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Al-Huthaifi AM, Radman BA, Al-Alawi AA, Mahmood F, Liu TB. Mechanisms and Virulence Factors of Cryptococcus neoformans Dissemination to the Central Nervous System. J Fungi (Basel) 2024; 10:586. [PMID: 39194911 DOI: 10.3390/jof10080586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2024] [Revised: 07/31/2024] [Accepted: 08/15/2024] [Indexed: 08/29/2024] Open
Abstract
Cryptococcosis is a prevalent fungal infection of the central nervous system (CNS) caused by Cryptococcus neoformans, a yeast with a polysaccharide capsule in the basidiomycete group. Normally, C. neoformans infects the respiratory tract and then breaches the blood-brain barrier (BBB), leading to meningitis or meningoencephalitis, which leads to hundreds of thousands of deaths each year. Although the mechanism by which C. neoformans infiltrates the BBB to invade the brain has yet to be fully understood, research has revealed that C. neoformans can cross the BBB using transcellular penetration, paracellular traversal, and infected phagocytes (the "Trojan horse" mechanism). The secretion of multiple virulence factors by C. neoformans is crucial in facilitating the spread of infection after breaching the BBB and causing brain infections. Extensive research has shown that various virulence factors play a significant role in the dissemination of infection beyond the lungs. This review explores the mechanisms of C. neoformans entering the CNS and explains how it bypasses the BBB. Additionally, it aims to understand the interplay between the regulatory mechanisms and virulence factors of C. neoformans.
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Affiliation(s)
| | - Bakeel A Radman
- Cancer Center, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510315, China
| | | | - Fawad Mahmood
- Medical Research Institute, Southwest University, Chongqing 400715, China
| | - Tong-Bao Liu
- Medical Research Institute, Southwest University, Chongqing 400715, China
- Jinfeng Laboratory, Chongqing 401329, China
- Engineering Research Center for Cancer Biomedical and Translational Medicine, Southwest University, Chongqing 400715, China
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Davis JM. A deep cut into early cryptococcal pathogenesis. mBio 2024; 15:e0065724. [PMID: 38975784 PMCID: PMC11323497 DOI: 10.1128/mbio.00657-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/09/2024] Open
Abstract
Dissemination from one organ system to another is common to many pathogens and often the key process separating simple illness from fatal infection. The pathogenic Cryptococcus species offer a prime example. Cryptococcal infection is thought to begin in the lungs, as a mild or asymptomatic pneumonia. However, bloodborne dissemination from the lungs to the brain is responsible for the most devastating forms of infection. As with other disseminating infections, the transition likely depends on rare but crucial events, such as the crossing of a tissue barrier. By their nature, these events are difficult to study. Francis et al. (mBio 15:e03078-23, 2024, https://doi.org/10.1128/mbio.03078-23) have addressed this difficulty by developing a powerful imaging pipeline to scan through unprecedented volumes of tissue from mice infected with Cryptococcus at multiple stages of infection. Their observations challenge some of our basic assumptions about cryptococcal pathogenesis, including when and how the organism reaches the bloodstream and the central nervous system.
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Affiliation(s)
- J. Muse Davis
- Stead Family Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
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Kwon S, Choi Y, Kim ES, Lee KT, Bahn YS, Jung KW. Pleiotropic roles of LAMMER kinase, Lkh1 in stress responses and virulence of Cryptococcus neoformans. Front Cell Infect Microbiol 2024; 14:1369301. [PMID: 38774630 PMCID: PMC11106425 DOI: 10.3389/fcimb.2024.1369301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 03/27/2024] [Indexed: 05/24/2024] Open
Abstract
Dual-specificity LAMMER kinases are highly evolutionarily conserved in eukaryotes and play pivotal roles in diverse physiological processes, such as growth, differentiation, and stress responses. Although the functions of LAMMER kinase in fungal pathogens in pathogenicity and stress responses have been characterized, its role in Cryptococcus neoformans, a human fungal pathogen and a model yeast of basidiomycetes, remains elusive. In this study, we identified a LKH1 homologous gene and constructed a strain with a deleted LKH1 and a complemented strain. Similar to other fungi, the lkh1Δ mutant showed intrinsic growth defects. We observed that C. neoformans Lkh1 was involved in diverse stress responses, including oxidative stress and cell wall stress. Particularly, Lkh1 regulates DNA damage responses in Rad53-dependent and -independent manners. Furthermore, the absence of LKH1 reduced basidiospore formation. Our observations indicate that Lkh1 becomes hyperphosphorylated upon treatment with rapamycin, a TOR protein inhibitor. Notably, LKH1 deletion led to defects in melanin synthesis and capsule formation. Furthermore, we found that the deletion of LKH1 led to the avirulence of C. neoformans in a systemic cryptococcosis murine model. Taken together, Lkh1 is required for the stress response, sexual differentiation, and virulence of C. neoformans.
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Affiliation(s)
- Sunhak Kwon
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, Jeonbuk, Republic of Korea
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Yeseul Choi
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Eui-Seong Kim
- Korea Zoonosis Research Institute, Jeonbuk National University, Iksan, Jeonbuk, Republic of Korea
| | - Kyung-Tae Lee
- Korea Zoonosis Research Institute, Jeonbuk National University, Iksan, Jeonbuk, Republic of Korea
| | - Yong-Sun Bahn
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Kwang-Woo Jung
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, Jeonbuk, Republic of Korea
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Mekala N, Trivedi J, Bhoj P, Togre N, Rom S, Sriram U, Persidsky Y. Alcohol and e-cigarette damage alveolar-epithelial barrier by activation of P2X7r and provoke brain endothelial injury via extracellular vesicles. Cell Commun Signal 2024; 22:39. [PMID: 38225580 PMCID: PMC10789007 DOI: 10.1186/s12964-023-01461-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 12/26/2023] [Indexed: 01/17/2024] Open
Abstract
BACKGROUND Use of nicotine containing products like electronic cigarettes (e-Cig) and alcohol are associated with mitochondrial membrane depolarization, resulting in the extracellular release of ATP, and mitochondrial DNA (mtDNA), mediating inflammatory responses. While nicotine effects on lungs is well-known, chronic alcohol (ETH) exposure also weakens lung immune responses and cause inflammation. Extracellular ATP (eATP) released by inflammatory/stressed cells stimulate purinergic P2X7 receptors (P2X7r) activation in adjacent cells. We hypothesized that injury caused by alcohol and e-Cig to pulmonary alveolar epithelial cells (hPAEpiC) promote the release of eATP, mtDNA and P2X7r in circulation. This induces a paracrine signaling communication either directly or via EVs to affect brain cells (human brain endothelial cells - hBMVEC). METHODS We used a model of primary human pulmonary alveolar epithelial cells (hPAEpiC) and exposed the cells to 100 mM ethanol (ETH), 100 µM acetaldehyde (ALD), or e-Cig (1.75 µg/mL of 1.8% or 0% nicotine) conditioned media, and measured the mitochondrial efficiency using Agilent Seahorse machine. Gene expression was measured by Taqman RT-qPCR and digital PCR. hPAEpiC-EVs were extracted from culture supernatant and characterized by flow cytometric analysis. Calcium (Ca2+) and eATP levels were quantified using commercial kits. To study intercellular communication via paracrine signaling or by EVs, we stimulated hBMVECs with hPAEpiC cell culture medium conditioned with ETH, ALD or e-cig or hPAEpiC-EVs and measured Ca2+ levels. RESULTS ETH, ALD, or e-Cig (1.8% nicotine) stimulation depleted the mitochondrial spare respiration capacity in hPAEpiC. We observed increased expression of P2X7r and TRPV1 genes (3-6-fold) and increased intracellular Ca2+ accumulation (20-30-fold increase) in hPAEpiC, resulting in greater expression of endoplasmic reticulum (ER) stress markers. hPAEpiC stimulated by ETH, ALD, and e-Cig conditioned media shed more EVs with larger particle sizes, carrying higher amounts of eATP and mtDNA. ETH, ALD and e-Cig (1.8% nicotine) exposure also increased the P2X7r shedding in media and via EVs. hPAEpiC-EVs carrying P2X7r and eATP cargo triggered paracrine signaling in human brain microvascular endothelial cells (BMVECs) and increased Ca2+ levels. P2X7r inhibition by A804598 compound normalized mitochondrial spare respiration, reduced ER stress and diminished EV release, thus protecting the BBB function. CONCLUSION Abusive drugs like ETH and e-Cig promote mitochondrial and endoplasmic reticulum stress in hPAEpiC and disrupts the cell functions via P2X7 receptor signaling. EVs released by lung epithelial cells against ETH/e-cig insults, carry a cargo of secondary messengers that stimulate brain cells via paracrine signals.
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Affiliation(s)
- Naveen Mekala
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Jayshil Trivedi
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Priyanka Bhoj
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Namdev Togre
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Slava Rom
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Uma Sriram
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA
| | - Yuri Persidsky
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA.
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Lanser DM, Bennett AB, Vu K, Gelli A. Macropinocytosis as a potential mechanism driving neurotropism of Cryptococcus neoformans. Front Cell Infect Microbiol 2023; 13:1331429. [PMID: 38149006 PMCID: PMC10750359 DOI: 10.3389/fcimb.2023.1331429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 11/27/2023] [Indexed: 12/28/2023] Open
Abstract
Cryptococcus neoformans can invade the central nervous system by crossing the blood-brain barrier via a transcellular mechanism that relies on multiple host factors. In this narrative, we review the evidence that a direct interplay between C. neoformans and brain endothelial cells forms the basis for invasion and transmigration across the brain endothelium. Adherence and internalization of C. neoformans is dependent on transmembrane proteins, including a hyaluronic acid receptor and an ephrin receptor tyrosine kinase. We consider the role of EphA2 in facilitating the invasion of the central nervous system by C. neoformans and highlight experimental evidence supporting macropinocytosis as a potential mechanism of internalization and transcytosis. How macropinocytosis might be conclusively demonstrated in the context of C. neoformans is also discussed.
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Affiliation(s)
| | | | | | - Angie Gelli
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, CA, United States
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Alanazi AH, Chastain DB, Rudraraju M, Parvathagiri V, Shan S, Lin X, Henao-Martínez AF, Franco-Paredes C, Narayanan SP, Somanath PR. A multi-arm, parallel, preclinical study investigating the potential benefits of acetazolamide, candesartan, and triciribine in combination with fluconazole for the treatment of cryptococcal meningoencephalitis. Eur J Pharmacol 2023; 960:176177. [PMID: 37931839 PMCID: PMC10985624 DOI: 10.1016/j.ejphar.2023.176177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 10/25/2023] [Accepted: 11/01/2023] [Indexed: 11/08/2023]
Abstract
Cryptococcus neoformans, an opportunistic fungal pathogen, primarily infects immunodeficient patients frequently causing cryptococcal meningoencephalitis (CM). Increased intracranial pressure (ICP) is a serious complication responsible for increased morbidity and mortality in CM patients. Non-invasive pharmacological agents that mitigate ICP could be beneficial in treating CM patients. The objective of the study was to investigate the efficacy of acetazolamide (AZA), candesartan (CAN), and triciribine (TCBN), in combination with the antifungal fluconazole, on C. neoformans-induced endothelial, brain, and lung injury in an experimental mouse model of CM. Our study shows that C. neoformans increases the expression of brain endothelial cell (BEC) junction proteins Claudin-5 (Cldn5) and VE-Cadherin to induce pathological cell-barrier remodeling and gap formation associated with increased Akt and p38 MAPK activation. All three agents inhibited C. neoformans-induced endothelial gap formation, only CAN and TCBN significantly reduced C. neoformans-induced Cldn5 expression, and only TCBN was effective in inhibiting Akt and p38MAPK. Interestingly, although C. neoformans did not cause brain or lung edema in mice, it induced lung and brain injuries, which were significantly reversed by AZA, CAN, or TCBN. Our study provides novel insights into the direct effects of C. neoformans on BECs in vitro, and the potential benefits of using AZA, CAN, or TCBN in the management of CM patients.
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Affiliation(s)
- Abdulaziz H Alanazi
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA, 30907, USA; Research Department, Charlie Norwood VA Medical Center, Augusta, GA, 30901, USA
| | - Daniel B Chastain
- Department of Clinical and Administrative Pharmacy, University of Georgia College of Pharmacy, SWGA Clinical Campus, Phoebe Putney Memorial Hospital, Albany, GA, 31701, USA
| | - Madhuri Rudraraju
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA, 30907, USA; Research Department, Charlie Norwood VA Medical Center, Augusta, GA, 30901, USA
| | - Varun Parvathagiri
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA, 30907, USA; Research Department, Charlie Norwood VA Medical Center, Augusta, GA, 30901, USA
| | - Shengshuai Shan
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA, 30907, USA; Research Department, Charlie Norwood VA Medical Center, Augusta, GA, 30901, USA
| | - Xiaorong Lin
- Department of Microbiology, University of Georgia, Athens, GA, 30602, USA
| | - Andrés F Henao-Martínez
- Division of Infectious Diseases, University of Colorado, Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Carlos Franco-Paredes
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, 80523, USA; Hospital Infantil de México, Federico Gómez, México City, 06720, Mexico
| | - S Priya Narayanan
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA, 30907, USA; Research Department, Charlie Norwood VA Medical Center, Augusta, GA, 30901, USA
| | - Payaningal R Somanath
- Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA, 30907, USA; Research Department, Charlie Norwood VA Medical Center, Augusta, GA, 30901, USA.
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Alanazi F, Raghunandanan S, Priya R, Yang XF. The Rrp2-RpoN-RpoS pathway plays an important role in the blood-brain barrier transmigration of the Lyme disease pathogen. Infect Immun 2023; 91:e0022723. [PMID: 37874144 PMCID: PMC10652863 DOI: 10.1128/iai.00227-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 09/14/2023] [Indexed: 10/25/2023] Open
Abstract
Lyme disease, caused by Borrelia (or Borreliella) burgdorferi, is a complex multisystemic disorder that includes Lyme neuroborreliosis resulting from the invasion of both the central and peripheral nervous systems. However, factors that enable the pathogen to cross the blood-brain barrier (BBB) and invade the central nervous system (CNS) are still not well understood. The objective of this study was to identify the B. burgdorferi factors required for BBB transmigration. We utilized a transwell BBB model based on human brain-microvascular endothelial cells and focused on investigating the Rrp2-RpoN-RpoS pathway, a central regulatory pathway that is essential for mammalian infection by B. burgdorferi. Our results demonstrated that the Rrp2-RpoN-RpoS pathway is crucial for BBB transmigration. Furthermore, we identified OspC, a major surface lipoprotein controlled by the Rrp2-RpoN-RpoS pathway, as a significant contributor to BBB transmigration. Constitutive production of OspC in a mutant defective in the Rrp2-RpoN-RpoS pathway did not rescue the impairment in BBB transmigration, indicating that this pathway controls additional factors for this process. Two other major surface lipoproteins controlled by this pathway, DbpA/B and BBK32, appeared to be dispensable for BBB transmigration. In addition, both the surface lipoprotein OspA and the Rrp1 pathway, which are required B. burgdorferi colonization in the tick vector, were found not required for BBB transmigration. Collectively, our findings using in vitro transwell assays uncover another potential role of the Rrp2-RpoN-RpoS pathway in BBB transmigration of B. burgdorferi and invasion into the CNS.
