fundamental to reduce blood-brain barrier (BBB) disruption. Nevertheless, the investigation of hypoxia on cellular pathways is complex with true hypoxia because HIF-1α has a short lifetime and rapidly reverts back to a normoxic state. To overcome this difficulty, mimetic agents of the hypoxia pathway have been developed, including the gold standard CoCl2. In this study, we proposed to compare CoCl2 and hydralazine in order to determine a suitable mimetic agent of hypoxia for the study on the BBB. Methods: We studied the cytotoxicity and the impact of these molecules on the integrity of an in vitro BBB model by comparing them to hypoxia controls. Results: We showed that the impact of hypoxic stress in our in vitro BBB model is rather similar between hydralazine and CoCl2. Chemical hypoxic stress led to an increase of BBB permeability either with CoCl2 or hydralazine. Tight junction protein expressions showed that this chemical hypoxic stress decreased ZO-1 but not occluding expressions, and cells had set up a defence mechanism by increasing expression and activity of their efflux transporters. Conclusion: Our results demonstrated that hydralazine is a better mimetic agent and more suitable than CoCl2 because it had the same effect but without the cytotoxic effect on in vitro BBB cells.

Sign in / Sign up

Export Citation Format

Share Document