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Affiliation(s)
- Fuad Alanazi
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Sajith Raghunandanan
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Raj Priya
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - X. Frank Yang
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, USA
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Mekala N, Trivedi J, Bhoj P, Togre N, Rom S, Sriram U, Persidsky Y. Alcohol and e-cigarette damage alveolar-epithelial barrier by activation of P2X7r and provoke brain endothelial injury via extracellular vesicles. RESEARCH SQUARE 2023:rs.3.rs-3552555. [PMID: 38014253 PMCID: PMC10680944 DOI: 10.21203/rs.3.rs-3552555/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Background Use of nicotine containing products like electronic cigarettes (e-Cig) and alcohol are associated with mitochondrial membrane depolarization, resulting in the extracellular release of ATP, and mitochondrial DNA (mtDNA), mediating inflammatory responses. While nicotine effects on lungs is well-known, chronic alcohol (ETH) exposure also weakens lung immune responses and cause inflammation. Extracellular ATP (eATP) released by inflammatory/stressed cells stimulate purinergic P2X7 receptors (P2X7r) activation in adjacent cells. We hypothesized that injury caused by alcohol and e-Cig to pulmonary alveolar epithelial cells (hPAEpiC) promote the release of eATP, mtDNA and P2X7r in circulation. This induces a paracrine signaling communication either directly or via EVs to affect brain cells (human brain endothelial cells - hBMVEC). Methods We used a model of primary human pulmonary alveolar epithelial cells (hPAEpiC) and exposed the cells to 100 mM ethanol (ETH), 100 μM acetaldehyde (ALD), or e-Cig (1.75μg/mL of 1.8% or 0% nicotine) conditioned media, and measured the mitochondrial efficiency using Agilent Seahorse machine. Gene expression was measured by Taqman RT-qPCR and digital PCR. hPAEpiC-EVs were extracted from culture supernatant and characterized by flow cytometric analysis. Calcium (Ca2+) and eATP levels were quantified using commercial kits. To study intercellular communication via paracrine signaling or by EVs, we stimulated hBMVECs with hPAEpiC cell culture medium conditioned with ETH, ALD or e-cig or hPAEpiC-EVs and measured Ca2+ levels. Results ETH, ALD, or e-Cig (1.8% nicotine) stimulation depleted the mitochondrial spare respiration capacity in hPAEpiC. We observed increased expression of P2X7r and TRPV1 genes (3-6-fold) and increased intracellular Ca2+ accumulation (20-30-fold increase) in hPAEpiC, resulting in greater expression of endoplasmic reticulum (ER) stress markers. hPAEpiC stimulated by ETH, ALD, and e-Cig conditioned media shed more EVs with larger particle sizes, carrying higher amounts of eATP and mtDNA. ETH, ALD and e-Cig (1.8% nicotine) exposure also increased the P2X7r shedding in media and via EVs. hPAEpiC-EVs carrying P2X7r and eATP cargo triggered paracrine signaling in human brain microvascular endothelial cells (BMVECs) and increased Ca2+ levels. P2X7r inhibition by A804598 compound normalized mitochondrial spare respiration, reduced ER stress and diminished EV release, thus protecting the BBB function. Conclusion Abusive drugs like ETH and e-Cig promote mitochondrial and endoplasmic reticulum stress in hPAEpiC and disrupts the cell functions via P2X7 receptor signaling. EVs released by lung epithelial cells against ETH/e-cig insults, carry a cargo of secondary messengers that stimulate brain cells via paracrine signals.
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Mihailova L, Shalabalija D, Zimmer A, Geskovski N, Makreski P, Petrushevska M, Simonoska Crcarevska M, Glavas Dodov M. Comparative Studies of the Uptake and Internalization Pathways of Different Lipid Nano-Systems Intended for Brain Delivery. Pharmaceutics 2023; 15:2082. [PMID: 37631296 PMCID: PMC10458318 DOI: 10.3390/pharmaceutics15082082] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/14/2023] [Accepted: 08/01/2023] [Indexed: 08/27/2023] Open
Abstract
Lipid nano-systems were prepared and characterized in a series of well-established in vitro tests that could assess their interactions with the hCMEC/D3 and SH-SY5Y cell lines as a model for the blood-brain barrier and neuronal function, accordingly. The prepared formulations of nanoliposomes and nanostructured lipid carriers were characterized by z-average diameters of ~120 nm and ~105 nm, respectively, following a unimodal particle size distribution (PDI < 0.3) and negative Z-potential (-24.30 mV to -31.20 mV). Stability studies implied that the nano-systems were stable in a physiologically relevant medium as well as human plasma, except nanoliposomes containing poloxamer on their surface, where there was an increase in particle size of ~26%. The presence of stealth polymer tends to decrease the amount of adsorbed proteins onto a particle's surface, according to protein adsorption studies. Both formulations of nanoliposomes were characterized by a low cytotoxicity, while their cell viability was reduced when incubated with the highest concentration (100 μg/mL) of nanostructured lipid formulations, which could have been associated with the consumption of cellular energy, thus resulting in a reduction in metabolic active cells. The uptake of all the nano-systems in the hCMEC/D3 and SH-SY5Y cell lines was successful, most likely following ATP-dependent internalization, as well as transport via passive diffusion.
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Affiliation(s)
- Ljubica Mihailova
- Institute of Pharmaceutical Technology, Faculty of Pharmacy, Ss. Cyril and Methodius University in Skopje, Majka Tereza 47, 1000 Skopje, North Macedonia; (L.M.); (D.S.); (N.G.); (M.S.C.); (M.G.D.)
| | - Dushko Shalabalija
- Institute of Pharmaceutical Technology, Faculty of Pharmacy, Ss. Cyril and Methodius University in Skopje, Majka Tereza 47, 1000 Skopje, North Macedonia; (L.M.); (D.S.); (N.G.); (M.S.C.); (M.G.D.)
| | - Andreas Zimmer
- Department of Pharmaceutical Technology and Biopharmacy, Institute of Pharmaceutical Sciences, University of Graz, Universitatplatz 1/EG, A-8010 Graz, Austria
| | - Nikola Geskovski
- Institute of Pharmaceutical Technology, Faculty of Pharmacy, Ss. Cyril and Methodius University in Skopje, Majka Tereza 47, 1000 Skopje, North Macedonia; (L.M.); (D.S.); (N.G.); (M.S.C.); (M.G.D.)
| | - Petre Makreski
- Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Ss. Cyril and Methodius University in Skopje, Arhimedova 5, 1000 Skopje, North Macedonia;
| | - Marija Petrushevska
- Institute of Pharmacology and Toxicology, Faculty of Medicine, Ss. Cyril and Methodius University in Skopje, 50 Divizija 6, 1000 Skopje, North Macedonia;
| | - Maja Simonoska Crcarevska
- Institute of Pharmaceutical Technology, Faculty of Pharmacy, Ss. Cyril and Methodius University in Skopje, Majka Tereza 47, 1000 Skopje, North Macedonia; (L.M.); (D.S.); (N.G.); (M.S.C.); (M.G.D.)
| | - Marija Glavas Dodov
- Institute of Pharmaceutical Technology, Faculty of Pharmacy, Ss. Cyril and Methodius University in Skopje, Majka Tereza 47, 1000 Skopje, North Macedonia; (L.M.); (D.S.); (N.G.); (M.S.C.); (M.G.D.)
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10
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Hartl N, Gabold B, Adams F, Uhl P, Oerter S, Gätzner S, Metzger M, König AC, Hauck SM, Appelt-Menzel A, Mier W, Fricker G, Merkel OM. Overcoming the blood-brain barrier? - prediction of blood-brain permeability of hydrophobically modified polyethylenimine polyplexes for siRNA delivery into the brain with in vitro and in vivo models. J Control Release 2023; 360:613-629. [PMID: 37437848 DOI: 10.1016/j.jconrel.2023.07.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 06/23/2023] [Accepted: 07/08/2023] [Indexed: 07/14/2023]
Abstract
The blood-brain barrier (BBB) is a highly selective biological barrier that represents a major bottleneck in the treatment of all types of central nervous system (CNS) disorders. Small interfering RNA (siRNA) offers in principle a promising therapeutic approach, e.g., for brain tumors, by downregulating brain tumor-related genes and inhibiting tumor growth via RNA interference. In an effort to develop efficient siRNA nanocarriers for crossing the BBB, we utilized polyethyleneimine (PEI) polymers hydrophobically modified with either stearic-acid (SA) or dodecylacrylamide (DAA) subunits and evaluated their suitability for delivering siRNA across the BBB in in vitro and in vivo BBB models depending on their structure. Physicochemical characteristics of siRNA-polymer complexes (polyplexes (PXs)), e.g., particle size and surface charge, were measured by dynamic light scattering and laser Doppler anemometry, whereas siRNA condensation ability of polymers and polyplex stability was evaluated by spectrophotometric methods. The composition of the biomolecule corona that absorbs on polyplexes upon encountering physiological fluids was investigated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and by a liquid chromatography-tandem mass spectrometry (LC-MS-MS) method. Cellular internalization abilities of PXs into brain endothelial cells (hCMEC/D3) was confirmed, and a BBB permeation assay using a human induced pluripotent stem cell (hiPSC)-derived BBB model revealed similar abilities to cross the BBB for all formulations under physiological conditions. However, biodistribution studies of radiolabeled PXs in mice were inconsistent with in vitro results as the detected amount of radiolabeled siRNA in the brain delivered with PEI PXs was higher compared to PEI-SA PXs. Taken together, PEI PXs were shown to be a suitable nanocarrier to deliver small amounts of siRNA across the BBB into the brain but more sophisticated human BBB models that better represent physiological conditions and biodistribution are required to provide highly predictive in vitro data for human CNS drug development in the future.
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Affiliation(s)
- Natascha Hartl
- Ludwig-Maximilians-University, Pharmaceutical Technology and Biopharmaceutics, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Bettina Gabold
- Ludwig-Maximilians-University, Pharmaceutical Technology and Biopharmaceutics, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Friederike Adams
- University of Stuttgart, Institute of Polymer Chemistry, Macromolecular Materials and Fiber Chemistry, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Philipp Uhl
- University Hospital Heidelberg, Department of Nuclear Medicine, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany
| | - Sabrina Oerter
- Fraunhofer Institute for Silicate Research (ISC), Translational Center Regenerative Therapies (TLC-RT), 97070 Würzburg, Germany; University Hospital Würzburg, Chair of Tissue Engineering and Regenerative Medicine (TERM), 97070 Würzburg, Germany
| | - Sabine Gätzner
- Fraunhofer Institute for Silicate Research (ISC), Translational Center Regenerative Therapies (TLC-RT), 97070 Würzburg, Germany
| | - Marco Metzger
- Fraunhofer Institute for Silicate Research (ISC), Translational Center Regenerative Therapies (TLC-RT), 97070 Würzburg, Germany; University Hospital Würzburg, Chair of Tissue Engineering and Regenerative Medicine (TERM), 97070 Würzburg, Germany
| | - Ann-Christine König
- Helmholtz Centrum Munich - German Research Center for Environmental Health, Research Unit Protein Science, Heidemannsstr. 1, 80939, Munich, Germany
| | - Stefanie M Hauck
- Helmholtz Centrum Munich - German Research Center for Environmental Health, Research Unit Protein Science, Heidemannsstr. 1, 80939, Munich, Germany
| | - Antje Appelt-Menzel
- Fraunhofer Institute for Silicate Research (ISC), Translational Center Regenerative Therapies (TLC-RT), 97070 Würzburg, Germany; University Hospital Würzburg, Chair of Tissue Engineering and Regenerative Medicine (TERM), 97070 Würzburg, Germany
| | - Walter Mier
- University Hospital Heidelberg, Department of Nuclear Medicine, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany
| | - Gert Fricker
- University of Heidelberg, Institute for Pharmacy & Molekular Biotechnology, Im Neuenheimer Feld 329, 69120 Heidelberg, Germany
| | - Olivia M Merkel
- Ludwig-Maximilians-University, Pharmaceutical Technology and Biopharmaceutics, Butenandtstr. 5-13, 81377, Munich, Germany.
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11
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Hsiao MY, Liao D, Xiang G, Zhong P. Intercellular Calcium Waves and Permeability Change Induced by Vertically Deployed Surface Acoustic Waves in a Human Cerebral Microvascular Endothelial Cell Line (hCMEC/D3) Monolayer. ULTRASOUND IN MEDICINE & BIOLOGY 2023; 49:1153-1163. [PMID: 36764884 PMCID: PMC10050144 DOI: 10.1016/j.ultrasmedbio.2022.12.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 11/28/2022] [Accepted: 12/29/2022] [Indexed: 05/11/2023]
Abstract
OBJECTIVE The ultrasound-mediated blood-brain barrier (BBB) opening with microbubbles has been widely employed, while recent studies also indicate the possibility that ultrasound alone can open the BBB through a direct mechanical effect. However, the exact mechanisms through which ultrasound interacts with the BBB and whether it can directly trigger intracellular signaling and a permeability change in the BBB endothelium remain unclear. METHODS Vertically deployed surface acoustic waves (VD-SAWs) were applied on a human cerebral microvascular endothelial cell line (hCMEC/D3) monolayer using a 33-MHz interdigital transducer that exerts shear stress-predominant stimulation. The intracellular calcium response was measured by fluorescence imaging, and the permeability of the hCMEC/D3 monolayer was assessed by transendothelial electrical resistance (TEER). DISCUSSION At a certain intensity threshold, VD-SAWs induced an intracellular calcium surge that propagated to adjacent cells as intercellular calcium waves. VD-SAWs induced a TEER decrease in a pulse repetition frequency-dependent manner, thereby suggesting possible involvement of the mechanosensitive ion channels. CONCLUSION The unique VD-SAW system enables more physiological mechanical stimulation of the endothelium monolayer. Moreover, it can be easily combined with other measurement devices, providing a useful platform for further mechanistic studies on ultrasound-mediated BBB opening.
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Affiliation(s)
- Ming-Yen Hsiao
- Department of Physical Medicine and Rehabilitation, College of Medicine, National Taiwan University, Taipei, Taiwan; Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Taipei, Taiwan.
| | - Defei Liao
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA
| | - Gaoming Xiang
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA
| | - Pei Zhong
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA
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12
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Lee HH, Carmichael DJ, Ríbeiro V, Parisi DN, Munzen ME, Charles-Niño CL, Hamed MF, Kaur E, Mishra A, Patel J, Rooklin RB, Sher A, Carrillo-Sepulveda MA, Eugenin EA, Dores MR, Martinez LR. Glucuronoxylomannan intranasal challenge prior to Cryptococcus neoformans pulmonary infection enhances cerebral cryptococcosis in rodents. PLoS Pathog 2023; 19:e1010941. [PMID: 37115795 PMCID: PMC10171644 DOI: 10.1371/journal.ppat.1010941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 05/10/2023] [Accepted: 04/17/2023] [Indexed: 04/29/2023] Open
Abstract
The encapsulated fungus Cryptococcus neoformans is the most common cause of fungal meningitis, with the highest rate of disease in patients with AIDS or immunosuppression. This microbe enters the human body via inhalation of infectious particles. C. neoformans capsular polysaccharide, in which the major component is glucuronoxylomannan (GXM), extensively accumulates in tissues and compromises host immune responses. C. neoformans travels from the lungs to the bloodstream and crosses to the brain via transcytosis, paracytosis, or inside of phagocytes using a "Trojan horse" mechanism. The fungus causes life-threatening meningoencephalitis with high mortality rates. Hence, we investigated the impact of intranasal exogenous GXM administration on C. neoformans infection in C57BL/6 mice. GXM enhances cryptococcal pulmonary infection and facilitates fungal systemic dissemination and brain invasion. Pre-challenge of GXM results in detection of the polysaccharide in lungs, serum, and surprisingly brain, the latter likely reached through the nasal cavity. GXM significantly alters endothelial cell tight junction protein expression in vivo, suggesting significant implications for the C. neoformans mechanisms of brain invasion. Using a microtiter transwell system, we showed that GXM disrupts the trans-endothelial electrical resistance, weakening human brain endothelial cell monolayers co-cultured with pericytes, supportive cells of blood vessels/capillaries found in the blood-brain barrier (BBB) to promote C. neoformans BBB penetration. Our findings should be considered in the development of therapeutics to combat the devastating complications of cryptococcosis that results in an estimated ~200,000 deaths worldwide each year.
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Affiliation(s)
- Hiu Ham Lee
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York, United States of America
| | - Dylan J Carmichael
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York, United States of America
| | - Victoria Ríbeiro
- Department of Neuroscience, Cell Biology, and Anatomy, The University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Dana N Parisi
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York, United States of America
- Department of Biomedical Sciences, Long Island University-Post, Brookville, New York, United States of America
| | - Melissa E Munzen
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, United States of America
| | - Claudia L Charles-Niño
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, United States of America
| | - Mohamed F Hamed
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, United States of America
- Department of Pathology, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt
| | - Ettiman Kaur
- Department of Biology, Hofstra University, Hempstead, New York, United States of America
| | - Ayush Mishra
- Department of Biology, Hofstra University, Hempstead, New York, United States of America
| | - Jiya Patel
- Department of Biology, Hofstra University, Hempstead, New York, United States of America
| | - Rikki B Rooklin
- Department of Biology, Hofstra University, Hempstead, New York, United States of America
| | - Amina Sher
- Department of Biology, Hofstra University, Hempstead, New York, United States of America
| | - Maria A Carrillo-Sepulveda
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York, United States of America
| | - Eliseo A Eugenin
- Department of Neuroscience, Cell Biology, and Anatomy, The University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Michael R Dores
- Department of Biology, Hofstra University, Hempstead, New York, United States of America
| | - Luis R Martinez
- Department of Biomedical Sciences, NYIT College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York, United States of America
- Department of Biomedical Sciences, Long Island University-Post, Brookville, New York, United States of America
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, United States of America
- Emerging Pathogens Institute, University of Florida, Gainesville, Florida, United States of America
- Center for Immunology and Transplantation, University of Florida, Gainesville, Florida, United States of America
- Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, Florida, United States of America
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13
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Spadari CC, Lanser DM, Araújo MV, De Jesus DFF, Lopes LB, Gelli A, Ishida K. Oral delivery of brain-targeted miltefosine-loaded alginate nanoparticles functionalized with polysorbate 80 for the treatment of cryptococcal meningitis. J Antimicrob Chemother 2023; 78:1092-1101. [PMID: 36881722 PMCID: PMC10319950 DOI: 10.1093/jac/dkad053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 02/15/2023] [Indexed: 03/09/2023] Open
Abstract
OBJECTIVES To develop alginate nanoparticles functionalized with polysorbate 80 (P80) as miltefosine carriers for brain targeting in the oral treatment of cryptococcal meningitis. METHODS Miltefosine-loaded alginate nanoparticles functionalized or not with P80 were produced by an emulsification/external gelation method and the physicochemical characteristics were determined. The haemolytic activity and cytotoxic and antifungal effects of nanoparticles were assessed in an in vitro model of the blood-brain barrier (BBB). A murine model of disseminated cryptococcosis was used for testing the efficacy of oral treatment with the nanoparticles. In addition, serum biomarkers were measured for toxicity evaluation and the nanoparticle biodistribution was analysed. RESULTS P80-functionalized nanoparticles had a mean size of ∼300 nm, a polydispersity index of ∼0.4 and zeta potential around -50 mV, and they promoted a sustained drug release. Both nanoparticles were effective in decreasing the infection process across the BBB model and reduced drug cytotoxicity and haemolysis. In in vivo cryptococcosis, the oral treatment with two doses of P80 nanoparticles reduced the fungal burden in the brain and lungs, while the non-functionalized nanoparticles reduced fungal amount only in the lungs, and the free miltefosine was not effective. In addition, the P80-functionalization improved the nanoparticle distribution in several organs, especially in the brain. Finally, treatment with nanoparticles did not cause any toxicity in animals. CONCLUSIONS These results support the potential use of P80-functionalized alginate nanoparticles as miltefosine carriers for non-toxic and effective alternative oral treatment, enabling BBB translocation and reduction of fungal infection in the brain.
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Affiliation(s)
- Cristina C Spadari
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Dylan M Lanser
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, USA
| | - Marcelo V Araújo
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Daniel F F De Jesus
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Luciana B Lopes
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Angie Gelli
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, USA
| | - Kelly Ishida
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
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14
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Li X, Cai Q, Wilson BA, Fan H, Dave H, Giannotta M, Bachoo R, Qin Z. Mechanobiological modulation of blood-brain barrier permeability by laser stimulation of endothelial-targeted nanoparticles. NANOSCALE 2023; 15:3387-3397. [PMID: 36722886 PMCID: PMC10129863 DOI: 10.1039/d2nr05062e] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The blood-brain barrier (BBB) maintains an optimal environment for brain homeostasis but excludes most therapeutics from entering the brain. Strategies that reversibly increase BBB permeability are essential for treating brain diseases and are the focus of significant preclinical and translational interest. Picosecond laser excitation of tight junction-targeted gold nanoparticles (AuNPs) generates a nanoscale mechanical perturbation and induces a graded and reversible increase in BBB permeability (OptoBBB). Here we advanced this technique by showing that targeting endothelial glycoproteins leads to >10-fold higher targeting efficiency than targeting tight junctions both in vitro and in vivo. With both tight-junction and glycoprotein targeting, we demonstrate that OptoBBB is associated with a transient elevation and propagation of Ca2+, actin polymerization, and phosphorylation of ERK1/2 (extracellular signal-regulated protein kinase). These collectively activate the cytoskeleton resulting in increased paracellular permeability. The Ca2+ response involves internal Ca2+ depletion and Ca2+ influx with contributions from mechanosensitive ion channels (TRPV4, Piezo1). We provide insight into how the excitation of tight junction protein (JAM-A)-targeted and endothelial (glycocalyx)-targeted AuNPs leads to similar mechanobiological modulation of BBB permeability while targeting the glycocalyx significantly improves the nanoparticle accumulation in the brain. The results will be critical for guiding the future development of this technology for brain disease treatment.
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Affiliation(s)
- Xiaoqing Li
- Department of Bioengineering, the University of Texas at Dallas, Richardson, TX, 75080, USA.
| | - Qi Cai
- Department of Mechanical Engineering, the University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Blake A Wilson
- Department of Mechanical Engineering, the University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Hanwen Fan
- Department of Mechanical Engineering, the University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Harsh Dave
- Department of Bioengineering, the University of Texas at Dallas, Richardson, TX, 75080, USA.
| | - Monica Giannotta
- Institute of Molecular Oncology Foundation (IFOM), 20139 Milan, Italy.
| | - Robert Bachoo
- Department of Internal Medicine, the University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
- Harold C. Simmons Comprehensive Cancer Center, the University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Neurology, the University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Zhenpeng Qin
- Department of Bioengineering, the University of Texas at Dallas, Richardson, TX, 75080, USA.
- Department of Mechanical Engineering, the University of Texas at Dallas, Richardson, TX, 75080, USA
- Center for Advanced Pain Studies, the University of Texas at Dallas, Richardson, TX 75080, USA
- Department of Surgery, the University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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15
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Nielson JA, Davis JM. Roles for Microglia in Cryptococcal Brain Dissemination in the Zebrafish Larva. Microbiol Spectr 2023; 11:e0431522. [PMID: 36719205 PMCID: PMC10100726 DOI: 10.1128/spectrum.04315-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 12/20/2022] [Indexed: 02/01/2023] Open
Abstract
Cryptococcal infection begins in the lungs, but yeast cells subsequently access the bloodstream, from which they can reach the central nervous system (CNS). The resulting meningoencephalitis is the most common presentation and is very difficult to treat. How this fungus interacts with the blood-brain barrier (BBB) and establishes growth in the brain parenchyma remains a central question in fungal pathogenesis. We and others have developed the zebrafish larva as a model host for cryptococcosis and demonstrated that hematogenous CNS infection is replicated in this model. Here, we have used this model to examine the details of BBB crossing and the events immediately before and after. We have observed multiple mechanisms of BBB crossing and found that microglia, the resident phagocytes of the brain, likely have multiple roles. First, microglia either actively transfer yeast cells across the BBB or take up a significant proportion of them immediately after crossing. Second, microglia are capable of clearing individual cryptococcal cells at a developmental stage before adaptive immune cells have emerged. Third, microglia serve to maintain endothelial integrity, preventing other, phagocyte-independent forms of crossing. These proposed microglial functions during infection in the zebrafish larva generate new hypotheses concerning the establishment and control of cryptococcal meningoencephalitis. IMPORTANCE Cryptococcal meningitis is a fungal infection of the brain and a major cause of death in people with uncontrolled HIV. Infection begins in the lungs but can enter the bloodstream and disseminate to the brain. A structure called the blood-brain barrier must be crossed for the fungus to enter and cause meningitis. Learning how Cryptococcus crosses the blood-brain barrier will be crucial to understanding and possibly preventing brain infection. Using the zebrafish larva as a model host, we show that microglia, the resident phagocytes of the brain, potentially play multiple previously unappreciated roles in cryptococcal infection of the brain. These roles include reinforcing the integrity of the blood-brain barrier, clearing cryptococcal cells after they have crossed, and possibly participating directly in crossing via a previously unknown mechanism.
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Affiliation(s)
- Jacquelyn A. Nielson
- Stead Family Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, USA
| | - J. Muse Davis
- Stead Family Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, USA
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16
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Zoladek J, Burlaud-Gaillard J, Chazal M, Desgraupes S, Jeannin P, Gessain A, Pardigon N, Hubert M, Roingeard P, Jouvenet N, Afonso PV. Human Claudin-Derived Peptides Block the Membrane Fusion Process of Zika Virus and Are Broad Flavivirus Inhibitors. Microbiol Spectr 2022; 10:e0298922. [PMID: 36040168 PMCID: PMC9603178 DOI: 10.1128/spectrum.02989-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 08/15/2022] [Indexed: 01/04/2023] Open
Abstract
Zika virus (ZIKV) is a mosquito-borne flavivirus that emerged in the Pacific islands in 2007 and spread to the Americas in 2015. The infection remains asymptomatic in most cases but can be associated with severe neurological disorders. Despite massive efforts, no specific drug or vaccine against ZIKV infection is available to date. Claudins are tight-junction proteins that favor the entry of several flaviviruses, including ZIKV. In this study, we identified two peptides derived from the N-terminal sequences of claudin-7 and claudin-1, named CL7.1 and CL1.1, respectively, that inhibited ZIKV infection in a panel of human cell lines. Using cell-to-cell fusion assays, we demonstrated that these peptides blocked the ZIKV E-mediated membrane fusion. A comparison of the antiviral efficacy of CL1.1 and CL7.1 pointed to the importance of the peptide amphipathicity. Electron microscopic analysis revealed that CL1.1 altered the ultrastructure of the viral particles likely by binding the virus lipid envelope. However, amphipathicity could not fully explain the antiviral activity of CL1.1. In silico docking simulations suggested that CL1.1 may also interact with the E protein, near its stem region. Overall, our data suggested that claudin-derived peptides inhibition may be linked to simultaneous interaction with the E protein and the viral lipid envelope. Finally, we found that CL1.1 also blocked infection by yellow fever and Japanese encephalitis viruses but not by HIV-1 or SARS-CoV-2. Our results provide a basis for the future development of therapeutics against a wide range of endemic and emerging flaviviruses. IMPORTANCE Zika virus (ZIKV) is a flavivirus transmitted by mosquito bites that have spread to the Pacific Islands and the Americas over the past decade. The infection remains asymptomatic in most cases but can cause severe neurological disorders. ZIKV is a major public health threat in areas of endemicity, and there is currently no specific antiviral drug or vaccine available. We identified two antiviral peptides deriving from the N-terminal sequences of claudin-7 and claudin-1 with the latter being the most effective. These peptides block the envelope-mediated membrane fusion. Our data suggested that the inhibition was likely achieved by simultaneously interacting with the viral lipid envelope and the E protein. The peptides also inhibited other flaviviruses. These results could provide the basis for the development of therapies that might target a wide array of flaviviruses from current epidemics and possibly future emergences.
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Affiliation(s)
- Jim Zoladek
- Unité Épidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Université Paris Cité, CNRS UMR 3569, Paris, France
| | - Julien Burlaud-Gaillard
- Inserm U1259 MAVIVH, Université de Tours and CHRU de Tours, Tours, France
- Plate-Forme IBiSA de Microscopie Electronique, Université de Tours and CHRU de Tours, Tours, France
| | - Maxime Chazal
- Unité Signalisation Antivirale, Institut Pasteur, Université Paris Cité, CNRS UMR 3569, Paris, France
| | - Sophie Desgraupes
- Unité Épidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Université Paris Cité, CNRS UMR 3569, Paris, France
| | - Patricia Jeannin
- Unité Épidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Université Paris Cité, CNRS UMR 3569, Paris, France
| | - Antoine Gessain
- Unité Épidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Université Paris Cité, CNRS UMR 3569, Paris, France
| | - Nathalie Pardigon
- Groupe Arbovirus, Unité Environnement et Risques Infectieux, Institut Pasteur, Université Paris Cité, Paris, France
| | - Mathieu Hubert
- Unité Virus et Immunité, Institut Pasteur, Université Paris Cité, CNRS UMR 3569, Paris, France
| | - Philippe Roingeard
- Inserm U1259 MAVIVH, Université de Tours and CHRU de Tours, Tours, France
- Plate-Forme IBiSA de Microscopie Electronique, Université de Tours and CHRU de Tours, Tours, France
| | - Nolwenn Jouvenet
- Unité Signalisation Antivirale, Institut Pasteur, Université Paris Cité, CNRS UMR 3569, Paris, France
| | - Philippe V. Afonso
- Unité Épidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Université Paris Cité, CNRS UMR 3569, Paris, France
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Mekala N, Gheewala N, Rom S, Sriram U, Persidsky Y. Blocking of P2X7r Reduces Mitochondrial Stress Induced by Alcohol and Electronic Cigarette Exposure in Brain Microvascular Endothelial Cells. Antioxidants (Basel) 2022; 11:1328. [PMID: 35883819 PMCID: PMC9311929 DOI: 10.3390/antiox11071328] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 06/27/2022] [Accepted: 07/03/2022] [Indexed: 12/15/2022] Open
Abstract
Studies in both humans and animal models demonstrated that chronic alcohol/e-cigarette (e-Cig) exposure affects mitochondrial function and impairs barrier function in brain microvascular endothelial cells (BMVECs). Identification of the signaling pathways by which chronic alcohol/e-Cig exposure induces mitochondrial damage in BMVEC is vital for protection of the blood-brain barrier (BBB). To address the issue, we treated human BMVEC [hBMVECs (D3 cell-line)] with ethanol (ETH) [100 mM], acetaldehyde (ALD) [100 μM], or e-cigarette (e-Cig) [35 ng/mL of 1.8% or 0% nicotine] conditioned medium and showed reduced mitochondrial oxidative phosphorylation (OXPHOS) measured by a Seahorse analyzer. Seahorse data were further complemented with the expression of mitochondrial OXPHOS proteins detected by Western blots. We also observed cytosolic escape of ATP and its extracellular release due to the disruption of mitochondrial membrane potential caused by ETH, ALD, or 1.8% e-Cig exposure. Moreover ETH, ALD, or 1.8% e-Cig treatment resulted in elevated purinergic P2X7r and TRPV1 channel gene expression, measured using qPCR. We also demonstrated the protective role of P2X7r antagonist A804598 (10 μM) in restoring mitochondrial oxidative phosphorylation levels and preventing extracellular ATP release. In a BBB functional assay using trans-endothelial electrical resistance, we showed that blocking the P2X7r channel enhanced barrier function. In summary, we identified the potential common pathways of mitochondrial injury caused by ETH, ALD, and 1.8% e-Cig which allow new protective interventions. We are further investigating the potential link between P2X7 regulatory pathways and mitochondrial health.
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Affiliation(s)
| | | | | | | | - Yuri Persidsky
- Department of Pathology and Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA; (N.M.); (N.G.); (S.R.); (U.S.)
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Adams Y, Jensen AR. Cerebral malaria - modelling interactions at the blood-brain barrier in vitro. Dis Model Mech 2022; 15:275963. [PMID: 35815443 PMCID: PMC9302004 DOI: 10.1242/dmm.049410] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The blood–brain barrier (BBB) is a continuous endothelial barrier that is supported by pericytes and astrocytes and regulates the passage of solutes between the bloodstream and the brain. This structure is called the neurovascular unit and serves to protect the brain from blood-borne disease-causing agents and other risk factors. In the past decade, great strides have been made to investigate the neurovascular unit for delivery of chemotherapeutics and for understanding how pathogens can circumvent the barrier, leading to severe and, at times, fatal complications. One such complication is cerebral malaria, in which Plasmodium falciparum-infected red blood cells disrupt the barrier function of the BBB, causing severe brain swelling. Multiple in vitro models of the BBB are available to investigate the mechanisms underlying the pathogenesis of cerebral malaria and other diseases. These range from single-cell monolayer cultures to multicellular BBB organoids and highly complex cerebral organoids. Here, we review the technologies available in malaria research to investigate the interaction between P. falciparum-infected red blood cells and the BBB, and discuss the advantages and disadvantages of each model. Summary: This Review discusses the available in vitro models to investigate the impact of adhesion of Plasmodium falciparum-infected red blood cells on the blood–brain barrier, a process associated with cerebral malaria.
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Affiliation(s)
- Yvonne Adams
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Anja Ramstedt Jensen
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen N, Denmark
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In Vitro Methodologies to Study the Role of Advanced Glycation End Products (AGEs) in Neurodegeneration. Nutrients 2022; 14:nu14020363. [PMID: 35057544 PMCID: PMC8777776 DOI: 10.3390/nu14020363] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 02/07/2023] Open
Abstract
Advanced glycation end products (AGEs) can be present in food or be endogenously produced in biological systems. Their formation has been associated with chronic neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, and amyotrophic lateral sclerosis. The implication of AGEs in neurodegeneration is related to their ability to bind to AGE-specific receptors and the ability of their precursors to induce the so-called “dicarbonyl stress”, resulting in cross-linking and protein damage. However, the mode of action underlying their role in neurodegeneration remains unclear. While some research has been carried out in observational clinical studies, further in vitro studies may help elucidate these underlying modes of action. This review presents and discusses in vitro methodologies used in research on the potential role of AGEs in neuroinflammation and neurodegeneration. The overview reveals the main concepts linking AGEs to neurodegeneration, the current findings, and the available and advisable in vitro models to study their role. Moreover, the major questions regarding the role of AGEs in neurodegenerative diseases and the challenges and discrepancies in the research field are discussed.
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20
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Roy V, Ross JP, Pépin R, Cortez Ghio S, Brodeur A, Touzel Deschênes L, Le-Bel G, Phillips DE, Milot G, Dion PA, Guérin S, Germain L, Berthod F, Auger FA, Rouleau GA, Dupré N, Gros-Louis F. Moyamoya Disease Susceptibility Gene RNF213 Regulates Endothelial Barrier Function. Stroke 2022; 53:1263-1275. [PMID: 34991336 DOI: 10.1161/strokeaha.120.032691] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Variants in the ring finger protein 213 (RNF213) gene are known to be associated with increased predisposition to cerebrovascular diseases development. Genomic studies have identified RNF213 as a major risk factor of Moyamoya disease in East Asian descendants. However, little is known about the RNF213 (ring finger protein 213) biological functions or its associated pathogenic mechanisms underlying Moyamoya disease. METHODS To investigate RNF213 loss-of-function effect in endothelial cell, stable RNF213-deficient human cerebral endothelial cells were generated using the CRISPR-Cas9 genome editing technology. RESULTS In vitro assays, using RNF213 knockout brain endothelial cells, showed clear morphological changes and increased blood-brain barrier permeability. Downregulation and delocalization of essential interendothelial junction proteins involved in the blood-brain barrier maintenance, such as PECAM-1 (platelet endothelial cell adhesion molecule-1), was also observed. Brain endothelial RNF213-deficient cells also showed an abnormal potential to transmigration of leukocytes and secreted high amounts of proinflammatory cytokines. CONCLUSIONS Taken together, these results indicate that RNF213 could be a key regulator of cerebral endothelium integrity, whose disruption could be an early pathological mechanism leading to Moyamoya disease. This study also further reinforces the importance of blood-brain barrier integrity in the development of Moyamoya disease and other RNF213-associated diseases.
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Affiliation(s)
- Vincent Roy
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - Jay P Ross
- McGill University, Montréal, Québec, Canada (J.P.R., D.E.P., P.A.D., G.A.R.)
| | - Rémy Pépin
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - Sergio Cortez Ghio
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - Alyssa Brodeur
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - Lydia Touzel Deschênes
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - Gaëtan Le-Bel
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - Daniel E Phillips
- McGill University, Montréal, Québec, Canada (J.P.R., D.E.P., P.A.D., G.A.R.)
| | - Geneviève Milot
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - Patrick A Dion
- McGill University, Montréal, Québec, Canada (J.P.R., D.E.P., P.A.D., G.A.R.)
| | - Sylvain Guérin
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - Lucie Germain
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - François Berthod
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - François A Auger
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - Guy A Rouleau
- McGill University, Montréal, Québec, Canada (J.P.R., D.E.P., P.A.D., G.A.R.)
| | - Nicolas Dupré
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
| | - François Gros-Louis
- CHU de Québec - Université Laval, Canada (V.R., R.P., S.C.G., A.B., L.T.D., G.L.-B., G.M., S.G., L.G., F.B., F.A.A., N.D., F.G.-L.)
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21
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Spencer BL, Tak U, Mendonça JC, Nagao PE, Niederweis M, Doran KS. A type VII secretion system in Group B Streptococcus mediates cytotoxicity and virulence. PLoS Pathog 2021; 17:e1010121. [PMID: 34871327 PMCID: PMC8675928 DOI: 10.1371/journal.ppat.1010121] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 12/16/2021] [Accepted: 11/16/2021] [Indexed: 12/20/2022] Open
Abstract
Type VII secretion systems (T7SS) have been identified in Actinobacteria and Firmicutes and have been shown to secrete effector proteins with functions in virulence, host toxicity, and/or interbacterial killing in a few genera. Bioinformatic analysis indicates that isolates of Group B Streptococcus (GBS) encode at least four distinct subtypes of T7SS machinery, three of which encode adjacent putative T7SS effectors with WXG and LXG motifs. However, the function of T7SS in GBS pathogenesis is unknown. Here we assessed the role of the most abundant GBS T7SS subtype during GBS pathogenesis. In a murine model of hematogenous meningitis, mice infected with GBS lacking a functional T7SS or lacking the secreted WXG100 effector EsxA exhibited less mortality, lower bacterial burdens in tissues, and decreased inflammation in the brain compared to mice infected with the parental GBS strain. We further showed that this T7SS induces cytotoxicity in brain endothelium and that EsxA contributes to these cytotoxicity phenotypes in a WXG motif-dependent manner. Finally, we determined that EsxA is a pore-forming protein, thus demonstrating the first role for a non-mycobacterial EsxA homolog in pore formation. This work reveals the importance of a T7SS in host–GBS interactions and has implications for T7SS effector function in other Gram-positive bacteria. Group B Streptococcus (GBS) is an important human pathogen that is a leading cause of invasive disease in newborns and certain adult populations, including pregnant women, the elderly, and those with diabetes. During pregnancy, asymptomatically colonizing GBS in the female genital tract can be transmitted to the fetus or newborn and can result in neonatal meningitis upon GBS disruption of the blood-brain barrier (BBB). GBS encodes a type VII secretion system (T7SS), which may allow export of proteins and/or toxins that promote BBB disruption; however, the GBS T7SS has not been studied. Here we show that GBS encodes four types of T7SSs and that the most prevalent subtype is important for GBS meningitis progression, possibly by inducing inflammation and cell death in the brain. We also show that a secreted T7SS effector protein, EsxA, contributes to GBS pathogenesis and can form pores in lipid membranes. This is the first demonstration of EsxA-mediated pore-formation in Gram-positive bacteria.
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Affiliation(s)
- Brady L. Spencer
- University of Colorado Anschutz Medical Campus, Department of Immunology and Microbiology, Aurora, Colorado, United States of America
| | - Uday Tak
- University of Alabama at Birmingham, Department of Microbiology, Birmingham, Alabama, United States of America
| | - Jéssica C. Mendonça
- University of Colorado Anschutz Medical Campus, Department of Immunology and Microbiology, Aurora, Colorado, United States of America
- Rio de Janeiro State University, Roberto Alcântara Gomes Biology Institute, Rio de Janeiro, RJ, Brazil
| | - Prescilla E. Nagao
- Rio de Janeiro State University, Roberto Alcântara Gomes Biology Institute, Rio de Janeiro, RJ, Brazil
| | - Michael Niederweis
- University of Alabama at Birmingham, Department of Microbiology, Birmingham, Alabama, United States of America
| | - Kelly S. Doran
- University of Colorado Anschutz Medical Campus, Department of Immunology and Microbiology, Aurora, Colorado, United States of America
- * E-mail:
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22
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Zoladek J, Legros V, Jeannin P, Chazal M, Pardigon N, Ceccaldi PE, Gessain A, Jouvenet N, Afonso PV. Zika Virus Requires the Expression of Claudin-7 for Optimal Replication in Human Endothelial Cells. Front Microbiol 2021; 12:746589. [PMID: 34616388 PMCID: PMC8488266 DOI: 10.3389/fmicb.2021.746589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 08/23/2021] [Indexed: 01/31/2023] Open
Abstract
Zika virus (ZIKV) infection has been associated with a series of neurological pathologies. In patients with ZIKV-induced neurological disorders, the virus is detectable in the central nervous system. Thus, ZIKV is capable of neuroinvasion, presumably through infection of the endothelial cells that constitute the blood-brain barrier (BBB). We demonstrate that susceptibility of BBB endothelial cells to ZIKV infection is modulated by the expression of tight-junction protein claudin-7 (CLDN7). Downregulation of CLDN7 reduced viral RNA yield, viral protein production, and release of infectious viral particles in several endothelial cell types, but not in epithelial cells, indicating that CLDN7 implication in viral infection is cell-type specific. The proviral activity of CLDN7 in endothelial cells is ZIKV-specific since related flaviviruses were not affected by CLDN7 downregulation. Together, our data suggest that CLDN7 facilitates ZIKV infection in endothelial cells at a post-internalization stage and prior to RNA production. Our work contributes to a better understanding of the mechanisms exploited by ZIKV to efficiently infect and replicate in endothelial cells and thus of its ability to cross the BBB.
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Affiliation(s)
- Jim Zoladek
- Unité Épidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Centre National de la Recherche Scientifique UMR 3569, Université de Paris, Paris, France
| | - Vincent Legros
- Unité Épidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Centre National de la Recherche Scientifique UMR 3569, Université de Paris, Paris, France.,VetAgro Sup, Centre International de Recherche en Infectiologie (CIRI), Lyon, France
| | - Patricia Jeannin
- Unité Épidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Centre National de la Recherche Scientifique UMR 3569, Université de Paris, Paris, France
| | - Maxime Chazal
- Unité Signalisation Antivirale, Institut Pasteur, Centre National de la Recherche Scientifique UMR 3569, Paris, France
| | - Nathalie Pardigon
- Groupe Arbovirus, Unité Environnement et Risques Infectieux, Institut Pasteur, Paris, France
| | - Pierre-Emmanuel Ceccaldi
- Unité Épidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Centre National de la Recherche Scientifique UMR 3569, Université de Paris, Paris, France
| | - Antoine Gessain
- Unité Épidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Centre National de la Recherche Scientifique UMR 3569, Université de Paris, Paris, France
| | - Nolwenn Jouvenet
- Unité Signalisation Antivirale, Institut Pasteur, Centre National de la Recherche Scientifique UMR 3569, Paris, France
| | - Philippe V Afonso
- Unité Épidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Centre National de la Recherche Scientifique UMR 3569, Université de Paris, Paris, France
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23
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Kim J, Lee KT, Lee JS, Shin J, Cui B, Yang K, Choi YS, Choi N, Lee SH, Lee JH, Bahn YS, Cho SW. Fungal brain infection modelled in a human-neurovascular-unit-on-a-chip with a functional blood-brain barrier. Nat Biomed Eng 2021; 5:830-846. [PMID: 34127820 DOI: 10.1038/s41551-021-00743-8] [Citation(s) in RCA: 73] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 04/30/2021] [Indexed: 02/05/2023]
Abstract
The neurovascular unit, which consists of vascular cells surrounded by astrocytic end-feet and neurons, controls cerebral blood flow and the permeability of the blood-brain barrier (BBB) to maintain homeostasis in the neuronal milieu. Studying how some pathogens and drugs can penetrate the human BBB and disrupt neuronal homeostasis requires in vitro microphysiological models of the neurovascular unit. Here we show that the neurotropism of Cryptococcus neoformans-the most common pathogen causing fungal meningitis-and its ability to penetrate the BBB can be modelled by the co-culture of human neural stem cells, brain microvascular endothelial cells and brain vascular pericytes in a human-neurovascular-unit-on-a-chip maintained by a stepwise gravity-driven unidirectional flow and recapitulating the structural and functional features of the BBB. We found that the pathogen forms clusters of cells that penetrate the BBB without altering tight junctions, suggesting a transcytosis-mediated mechanism. The neurovascular-unit-on-a-chip may facilitate the study of the mechanisms of brain infection by pathogens, and the development of drugs for a range of brain diseases.
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Affiliation(s)
- Jin Kim
- Department of Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Kyung-Tae Lee
- Department of Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Jong Seung Lee
- Department of Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Jisoo Shin
- Department of Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Baofang Cui
- Department of Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Kisuk Yang
- Department of Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Yi Sun Choi
- Department of Biotechnology, Yonsei University, Seoul, Republic of Korea
| | - Nakwon Choi
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea.,KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, Republic of Korea.,Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology (UST), Seoul, Republic of Korea
| | - Soo Hyun Lee
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Jae-Hyun Lee
- Institute for Basic Science (IBS), Center for Nanomedicine, Seoul, Republic of Korea.,Graduate Program of Nano Biomedical Engineering (NanoBME), Advanced Science Institute, Yonsei University, Seoul, Republic of Korea
| | - Yong-Sun Bahn
- Department of Biotechnology, Yonsei University, Seoul, Republic of Korea.
| | - Seung-Woo Cho
- Department of Biotechnology, Yonsei University, Seoul, Republic of Korea. .,Institute for Basic Science (IBS), Center for Nanomedicine, Seoul, Republic of Korea. .,Graduate Program of Nano Biomedical Engineering (NanoBME), Advanced Science Institute, Yonsei University, Seoul, Republic of Korea.
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24
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Ray RM, Hansen AH, Taskova M, Jandl B, Hansen J, Soemardy C, Morris KV, Astakhova K. Enhanced target cell specificity and uptake of lipid nanoparticles using RNA aptamers and peptides. Beilstein J Org Chem 2021; 17:891-907. [PMID: 33981364 PMCID: PMC8093553 DOI: 10.3762/bjoc.17.75] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 04/09/2021] [Indexed: 01/28/2023] Open
Abstract
Lipid nanoparticles (LNPs) constitute a facile and scalable approach for delivery of payloads to human cells. LNPs are relatively immunologically inert and can be produced in a cost effective and scalable manner. However, targeting and delivery of LNPs across the blood–brain barrier (BBB) has proven challenging. In an effort to target LNPs composed of an ionizable cationic lipid (DLin-MC3-DMA), cholesterol, the phospholipid 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), and 1,2-dimyristoyl-rac-glycero-3-methoxypolyethylene glycol-2000 (DMG-PEG 2000) to particular cell types, as well as to generate LNPs that can cross the BBB, we developed and assessed two approaches. The first was centered on the BBB-penetrating trans-activator of transcription (Tat) peptide or the peptide T7, and the other on RNA aptamers targeted to glycoprotein gp160 from human immunodeficiency virus (HIV) or C-C chemokine receptor type 5 (CCR5), a HIV-1 coreceptor. We report herein a CCR5-selective RNA aptamer that acts to facilitate entry through a simplified BBB model and that drives the uptake of LNPs into CCR5-expressing cells, while the gp160 aptamer did not. We further observed that the addition of cell-penetrating peptides, Tat and T7, did not increase BBB penetration above the aptamer-loaded LNPs alone. Moreover, we found that these targeted LNPs exhibit low immunogenic and low toxic profiles and that targeted LNPs can traverse the BBB to potentially deliver drugs into the target tissue. This approach highlights the usefulness of aptamer-loaded LNPs to increase target cell specificity and potentially deliverability of central-nervous-system-active RNAi therapeutics across the BBB.
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Affiliation(s)
- Roslyn M Ray
- Center for Gene Therapy, Beckman Research Institute, City of Hope, Duarte, CA, United States of America
| | | | - Maria Taskova
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Bernhard Jandl
- Institute of Biological Chemistry, Faculty of Chemistry, University of Vienna, 1090 Vienna, Austria
| | - Jonas Hansen
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
| | - Citra Soemardy
- Center for Gene Therapy, Beckman Research Institute, City of Hope, Duarte, CA, United States of America
| | - Kevin V Morris
- Center for Gene Therapy, Beckman Research Institute, City of Hope, Duarte, CA, United States of America.,School of Medical Sciences, Griffith University, Gold Coast, Australia 4222.,Menzies Health Institute Queensland, Griffith University, Gold Coast, QLD 4222, Australia
| | - Kira Astakhova
- Department of Chemistry, Technical University of Denmark, Lyngby, Denmark
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25
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Chen Y, Li C, Sun D, Strickland AB, Liu G, Shi M. Quantitative analysis reveals internalisation of Cryptococcus neoformans by brain endothelial cells in vivo. Cell Microbiol 2021; 23:e13330. [PMID: 33745221 DOI: 10.1111/cmi.13330] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 03/16/2021] [Accepted: 03/17/2021] [Indexed: 12/12/2022]
Abstract
Migration of Cryptococcus neoformans from the blood to the brain parenchyma is crucial to cause fatal meningoencephalitis. Although mechanisms involved in brain migration of C. neoformans have been widely studied in vitro, less is known about how the fungus crosses the blood-brain barrier (BBB) in vivo. This is in part because of the lack of an approach to quantitatively analyse the dynamics of fungal transmigration into the brain across the BBB in vivo. In this study, we report a novel approach to quantitatively analyse the interactions between C. neoformans and brain endothelial cells in a mouse model using flow cytometry. Using this system, we show that C. neoformans was internalised by brain endothelial cells in vivo and that mice infected with acapsular or heat-killed C. neoformans yeast cells displayed a lower frequency of brain endothelial cells containing the yeast cell compared to mice infected with wild-type or viable yeast cells, respectively. We further demonstrate that brain endothelial cells were invaded by serotype A strain (H99 strain) at a higher rate compared to serotype D strain (52D strain). Our experiments established that internalisation of C. neoformans by brain endothelial cells occurred in vivo and offered a powerful approach to quantitatively analyse fungal migration into the brain.
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Affiliation(s)
- Yanli Chen
- Division of Immunology, Virginia-Maryland College of Veterinary Medicine and Maryland Pathogen Research Institute, University of Maryland, College Park, Maryland, USA
| | - Chang Li
- Division of Immunology, Virginia-Maryland College of Veterinary Medicine and Maryland Pathogen Research Institute, University of Maryland, College Park, Maryland, USA
| | - Donglei Sun
- Division of Immunology, Virginia-Maryland College of Veterinary Medicine and Maryland Pathogen Research Institute, University of Maryland, College Park, Maryland, USA
| | - Ashley B Strickland
- Division of Immunology, Virginia-Maryland College of Veterinary Medicine and Maryland Pathogen Research Institute, University of Maryland, College Park, Maryland, USA
| | - Gongguan Liu
- Division of Immunology, Virginia-Maryland College of Veterinary Medicine and Maryland Pathogen Research Institute, University of Maryland, College Park, Maryland, USA
| | - Meiqing Shi
- Division of Immunology, Virginia-Maryland College of Veterinary Medicine and Maryland Pathogen Research Institute, University of Maryland, College Park, Maryland, USA
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26
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Zhao J, Li K, Wang Y, Li D, Wang Q, Xie S, Wang J, Zuo Z. Enhanced anti-amnestic effect of donepezil by Ginkgo biloba extract (EGb 761) via further improvement in pro-cholinergic and antioxidative activities. JOURNAL OF ETHNOPHARMACOLOGY 2021; 269:113711. [PMID: 33352242 DOI: 10.1016/j.jep.2020.113711] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 11/27/2020] [Accepted: 12/18/2020] [Indexed: 06/12/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE EGb 761 is a standardized dry extract of Ginkgo biloba L. leaves traditionally used by Eastern Asia and has been associated with beneficial effects on neurodegeneration disorders, including Alzheimer's disease. AIM OF THE STUDY Since beneficial interactions between EGb 761 and donepezil have been observed in previous clinical studies, the current study was proposed aiming to further explore related mechanisms from both pharmacokinetics and pharmacodynamics aspects. MATERIALS AND METHODS Pharmacodynamic interactions were studied in scopolamine-induced cognitive impairment rats received two-weeks treatment of vehicle, EGb 761 and/or donepezil by the Morris water maze test and ex vivo evaluation of biomarkers of cholinergic transmission and oxidative stress in rat brain. In the meantime, pharmacokinetic profiles of donepezil and bilobalide were obtained and compared among all treatment groups. In addition, impact of the bioavailable EGb 761 components on donepezil brain penetration was evaluated with the hCMEC/D3 cell monolayer model. RESULTS Scopolamine-induced rats with co-treatment of EGb 761 and donepezil had significantly improved cognitive function in the Morris water maze test with increased brain levels of superoxide dismutase and decreased brain levels of acetylcholinesterase and malondialdehyde than that with treatment of only EGb 761 or donepezil. Despite such beneficial pharmacodynamics outcomes, the two-week co-treatment of EGb 761 and donepezil did not alter the plasma pharmacokinetics and brain uptake of donepezil or bilobalide, which was further verified in the hCMEC/D3 monolayer model. CONCLUSION Co-administration of EGb 761 and donepezil exerted better anti-amnestic effect via further enhanced pro-cholinergic and antioxidative effects of EGb 761 or donepezil in scopolamine-induced cognitive impairment rat without alteration in their systemic/brain exposure.
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Affiliation(s)
- Jiajia Zhao
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
| | - Kun Li
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, 510405, People's Republic of China.
| | - Yingying Wang
- Department of Pharmaceutics, School of Pharmacy, Fudan University, Shanghai, 201203, People's Republic of China.
| | - Dan Li
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
| | - Qianwen Wang
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
| | - Shengsheng Xie
- Department of Pharmaceutics, School of Pharmacy, Fudan University, Shanghai, 201203, People's Republic of China.
| | - Jianxin Wang
- Department of Pharmaceutics, School of Pharmacy, Fudan University, Shanghai, 201203, People's Republic of China; Institute of Integrated Chinese and Western Medicine, Fudan University, Shanghai, 200040, People's Republic of China.
| | - Zhong Zuo
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong; Department of Pharmaceutics, School of Pharmacy, Fudan University, Shanghai, 201203, People's Republic of China; Institute of Integrated Chinese and Western Medicine, Fudan University, Shanghai, 200040, People's Republic of China.
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27
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Strickland AB, Shi M. Mechanisms of fungal dissemination. Cell Mol Life Sci 2021; 78:3219-3238. [PMID: 33449153 PMCID: PMC8044058 DOI: 10.1007/s00018-020-03736-z] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 11/23/2020] [Accepted: 12/08/2020] [Indexed: 12/13/2022]
Abstract
Fungal infections are an increasing threat to global public health. There are more than six million fungal species worldwide, but less than 1% are known to infect humans. Most of these fungal infections are superficial, affecting the hair, skin and nails, but some species are capable of causing life-threatening diseases. The most common of these include Cryptococcus neoformans, Aspergillus fumigatus and Candida albicans. These fungi are typically innocuous and even constitute a part of the human microbiome, but if these pathogens disseminate throughout the body, they can cause fatal infections which account for more than one million deaths worldwide each year. Thus, systemic dissemination of fungi is a critical step in the development of these deadly infections. In this review, we discuss our current understanding of how fungi disseminate from the initial infection sites to the bloodstream, how immune cells eliminate fungi from circulation and how fungi leave the blood and enter distant organs, highlighting some recent advances and offering some perspectives on future directions.
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Affiliation(s)
- Ashley B Strickland
- Division of Immunology, Virginia-Maryland College of Veterinary Medicine and Maryland Pathogen Research Institute, University of Maryland, College Park, MD, USA.
| | - Meiqing Shi
- Division of Immunology, Virginia-Maryland College of Veterinary Medicine and Maryland Pathogen Research Institute, University of Maryland, College Park, MD, USA.
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28
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Nozohouri S, Noorani B, Al-Ahmad A, Abbruscato TJ. Estimating Brain Permeability Using In Vitro Blood-Brain Barrier Models. Methods Mol Biol 2021; 2367:47-72. [PMID: 32789777 DOI: 10.1007/7651_2020_311] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The blood-brain barrier (BBB) is a vital biological interface that regulates transfer of different molecules between blood and brain and, therefore, maintains the homeostatic environment of the CNS. In order to perform high-throughput screening of therapeutics in drug discovery, specific properties of the BBB are investigated within in vitro BBB platforms. In this chapter, we detail the process and steps for the iPSC to BMEC and astrocyte differentiation as well as TEER and permeability measurement in Transwell platform of in vitro BBB model. Also, advanced microfluidic iPSCs-derived BMECs on chip and permeability measurement within this model have been elucidated.
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Affiliation(s)
- Saeideh Nozohouri
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA
- Center for Blood-Brain Barrier Research, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA
| | - Behnam Noorani
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA
- Center for Blood-Brain Barrier Research, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA
| | - Abraham Al-Ahmad
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA
- Center for Blood-Brain Barrier Research, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA
| | - Thomas J Abbruscato
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA.
- Center for Blood-Brain Barrier Research, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA.
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Alabsi W, Al-Obeidi FA, Polt R, Mansour HM. Organic Solution Advanced Spray-Dried Microparticulate/Nanoparticulate Dry Powders of Lactomorphin for Respiratory Delivery: Physicochemical Characterization, In Vitro Aerosol Dispersion, and Cellular Studies. Pharmaceutics 2020; 13:E26. [PMID: 33375607 PMCID: PMC7824383 DOI: 10.3390/pharmaceutics13010026] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 12/14/2020] [Accepted: 12/17/2020] [Indexed: 12/28/2022] Open
Abstract
The purpose of this study was to formulate Lactomorphin (MMP2200) in its pure state as spray-dried(SD) powders, and with the excipient Trehalose as co-spray-dried(co-SD) powders; for intranasal and deep lung administration with Dry Powder Inhalers (DPI). Lactomorphin is a glycopeptide which was developed for the control of moderate to severe pain. Particles were rationally designed and produced by advanced spray drying particle engineering in a closed mode from a dilute organic solution. Comprehensive physicochemical characterization using different analytical techniques was carried out to analyze the particle size, particle morphology, particle surface morphology, solid-state transitions, crystallinity/non-crystallinity, and residual water content. The particle chemical composition was confirmed using attenuated total reflectance-Fourier-transform infrared (ATR-FTIR), and Confocal Raman Microscopy (CRM) confirmed the particles' chemical homogeneity. The solubility and Partition coefficient (LogP) of Lactomorphin were determined by the analytical and computational methodology and revealed the hydrophilicity of Lactomorphin. A thermal degradation study was performed by exposing samples of solid-state Lactomorphin to a high temperature (62 °C) combined with zero relative humidity (RH) and to a high temperature (62 °C) combined with a high RH (75%) to evaluate the stability of Lactomorphin under these two different conditions. The solid-state processed particles exhibited excellent aerosol dispersion performance with an FDA-approved human DPI device to reach lower airways. The cell viability resazurin assay showed that Lactomorphin is safe up to 1000 μg/mL on nasal epithelium cells, lung cells, endothelial, and astrocyte brain cells.
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Affiliation(s)
- Wafaa Alabsi
- Department of Chemistry & Biochemistry, The University of Arizona, Tucson, AZ 85721, USA; (W.A.); (F.A.A.-O.); (R.P.)
- College of Pharmacy, Skaggs Pharmaceutical Sciences Center, The University of Arizona, Tucson, AZ 85721, USA
| | - Fahad A. Al-Obeidi
- Department of Chemistry & Biochemistry, The University of Arizona, Tucson, AZ 85721, USA; (W.A.); (F.A.A.-O.); (R.P.)
| | - Robin Polt
- Department of Chemistry & Biochemistry, The University of Arizona, Tucson, AZ 85721, USA; (W.A.); (F.A.A.-O.); (R.P.)
| | - Heidi M. Mansour
- College of Pharmacy, Skaggs Pharmaceutical Sciences Center, The University of Arizona, Tucson, AZ 85721, USA
- College of Medicine, Division of Translational & Regenerative Medicine, The University of Arizona, Tucson, AZ 85721, USA
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Genome-wide functional analysis of phosphatases in the pathogenic fungus Cryptococcus neoformans. Nat Commun 2020; 11:4212. [PMID: 32839469 PMCID: PMC7445287 DOI: 10.1038/s41467-020-18028-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 07/30/2020] [Indexed: 12/13/2022] Open
Abstract
Phosphatases, together with kinases and transcription factors, are key components in cellular signalling networks. Here, we present a systematic functional analysis of the phosphatases in Cryptococcus neoformans, a fungal pathogen that causes life-threatening fungal meningoencephalitis. We analyse 230 signature-tagged mutant strains for 114 putative phosphatases under 30 distinct in vitro growth conditions, revealing at least one function for 60 of these proteins. Large-scale virulence and infectivity assays using insect and mouse models indicate roles in pathogenicity for 31 phosphatases involved in various processes such as thermotolerance, melanin and capsule production, stress responses, O-mannosylation, or retromer function. Notably, phosphatases Xpp1, Ssu72, Siw14, and Sit4 promote blood-brain barrier adhesion and crossing by C. neoformans. Together with our previous systematic studies of transcription factors and kinases, our results provide comprehensive insight into the pathobiological signalling circuitry of C. neoformans. Phosphatases are key components in cellular signalling networks. Here, the authors present a systematic functional analysis of phosphatases of the fungal pathogen Cryptococcus neoformans, revealing roles in virulence, stress responses, O-mannosylation, retromer function and other processes.
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An Antivirulence Approach for Preventing Cryptococcus neoformans from Crossing the Blood-Brain Barrier via Novel Natural Product Inhibitors of a Fungal Metalloprotease. mBio 2020; 11:mBio.01249-20. [PMID: 32694141 PMCID: PMC7374060 DOI: 10.1128/mbio.01249-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Fungal infections like cryptococcal meningitis are difficult to resolve because of the limited therapies available. The small arsenal of antifungal drugs reflect the difficulty in finding available targets in fungi because like mammalian cells, fungi are eukaryotes. The limited efficacy, toxicity, and rising resistance of antifungals contribute to the high morbidity and mortality of fungal infections and further underscore the dire but unmet need for new antifungal drugs. The traditional approach in antifungal drug development has been to target fungal growth, but an attractive alternative is to target mechanisms of pathogenesis. An important attribute of Cryptococcus neoformans (Cn) pathogenesis is its ability to enter the central nervous system. Here, we describe a large-scale screen that identified three natural products that prevented Cn from crossing the blood-brain barrier by inhibiting the virulence factor Mpr1 without affecting the growth of Cn. We propose that compounds identified here could be further developed as antivirulence therapy that would be administered preemptively or serve as a prophylactic in patients at high risk for developing cryptococcal meningitis. Cryptococcus neoformans (Cn) is the leading cause of fungal meningitis, a deadly disease with limited therapeutic options. Dissemination to the central nervous system hinges on the ability of Cn to breach the blood-brain barrier (BBB) and is considered an attribute of Cn virulence. Targeting virulence instead of growth for antifungal drug development has not been fully exploited despite the benefits of this approach. Mpr1 is a secreted fungal metalloprotease not required for fungal growth, but rather, it functions as a virulence factor by facilitating Cn migration across the BBB. This central role for Mpr1, its extracellular location, and lack of expression in mammalian cells make Mpr1 a high-value target for an antivirulence approach aimed at developing therapeutics for cryptococcal meningitis. To test this notion, we devised a large-scale screen to identify compounds that prohibited Cn from crossing the BBB by selectively blocking Mpr1 proteolytic activity, without inhibiting the growth of Cn. A phytochemical natural product-derived library was screened to identify new molecular scaffolds of prototypes unique to a Cn microecosystem. Of the 240 pure natural products examined, 3 lead compounds, abietic acid, diosgenin, and lupinine inhibited Mpr1 proteolytic activity with 50% inhibitory concentration (IC50) values of <10 μM, displayed little to no mammalian cell toxicity, and did not affect Cn growth. Notably, the lead compounds blocked Cn from crossing the BBB, without damaging the barrier integrity, suggesting the bioactive molecules had no off-target effects. We propose that these new drug scaffolds are promising candidates for the development of antivirulence therapy against cryptococcal meningitis.
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Fungal kinases and transcription factors regulating brain infection in Cryptococcus neoformans. Nat Commun 2020; 11:1521. [PMID: 32251295 PMCID: PMC7090016 DOI: 10.1038/s41467-020-15329-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 03/03/2020] [Indexed: 12/19/2022] Open
Abstract
Cryptococcus neoformans causes fatal fungal meningoencephalitis. Here, we study the roles played by fungal kinases and transcription factors (TFs) in blood-brain barrier (BBB) crossing and brain infection in mice. We use a brain infectivity assay to screen signature-tagged mutagenesis (STM)-based libraries of mutants defective in kinases and TFs, generated in the C. neoformans H99 strain. We also monitor in vivo transcription profiles of kinases and TFs during host infection using NanoString technology. These analyses identify signalling components involved in BBB adhesion and crossing, or survival in the brain parenchyma. The TFs Pdr802, Hob1, and Sre1 are required for infection under all the conditions tested here. Hob1 controls the expression of several factors involved in brain infection, including inositol transporters, a metalloprotease, PDR802, and SRE1. However, Hob1 is dispensable for most cellular functions in Cryptococcus deuterogattii R265, a strain that does not target the brain during infection. Our results indicate that Hob1 is a master regulator of brain infectivity in C. neoformans. Cryptococcus neoformans causes fatal fungal meningoencephalitis. Here, the authors identify fungal kinases and transcription factors involved in blood-brain barrier crossing and brain infection in mice.
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Chiu CF, Chu LW, Liao IC, Simanjuntak Y, Lin YL, Juan CC, Ping YH. The Mechanism of the Zika Virus Crossing the Placental Barrier and the Blood-Brain Barrier. Front Microbiol 2020; 11:214. [PMID: 32153526 PMCID: PMC7044130 DOI: 10.3389/fmicb.2020.00214] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 01/30/2020] [Indexed: 12/17/2022] Open
Abstract
Zika virus (ZIKV) infection causes severe neurological symptoms in adults and fetal microcephaly and the virus is detected in the brain of microcephaly and meningoencephalitis patient. However, the mechanism of ZIKV crossing the physiological barrier to the central nervous systems (CNS) remains elusive. The placental barrier and the blood brain barrier (BBB) protect the fetus from pathogens and ensure healthy brain development during pregnancy. In this study, we used human placenta trophoblasts cells (JEG-3) and human brain-derived endothelial cells (hCMEC/D3) as in vitro models of the physiological barriers. Results showed that ZIKV could infect JEG-3 cells effectively and reduce the amounts of ZO-1 and occludin between adjacent cells by the proteasomal degradation pathway, suggesting that the permeability of the barrier differentially changed in response to ZIKV infection, allowing the virus particle to cross the host barrier. In contrast, ZIKV could infect hCMEC/D3 cells without disrupting the BBB barrier permeability and tight junction protein expression. Although no disruption to the BBB was observed during ZIKV infection, ZIKV particles were released on the basal side of the BBB model and infected underlying cells. In addition, we observed that fluorescence-labeled ZIKV particles could cross the in vitro placenta barrier and BBB model by transcytosis and the action of transcytosis could be blocked by either low temperature or pharmacological inhibitors of endocytosis. In summary, the ZIKV uses a cell-type specific paracellular pathway to cross the placenta monolayer barrier by disrupting cellular tight junction. In addition, the ZIKV can also cross both the placenta barrier and the BBB by transcytosis. Our study provided new insights into on the mechanism of the cellular barrier penetration of ZIKV particles.
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Affiliation(s)
- Chi-Fen Chiu
- Department and Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan
| | - Li-Wei Chu
- Department and Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan
| | - I-Chen Liao
- Department and Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan
| | - Yogy Simanjuntak
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yi-Ling Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Chi-Chang Juan
- Department and Institute of Physiology, National Yang-Ming University, Taipei, Taiwan
| | - Yueh-Hsin Ping
- Department and Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan
- Institute of Biophotonics, National Yang-Ming University, Taipei, Taiwan
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Aaron PA, Gelli A. Harnessing the Activity of the Fungal Metalloprotease, Mpr1, To Promote Crossing of Nanocarriers through the Blood-Brain Barrier. ACS Infect Dis 2020; 6:138-149. [PMID: 31820926 DOI: 10.1021/acsinfecdis.9b00348] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Cryptococcus neoformans (Cn) is the leading cause of fungal meningitis primarily in immunosuppressed patients. Cn invades the central nervous system by overcoming the highly restricted blood-brain barrier (BBB). We previously determined that a secreted fungal metalloprotease, Mpr1, that also confers crossing ability to yeast upon CnMPR1 expression in Saccharomyces cerevisiae is central to this process. This led us to question whether Mpr1 could be engineered to function as part of a nanocarrier delivery vehicle. Here, a eukaryotic expression system produced proteolytically active Mpr1 recombinant protein that was successfully conjugated to functionalized quantum dot (QD) nanoparticles and readily internalized by brain microvascular endothelial cells. An in vitro BBB model showed QD-Mpr1 crossed the BBB significantly better than mock QD, and QD-Mpr1 did not damage BBB integrity. Internalization of QD-Mpr1 occurred by membrane invaginations and endocytic pits typical of receptor-mediated endocytosis involving clathrin-coated entry points. This study substantiates the notion that fungal mechanisms of BBB entry may be harnessed for new drug delivery platform technologies.
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Affiliation(s)
- Phylicia A. Aaron
- Department of Pharmacology, School of Medicine, University of California, 3503 Genome and Biomedical Sciences Facility, 451 Health Sciences Drive, Davis, California 95616, United States
| | - Angie Gelli
- Department of Pharmacology, School of Medicine, University of California, 3503 Genome and Biomedical Sciences Facility, 451 Health Sciences Drive, Davis, California 95616, United States
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Abstract
Macrophages are well known for their phagocytic activity and their role in innate immune responses. Macrophages eat non-self particles, via a variety of mechanisms, and typically break down internalized cargo into small macromolecules. However, some pathogenic agents have the ability to evade this endosomal degradation through a nonlytic exocytosis process termed vomocytosis. Macrophages are well known for their phagocytic activity and their role in innate immune responses. Macrophages eat non-self particles, via a variety of mechanisms, and typically break down internalized cargo into small macromolecules. However, some pathogenic agents have the ability to evade this endosomal degradation through a nonlytic exocytosis process termed vomocytosis. This phenomenon has been most often studied for Cryptococcus neoformans, a yeast that causes roughly 180,000 deaths per year, primarily in immunocompromised (e.g., human immunodeficiency virus [HIV]) patients. Existing dogma purports that vomocytosis involves distinctive cellular pathways and intracellular physicochemical cues in the host cell during phagosomal maturation. Moreover, it has been observed that the immunological state of the individual and macrophage phenotype affect vomocytosis outcomes. Here we compile the current knowledge on the factors (with respect to the phagocytic cell) that promote vomocytosis of C. neoformans from macrophages.
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Laksitorini MD, Yathindranath V, Xiong W, Hombach-Klonisch S, Miller DW. Modulation of Wnt/β-catenin signaling promotes blood-brain barrier phenotype in cultured brain endothelial cells. Sci Rep 2019; 9:19718. [PMID: 31873116 PMCID: PMC6928218 DOI: 10.1038/s41598-019-56075-w] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 11/24/2019] [Indexed: 12/16/2022] Open
Abstract
Wnt/β-catenin signaling is important for blood-brain barrier (BBB) development and is implicated in BBB breakdown under various pathophysiological conditions. In the present study, a comprehensive characterization of the relevant genes, transport and permeability processes influenced by both the autocrine and external activation of Wnt signaling in human brain endothelial cells was examined using hCMEC/D3 culture model. The hCMEC/D3 expressed a full complement of Wnt ligands and receptors. Preventing Wnt ligand release from hCMEC/D3 produced minimal changes in brain endothelial function, while inhibition of intrinsic/autocrine Wnt/β-catenin activity through blocking β-catenin binding to Wnt transcription factor caused more modest changes. In contrast, activation of Wnt signaling using exogenous Wnt ligand (Wnt3a) or LiCl (GSK3 inhibitor) improved the BBB phenotypes of the hCMEC/D3 culture model, resulting in reduced paracellular permeability, and increased P-glycoprotein (P-gp) and breast cancer resistance associated protein (BCRP) efflux transporter activity. Further, Wnt3a reduced plasmalemma vesicle associated protein (PLVAP) and vesicular transport activity in hCMEC/D3. Our data suggest that this in vitro model of the BBB has a more robust response to exogenous activation of Wnt/β-catenin signaling compared to autocrine activation, suggesting that BBB regulation may be more dependent on external activation of Wnt signaling within the brain microvasculature.
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Affiliation(s)
- Marlyn D Laksitorini
- Department of Pharmacology and Theurapetics, Max Rady College of Medicine, University of Manitoba, Winnipeg, R3E 0T6, Canada
- Department of Pharmaceutics, Faculty of Pharmacy, Gadjah Mada University, Yogyakarta, 55281, Indonesia
| | - Vinith Yathindranath
- Department of Pharmacology and Theurapetics, Max Rady College of Medicine, University of Manitoba, Winnipeg, R3E 0T6, Canada
| | - Wei Xiong
- Department of Pharmacology and Theurapetics, Max Rady College of Medicine, University of Manitoba, Winnipeg, R3E 0T6, Canada
| | - Sabine Hombach-Klonisch
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, University of Manitoba, Winnipeg, R3E 0J9, Canada
| | - Donald W Miller
- Department of Pharmacology and Theurapetics, Max Rady College of Medicine, University of Manitoba, Winnipeg, R3E 0T6, Canada.
- Kleysen Institute of Advanced Medicine, Health Sciences Center, Winnipeg, Manitoba, R3E 0T6, Canada.
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Gomez-Zepeda D, Taghi M, Scherrmann JM, Decleves X, Menet MC. ABC Transporters at the Blood-Brain Interfaces, Their Study Models, and Drug Delivery Implications in Gliomas. Pharmaceutics 2019; 12:pharmaceutics12010020. [PMID: 31878061 PMCID: PMC7022905 DOI: 10.3390/pharmaceutics12010020] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 12/13/2019] [Accepted: 12/20/2019] [Indexed: 12/22/2022] Open
Abstract
Drug delivery into the brain is regulated by the blood-brain interfaces. The blood-brain barrier (BBB), the blood-cerebrospinal fluid barrier (BCSFB), and the blood-arachnoid barrier (BAB) regulate the exchange of substances between the blood and brain parenchyma. These selective barriers present a high impermeability to most substances, with the selective transport of nutrients and transporters preventing the entry and accumulation of possibly toxic molecules, comprising many therapeutic drugs. Transporters of the ATP-binding cassette (ABC) superfamily have an important role in drug delivery, because they extrude a broad molecular diversity of xenobiotics, including several anticancer drugs, preventing their entry into the brain. Gliomas are the most common primary tumors diagnosed in adults, which are often characterized by a poor prognosis, notably in the case of high-grade gliomas. Therapeutic treatments frequently fail due to the difficulty of delivering drugs through the brain barriers, adding to diverse mechanisms developed by the cancer, including the overexpression or expression de novo of ABC transporters in tumoral cells and/or in the endothelial cells forming the blood-brain tumor barrier (BBTB). Many models have been developed to study the phenotype, molecular characteristics, and function of the blood-brain interfaces as well as to evaluate drug permeability into the brain. These include in vitro, in vivo, and in silico models, which together can help us to better understand their implication in drug resistance and to develop new therapeutics or delivery strategies to improve the treatment of pathologies of the central nervous system (CNS). In this review, we present the principal characteristics of the blood-brain interfaces; then, we focus on the ABC transporters present on them and their implication in drug delivery; next, we present some of the most important models used for the study of drug transport; finally, we summarize the implication of ABC transporters in glioma and the BBTB in drug resistance and the strategies to improve the delivery of CNS anticancer drugs.
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Affiliation(s)
- David Gomez-Zepeda
- Inserm, UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, 75006 Paris, France; (M.T.); (J.-M.S.); (X.D.)
- Sorbonne Paris Cité, Université Paris Descartes, 75006 Paris, France
- Sorbonne Paris Cité, Université Paris Diderot, 75013 Paris, France
- Correspondence: (D.G.-Z.); (M.-C.M.)
| | - Méryam Taghi
- Inserm, UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, 75006 Paris, France; (M.T.); (J.-M.S.); (X.D.)
- Sorbonne Paris Cité, Université Paris Descartes, 75006 Paris, France
- Sorbonne Paris Cité, Université Paris Diderot, 75013 Paris, France
| | - Jean-Michel Scherrmann
- Inserm, UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, 75006 Paris, France; (M.T.); (J.-M.S.); (X.D.)
- Sorbonne Paris Cité, Université Paris Descartes, 75006 Paris, France
- Sorbonne Paris Cité, Université Paris Diderot, 75013 Paris, France
| | - Xavier Decleves
- Inserm, UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, 75006 Paris, France; (M.T.); (J.-M.S.); (X.D.)
- Sorbonne Paris Cité, Université Paris Descartes, 75006 Paris, France
- Sorbonne Paris Cité, Université Paris Diderot, 75013 Paris, France
- UF Biologie du médicament et toxicologie, Hôpital Cochin, AP HP, 75006 Paris, France
| | - Marie-Claude Menet
- Inserm, UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, 75006 Paris, France; (M.T.); (J.-M.S.); (X.D.)
- Sorbonne Paris Cité, Université Paris Descartes, 75006 Paris, France
- Sorbonne Paris Cité, Université Paris Diderot, 75013 Paris, France
- UF Hormonologie adulte, Hôpital Cochin, AP HP, 75006 Paris, France
- Correspondence: (D.G.-Z.); (M.-C.M.)
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Spencer BL, Deng L, Patras KA, Burcham ZM, Sanches GF, Nagao PE, Doran KS. Cas9 Contributes to Group B Streptococcal Colonization and Disease. Front Microbiol 2019; 10:1930. [PMID: 31497003 PMCID: PMC6712506 DOI: 10.3389/fmicb.2019.01930] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 08/05/2019] [Indexed: 12/20/2022] Open
Abstract
Group B Streptococcus (GBS) is a major opportunistic pathogen in certain adult populations, including pregnant women, and remains a leading etiologic agent of newborn disease. During pregnancy, GBS asymptomatically colonizes the vaginal tract of 20-30% of healthy women, but can be transmitted to the neonate in utero or during birth resulting in neonatal pneumonia, sepsis, meningitis, and subsequently 10-15% mortality regardless of antibiotic treatment. While various GBS virulence factors have been implicated in vaginal colonization and invasive disease, the regulation of many of these factors remains unclear. Recently, CRISPR-associated protein-9 (Cas9), an endonuclease known for its role in CRISPR/Cas immunity, has also been observed to modulate virulence in a number of bacterial pathogens. However, the role of Cas9 in GBS colonization and disease pathogenesis has not been well-studied. We performed allelic replacement of cas9 in GBS human clinical isolates of the hypervirulent sequence-type 17 strain lineage to generate isogenic Δcas9 mutants. Compared to parental strains, Δcas9 mutants were attenuated in murine models of hematogenous meningitis and vaginal colonization and exhibited significantly decreased invasion of human brain endothelium and adherence to vaginal epithelium. To determine if Cas9 alters transcription in GBS, we performed RNA-Seq analysis and found that 353 genes (>17% of the GBS genome) were differentially expressed between the parental WT and Δcas9 mutant strain. Significantly dysregulated genes included those encoding predicted virulence factors, metabolic factors, two-component systems (TCS), and factors important for cell wall formation. These findings were confirmed by qRT-PCR and suggest that Cas9 may regulate a significant portion of the GBS genome. We studied one of the TCS regulators, CiaR, that was significantly downregulated in the Δcas9 mutant strain. RNA-Seq analysis of the WT and ΔciaR strains demonstrated that almost all CiaR-regulated genes were also significantly regulated by Cas9, suggesting that Cas9 may modulate GBS gene expression through other regulators. Further we show that CiaR contributes to GBS vaginal colonization and persistence. Altogether, these data highlight the potential complexity and importance of the non-canonical function of Cas9 in GBS colonization and disease.
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Affiliation(s)
- Brady L. Spencer
- Department of Immunology & Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Liwen Deng
- Department of Immunology & Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Biology, San Diego State University, San Diego, CA, United States
| | - Kathryn A. Patras
- Department of Biology, San Diego State University, San Diego, CA, United States
| | - Zachary M. Burcham
- Department of Animal Sciences, Colorado State University, Fort Collins, CO, United States
| | - Glenda F. Sanches
- Department of Immunology & Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Roberto Alcântara Gomes Biology Institute, Rio de Janeiro State University, Rio de Janeiro, Brazil
| | - Prescilla E. Nagao
- Roberto Alcântara Gomes Biology Institute, Rio de Janeiro State University, Rio de Janeiro, Brazil
| | - Kelly S. Doran
- Department of Immunology & Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Biology, San Diego State University, San Diego, CA, United States
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Jassam SA, Maherally Z, Ashkan K, Pilkington GJ, Fillmore HL. Fucosyltransferase 4 and 7 mediates adhesion of non-small cell lung cancer cells to brain-derived endothelial cells and results in modification of the blood-brain-barrier: in vitro investigation of CD15 and CD15s in lung-to-brain metastasis. J Neurooncol 2019; 143:405-415. [PMID: 31104223 PMCID: PMC6591197 DOI: 10.1007/s11060-019-03188-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 05/06/2019] [Indexed: 02/08/2023]
Abstract
PURPOSE Metastatic non-small cell lung (NSCLC) cancer represents one of the most common types of brain metastasis. The mechanisms involved in how circulating cancer cells transmigrate into brain parenchyma are not fully understood. The aim of this work was to investigate the role of fucosylated carbohydrate epitopes CD15 and sialyated CD15s in cancer adhesion to brain-derived endothelial cells and determine their influence in blood-brain barrier (BBB) disruption METHODS: Three distinct, independent methods were used to measure brain endothelial integrity and include voltohmmeter (EVOM™), impedance spectroscopy (CellZscope®) and electric cell-substrate impedance sensing system (ECIS™). Two fucosyltransferases (FUT4 and 7) responsible for CD15 and CD15s synthesis were modulated in four human cancer cell lines (three lung cancer and one glioma). RESULTS Overexpression of CD15 or CD15s epitopes led to increase in adhesion of cancer cells to cerebral endothelial cells compared with wild-type and cells with silenced CD15 or CD15s (p < 0.01). This overexpression led to the disruption of cerebral endothelial cell monolayers (p < 0.01). Knockdown of FUT4 and FUT7 in metastatic cancer cells prevented disruption of an in vitro BBB model. Surprisingly, although the cells characterised as 'non-metastatic', they became 'metastatic' -like when cells were forced to over-express either FUT4 or FUT7. CONCLUSIONS Results from these studies suggest that overexpression of CD15 and CD15s could potentiate the transmigration of circulating NSCLC cells into the brain. The clinical significance of these studies includes the possible use of these epitopes as biomarkers for metastasis.
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Affiliation(s)
- Samah A Jassam
- Cellular and Molecular Neuro-Oncology Research Group, School of Pharmacy and Biomedical Sciences, University of Portsmouth, White Swan Road, Portsmouth, P01 2DT, UK
| | - Zaynah Maherally
- Cellular and Molecular Neuro-Oncology Research Group, School of Pharmacy and Biomedical Sciences, University of Portsmouth, White Swan Road, Portsmouth, P01 2DT, UK
| | - Keyoumars Ashkan
- Neuro-Surgery, King's College Hospital, Denmark Hill, London, SE5 9RS, UK
| | - Geoffrey J Pilkington
- Cellular and Molecular Neuro-Oncology Research Group, School of Pharmacy and Biomedical Sciences, University of Portsmouth, White Swan Road, Portsmouth, P01 2DT, UK
| | - Helen L Fillmore
- Cellular and Molecular Neuro-Oncology Research Group, School of Pharmacy and Biomedical Sciences, University of Portsmouth, White Swan Road, Portsmouth, P01 2DT, UK.
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Jackson S, Meeks C, Vézina A, Robey RW, Tanner K, Gottesman MM. Model systems for studying the blood-brain barrier: Applications and challenges. Biomaterials 2019; 214:119217. [PMID: 31146177 DOI: 10.1016/j.biomaterials.2019.05.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 05/13/2019] [Accepted: 05/16/2019] [Indexed: 12/21/2022]
Abstract
The blood-brain barrier (BBB) poses a serious impediment to the delivery of effective therapies to the central nervous system (CNS). Over time, various model systems have been crafted and used to evaluate the complexities of the BBB, which includes an impermeable physical barrier and a series of energy-dependent efflux pumps. Models of the BBB have mainly sought to assess changes in endothelial cell permeability, the role of ATP-dependent efflux transporters in drug disposition, and alterations in communication between BBB cells and the microenvironment. In the context of disease, various animal models have been utilized to examine real time BBB drug permeability, CNS dynamic changes, and overall treatment response. In this review, we outline the use of these in vitro and in vivo blood-brain barrier model systems to study normal physiology and diseased states. These current models each have their own advantages and disadvantages for studying the response of biologic processes to physiological and pathological conditions. Additional models are needed to mimic more closely the dynamic quality of the BBB, with the goal focused on potential clinical applications.
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Affiliation(s)
- Sadhana Jackson
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, United States.
| | - Caitlin Meeks
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, United States
| | - Amélie Vézina
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, United States
| | - Robert W Robey
- Multidrug Resistance Section, Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, United States
| | - Kandice Tanner
- Tissue Morphodynamics Unit, Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, United States
| | - Michael M Gottesman
- Multidrug Resistance Section, Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, United States
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41
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Sato K. [Consideration for future in vitro BBB models - technical development to investigate the drug delivery to the CNS]. Nihon Yakurigaku Zasshi 2019; 152:287-294. [PMID: 30531099 DOI: 10.1254/fpj.152.287] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Blood vessels in the central nervous system (CNS) limit the material exchange between blood and parenchyma by blood brain barrier (BBB). At present, no appropriate in vitro BBB models are available for the investigation whether or not the candidate compounds for new drugs could be delivered to the CNS. This causes huge difficulties of the development of CNS drugs and prediction of CNS adverse effects. In this review, I first outline the structures and functions of BBB, together with the parameters used for the quantification of BBB functions. I also introduce the history of in vitro BBB models used in the drug development so far, i.e., the transition from non-cell models to the models using primary culture of rodent cells, porcine, bovine, cell lines, etc. More recently, the application of human cells differentiated from human induced pluripotent stem cells and microfluidic engineering have already started. BBB is essential for the maintenance of brain homeostasis and the mechanisms of the BBB development will be clarified by reproducing functional BBB on the dish. The new in vitro models and the data may provide accurate prediction of drug delivery to the CNS and the improvement of the evaluation system for toxicity and safety, thereby leading to successful launch of new drugs on the market.
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42
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Vu K, Garcia JA, Gelli A. Cryptococcal Meningitis and Anti-virulence Therapeutic Strategies. Front Microbiol 2019; 10:353. [PMID: 30863389 PMCID: PMC6399105 DOI: 10.3389/fmicb.2019.00353] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Accepted: 02/11/2019] [Indexed: 01/31/2023] Open
Abstract
Fungal infections of the central nervous system are responsible for significant morbidity and mortality. Cryptococcus neoformans (Cn) is the primary cause of fungal meningitis. Infection begins in the lung after inhalation of fungal spores but often spreads to other organs, particularly the brain in immunosuppressed individuals. Cn’s ability to survive phagocytosis and endure the onslaught of oxidative attack imposed by the innate immune response facilitates dissemination to the central nervous system (CNS). Despite the success of Cn at bypassing innate immunity, entry into the heavily protected brain requires that Cn overwhelm the highly restricted blood-brain barrier (BBB). This is a formidable task but mounting evidence suggests that Cn expresses surface-bound and secreted virulence factors including urease, metalloprotease, and hyaluronic acid that can undermine the BBB. In addition, Cn can exploit multiple routes of entry to gain access to the CNS. In this review, we discuss the cellular and molecular interface of Cn and the BBB, and we propose that the virulence factors mediating BBB crossing could be targeted for the development of anti-virulence drugs aimed at preventing fungal colonization of the CNS.
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Affiliation(s)
- Kiem Vu
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Javier A Garcia
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Angie Gelli
- Department of Pharmacology, School of Medicine, University of California, Davis, Davis, CA, United States
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43
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Santiago-Tirado FH, Klein RS, Doering TL. An In Vitro Brain Endothelial Model for Studies of Cryptococcal Transmigration into the Central Nervous System. ACTA ACUST UNITED AC 2019; 53:e78. [PMID: 30776307 DOI: 10.1002/cpmc.78] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Cryptococcus neoformans is an environmental yeast found worldwide that causes lethal brain infections, particularly in immunocompromised hosts. In 2016, there were 280,000 cases of cryptococcal meningitis in the HIV+ population, two-thirds of them fatal; other immunocompromised patients are also affected. The burden of cryptococcal disease and the limits of current chemotherapy create a pressing need for improved treatment. One hindrance to the development of new therapies is lack of understanding of how this pathogen breaches the barriers protecting the brain. Here we describe a tool for investigating this process. This simple in vitro blood-brain-barrier (BBB) model, based on a human brain endothelial cell line grown on a permeable membrane, may be used to assay the BBB transmigration of C. neoformans or other neurotropic pathogens. © 2019 by John Wiley & Sons, Inc.
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Affiliation(s)
- Felipe H Santiago-Tirado
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri.,Current address: Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana
| | - Robyn S Klein
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Tamara L Doering
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri
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44
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Na Pombejra S, Jamklang M, Uhrig JP, Vu K, Gelli A. The structure-function analysis of the Mpr1 metalloprotease determinants of activity during migration of fungal cells across the blood-brain barrier. PLoS One 2018; 13:e0203020. [PMID: 30161190 PMCID: PMC6117016 DOI: 10.1371/journal.pone.0203020] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 08/14/2018] [Indexed: 12/21/2022] Open
Abstract
Cryptococcal meningoencephalitis, the most common form of cryptococcosis, is caused by the opportunistic fungal pathogen, Cryptococcus neoformans. Molecular strategies used by C. neoformans to invade the central nervous system (CNS) have been the focus of several studies. Recently, the role of a novel secreted metalloprotease (Mpr1) in the pathogenicity of C. neoformans was confirmed by studies demonstrating that Mpr1 mediated the migration of fungal cells into the CNS. Given this central function, the aim here was to identify the molecular determinants of Mpr1 activity and resolve their role in the migration of cryptococci across the blood-brain barrier (BBB). The Mpr1 protein belongs to an understudied group of metalloproteases of the M36 class of fungalysins unique to fungi. They are generally synthesized as propeptides with fairly long prodomains and highly conserved regions within their catalytic core. Through structure-function analysis of Mpr1, our study identified the prodomain cleavage sites of Mpr1 and demonstrated that when mutated, the prodomain appears to remain attached to the catalytic C-terminus of Mpr1 rendering a nonfunctional Mpr1 protein and an inability for cryptococci to cross the BBB. We found that proteolytic activity of Mpr1 was dependent on the coordination of zinc with two histidine residues in the active site of Mpr1, since amino acid substitutions in the HExxH motif abolished Mpr1 proteolytic activity and prevented the migration of cryptococci across the BBB. A phylogenetic analysis of Mpr1 revealed a distinct pattern likely reflecting the neurotropic nature of C. neoformans and the specific function of Mpr1 in breaching the BBB. This study contributes to a deeper understanding of the molecular regulation of Mpr1 activity and may lead to the development of specific inhibitors that could be used to restrict fungal penetration of the CNS and thus prevent cryptococcal meningoencephalitis-related deaths.
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Affiliation(s)
- Sarisa Na Pombejra
- Department of Pharmacology, School of Medicine, University of California, Davis, California, United States of America
| | - Mantana Jamklang
- Department of Pharmacology, School of Medicine, University of California, Davis, California, United States of America
| | - John P. Uhrig
- Department of Pharmacology, School of Medicine, University of California, Davis, California, United States of America
| | - Kiem Vu
- Department of Pharmacology, School of Medicine, University of California, Davis, California, United States of America
| | - Angie Gelli
- Department of Pharmacology, School of Medicine, University of California, Davis, California, United States of America
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46
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Ivask A, Pilkington EH, Blin T, Käkinen A, Vija H, Visnapuu M, Quinn JF, Whittaker MR, Qiao R, Davis TP, Ke PC, Voelcker NH. Uptake and transcytosis of functionalized superparamagnetic iron oxide nanoparticles in an in vitro blood brain barrier model. Biomater Sci 2018; 6:314-323. [PMID: 29239410 DOI: 10.1039/c7bm01012e] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Two major hurdles in nanomedicine are the limited strategies for synthesizing stealth nanoparticles and the poor efficacy of the nanoparticles in translocating across the blood brain barrier (BBB). Here we examined the uptake and transcytosis of iron oxide nanoparticles (IONPs) grafted with biomimetic phosphorylcholine (PC) brushes in an in vitro BBB model system, and compared them with bare, PEG or PC-PEG mixture grafted IONPs. Hyperspectral imaging indicated IONP co-localization with cells. Quantitative analysis with total reflection X-ray fluorescence spectrometry showed that after 24 h, 78% of PC grafted, 68-69% of PEG or PC-PEG grafted, and 30% of bare IONPs were taken up by the BBB. Transcytosis of IONPs was time-dependent and after 24 h, 16-17% of PC or PC-PEG mixture grafted IONPs had passed the BBB model, significantly more than PEG grafted or bare IONPs. These findings point out that grafting of IONPs with PC is a viable strategy for improving the uptake and transcytosis of nanoparticles.
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Affiliation(s)
- Angela Ivask
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Future Industries Institute, University of South Australia, Mawson Lakes, SA, Australia
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Andrews AM, Lutton EM, Cannella LA, Reichenbach N, Razmpour R, Seasock MJ, Kaspin SJ, Merkel SF, Langford D, Persidsky Y, Ramirez SH. Characterization of human fetal brain endothelial cells reveals barrier properties suitable for in vitro modeling of the BBB with syngenic co-cultures. J Cereb Blood Flow Metab 2018; 38:888-903. [PMID: 28534661 PMCID: PMC5987936 DOI: 10.1177/0271678x17708690] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Endothelial cells (ECs) form the basis of the blood-brain barrier (BBB), a physical barrier that selectively restricts transport into the brain. In vitro models can provide significant insight into BBB physiology, mechanisms of human disease pathology, toxicology, and drug delivery. Given the limited availability of primary human adult brain microvascular ECs ( aBMVECs), human fetal tissue offers a plausible alternative source for multiple donors and the opportunity to build syngenic tri-cultures from the same host. Previous efforts to culture fetal brain microvascular ECs ( fBMVECs) have not been successful in establishing mature barrier properties. Using optimal gestational age for isolation and flow cytometry cell sorting, we show for the first time that fBMVECs demonstrate mature barrier properties. fBMVECs exhibited similar functional phenotypes when compared to aBMVECs for barrier integrity, endothelial activation, and gene/protein expression of tight junction proteins and transporters. Importantly, we show that tissue used to culture fBMVECs can also be used to generate a syngenic co-culture, creating a microfluidic BBB on a chip. The findings presented provide a means to overcome previous challenges that limited successful barrier formation by fBMVECs. Furthermore, the source is advantageous for autologous reconstitution of the neurovascular unit for next generation in vitro BBB modeling.
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Affiliation(s)
- Allison M Andrews
- 1 Department of Pathology & Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA.,2 The Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Evan M Lutton
- 1 Department of Pathology & Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Lee A Cannella
- 1 Department of Pathology & Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA.,2 The Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Nancy Reichenbach
- 1 Department of Pathology & Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Roshanak Razmpour
- 1 Department of Pathology & Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Matthew J Seasock
- 1 Department of Pathology & Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Steven J Kaspin
- 1 Department of Pathology & Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Steven F Merkel
- 1 Department of Pathology & Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA.,2 The Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Dianne Langford
- 3 Department of Neuroscience, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Yuri Persidsky
- 1 Department of Pathology & Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA.,2 The Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Servio H Ramirez
- 1 Department of Pathology & Laboratory Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA.,2 The Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA.,4 The Shriners Hospitals Pediatric Research Center, Philadelphia, PA, USA
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48
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Aaron PA, Jamklang M, Uhrig JP, Gelli A. The blood-brain barrier internalises Cryptococcus neoformans via the EphA2-tyrosine kinase receptor. Cell Microbiol 2018; 20. [PMID: 29197141 DOI: 10.1111/cmi.12811] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 11/13/2017] [Accepted: 11/14/2017] [Indexed: 02/06/2023]
Abstract
Cryptococcus neoformans is an opportunistic fungal pathogen that causes life-threatening meningitis most commonly in populations with impaired immunity. Here, we resolved the transcriptome of the human brain endothelium challenged with C. neoformans to establish whether C. neoformans invades the CNS by co-opting particular signalling pathways as a means to promote its own entry. Among the 5 major pathways targeted by C. neoformans, the EPH-EphrinA1 (EphA2) tyrosine kinase receptor-signalling pathway was examined further. Silencing the EphA2 receptor transcript in a human brain endothelial cell line or blocking EphA2 activity with an antibody or chemical inhibitor prevented transmigration of C. neoformans in an in vitro model of the blood-brain barrier (BBB). In contrast, treating brain endothelial cells with an EphA2 chemical agonist or an EphA2 ligand promoted greater migration of fungal cells across the BBB. C. neoformans activated the EPH-tyrosine kinase pathway through a CD44-dependent phosphorylation of EphA2, promoting clustering and internalisation of EphA2 receptors. Moreover, HEK293T cells expressing EphA2 revealed an association between EphA2 and C. neoformans that boosted internalisation of C. neoformans. Collectively, the results suggest that C. neoformans promotes EphA2 activity via CD44, and this in turn creates a permeable barrier that facilitates the migration of C. neoformans across the BBB.
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Affiliation(s)
- Phylicia A Aaron
- Department of Pharmacology, School of Medicine, Genome and Biomedical Sciences Facility, University of California, Davis, California, USA
| | - Mantana Jamklang
- Department of Pharmacology, School of Medicine, Genome and Biomedical Sciences Facility, University of California, Davis, California, USA
| | - John P Uhrig
- Department of Pharmacology, School of Medicine, Genome and Biomedical Sciences Facility, University of California, Davis, California, USA
| | - Angie Gelli
- Department of Pharmacology, School of Medicine, Genome and Biomedical Sciences Facility, University of California, Davis, California, USA
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49
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Fadzen CM, Wolfe JM, Cho CF, Chiocca EA, Lawler SE, Pentelute BL. Perfluoroarene-Based Peptide Macrocycles to Enhance Penetration Across the Blood-Brain Barrier. J Am Chem Soc 2017; 139:15628-15631. [PMID: 28992407 PMCID: PMC5818988 DOI: 10.1021/jacs.7b09790] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Here we describe the utility of peptide macrocyclization through perfluoroaryl-cysteine SNAr chemistry to improve the ability of peptides to cross the blood-brain barrier. Multiple macrocyclic analogues of the peptide transportan-10 were investigated that displayed increased uptake in two different cell lines and improved proteolytic stability. One of these analogues (M13) exhibited substantially increased delivery across a cellular spheroid model of the blood-brain barrier. Through ex vivo imaging of mouse brains, we demonstrated that this perfluoroarene-based macrocycle of TP10 exhibits increased penetration of the brain parenchyma following intravenous administration in mice. Finally, we evaluated macrocyclic analogues of the BH3 domain of the BIM protein to assess if our approach would be applicable to a peptide of therapeutic interest. We identified a BIM BH3 analogue that showed increased penetration of the brain tissue in mice.
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Affiliation(s)
- Colin M. Fadzen
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Justin M. Wolfe
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Choi-Fong Cho
- Harvey Cushing Neuro-Oncology Laboratories, Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - E. Antonio Chiocca
- Harvey Cushing Neuro-Oncology Laboratories, Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Sean E. Lawler
- Harvey Cushing Neuro-Oncology Laboratories, Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Bradley L. Pentelute
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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50
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Yang CL, Wang J, Zou LL. Innate immune evasion strategies against Cryptococcal meningitis caused by Cryptococcus neoformans. Exp Ther Med 2017; 14:5243-5250. [PMID: 29285049 PMCID: PMC5740712 DOI: 10.3892/etm.2017.5220] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 05/31/2017] [Indexed: 12/14/2022] Open
Abstract
As an infectious fungus that affects the respiratory tract, Cryptococcus neoformans (C. neoformans) commonly causes asymptomatic pulmonary infection. C. neoformans may target the brain instead of the lungs and cross the blood-brain barrier (BBB) in the early phase of infection; however, this is dependent on successful evasion of the host innate immune system. During the initial stage of fungal infection, a complex network of innate immune factors are activated. C. neoformans utilizes a number of strategies to overcome the anti-fungal mechanisms of the host innate immune system and cross the BBB. In the present review, the defensive mechanisms of C. neoformans against the innate immune system and its ability to cross the BBB were discussed, with an emphasis on recent insights into the activities of anti-phagocytotic and anti-oxidative factors in C. neoformans.
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Affiliation(s)
- Cheng-Liang Yang
- Translational Neuroscience and Neural Regeneration and Repair Institute, The First Hospital of Yichang, China Three Gorges University, Yichang, Hubei 443002, P.R. China.,Institute of Cell Therapy, The First Hospital of Yichang, China Three Gorges University, Yichang, Hubei 443002, P.R. China
| | - Jun Wang
- Translational Neuroscience and Neural Regeneration and Repair Institute, The First Hospital of Yichang, China Three Gorges University, Yichang, Hubei 443002, P.R. China.,Institute of Cell Therapy, The First Hospital of Yichang, China Three Gorges University, Yichang, Hubei 443002, P.R. China
| | - Li-Li Zou
- Translational Neuroscience and Neural Regeneration and Repair Institute, The First Hospital of Yichang, China Three Gorges University, Yichang, Hubei 443002, P.R. China.,Institute of Cell Therapy, The First Hospital of Yichang, China Three Gorges University, Yichang, Hubei 443002, P.R. China.,Department of Microbiology and Immunology, Medical College, China Three Gorges University, Yichang, Hubei 443002, P.R. China
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